Seniors lag behind the rest of the population in using the Internet and social media, but there are many benefits of going online.
Robert Boyd of San Francisco didn't know much about the Internet when a tourist from Australia approached him several years ago and asked if she could post his photo on her Facebook account. Curious about Facebook and the Internet, he soon started visiting San Francisco's Community Technology Network (CTN) at the Downtown Senior Center.
After he learned the basics, the fashion enthusiast started posting daily photos of himself on Facebook and Twitter. He now hosts a talk show on YouTube and makes guest appearances on other fashion programs. Like many other seniors, Boyd is discovering how to connect to a larger world than the one he knows in his neighborhood.
The CTN serves 25 senior centers throughout San Francisco, where visitors use computers to watch videos, answer email, research medical information, hear music and keep up with their friends on Facebook. It's part of a larger movement to get older adults online.
Though seniors have been slow to take advantage of the Internet, and social media in particular, the numbers are increasing. In 2014, the Pew Research Center reported that 59 percent of those 65 and up said they go online, a 6 percentage point increase from the previous year. Forty-seven percent said they had a high-speed broadband connection at home, and 77 percent have a cell phone, up from 69 percent in April 2012.
Despite these gains, many seniors don't participate in the online world. Forty-one percent do not use the Internet at all, 53 percent do not have broadband access at home and 23 percent don't use cell phones. The figures are worse for older adults 75-79, with only 47 percent using the Internet and 34 percent having a broadband connection.
Yet, being part of the technological world has many benefits for seniors. A Stanford study found that "using tech to connect with loved ones was related to higher life satisfaction, lower loneliness and general attainment of meaningful goals—being happy, independent," said researcher Tamara Sims of the Stanford Center on Longevity (quoted in Silicon Valley).
The research team surveyed 445 people between the ages of 80 and 93, asking the reasons for using cell phones, personal computers, video streaming services and other digital tools. Despite the Pew figures, most of the adults over 80 said they used at least one technological device regularly, which they said improved their physical and mental well-being.
Research is increasingly showing that staying socially engaged keeps people healthy. For older adults, social engagement can be more difficult after retirement when we no longer have our main social structure. As we age, we lose spouses and friends, and bad weather or physical problems can keep us inside, reinforcing the isolation. Surveys show that one-quarter of seniors live alone.
That's why technology can be valuable. With video chat services like Skype or FaceTime, you don't have to leave your home to have a face-to-face conversation with a friend or family member. On Facebook, you can find old friends and make new ones through mutual interests—whether it's the Civil War, genealogy or Charles Dickens' novels.
On Facebook or Flickr, your friends or family can share photos of their vacation on a daily basis, so you almost feel as if you are traveling with them. On Facebook or YouTube, you can watch videos of your grandson enjoying his birthday and laugh while he stuffs his mouth with cake.
Sitting at your desk at home, you can use your computer or Nintendo Wii to play various games, either by yourself or with others. On Twitter, you can follow your favorite politician or movie star and create conversations with others.
In its survey, the Pew Center found that a significant majority of older adults said they need assistance when it comes to using new digital devices. Among seniors who go online but don't use social networking sites such as Facebook or Twitter, 56 percent said they would need assistance if they wanted to use these sites to connect with friends or family members.
Fortunately, there are a lot of resources. Senior centers, libraries, schools and community centers offer beginning courses on using different media. And don't be afraid to ask your grandchild or younger neighbor for some help.
Eldercare Locator's "Staying Connected: Technology Options for Older Adults" guide offers basic information about Facebook, email, texting, YouTube, Twitter, Skype and other technological tools.
Many senior living facilities also offer classes as well as computer rooms, where you can ask the person sitting next to you how the heck you send a message on Facebook.
"Elders who use tech tools feel less lonely, more physically fit, Stanford study finds," Nov. 29, 2016, Silicon Valley.
"5 Benefits of Technology to Share with Seniors and Their Caregivers" Caregiver Stress.
"5 Benefits of Social Media for Seniors – Let's Help Them Get Online," Senior Care Corner.
"Older Adults and Technology Use," April 3, 2014, Pew Research Center.
"5 Ways Technology Can Benefit Your Grandparents," Huffington Post.
"Computer Skills Give Senior Fashion Icon Whole New Audience," Jan. 24, 2017 SF Connected.


I previously did a feature look at the lead actress from Netflix's television series adaptation of DEAR WHITE PEOPLE, but I would be remiss if I didn't also point out that Antoinette Robertson, another principal actress on the show, is also the lovely. Let's take a few minutes and allow me to show you yet another reason why you should be seeking out this excellent series.
Antoinette Robertson takes what seems to be a two-dimensional character at the series start and takes her down a complex path. And she smolders on screen in every scene. I can't get enough!
If you enjoyed this, be sure to check out other installments of my series on The Lovely ladies of the world!


This fine American lyric tenor was born in Hollywood in 1957 but moved to New York at an early age. When he was 15, he applied to study singing to be told that "we don't teach children". After hearing him, the rules were quickly changed! In 1983, he won the Enrico Caruso voice competition in Italy and in 1984, he made his debut with the New York City Opera as Rodolfo. He made his Metropolitan debut in 1989 and his beautiful voice has taken him to all the major opera houses in the world. He is firmly established as one of the world's finest lyric tenors.


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Indigenous leaders fight for bigger role in new N.W.T. university
Indigenous leaders in the N.W.T. are asking for a bigger role in Aurora College's transition into a polytechnic university.
"This is our golden opportunity to go back to who we are as Indigenous people," chief says
Anna Desmarais · CBC News · Posted: Nov 24, 2020 1:23 PM CT | Last Updated: November 25, 2020
Aurora College will become a polytechnic university by 2025. (Mario De Ciccio/CBC)
Indigenous leaders in the N.W.T. are asking for a bigger role in Aurora College's transition into a polytechnic university.
Hotıì ts'eeda, a research unit for the Tłı̨chǫ government, released a discussion paper earlier this month arguing for a new governance structure at the university.
The discussion paper is in response to a discussion paper released last August by the N.W.T. Department of Education, Culture and Employment, soliciting feedback about the governance of the future polytechnic. It suggested two governing bodies with at least five board members who are residents of the territory, and three who are Indigenous.
The Hotıì ts'eeda proposal also includes two councils to govern the university.
The first council would resemble a board of governors, but would include individuals from the N.W.T. with a mixed set of skills who would be responsible for the university's budget and setting the university's mandate. The council would include students and staff.
The second council is similar to a senate, but would include a mix of academics and leaders from Indigenous communities. There would also be room on this council for the N.W.T. government and rotating seats for "major industry partners" like the N.W.T. Chamber of Commerce, or those in the social sector.
Dr. John B. Zoe, chair of Hotıì ts'eeda and co-author of the discussion paper, said he was motivated to reply to the government's first look at how to govern the college because it didn't go far enough to include Indigenous peoples.
"It doesn't take into consideration what the Indigenous communities are about," Zoe told CBC, talking about on-the-land programming and traditional knowledge.
John B. Zoe, chair of Hotii T'seeda, says a new governance structure at the N.W.T.'s upcoming polytechnic university would better reflect the people of the North. (Avery Zingel/CBC)
"We've never been part of something that's been growing. We've always been subject to it, but not in a participating way."
R.J. Simpson, the minister of education, culture and employment, said that engagement with Indigenous leaders and stakeholders is valued and important to the success of the transformation of the college into a polytechnic university.
He said the input he's heard about the transformation of the college into a polytechnic university through discussion papers "was overall a positive experience."
"However, we will continuously adapt our engagement approach based on the feedback we receive," he said. "There will also be opportunity for additional input during the legislative process by all partners, stakeholders and the public."
Governance style would reflect northern culture
The Hotıì ts'eeda model also recommends a president with a PhD, and that the university's chancellor should be a traditional knowledge holder.
Governing Aurora in this new way, Zoe said, would make this university uniquely northern. It would also help convince N.W.T. students to stay in the territory, instead of leaving to study at Yukon University or down south.
"We can do something that has to do with Indigenous resurgence, learning about what we have," he said. "We're continually ignoring half the population … instead of trying to strengthen our way of life."
Dene National Chief Norman Yakeleya says he wants to see elders involved in teaching courses at the university, like instructing prospective nurses on traditional medicines. (Sidney Cohen/CBC News)
Norman Yakeleya, chief of the Dene Nation, supports the proposed model by Hotıì ts'eeda.
"This is our golden opportunity to go back to who we are as Dene people and Indigenous people," Yakeleya told CBC.
Model suggests Indigenous resurgence studies
The education department's most recent discussion paper on Aurora College, released in October, suggests four areas of study instead: skilled trades and technology; earth resources and environmental management; northern health, education and community services; and business and leadership.
These areas of teaching and research provide the university with "a basis for planning and implementing new and enhanced programming" at campuses and community learning centres, the report reads.
Zoe said the education department's proposed areas of study are "heavy-laden" with mining and the public service, two of the biggest areas of employment in the N.W.T.
The Hotıì ts'eeda model includes six additional schools for students, including schools dedicated to Indigenous resurgence, and land connection and sustainability. Within the schools, students could take a masters in Indigenous governance, knowledge and culture, or classes in northern agriculture.
"We're ... making sure that what's been ignored for a long time, that there's space for it." - Dr. John B. Zoe, chair of Hotii T'seeda
Zoe said the suggestions in their paper are not meant to replace what the territory's working group has already come up with, but to add Indigenous knowledge to that list.
"[It's about] making sure that what's been ignored for a long time, that there's space for it," he said.
Leaders want more roles for elders
David Poitras, chief of Salt River First Nation, tells a story to show how important knowledge from the elders is.
One elder caught all the big beavers in the river, while everyone else struggled with small ones.
A young person asked the elder how they were so successful. The elder told the young person to put the traps lower in the water, so the little beavers swim over them - and the big ones get caught.
David Poitras, chief of Salt River First Nation, said there could be a loss of knowledge if elders are not included in the new polytechnic. (Anna Desmarais/CBC)
It's this kind of knowledge, including survival on the land, spirituality and how to live in the bush, that Poitras wants to see included in the plans for the territory's first polytechnic.
"To me, they don't involve enough elders in what they do. It's getting to be a loss of knowledge," he said.
[Elders] have a lot to offer, and I think it's time for the territorial government to acknowledge that."
N.W.T. presents implementation plan for Aurora College to become university
Aurora College releases strategic plan to begin transition to polytechnic university
Yakeleya said they want the university to recognize how important traditional knowledge is to people in the communities.
"These knowledge keepers, they are equivalent to professors and teachers in our community," he said.
"They are the keepers of our way of life … and we've got to look at how to incorporate them into our education system."
Yakeleya and Poitras suggest having traditional knowledge holders involved in teaching some of these courses. For example, Yakeleya said a nursing program should include lessons on harvesting and working with traditional medicines.
N.W.T. government proposes polytechnic university specializes in 4 fields
More academic freedom proposed for N.W.T.'s Aurora College in government's latest report

redpajama_set_name: RedPajamaCommonCrawl


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I must admit, I usually enjoy writing these little essays. I find myself jotting down little notes from time to time, and, over the course of a couple of weeks, they just kind of come together into a collection of (mostly) integrated ideas. It's a fun process and something I usually look forward to.
Not this time though. No this time I felt compelled to talk about something that has in many ways been a huge issue in my life as a kid, then a teenager, and now as a child psychologist. This issue is bullying.
I've been on all sides of the bullying continuum. As a kid I was teased for my appearance, mocked relentlessly and humiliated. Later, as a teenager, I dished out plenty of the same. I teased just about anyone in my path, and this went on for a while. Maybe this was a way of dealing with my own experiences. One thing I know to be unequivocally true, is that this kind of stuff leaves scars. I've got plenty of my own, and am sure I've created a few myself. As much as I enjoy working with kids, I've often thought that it was my penance in this life to try and guide kids through their own troubled times as a way of making peace with my own past.
An image that will always haunt me came from one of my first experiences as a counselor in my early days as a psychology student. I had an assignment at a school at the end of the summer and it was hot. Not just warm, but summer in Chicago hot. A skinny kid came in wearing a baggy sweatshirt, and I made a sarcastic remark about him being overdressed. He managed a little smile, sat down, and we talked for a while. He talked to me about his parents, his neighborhood, and then finally what it was like to be gay in an Irish-Catholic neighborhood. I was very touched by his story, and told him to please come back again.
As he got up to leave, he took a long look at me, and then slowly rolled up his sleeves. There were knife marks across and all up and down his arms. Not little ones either, but long and ugly scars from years of cutting himself.
"This is why I wear long sleeve shirts in the summer" he said quietly.
It was a statement that I've never forgotten.
I never saw this particular kid again, as my assignment ended shortly afterwards, and he never showed up for his next appointment. I've always wondered what happened to him, and I find myself hoping that he somehow hung on. Still, his scars ran deep, and there were a lot of them.
Unfortunately those weren't the last scars that I've seen, but it was the last time I ever made a sarcastic comment about a kid wearing long sleeves. It reminded me of a lesson that I often forget. Words matter. Sometimes they matter so much that they make vulnerable and scared children run knives across their arms, sometimes fatally. It's all a little terrifying actually. You want to tell these kids that this stuff is not going to last forever. That one day they will be out of High School and free from small minds and mean people.
But you really can't promise that.
What you can do is listen and try and understand. You can give them a place where they can talk about the isolation and the confusion and the humiliation. And some of them will survive and become the "massive characters" that Kahlil Gibran discusses in the above quotation. Many of the world's great success stories start in this very manner. But some of them wont. Some of them will spend the rest of their lives thinking that they aren't welcome in a world that has been so hard on them.
What we can also do is advocate for those who have yet to realize the power of their own voices. Personally I've come to see this as my duty and responsibility. Bullying has become one of the most serious epidemics of our generation, and it's killing our kids, both literally and figuratively. If you are in a position to influence a child in your life, please take the time to talk to them about this.
A life may depend on it.


High Blood Pressure—Cause of Death!
What exactly is Blood Pressure Protocol?
How did Blood Pressure Protocol Come into Being?
What is contained in Blood Pressure Protocol?
Why should you choose Blood Pressure Protocol?
We all know that high blood pressure is the main cause of death in today's times. About 25,000 people are affected with hypertension and blood pressure in US alone.
But this hypertension and high blood pressure is not only the problem in US, it affects a large number of people in the world over.
Hypertension is caused by consistently high blood pressure, especially in the middle and old age groups. The main cause behind high blood pressure is narrowing down of valves that take blood to the heart, known as arteries.
When these arteries get blocked, havoc is wreaked! Due to hypertension, certain other life threatening situations can occur, which either can lead to paralysis or worse, death.
Can you imagine a life without having to visit your doctor for tests repeatedly? Imagine being able to eliminate the symptoms of high blood pressure for good—the headaches, nausea, confusion, fatigue, chest pain, breathing difficulties, or pain in the arm of neck.
You can get rid of all these symptoms in an easy way now—not the way doctors prescribe!
The medical world revolves around drugs and your doctor will certainly prescribe you a host of drugs to treat your hypertension and high blood pressure.
These drugs come with side effects of their own, but now there is a completely natural solution to lower that high blood pressure! This natural treatment, known as blood pressure protocol is the ultimate solution to get rid of all those drugs and medicines that are accumulating in your system.
Blood Pressure Protocol is the control program for anyone wanting to control his/her high blood pressure. This protocol, known as David Riley Blood Pressure Protocol is a natural way to control blood pressure.
Unlike the medicines and drugs prescribed by doctors to control blood pressure, it uses completely natural ways to control hypertension and high blood pressure.
It is a downloadable e-book in which the author, David Riley promises to show you a natural way to reduce blood pressure. The program claims to work by using vitamins, natural foods, and supplements instead of blood pressure medications and drugs.
The program comes with Blood Pressure protocol pdf, and blood pressure protocol guide with complete instructions on which foods to take and which ones to avoid if you have high blood pressure and hypertension.
Blood Pressure Protocol was made by David Riley, who had previously experienced severe hypertension and had gone through a tough time when the doctors prescribed him medicines and drugs to control his blood pressure.
Tired of taking all those drugs that were affecting his mood, sleep and health, David Riley collaborated with Dr. Miles Channing, a hypertension cardiologist and specialist to make this blood pressure protocol.
David Riley shared his story which revealed that for the past 12 years, he had been a victim of serious high blood pressure and hypertension.
It started when he experienced severe pain in the chest and shortage of breath. When the doctors diagnosed him severe hypertension that could lead to heart stroke, David had to undergo a medication course and regular tests during which he was instructed to take 8 medicines simultaneously.
These medications came with their side effects such as numbness in the hands, chest pains, erectile dysfunction, and pain in the abdomen. To get rid of all these issues and side effects, David Riley began researching on finding an alternative to all the heavy medicines and drugs.
He came across an old article that featured Dr. Miles Channing's interview. At this time, Dr. Channing lived with Yanomamo Indian tribe and had been living with them for almost 3 years.
During that time, he had noticed that there were no cases of high blood pressure among the Yanomamo Indians. The secret behind this was the "intersalt" or the "no-salt diet" which contained foods rich in proteins, fiber, and coenzyme Q10 antioxidant found in green leafy vegetables, nuts, chicken, beef, etc.
But what was so remarkable about this protocol? The protocol was aimed at lowering blood pressure and hypertension by using completely natural and safe food without the use of salt.
It is so effective that the people who used this protocol expressed that their blood pressure had dropped considerably with only 2 weeks of use in their Blood Pressure Protocol reviews.
You must be thinking why this blood pressure protocol is so remarkable? What has it got to offer that is different from the medications and drugs prescribed by doctors and physicians? David Riley and Dr. Channing had teamed up to turn the findings by Dr. Channing into a reality.
They came up with an easy to understand step by step guide called the Blood Pressure Protocol guide that is present in Blood Pressure Protocol PDF containing a complete guide on how to use this miracle treatment.
The health tips in this E-book are from American researcher Dr. Channing who had spent much of his career in Brazil living among the native tribe of Yanomamo Indians.
Channing suggested some foods that Yanomamo Indians ate include nuts, shellfish, pork, beef, chicken, dark green leafy vegetables and cold water fish such as herring, tuna, and salmon.
He advised that if more of these foods are incorporated into the daily diet, blood pressure would not affect you and the problem of high blood pressure and hypertension will also be solved.
In addition, the program comes with Blood Pressure Protocol PDF and Blood Pressure Protocol guide PDF for clearly defining the correct foods to take in case you have high blood pressure and hypertension.
The program also contains a series of videos showing the foods and the different recipes you can make to include all the necessary nutrients that will reduce your blood pressure.
Now you must be wondering how this miracle treatment works. It is very simple and easy to understand.
Are you tired of using drugs and medicines to treat your high blood pressure? Do you want to get rid of spending lots of money for blood pressure medications and supplies every month?
If that is the case, Blood Pressure Protocol is the best natural solution to all your worries and it is extremely easy to use and understand.
The Super Smoothie Bible is a short guide that include 17 tasty recipes of smoothies that will help you lower your blood pressure more quickly.
It helps to avoid both major and minor side effects of medications: some of the major effects of using anti-hypertension medications are diarrhea, heartburn, lethargy, headaches, depression, fatigue, weakness, and sleeping difficulties.
It comes with a money-back guarantee: If you are doubtful about this Protocol, then you can consult your doctor. Not just that, Blood Pressure Protocol comes with a 60-day money-back guarantee from the date of purchases so if you don't see any positive results, you can get your money back.
In essence, Blood Pressure Protocol is an effective and extremely easy remedy to use in place of all those medications and drugs to control hypertension. The foods mentioned in the Protocol are all natural and easily available so you don't have to worry at all. The Protocol is the real natural solution to control that high blood pressure that can make your life so easy and free of all stress.
← What is Herpes Blitz Protocol? Does it Really Works or Scam?


John Muntean has a Ph.D. in solid-state carbon-13 nuclear magnetic resonance. He's been creating magic angle sculptures that change based on perspective. People are in disbelief at how much the art changes based on its positioning.


text:
Dear Tumblr: Banning "Adult Content" Won't Make Your Site Better But It Will Harm Sex-Positive Communities
Katharine Trendacosta and Jillian C. York
Onlinecensorship.org, for me, was about drawing attention to how social media censorship disproportionately affects marginalized communities. The communities that could most benefit from protected spaces online are being excluded from participation.
Ramzi Jaber
Blunt Policies and Secretive Enforcement Mechanisms: LGBTQ+ and Sexual Health on the Corporate Web
Jillian C. York
Facebook Releases First-Ever Community Standards Enforcement Report
For the first time, Facebook has published detailed information about how it enforces its own community standards. On Tuesday, the company announced the release...
Blunt Measures on Speech Serve No One: The Story of San Diego CityBeat
It's no secret: Social media has changed the way that we access news. According to the Pew Research Center, two-thirds of Americans report getting at least some...
Of course we should be able to use social networks to protest against puritanical views about women's bodies. And we need to defy the idea that the only acceptable images of women are those selected to suit the male gaze, or that men (or tech firms!) can be the ones to decide whether our nipples are sexual or not.
Facebook Must Go Further on Transparency
The Onlinecensorship.org Team
The Onlinecensorship.org responds to Facebook's "hard questions" on hate speech.
News, Interest and Intrigue: Parsing Facebook's Latest Content Moderation Policy Announcement
Matthew Stender
Censorship against Palestinians brings Onlinecensorship.org back to its roots
Jessica Anderson
News of an agreement between Facebook and the Israeli government shines a new light on the deactivation of several Palestinian editors' Facebook accounts.
"Having not received a report we aren't sure which Facebook community standard we violated, though I presume the fact we are swearing, wearing latex gloves and suggestively fondling fruit may have something to do with it. I'm not here to say we didn't break any rules; indeed, I don't know if we did because I didn't get an explanation. The thing is, the rules are unreasonable, and inconsistently policed."
Maeve Marsden
On Facebook, French Antiracists Fall Victim to Censorship
Among those affected by Facebook censorship are activists in France fighting against racism.
The morality of social networks: how Facebook censors Trump and female sexuality equally (Spanish only)
Facebook's disappearing act
Marianne Diaz
Takedowns in Venezuela suggest its link-blocking function is used for political speech
...before this when content was removed from Facebook users got a notice saying it had been flagged as inappropriate or that it somehow violated terms of service, indicating that the takedown came from another user's report. Location-based blocking of videos and content for political reasons has usually come from the government via DNS-based blocking or similar practices, never from social media companies themselves.
Marianne Diaz Hernandez
A hard line for hardliners?
Sarah Myers West
Instagram has taken a hard line on Iranian hardliners using the platform.
Facebook's guide to being a lady
A growing number of people are pushing back on double standards in the community guidelines and terms of service for many online platforms.
Between religion and the right to free expression
Arbitrating between religious values and the right to free expression requires a careful balancing act.
If social media companies control both the medium and the message—without oversight or transparency—they take the leap from a being a 'walled garden' to a selectively clear-cut forest.
Social media, news, and the right to know
The idea for Onlinecensorship.org was born in 2011, when Facebook took down a link posted by popular band Coldplay.


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Schools do not exist in isolation. They are based in communities and are there to serve those communities. Some larger schools may serve more than one identifiable community and they therefore need to be aware of any differences in approach that are necessary for each community. Schools provide a service that is available for everyone, which makes them a key resource for children and families in that neighbourhood.
Schools are also part of a network of organizations that provide services and support to communities. Parents can encourage or build on links between the school and the local community. The starting point, as always, is what is important for this school. Schools may already involve some people from the community working in the school alongside parents.
Community venues can often be good places to make contact with parents who may lack confidence in approaching the school or getting involved there. For some parents, school can be rather daunting and it is important to meet people where they feel most comfortable.
Parent Advisory Councils are well placed to make links with other agencies. In particular, they are encouraged to develop links with pre-school and further/higher education establishments to ensure continuity of education for children and young people.
Parents get information from the school about a range of services and activities available in the community.
The school and Parent Advisory Council of elementary schools have positive relationships with the pre-school groups in their community and parents with children at those groups are welcomed at school and parent activities.
Information about the school is available in other community venues, in particular: libraries, and community centres.
Bilingual community members support parents for whom English is not their first language in communicating with the school.
The school uses other community venues for some of its activities, for example swimming pools, sports and leisure centres, theatres and museums.
Local businesses contribute to children's learning by offering visits or work placements and coming to school to talk about their work.
Local shops and businesses support fundraising events or sponsor particular school activities.
The school participates in major community events, for example local celebrations.
Parents at an elementary school decided to tidy up the playground over the summer holidays. This included tidying the woodland garden area during summer break.
They put up a poster in a local shop asking for volunteers as well as sending a note home with the children. The work happened over several weekends and there were many helpers.
The people who took part included a lot of parents who did not have time to help on a regular basis or through the week.
Some older children who were now at secondary school came along to help.
Other people who were not parents came because they were keen to help or because they were friends with one of the parents.
Some people were there on most days.
Others just came for a few hours on one day.
Some people handed in food, so everyone could share sandwiches and home baking each day.
One person took lots of photographs. They were all posted up inside the school and some of the best and funniest went into the window of the local shop with a big thank you sign.
The 'Making the most of your community' activity sets out to identify the resources that are available to support children's learning in the community and to share this information with parents through a community directory or a community learning showcase.
Fundraising has traditionally been an activity that many parent groups have undertaken very successfully over the years and have raised many thousands of dollars to support their children's schools.
In their discussions of the school development plan, Parent Advisory Councils may identify particular items or activities that would benefit from additional funding. There may be discussions about what the priorities are and these can then be checked out with other parents.
Once targets are set, it may be effective to form a fundraising sub-committee. Some parents will have particular talents in that area and it may be a way of involving a wider group of parents to help with specific activities.
Parents, teachers and students are involved in identifying priorities for fundraising and in generating ideas to achieve these.
Different fundraising approaches are used for different purposes.
Local businesses and shops are involved through donations or prizes or sponsorship of appropriate items or activities.
Events and activities appeal to a range of interests and personal budgets - there's something for everyone.
Fundraising events are an opportunity for parents and teachers to work together on a common task and develop positive relationships.
There are fundraising events organised by students linked to educational activities within the school.
Activities follow the three 'Fs' (Fun, Food and Families) formula. Events that provide fun activities for all family members - adults and children - and also provide food are usually the most successful and the ones that people want to come back to again and again.
Parents are able to contribute any particular skills or talents they have.
The school 'piggybacks' on any wider community fundraising events.
As well as a few 'big' events in the year there are some smaller-scale ongoing fundraising events.
Everyone's contribution of effort or money is appreciated - however small.
Success is celebrated and people are thanked.
An elementary school has developed its website with funds from a trust set up by a local company. In return the company gets a mention on the website and some free publicity. This school has also developed a partnership with another firm that has helped the school purchase additional computer and IT equipment.


Time travel is key to Day of the Tentacle Remastered - and not just because it'll hurl you back to 1993, DOTT's original relese date. It'll put your wits against a classic design team's imagination and all-round cleverness.
The humour is surreal, even for LucasArts, with three friends from different eras communicating by way of converted time-machine toilets ('Chron-o-Johns') - they quickly become instrumental in solving oddball puzzles.
You're in this mess because of Dr. Fred, whose Sludge-o-Matic stank up a local river. One mouthful of river gunk later, and a disembodied tentacle grows flippers and decides to take over the world.
Dr. Fred, being as mad as a mad scientist can be, shoves three local teens into Chron-o-Johns, sending them back 24 hours to turn off the sludge machine. Because his kit is powered by a knock-off diamond, though, two chums are flung 200 years off target.
If your head's now swimming a bit, it won't stop on playing the game.
Its weirdness and sense of humour never let up, whether you're helping laid-back geek Bernard explore the present, slovenly roadie Hoagie mooch about in colonial times, or tweaked-out nutcase Laverne survive in a tentacle-ruled dystopian future.
Hoagie's adventures often prove the highlight, not least his interactions with the Founding Fathers and a sarcastic horse (who snarks on a second visit that you're still trying to find your way back to the future).
Beyond amusing dialogue, which you must pay attention to if you want to finish the game, the real stars of DOTT are the puzzles.
They often cleverly use the time travel hook, such as redesigning a flag in the past so it changes in the future, or when you need vinegar but are armed only with wine — before realising what happens when you leave plonk lying around for a few centuries.
The leaps of logic required are sometimes a touch fiendish, though, and this being a reworking of a 20-year-old game, there's no hand-holding.
DOTT is designed so you can't die, but you can easily find yourself wandering aimlessly, head steaming, until you hit upon a brainwave or slink defeated to an online walkthrough.
It's a pity the remastered edition doesn't offer a help system, if only to make this classic more approachable. However, there are concessions to modern gaming.
The graphics have been redrawn and look smart, if a little lacking in texture, the audio is crisp, and the modern controls (tap-hold and select an icon) are leagues ahead of the original's clunky verb-based system.
Issues regarding pace and sometimes bruising logic aside, DOTT manages to remain relevant in remastered form.
This is a game fizzing with personality, style and wit, like an irreverent and expressive TV animation where you get to unpick and master the cartoon logic. And anyone who remembers and loved the original will be thrilled they no longer need their own Chron-o-John to revisit such a pioneering, essential game.
Day of the Tentacle Remastered is available for iOS.
One of the greatest classic point-and-click adventure games is reimagined for iOS in fine form.


text:
Home News Retired UCR Provost Rabenstein faces gender discrimination charges
Retired UCR Provost Rabenstein faces gender discrimination charges
Myles Andrews-Duve
Courtesy of UCR Today
In late 2013 former UC Riverside Chief Campus Counsel Michele Coyle filed a gender discrimination lawsuit against the Regents of the University of California and former UC Riverside Executive Vice Chancellor (EVC) and Provost Dallas M. Rabenstein (2009-2014) in the Los Angeles Superior Court.
After being refiled in the Riverside Superior Court in March of 2015, the hearing began on Friday, Dec. 16, 2016 in a courtroom overseen by Judge John W. Vineyard.
The pleading, which was obtained by the Highlander, shows Rabenstein has been charged by Coyle for retaliation in violation of Labor Code 1102.5 and the fair employment and housing act, harassment and failure to prevent harassment, discrimination and retaliation.
According to the document, Rabenstein, the second-highest ranked administrator at UCR at the time, is accused of engaging "in rampant gender discrimination against female employees" from 2010 up until Coyle's termination in 2012.
Coyle claims to have made multiple demands that the UCR administration and UC Regents "make efforts to remedy the hostile work environment and discriminatory culture on UCR's campus," per the pleading, but suggests that Rabenstein's colleagues (former UCR Chancellor Timothy White, UC General Counselman and Vice President Charles Robinson and former UC Senior Counselman David Birnbaum) failed to address her complaints and rather "ratified his repugnant behavior."
Additionally, the pleading claims that Coyle's refusal to comply with the defendant's alleged "cover-up" led to her termination in 2012.
The alleged cover-up, according to section C of the pleading, was mostly initiated when, during the fall of 2012, the Department of Labor's Office of Federal Contract Compliance Programs (OFCCP) scheduled an audit to "evaluate UCR's compliance with affirmative action regulations and equal opportunity compliance laws." With the audit looming, Rabenstein allegedly refused to fund analysis of faculty compensation data and rather chose to mischaracterize data from previous years. The pleading further claims that Rabenstein guided employees he oversaw to "suppress and misrepresent" accurate data. This included Coyle, whom he allegedly threatened with consequences if she attempted to obtain funding for accurate data.
Not long after Coyle went forward with requesting funds from White, she was terminated. According to the document, Coyle believes "such analyses would have revealed illegal inequalities in compensation based on gender that had not been remedied due to Rabenstein's discrimination and Defendants' failure to remedy it."
Rather than addressing Coyle's accusations, defendants fostered what the pleading deemed "an old boys' club mentality" within the work environment. According to the document, some examples of the defendants' alleged discriminatory conduct include:
White regularly making sexist comments toward female coworkers (sic) and staff in the workplace;
White hiring a man over two equally qualified women for a leadership position because of his personal preference for men in leadership positions and admitting this rationale to a recruiting committee;
White regularly telling women who complained of discrimination by Rabenstein that they would be "better appreciated" elsewhere;
Birnbaum continually referring to women, including Coyle, and to victims of harassment who testified at administrative hearings as "overly emotional";
Birnbaum continually referring to Coyle as "just a complainer" for raising complaints to him about Rabenstein's gender discrimination and retaliation; and
Robinson mocking victims of harassment, including Coyle, blaming them for having a "victim mentality" and for their "poor judgement" in raising claims of discrimination and retaliation.
The case hearing, for which the plaintiff hearing concluded on Thursday, Jan. 19, begins its sixth week on Monday, Jan. 23. During the plaintiff hearing, two UCR professors, the former UCR ombudsperson and former Assistant Vice Chancellor for Diversity, Equity and Excellence Dr. Yolanda Moses all testified in support of Coyle's claims of retaliation and the defendants' failure to address and independently investigate complaints by women on the UCR campus of harassment and discrimination by senior leadership.
Speaking on the case, UCR campus spokesman James Grant offered in a statement, "The trial is proceeding against the Regents only. There are currently no individually named defendants, including former UCR Chancellor White or former UCR Provost Rabenstein. The University will continue to vigorously defend the allegations in this matter, but does not as a matter of practice comment during the pendency of litigation."
Rabenstein spent 29 years at UCR as a distinguished professor of chemistry and was hired as EVC and provost in 2009. Prior to his retirement in June 2014, UCR began the Dallas L. Rabenstein Endowed Fund for Chemistry aimed to support an annual lecture series and assist UCR students and faculty in the chemistry department.
Coyle was hired as UCR's first chief campus counsel in 2006 by then-Chancellor White. In her position she advised senior leadership on the rights, responsibilities and legal requirements of UCR. Prior to being hired, Coyle held an extensive background working in employment law and internal investigations and, according the the pleading, "was hired specifically to tackle long-term campus problems of harassment, discrimination and hostile work environment."
Coyle was replaced in October 2012 by current Chief Campus Counsel David E. Bergquist who formerly served as senior campus counsel and senior counsel at UCSF and the Office of the General Counsel since 2002.
The case is taking place every week in the Riverside Superior Court in courtroom seven from Monday thru Thursday. The witness testimony begins at 10 a.m. with a break at noon before starting again at 2 p.m. Attendance is open to the public.
UC Riverside faculty demographics by the numbers:
According the the academic file control reports published by the UC office of the president, UCR's faculty saw 20 women brought forth as new appointments between the years of 2009 and 2012 when Rabenstein served as provost.
Meanwhile, 36 men were newly appointed at UCR over that same span.
The 20 women appointments accounted for around 38 percent of the campus' new appointments, right in line with the UC-wide average between 2009 and 2012.
The number of women appointments at UCR saw a dip of nearly 20 percent between the 2010-11 and 2011-12 academic years.
The Highlander is still awaiting comment from White, Robinson and Birnbaum.
chancellor white
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The benefit of our work became apparent on Tuesday, March 24, as the high tide washed against the derelict bulkheads that once protected this road south out of Fortescue connecting it to Raybin's Beach.
In the clip above Boomer Huen's bulldozer heroically extends the high tide line out against the Delaware Bay waves lap the new shoreline. When horseshoe crabs arrive in May, instead of a bulkhead death trap, they will find a well-defined beach with deep sand to lay their eggs.
Over the last two decades, the town has fought to maintain this beach and road out to its tiny suburb Raybin's Beach, using construction debris as a last resort. Despite this, the small community, active since at least 1932, now looks close to being extinguished by the sea. Our beach-making will write another chapter for the endangered community, but the uncertainty of Delaware Bay coastal planning leaves open whether there will be more.
The work at Thompson's proceeds slowly but promises more results throughout the week. Wickberg Marine staged its machines on Monday in preparation for beach building on Tuesday. Steve Green removed the old bulkhead boards on the beach, removing a long significant threat to horseshoe crabs. The beach is now ready for sand.
Thompson's Beach bulkhead deadwood readied for disposal.
George Kumar of Maurice River Township tend his gill net off of Thompson's Beach.


text:
\section{Introduction}
Gamma Ray Bursts (GRBs) were serendipitously discovered in late 1960s by the Vela military satellites.
In the following years, dedicated scanning instruments on board high energy missions like \emph{BeppoSAX}\footnote{https://heasarc.gsfc.nasa.gov/docs/sax/sax.html}, \emph{CGRO}\footnote{https://heasarc.gsfc.nasa.gov/docs/cgro/cgro.html}, \emph{HETE}\footnote{
https://heasarc.gsfc.nasa.gov/docs/hete2/hete2.html}, \emph{Swift}\footnote{https://swift.gsfc.nasa.gov/} and \emph{Fermi}\footnote{https://fermi.gsfc.nasa.gov/} have increased the number of GRB detections to several thousands. GRBs are non-recurring events, hinting at underlying catastrophic phenomena.  The gamma-ray flash typically lasts for a few seconds to a few minutes, and in some rare cases to thousands of seconds.

Most GRB detections in the initial decades were made by the \emph{BATSE} instrument on-board \emph{CGRO}. Due to the poor sky localization capacity of \emph{BATSE}, of the order of a few degrees, which is larger than the field of view of typical optical and radio telescopes, scope of longer wavelength follow up observations were limited in this period. Understanding the nature of these sources from unpredictable and short lived $\gamma$-ray emission alone was difficult.
By the launch of \emph{BeppoSAX} in 1996 with a Wide Field Camera (WFC) capable of better angular resolution ($\sim 5$ arc minute) the era of long wavelength counterparts  began \cite{Cota:1997cg}.

The long wavelength ``afterglow emission'' lasts for longer time-scales, a few days in X-rays/Optical to even years in the radio bands. From its beginning two decades ago, afterglow studies have played a pivotal role in the progress of GRB physics. The first milestone was in confirming their cosmological origin \cite{vanParadijs:1997wr}.

In most cases cosmological redshift ($z$) is measured from absorption lines against the bright optical afterglow of a burst or from emission lines from the associated host galaxy \cite{Galama:1997a}. As of now, the closest known burst is $\sim 39$~Mpc away ($z = 0.008$) and the furthest detected one till date is at a redshift of $9.4$ (photometric $z$, \cite{Cucchiara:2011pj}). GRBs are perhaps the cleanest known beacons of the early universe.

In this article, we review the progress made in GRB physics through radio afterglow studies. As of now, radio is the least explored band in the afterglow spectrum, a major reason being the poorer flux sensitivity of the radio instruments compared to Swift XRT or a $1$ to $2$~m class ground based optical telescope. With around $10^4$ seconds of integration, XRT sensitivity reaches around $4 \times 10^{-14}$erg cm$^{-2}$ s$^{-1}$ (reference: Swift XRT instrument page), which after roughly accounting for the bandwidth corresponds to $\sim 10^{-7}$~mJy. A limiting optical magnitude of $23$ in AB system corresponds to $\sim 1\, \mu$~Jy. For comparison, the Very Large Array (VLA) afterglow upper limits before upgradation was $\sim 100$~$\mu$ Jy. However, the Jansky VLA reaches to a few $10$~s of $\mu$ Jy sensitivity with around one hour on source time (ref: several GCN circulars). Therefore, number of radio detections and long follow-up campaigns have already started to increase. In a few years, the high sensitive Square Kilometer Array (SKA) will become operational. Its precursors and pathfinders are starting to be operational, and several existing instruments like the Giant Meter-wave Radio Telescope (GMRT) are undergoing upgradation. In this background, we list a few unique features of afterglow physics radio band alone can probe. There are two good reviews already existing with a similar theme. \cite{granotalexander} provides an extensive review of radio afterglows covering several theoretical and observational prospects. \cite{Chandra:2016tzf} reviews radio afterglows with more observational emphasis than us. We focus more on the theoretical afterglow modelling aspects and take a pedagogical approach throughout.

The review is arranged as follows. In the next section, we will give a brief description of some of the basic concepts in afterglow physics. In section-\ref{class}, we discuss the burst classification and progenitor models. Section-\ref{std} gives an overview of the standard afterglow model. We discuss the most important inferences that could be drawn from the radio band, especially with the support of broad-band modelling, in section-\ref{prob}. We devote section-\ref{q} for recent novel conjectures on potential diversity in radio afterglows. We conclude with a note on how upcoming facilities in radio band will be of importance in GRB physics.
\section{Basic energetics}
\label{basics}
The first step towards building a physical model for GRBs is to form an idea on the energetics involved. Once the luminosity distance $d_L$  is known from $z$, the energy can be estimated from the observed $\gamma$-ray fluence \footnote{Fluence is energy received per unit area.} ($f_{\gamma}$).  Assuming the energy is released isotropically, $E_{\gamma, {\rm iso}} = 4 \pi d_L^2 f_{\gamma}$.  However, the true energy budget will be different if the energy is released anisotropically. Typical values of $E_{\gamma, {\rm iso}}$ varies from $10^{50}$ to $10^{52}$ ergs. In at least one exceptional case, the isotropic energy budget has exceeded the rest energy of a solar mass object (GRB 080916C \cite{Abdo:2009zza}).

The initial $\gamma$-ray flash, also known as prompt emission, is found to vary in milli second time-scale. This indicates, from the light travel time effects, that the emission region is compact ($R < c \delta t$ where $R$ is the size of the region, $c$ is the speed of light, and $\delta t$ is the variability time-scale of the prompt emission), and is of the order of $10^7$~cm. %
The compactness of the emission region, the energy involved in the process, and the typical local rate of $\sim 1 /Gpc^{-3} yr^{-1}$ \cite{Kumar:2014upa} indicate that Gamma Ray Bursts may originate in the gravitational collapse leading to the formation of stellar mass black-holes.

Confining MeV gamma-rays in a compact volume of $\sim 10^{22}$~cm$^3$ will lead to a plasma that is optically thick to pair production, which in turn will produce a thermal spectrum in soft gamma-rays. However, the prompt emission spectrum is predominantly non-thermal. This paradox, known as the \textit{compactness problem}, could only be resolved by invoking a relativistically expanding source, a hypothesis proved right through radio afterglow observations (see section-\ref{scintil}).

\section{Burst classification and progenitor models}
\label{class}
During the \emph{BATSE} period itself, GRBs were found to fall in a bimodal distribution in the spectral and temporal characteristics of the prompt emission: short duration bursts with relatively harder $\gamma$-ray spectrum and  longer duration ones with a softer spectrum \cite{Kouveliotou:1993yx}. In the BATSE band, the long-short distinction is set at a $T_{90}$ of $2$~seconds. $T_{90}$ of a burst is the duration in which $5$\% to $90$\% of the total counts are emitted. However, since the burst duration is a function of the energy band in which it is observed, this value is detector dependent. The observed duration is also a function of redshift due to cosmological time dilation, and an intrinsically short burst  at high $z$ can be mis-identified as a long burst \cite{Zhang:2009uf}.
Recently, a new class of bursts known as ultra-long bursts, which have thousands of seconds of duration, have been discovered \cite{Levan:2013gcz}. Though there are attempts to bring in a physically motivated classification scheme \cite{Zhang:2006mb}, by and large the long-soft and short-hard classification is followed.

In both long and short bursts, almost similar amount of energy (within two or three orders of magnitude) is released in a $\gamma$-ray flash, laden with milli-second scale random variabilities. The outflow that generates both kind of flashes has to be relativistic (see compactness problem mentioned in the previous section), which means the energy per baryon mass ($E/M_{\rm ej} c^2) \gg 1$. Yet, there is a distinction in the duration of prompt emission between long and short bursts. This indicates that while there are similarities in the way the $\gamma$-ray flashes are produced, the progenitors are likely to be different between the two classes.

Hence the current understanding is that the central engine that powers both the long and short bursts could be similar, but they might originate from two different channels. A black-hole torus system \cite{Woosley:1993wj} or a milli-second magnetar \cite{Usov:1992zd} are proposed for the central engine - the only two possibilities where $10^{50}$ to $10^{52}$~ergs of energy could be efficiently extracted. Since the burst duration is an indication of the life time of the jet emanating from the central engine,  long bursts need to have a more massive torus.  Hence long bursts are suggested to be due to the gravitational collapse of a massive star ($M > 15M_{\odot}$)  to a black hole \cite{Woosley:1993wj} while the short ones are believed to be originating from the merger of double neutron star binaries or neutron star - black hole (NS-BH) binaries \cite{Eichler:1989ve}.

Further observations of the afterglow and host galaxies have provided supporting evidences for the above progenitor hypothesis. In a few nearby long bursts, the featureless blue continuum of the optical afterglow emission was found to give way to the redder supernova spectrum (stripped envelope type-Ic) rich with emission lines \cite{Galama:1998ea, Hjorth:2003jt}. This association of long GRBs with core collapse supernovae is the strongest support for the massive star progenitor model. Multi-messenger astronomy with gravitational wave and electromagnetic detectors is expected to soon unravel the association of short bursts and compact object mergers.

\section{Standard fireball model: fundamental layout}
\label{std}
Years of multi-wavelength observations and theoretical developments have laid a solid foundation of the standard fireball model, according to which the Gamma Ray Burst originates in a collimated relativistic outflow (jet) launched by a central engine: either a black-hole torus system or a fast rotating highly magnetized neutron star (milli-second magnetar). Unlike outflows which are imaged (for example, AGN jets or protostellar jets) collimation is an indirect inference for GRBs (see section-\ref{jet}).

The jet energy is dissipated and radiated away in two phases. An internal dissipation either through shocks or magnetic reconnection leads to the prompt emission \cite{Narayan:1992iy, Usov:1992zd}. This occurs at a distance of around $10^{12} - 10^{14}$~cm from the center. The jet subsequently moves forward and plunges into the external medium surrounding the burster, launching a relativistic shock that generates the afterglow radiation. Along with the relativistic forward shock, for baryonic ejecta, there can also be a reverse shock moving to the ejected material. This reverse-forward shock system is dynamically coupled. Below, we discuss the dynamics of the forward shock. See section-\ref{RS} for more details of the reverse shock.

\subsection{Dynamics of the forward shock}
\label{FS}
The swept up material, which is accumulated in the downstream of the forward shock, is heated up to relativistic temperatures. Random motion Lorentz factors of protons in the downstream is roughly equivalent to the bulk Lorentz factor of the shock. When the mass equivalent of the downstream thermal energy, $\Gamma_0 m_{\rm sw}$ (where $\Gamma_0$ is the initial bulk Lorentz factor of the outflow and $m_{\rm sw}$ the rest mass of the swept-up material), approaches the ejected mass ($M_{\rm ej} = E_k/\Gamma_0 c^2$, where $E_k$ is the kinetic energy of the ejected material) the shock starts to decelerate. The observer frame time $t_{\rm dec}$ corresponding to the deceleration radius ($r_{\rm dec}$) is $\sim r_{\rm dec}/(2 \Gamma_0^2 c)$.

In the simplistic form of the afterglow model, the forward shock dynamics is divided into four phases, separated by three observer frame epochs. First one is $t_{\rm dec}$ mentioned above, before which the fireball moves with constant velocity ($\Gamma = \Gamma_0$). In the post-deceleration relativistic phase, $\Gamma(r)$ follows the self-similar Blandford - McKee dynamics \cite{Blandford:1976uq}, where $\Gamma(r) \propto r^{-g}$  and the value of the scaling index $g$ is decided by the radial density profile of the ambient medium and the downstream energy loss rate (adiabatic vs radiative fireball). The third phase beginning with the jet break time $t_j$ is explained below. The fireball finally evolves into the non-relativistic phase at $t_{\rm nr}$ and asymptotically attains the self-similar Sedov-Taylor dynamics.

\subsubsection{Jet effects in the afterglow dynamics}
\label{jet}
As the shock decelerates, the bulk Lorentz factor $\Gamma (r)$ drops down and at some point it becomes comparable to $1/\theta_j$, where $\theta_j$ is the initial half-opening angle of the jet. According to simple analytical models \cite{Rhoads:1999wm}, dynamical effects due to the lateral spreading of the jet becomes dominant roughly at this epoch. At the corresponding observer frame time, called the jet-break time ($t_j$), afterglow lightcurve decay is expected to steepen achromatically. Numerical hydrodynamic simulations by \cite{vanEerten:2010mm} found that (i) a logarithmic spreading to be more appropriate (i.e., a nearly non-spreading jet) and (ii) jet break is chromatic in radio frequencies which are optically thick. Further simulations by \cite{Wygoda:2011vu} on the other hand found lateral expansion is important when $\Gamma$ goes below $1/\theta_j$, but only for narrow jets (jets with $\theta_j < \sim 12\deg$).

It is to be pointed out that even if there are no dynamical effects (i.e., a non-spreading jet), jet signature appears in afterglow lightcurves through relativistic effects. Due to relativistic beaming, the observer only sees a $1/\Gamma$ cone of the jet. When $1/\Gamma > \theta_j$, i.e., when $\Gamma$ goes below $1/\theta_j$, the observer starts to see the edge of the jet. The lightcurve decay rate increases even in this case, but the steepening is of a lesser magnitude than that of a spreading jet where dynamics also changes.

However, data of many well observed afterglows are not consistent with the predicted sharp achromatic break from analytical calculations even at higher frequencies \cite{Liang:2007rn, Racusin:2008bx}. Though part of the reason could be poor sampling, extensive broad-band modelling of well sampled lightcurves is required to understand the dynamics of GRB jets.

The three observer-frame epochs,  deceleration time ($t_{\rm dec}$), jet break time ($t_j$), and non-relativistic transition time ($t_{\rm nr}$), demarcating the four phases of fireball dynamics depend only on the isotropic kinetic energy $E_k$, ambient density, and the initial half-opening angle $\theta_j$ of the jet. Additional parameters of the problem appear from synchrotron physics.

\subsection{Afterglow spectrum}
\label{spec}
The afterglow spectrum emanates from the shock downstream, where electrons are accelerated to a non-thermal power-law distribution, and magnetic field is enhanced. These electrons radiate predominantly via the synchrotron process. The synchrotron flux depends on the fraction $\epsilon_e$ of the shock thermal energy in power-law electrons, the fraction $\epsilon_B$ in downstream magnetic field, and the electron energy distribution index $p$. If the fractional energy content in the downstream magnetic field is much higher than that in the electron population, synchrotron self-Compton (SSC) emission may also become important. However, we ignore this process in the rest of this review.

The instantaneous synchrotron spectrum is defined by three spectral breaks: (i) frequency $\nu_m$ corresponding to the lowest electron Lorentz factor $\gamma_m$ of the injected electron distribution, (ii) the cooling break $\nu_c$ corresponding to the electron Lorentz factor $\gamma_c$ above which radiative losses are severe, and (iii) the self-absorption frequency $\nu_a$ below which the fireball is optically thick to synchrotron self-absorption. The fourth and final parameter characterizing the instantaneous spectrum is the flux normalization $f_m$. This is the spectral peak at a given time, and it appears at min($\gamma_m, \gamma_c$). Readers interested in deriving these spectral parameters can refer \cite{Wijers:1998st}. Figure-\ref{speclc} (left) gives an example spectrum. There is a unique, but coupled, mapping between the spectral parameters $\nu_m, \nu_c, \nu_a$, $f_m$ and the physical parameters $E_k, n, \epsilon_e, \epsilon_B$ (each spectral parameter depends on at least $3$ if not all of the physical parameters). Hence, broad-band modelling is necessary to faithfully infer the physical parameters of the emission region (in the ideal condition, the spectral index $p$ can be measured directly from the spectrum, however this can often get complicated due to poor data sampling and absorption due to the host galaxy gas and dust column).

As the shock slows down, downstream thermal energy density goes down. All four spectral parameters mentioned above, characterising the instantaneous spectrum, depend on the downstream thermal energy density. Therefore, the synchrotron spectrum evolves in time resulting in a time varying flux in all wavelengths (see figure-\ref{speclc} (right)).  Generally, the flux at a given observer frame time $t$ and a given frequency $\nu$ can be written as $f(\nu, t) \propto \nu^{-\beta}  t^{-\alpha}$, where $\beta$ is decided by the particular spectral regime $\nu$ falls in and $\alpha$ depends on both the spectral as well as dynamical regimes discussed above. See this recent review \cite{Kumar:2014upa} for a detailed description of the theoretical framework of the fireball model.

Emission from the reverse shock is seen in the early optical and radio afterglows. We will discuss this next.

\begin{figure*}
\begin{center}
\includegraphics[scale=0.3]{slowcool_spec_SPN.pdf}
\includegraphics[scale=0.3]{lowfreq_lc_spn.pdf}
\caption{Standard fireball model in its bare-bone version. (Left:) The instantaneous synchrotron spectrum and (right: ) low frequency lightcurve. Reproduced from \cite{Sari:1997qe}.}
\label{speclc}
\end{center}
\end{figure*}
\subsection{Reverse shock emission}
\label{RS}
Apart from the forward shock, a reverse shock also forms if the ejecta from the central engine is baryonic. The reverse shock (RS) moves into the ejecta itself. The shocked ejecta and shocked ambient medium are separated by a contact discontinuity (see figure-\ref{sketch} for a sketch). Dynamics of both shocks are coupled. The reverse shock starts off with non-relativistic velocities and turns mildly relativistic if the ejected shell is thick enough. Simplistic calculations hence consider RS dynamics in two asymptotic regimes: Newtonian RS (thin shell) and relativistic RS (thick shell) \cite{Meszaros:1999kv, Sari:1999kj, Kobayashi:2000af}. Thin and thick here refer to the physical width of the ejected shell, not to be confused with self-absorption (or the lack thereof) that makes the RS downstream optically thick (or thin).  Newtonian RS crosses the ejected shell at the deceleration epoch $t_{\rm dec}$ described in section-\ref{FS}. For relativistic RS shock-crossing occurs at $\sim T_{90}$. Dynamics of the Newtonian RS depends on the initial bulk Lorentz factor $\Gamma_0$ of the ejecta, in addition to $E_k$ and number density of the ambient medium. For relativistic RS, one more additional parameter, $T_{90}$, representing the width of the ejected shell, enters the picture. For a detailed review, see \cite{Gao:2015lga}.
\begin{figure}
\begin{center}
\includegraphics[scale=0.4]{media_sketch.pdf}
\caption{The reverse forward shock system, separated by a contact discontinuity (CD). Arrows indicating directions of the shocks are w.r.t to the rest-frame of the CD. With respect to the observer, the entire system is moving towards her in relativistic velocities. Differing heights of each region represents the co-moving number densities.}
\label{sketch}
\end{center}
\end{figure}
Synchrotron spectrum from the reverse shocked ejecta can be calculated from the properties of the downstream the same way as described for the FS in section-\ref{spec}. Reverse shock emission appears in lower frequencies compared to the forward shock. This is because its upstream, the ejected matter, is denser than the ambient medium, the upstream of the forward shock. Hence  the average kinetic energy of the accelerated electrons is smaller compared to that of the forward shock, and thereby the synchrotron spectral peak shifts to lower frequencies.

Along with the parameters required to explain RS dynamics ($E_k$, ambient density, and $\Gamma_0$ for Newtonian RS, and additional $T_{90}$ for relativistic RS), three more parameters representing the RS downstream micro-physics will complete the full set required to explain the spectral evolution. These are: the fractional energy in non-thermal electrons and magnetic field, ${\epsilon_e}^{\rm RS}$ and ${\epsilon_B}^{\rm RS}$ respectively, and the electron index $p$ in the RS downstream. Time evolution of the RS downstream thermal energy density, number density, and bulk velocity will be different from that of the FS, making its lightcurves to appear quite different from that of FS.

Temporal peak of the optically thin reverse shock lightcurve (optical/IR/mm) occurs when the shock crosses the ejected shell \cite{Sari:1999kj}. RS peak can hence be used as a probe of $\Gamma_0$ within this simple framework. Since the ejected material is a shell of finite width, optically thin reverse shock emission does not last for a very long time after the shock crosses the shell. Hence RS emission in optical/IR/mm often appears as a fast decaying component in the early afterglow \cite{Sari:1999iz}.

Standard RS calculation that we described above assumes pressure equilibrium at the contact discontinuity. However, if the RS is long-lived, this assumption breaks down. See \cite{Uhm:2010js} for a formalism that relaxes this approximation.

\subsection{Deviations from standard model}
Though the standard model treats the prompt emission (internal dissipation) and afterglow (external dissipation) as two separate phases, in reality the border is diffuse. In the basic standard model described above, afterglow calculations are done assuming a single shot of energy deposition in the external medium. However, early X-ray lightcurves from \emph{Swift} revealed that the reality is far from this. In majority of GRBs the central engine appears to inject additional energy in a continuous manner to the already decelerating external shock for a few hundreds of seconds \cite{Nousek:2005fm}. In addition to that in some cases the early afterglow is influenced by spasmodic late energy supply from the central engine appearing in the form of X-ray flares \cite{Burrows:2005ww}. Several authors have incorporated a continuously powered fireball in theoretical afterglow calculations \cite{ZhangMesz:2001, Panaitescu:2005nq, gulli:2006}.

Another major discrepancy between the standard model and observations is in jet breaks (see section-\ref{jet}).

Furthermore, many well observed afterglows show a far more complex evolution than what is described in the standard model. Additional emission components like a wider jet or cocoon are commonly invoked to explain the full evolution of a single well observed burst \cite{Resmi:2012dz} (see figure-\ref{0525afig}). There are also bursts that do not adhere to the simplified version of synchrotron theory and requires various modifications, for example, a time dependent micro-physics of the shock downstream. One good example is the well observed GRB 130427a \cite{Panaitescu:2013pga}.

A uniform top-hat jet, where the jet Lorentz factor and emissivity are uniform within a cone of rigid edges, is assumed in the most commonly used standard model calculations. However, in reality, the jet could be structured with an angular dependence for the above parameters \cite{Meszaros:1997je, Zhang:2001qt}. Afterglows emanating from such a jet definitely will deviate from model predictions assuming a uniform top-hat jet.
\begin{figure
\begin{center}
\includegraphics[scale=0.4]{050525a_twojet.pdf}
\caption{An example of broad-band modelling from \cite{Resmi:2012dz}. Here, a two component jet model is used to explain the afterglow evolution.}
\label{0525afig}
\end{center}
\end{figure}

To summarise, broadband spectral evolution of GRB afterglows can shed light onto the energetics of the explosion, nature of the ambient medium, structure of the jet, and the micro-physics of the shocks. Though a complete understanding requires dense sampling of the multi-wavelength data, in the next section we focus on some of the questions radio afterglows are specifically equipped to address.
\section{Probing GRB physics through associated radio emission}
\label{prob}
First observation of a radio afterglow was in 1997 for GRB970508  by the Very Large Array (VLA) \cite{Frail:1997qf}.  Since then radio observations have played a unique role towards the development of GRB physics.

We will first discuss one of the important milestones radio observations could achieve - the evidence for relativistic motion. In the remaining three subsections, we will describe three potentially promising avenues to explore with high sensitivity next-generation radio facilities.
\subsection{Inferring relativistic motion through radio observations}
\label{scintil}
As mentioned in section-\ref{basics}, relativistic motion was proposed to resolve the compactness problem. It was radio observations that finally proved the hypothesis.

The radio afterglow of GRB970508 showed strong (r.m.s variation $\sim 0.8$ mean flux) and rapid ($\delta t < 5$ hr) variability for the initial few weeks \cite{Frail:1997qf}. These fluctuations were also chromatic, i.e., uncorrelated between $4.8$ and $8.4$~GHz radio frequencies. The chromaticity can be seen through the variation of the spectral index $\beta$ of (where the flux $f_{\nu} \propto \nu^{\beta}$) between $4.8$ and $8.4$~GHz frequencies. Such rapid, strong and chromatic variability evidently points to diffractive scintillation, which occurs when rays are diffracted by small scale irregularities of the ionized medium they travel through \cite{Goodman:1997yf}. These rays interfere and cause strong flux modulations. But this occurs only when the source angular size is smaller than the characteristic size of the irregularities in the local ISM. Hence, only very compact sources show diffractive scintillation.

After around $40$ days, the variability died down for GRB9705058 and the afterglow began to follow a smooth decay, indicating an increase in source size beyond the threshold for diffractive scintillation by Milky Way's ISM. This served as an evidence of the relativistic motion proposed to resolve the compactness problem (see figure-\ref{scintifig}).

\begin{figure*
\begin{center}
\includegraphics[scale=0.22,angle=270]{grb970508_scintillation_nature.pdf}
\includegraphics[scale=0.22,angle=270.]{scintillation_beta.pdf}
\caption{The scintillating radio afterglow of GRB 970508. (left) Early ($< 30$~day) oscillations in $8$~GHz flux indicating diffractive scintillation, that switches off once the source size crosses a threshold (reproduced from \cite{Frail:1997qf}). (right) The $4 -- 8$~GHz spectrum of the afterglow (reproduced from \cite{Frail:1999hk}). We can see the spectral index variation drastically reduces around $40$ days, confirming the diffractive scintillation hypothesis.}
\label{scintifig}
\end{center}
\end{figure*}
However, it was only a matter of time that a direct observation of relativistic motion was possible, once again in the radio band. For the bright nearby ($z = 0.16$, at a luminosity distance of $580$~Mpc) GRB030329, angular size evolution could be obtained through Very Large Baseline Interferometry (VLBI) and tested against models \cite{Taylor:2004wd} (see figure-\ref{vlbifig}). This once again confirmed relativistic bulk motion in GRBs. However, VLBI studies are possible only for bright afterglows.
\begin{figure
\begin{center}
\includegraphics[scale=0.3]{030329_angsize_Taylor.pdf}
\caption{Angular size evolution of the radio afterglow of GRB 030329 from VLBI. Reproduced from \cite{Taylor:2004ru}. }
\label{vlbifig}
\end{center}
\end{figure}

Compared to afterglow detections in X-ray and optical frequencies, radio afterglow detection statistics is the lowest \cite{Chandra:2011fp}. Upcoming high sensitive radio facilities, including the currently operational JVLA and upgraded-GMRT, can increase the number of radio detections.
\subsection{Radio reverse shock emission: ejecta magnetization and ambient medium}
Quick and sensitive follow-up observations of the JVLA has recently enabled detection of bright early radio emission, for example from GRB 130427a and GRB160509a, possibly from the reverse shock.

In radio frequencies, since self-absorption effects are important, characteristics of the reverse shock lightcurve are different from that of the optically thin lightcurve. \cite{Resmi:2016lmn} calculated the self-absorbed RS emission and estimated the detectability of the RS component as a function of varying physical parameters. They found that low frequency radio reverse shock emission is enhanced by low ambient density (see figure-\ref{RSfig2}). This is a consequence of reduced optical depth in the RS downstream due to increased ejecta spreading. For low ambient densities, delayed shock-crossing gives sufficient time for the ejecta to spread and rarefy itself.

The reverse shock (RS), for which the ejected material itself is the upstream, is an excellent probe to the central engine, especially its magnetization \cite{Zhang:2004ie, Fan:2004ka}. Moderate magnetization, ${\cal{R}}_B = {\epsilon_B}^{RS}/{\epsilon_B}^{FS} \sim$ $10$ -- $100$, is found to enhance the optical reverse shock emission \cite{Jin:2007uf}. However, increasing ${\cal{R}}_B$ does not increase the radio reverse shock flux, due mostly to self-absorption effects \cite{Resmi:2016lmn}. However, the radio reverse shock lightcurve peak, which occurs when the fireball becomes optically thin, is sensitive to ${\cal{R}}_B$. Ejecta magnetization can be uniquely probed with early optical and radio reverse shock observations. See figure-\ref{RSfig} for radio RS predictions for different parameter sets.

\cite{Resmi:2016lmn} also saw that for typical parameters, unless the ambient medium density is extremely low, the RS never outshines the FS in radio frequencies below $\sim 1 GHz$.
\begin{figure
\begin{center}
\includegraphics[scale=0.3]{chiplot_thickw.pdf}
\caption{Ratio $\chi$ of reverse to forward shock flux at the time of the reverse shock peak, as a function of the observing frequency. RS is very unlikely to dominate in low radio frequencies. Different colors represent different set of physical parameters. Notice the sensitivity of $\chi$ to ambient medium density. A wind driven density profile is assumed in this calculation. Reproduced from \cite{Resmi:2016lmn}.}
\label{RSfig2}
\end{center}
\end{figure}
\begin{figure*
\begin{center}
\includegraphics[scale=0.4]{thinismz122GHz.pdf}
\includegraphics[scale=0.4]{thinismz1150MHz.pdf}
\includegraphics[scale=0.4]{thickwindz122GHz.pdf}
\includegraphics[scale=0.4]{thickwindz1150MHz.pdf}
\caption{Radio reverse shock calculations from \cite{Resmi:2016lmn}. The top panel is for a homogeneous ambient medium and the bottom panel for a wind driven stratified ambient medium. One can see that higher ${\cal R}_B$ delays the reverse shock peak, and that the reverse shock does not dominate in MHz radio frequencies for standard range of parameters.}
\label{RSfig}
\end{center}
\end{figure*}
\subsection{Non-relativistic afterglow}
\label{NR}
A singular feature of radio frequencies is that the fireball remains visible for months to years. The text book example is the radio bright GRB030329, which was the first burst observed in MHz radio frequencies. See the radio image of the afterglow around four months since burst by GMRT in figure-\ref{gmrtmap}.  The radio afterglow was observed for more than 5 years with GMRT in $1280$ and $610$~MHz frequencies (see figure-\ref{0329lcfig} for the lightcurve). In these time scales, the shock dynamics changes to non-relativistic velocities, a regime probed in detail only in three GRBs so far \cite{Berger:2004rn, vanderHorst:2007ir}. Single epoch radio observations post $\sim 100$ days are available for around two dozen bursts \cite{Shivvers:2011uj}. Under the assumption that the outflow becomes spherical, energy estimates done in these time-scales are free from the uncertainties in the jet opening angle, unlike broad-band modelling concentrating on the earlier phases. The total (calorimetric) energy in the explosion can be measured and it may allow differentiating between models of central engine of GRBs (magnetar vs black-hole powered) \cite{Wygoda:2011vu}. Thereby, bright radio afterglows provide a unique angle to probe the GRB energetics and central engine.

However, Calorimetric estimates can be affected by two factors : (i) non-spherical geometry in the outflow, (ii) off-axis observer.
\cite{Wygoda:2011vu} found that the difference in energy estimates due to non-spherical geometry in calorimetry is negligible. However, off-axis observers ($\theta_v \gg \theta_j$, who miss the burst itself) may find calorimetric measurements to be significantly different from the true energetics.
\begin{figure*
\label{gmrtmap}
\begin{center}
\includegraphics[scale=0.3]{28JUN04_crop.pdf}
\includegraphics[scale=0.3]{27JUN04_crop.pdf}
\caption{Radio continuum maps of GRB 030329 in $1280$MHz (left) and $610$~MHz (right). These observations are at $117$ and $116$ days post the burst respectively.}
\label{gmrtmap}
\end{center}
\end{figure*}
\begin{figure
\label{0329lcfig}
\begin{center}
\includegraphics[scale=1]{030329_lowfreq.pdf}
\caption{Low radio frequency lightcurves of GRB030329 reproduced from \cite{vanderHorst:2007ir}.}
\end{center}
\end{figure}

Another feature expected in the non-relativistic phase is the emergence of the counter-jet \cite{Li:2004tu}. Assuming the central engine produces a bipolar relativistic outflow, emission from the jet that moved away from the observer never appears until the relativistic de-boosting is lifted off. As the fireball becomes non-relativistic, photons from the counter-jet (CJ) arrives to the observer after travelling an additional $2 R$ distance (where $R$ is the radius of the fireball at the time of emission) compared to the photons from the forward moving jet. Hence the CJ photons at a given observed time will correspond to an emission time earlier than that of the forward moving jet. Since the jet rest-frame emissivity decreases with time, assuming identical emissivities for both jets, the counter-jet when emerges should be brighter than the forward jet, and appears as a bump above the forward jet lightcurve as per analytical calculations \cite{Li:2004tu}.  There has so far been only one burst, GRB 030329, where the CJ emission could be searched for. However, no conclusive evidence is seen in late time GMRT observations \cite{vanderHorst:2007ir}. However, numerical hydrodynamical simulations show that the CJ emission never emerges above that of the forward jet, however appears as an excess emission for hard-edged jets \cite{cjsimln} \ref{boxfitfig}. In the era of SKA where prolonged radio follow-up will be possible, contribution from the counter-jet should be detectable. Using CJ emission, the ambient medium density structure and the jet structure can be modelled in detail \cite{cjsimln}.
\begin{figure
\label{boxfitfig}
\begin{center}
\includegraphics[scale=0.3]{plot_radio_cj.pdf}
\caption{Late radio lightcurves ($5$~GHz) for two different densities of the homogenous ambient medium ($0.1$ and $10$~atom/cc) showing the counter-jet bump. Jet opening angle of $\sim 5$ degrees is used. Produced using the publicly available afterglow numerical hydrodynamical code \emph{BOXFIT} \cite{vanEerten:2011yn}.}
\end{center}
\end{figure}

\subsection{Radio emission associated with short GRBs}
\label{short}
All individual bursts described in the above subsections belong to the long GRB class. Though the same afterglow physics applies to short bursts too, there are very few radio afterglow detections from short GRBs \cite{Fong:2015oha}.

Short bursts have systematically dimmer afterglows in all bands, but from the detection statistics it appears that they are particularly dimmer in radio.  \cite{Fong:2015oha} has a sample of $103$ short bursts observed in the Swift era. X-ray detection statistics is $\sim 69$\%, in optical band it is around $29$\%, and in radio band it is a mere $4$\%. While X-ray and optical detection rates are respectively $1.3$ and $2.5$ times smaller than the total (long \& short) burst sample, the radio statistics of short bursts is an order of magnitude lower.

Radio flux depends on the jet kinetic energy and ambient medium density along with other parameters (see section-\ref{std}). It is important to note that the short bursts have lower isotropic energies. Moreover, compact object mergers are expected to occur in low density environments, owing to the large systemic velocities of the compact binary system arising from their natal kicks. Thus the faint radio emission from short bursts is in accordance with the popular progenitor model.

An exciting conjecture in the context of short bursts is the predicted radio emission from the tidally disrupted neutron star during the merger \cite{Nakar:2011cw}. The amount of mass tidally ejected will depend on the masses and equations of state of the neutron star. According to numerical simulations of binary mergers, the typical mass in this ejecta is $10^{-2}$ -- $10^{-4} M_\odot$, and the velocities are of the order of $0.2 c$ \cite{Hotokezaka:2012ze}. Since the ejecta is mildly relativistic, the deceleration time, which is the typical timescale where the flux peaks, is of the order of years. Moreover, the synchrotron spectral peak will also be in MHz frequencies \cite{Nakar:2011cw}. As the ejecta is nearly spherically symmetric, detection possibilities are better than the jet emission (short GRB) provided the radio signal is bright enough.
There have been a few searches for this emission using the VLA and ATCA \ref{lastfig} \cite{Metzger:2013cka, Horesh:2016dah}.  Unless the ambient density is high enough, current radio facilities are unlikely to detect this emission. A more optimistic possibility is if the merger ejecta is further energized by a central magnetar created from the merger. Thus, upperlimits are used to draw constraints on the presence of a magnetar at the central engine and its energy input to the merger ejecta \cite{Metzger:2013cka, Horesh:2016dah}. Again, high sensitive future instruments operating in lower frequencies has the potential to detect this emission.
\begin{figure
\label{lastfig}
\begin{center}
\includegraphics[scale=0.45]{magnetar_luminosity_E352_eb01_Dec1.pdf}
\caption{Search of non-relativistic merger ejecta from short bursts. Reproduced from \cite{Horesh:2016dah}.}
\end{center}
\end{figure}
\section{Possible diversity in radio afterglows?}
\label{q}
From the statistics of radio observations by VLA till 2011, \cite{Chandra:2011fp} has found that the rate of radio afterglow detections amounts to only 30\% while that of X-ray and optical are around 90\% and 75\% respectively. The lower detection rate of radio AGs is typically attributed to poor detection sensitivity and lack of quick follow up observations \cite{Chandra:2011fp}. The Arcminute Microkelvin Imager Large Array (AMI-LA) operational since 2016 has a quick response but perhaps due to its poor sensitivity, only 15\% of the triggers it responded to so far has resulted in radio detection (statistics from AMI website).

However, there are claims that the low statistics of radio afterglows does not belong to instrumental effects alone but has its roots in an intrinsic diversity in radio afterglows. The conjecture is of two classes of bursts: radio-bright and radio-faint. \cite{Hancock:2013ena} did a visibility stacking analysis using $737$ VLA observations of $178$ GRBs and found that the radio-faint GRBs are not the tail of a single distribution but are a second population less luminous in all wavelengths. They also found that the radio bright GRBs have typically large isotropic energy in $\gamma$-rays.  \cite{Lloyd-Ronning:2016jfr} observed a correlation between radio afterglow signatures and duration of the prompt pulse. According to them, the radio-quiet bursts have intrinsically shorter prompt emission. Both authors hypothesise that the difference is of physical origin. \cite{Hancock:2013ena} suggest that the radio-faint population results from a different central engine or is associated with a different prompt emission mechanism compared to the radio-loud sample. In almost similar lines, \cite{Lloyd-Ronning:2016jfr} suggests that the diversity perhaps is related to burst progenitors. Though an interesting conjecture, this proposed diversity needs to be explored further in detail through deep follow up using high sensitive radio instruments and thorough modelling efforts.
\section{Future of radio afterglow studies}
\label{future}
Though we have studied a large number of Gamma Ray Bursts and afterglows, there are several fundamental questions yet to be fully answered. For example, how collimated is the outflow launched by the central engine? Jet collimation bears important significance in the calculation of the true rate of GRBs and the total energy budget in the explosion. The total energy budget is important in differentiating between different central engine candidates. The leading models for the same are a black-hole torus system and a highly magnetized rapidly spinning neutron star. It is still not clear which is more favoured, or which one of this could be the potential candidate for a given burst. One of the ways to probe this is by studying the early optical and radio afterglows which may carry signatures of the magnetization of the central engine. Another option is to do calorimetry on late afterglow, seen only in radio band, and obtain the energetics of the burst without involving the jet collimation. Both have increasing potential now in the light of upcoming new generation radio telescopes.

Due to the low number of deep and long radio observations, we are yet to know if there exists any major deviations from the standard picture. \cite{Frail:2003nv} has indicated such a possibility. To explore further, radio detection statistics needs to be improved, which is expected in the SKA era.

Emission from merger ejecta expected to be detected in lower radio frequencies will be a unique electromagnetic counterpart to binary compact object mergers, apart from GRB jet emission.

Radio band is the lesser explored part of the Gamma Ray Burst counterpart spectrum. In near future, this picture is going to change and a new set of insights and challenges are expected to emerge.

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Los Angeles Chargers tight end Hunter Henry suffered a torn ACL during a drill Tuesday, according to ESPN's Adam Schefter.
Henry will receive a 2nd opinion on Wednesday after the initial diagnosis showed a torn ACL.
Henry, who suffered the injury during a non-contact sequence, is likely to miss the entire 2018 season, which is a big blow the Chargers' offense.
Los Angeles could look to bring back veteran Antonio Gates to take Henry's place. Gates, 37, has spent his entire career with the Chargers and is currently a free agent.


Today, the Enough Project filed a petition before the African Commission on Human and Peoples' Rights, known as the African Human Rights Commission, against Sudan. The petition alleges that the government of Sudan's indiscriminate aerial bombardment of civilian populations in the states of South Kordofan and Blue Nile, its ground attacks against these populations, and its denial of international humanitarian aid to the two states violate, among other things, the rights to life and property afforded all Sudanese citizens under the African Charter on Human and Peoples' Rights, or the African Charter.
The facts alleged in the petition come within the context of ongoing conflict between the Sudan Armed Forces, or SAF, and government-backed militia, on the one hand, and the Sudan People's Liberation Movement-North, or SPLM-N, on the other, which has engulfed South Kordofan since June 2011 and Blue Nile since September 2011. During this period, not only have the SAF and government-backed militia engaged in battle with the SPLM-N, but they have, as well, purposefully targeted civilian populations through aerial and ground attacks and extra-judicial killings.
More than 366,000 people have been severely affected or internally displaced by the violence since June, while another 140,000 have fled to either Ethiopia or South Sudan. Khartoum's attacks have occurred during harvest and planting seasons, preventing civilians from tending their crops and severely undermining available sources of food in the two states. Compounding these increasingly dire conditions is Khartoum's steadfast refusal to permit international humanitarian aid to reach populations in SPLM-N controlled areas, leaving populations in southern Blue Nile and South Kordofan at emergency levels of food insecurity—one level short of famine.
Enough has transmitted copies of its petition to 11 U.N. Special Rapporteurs, the Independent Expert on the Situation of Human Rights in Sudan, and the U.N. Working Group on People of African Descent requesting that these officials take appropriate actions within their respective competencies, including forming a working group to collectively assess the situation in South Kordofan and Blue Nile.
Yesterday, we remembered the Holocaust and declared, as we have done for nearly 75 years, "never again." In dong so, we must take a critical look at what we have done for the people of Sudan in realizing this declaration. The world has stood by far too long and watched Sudanese officials, such as President Bashir, Defense Minister Hussein, and South Kordofan Governor Haroun, commit heinous crimes against the people of Sudan. While the ICC has issued arrest warrants against these three officials for their roles in crimes committed in Darfur, they continue to commit the same crimes today in South Kordofan and Blue Nile with impunity. Enough's submission of a petition to the African Human Rights Commission is one step towards holding these and other Sudanese government and military officials accountable for their crimes. The international community must, as well, increase efforts to hold Sudanese officials accountable for their violations of international human rights and humanitarian law in Darfur, South Kordofan, Blue Nile, and Abyei.


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Bivariate geometric distribution is an extension to the univariate geometric distribution that models the number of trials to get the rst success. Thus a bivariate distribution can be considered as a model for number of trials to obtain two di erent but related events for the rst time. Many statisticians have studied di erent forms of bivariate geometric distribution. In this thesis, we considered the form which is given by Phatak and Sreehari (1981). We estimated the parameters using maximum likelihood estimation. We derived the deviances as the goodness of t statistics for testing the parameters corresponding to reduced model, generalized linear model (GLM) and the deviance di erence to compare two models in order to determine which model ts the data well. To determine the e ciency of our deviances, we simulated data using computer software R. We found that our deviance for the reduced model with pair of parameters of the bivariate geometric distribution worked well.


The highlight of the year 2018 was not going to places I wanted to go to but rather in search of what might be missing in life. Year 2019, please be kind. Thank you.
An umrah on the exact day I was born 28 years ago.