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Sino-German Center
DFG Office India
DFG Office Japan
DFG Office North America
DFG Office Russia/CIS
DFG Office Latin America
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Home Profile DFG Head Office DFG Representation Abroad DFG Office Russia/CIS News
Reports - Topics - News
2021 - Quarter IV
2021 - Quarter III
2021 - Quarter II
2021 - Quarter I
IV. Quarter 2021
11th German-Russian Week of the Young Researcher – "Internationalisation of Science and Research during the Pandemic"
(25.10.21) At the end of October, the DFG and the German Academic Exchange Service (DAAD) hosted the 11th German-Russian Week of the Young Researcher at the German Centre for Research and Innovation (DWIH Moscow). Discussion focussed mainly on current challenges and the importance of cross-border research cooperation during the pandemic. The event was held as a one-day online conference due to the pandemic, like last year: opened by DFG President Professor Katja Becker and DAAD President Joybrato Mukherjee, it included impulse statements and a panel discussion.
MDZ special issue "Research and Education" 2021
(21.10.21) This year's special supplement issued by the bilingual Moscow German Newspaper (MDZ) on German-Russian cooperation in the field of research and education was published in October 2021. The publication offers locally-based German research, funding and intermediary organisations the opportunity to report on their activities in Russia.
Brochure on the Tenth German-Russian Week of the Young Researcher – "Collaborating Across Borders During the Pandemic"
(05.10.21) For ten years now, the DFG and its Moscow office have organised the "German-Russian Week of the Young Researcher" to focus specifically on bilateral networking and promote early-career researchers in Russia. The 10th anniversary week took place in December 2020 and was dedicated to current challenges facing cross-border research cooperation as well as the new role of science in society at large.
III. Quarter 2021
Message from the DFG President in the journal published by the Russian partner organisation RFBR
(26.07.21) A message from DFG President Katja Becker opens the current issue of the quarterly journal Vestnik published by the Russian Foundation for Basic Research (RFBR), which is dedicated to the 25th anniversary of the partnership between the RFBR and the DFG.
II. Quarter 2021
German Week in St. Petersburg
(27.04.21) The DFG Office Moscow presented the DFG's funding programmes at "#scienceday de-ru" as part of the 18th German Week in St. Petersburg. Involving more than 30 higher education institutions, research institutions and research funding organisations from both Germany and Russia, the week's events provided insights into the current world of research and higher education to more than 500 participants.
I. Quarter 2021
DFG supports higher education and research cooperation between Lower Saxony and Russia
(25.03.21) DFG Office Moscow presented funding opportunities with Russia and ongoing bilateral collaborations between universities and research institutions in Lower Saxony to an audience of over 120. The online meeting on cooperation in the field of "education, higher education and research" was part of the event cycle "Lower Saxony and Russia: Yesterday, Today, Tomorrow", which took place as part of the Year of Germany in Russia in March 2021.
DFG project on art research with exhibition in Moscow
(25.03.21) As part of the current Year of Germany, the exhibition "GAKhN displaced" opened in mid-March with the participation of Ruhr University Bochum, the Goethe-Institut and DFG Office Moscow. The DFG-funded project is dedicated to indexing the estate of the State Academy of Art Sciences (GAChN).
DFG Office Moscow at Workshop on Cluster Formation at Russian Universities
(23.02.21) The Russian "Association of Global Universities" and the German Centre for Research and Innovation (DWIH) Moscow organised a German-Russian exchange involving more than 100 participants on the subject of a new Russian funding programme geared towards promoting the formation of clusters and consortia at universities in Russia. The DWIH and its supporters such as the DFG along with RWTH Aachen University, TU Dortmund University and the Free University of Berlin reported on the funding line and foundation of excellence clusters in Germany.
Curent News by year


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The early history of the Somavamsis
July 2, 2017 by Odisha History
The Somavamsis, other wise known as Panduvamsis, ruled over Odisha from the middle of the ninth century A.D. to the early part of the twelfth century A.D. Initially, in the seventh and eighth centuries A.D., they ruled over a piece of territory, known as Dakhina Kosal or South Kosala (corresponding to the Raipur and Bilaspur districts of Madhya Pradesh and the Sambalpur and Kalahandi districts of Odisha). Sirpur, a place, situated in the Raipur district, was the capital of-the Somavamsis of south Kosala. Udayana was the founder of this dynasty.
Tivaradeva, the fourth king of the line, was its most powerful ruler. He established his sway over the whole of Kosala. In the west he extended his territory as far as the Vindhyas. But in the east his efforts to bring Kangoda within his political sway failed. Tivaradeva ruled from 700 A.D. to 725 A.D. At the dawn of the ninth century A D., Sornavamsi kingdom was invaded by Govindalll, the Rastrakuta king. For sometime, the Somavamsis remained under the hegemony of the Rastrakutas. After the death of Govinda-III in 814 A.D the Somavamsis could emancipate themselves from the hegemony of the Rastrakutas. But, there after they were exposed to the threats of another power, the Kalachuris of Ratnapur (a place in the Bilaspur district of Madhya Pradesh). By the middle of the ninth century A.D. the Somavamsis were seeking eastward expansion most probably because of the Kalachuri menace. The last known king of Somavamsis of south Kosal was Balarjuna Sivagupta who died in 810 A.D. After him, there is a genealogical gap for more than half a century. With the emergence of Janrnejaya-l in the last quarter of the ninth century A.D. we get a regular genealogical line of the Sornavarnsis up to the beginning of the twelfth century A.D. The inscription of Janmejaya-I, the builder of the Somavamsi power in Odisha, mention Sivagupta as his predecessor. The Somavamsi rulers of Odisha were alternatively using two titles – Mahabhavaupta and Mahasivagupta. Besides these facts the same dynastic name strongly suggests that Janmejaya-I was the descendant of the Somavamsis of south Kosala.
There is no such written record regarding the complete history of the Somavamsi rulers and their achievements. However, we get some information from the following inscriptions. The Banda Copper plates of Tivaradeva, Adhavara plates of Mahanannararaja Banda plates of Mahasivagupta; Patna, Kalibhana and other copper plates of Janrneiaya Cuttack, Nibinna and Patna plates of Yayati I; Kalanjar stone inscription, Arang store inscription, Sirpur stone inscription and other inscriptions of the rulers of this dynasty ar the contemporary Bhanja, Bhauma-Kara, Ganda and other inscriptions throw a good dea of light on the achievements of the rulers of this dynasty.
Categories Ancient Odisha Tags The Somavamsis Post navigation
Religion During the Bhaumakaras
Dynastic history and achievements of the Somavamsi rulers

redpajama_set_name: RedPajamaCommonCrawl


Walden University appears in our ranking of the Top 10 Online Master's in Accounting Degree Programs.
Walden University offers a Master of Science in Finance, Bachelor of Science in Accounting, Master of Science in Accounting, and a Graduate Certificate in Managerial Accounting.
The Master of Science in Finance prepares students to meet the rising demand for qualified financial professionals. The program aligns with the needs of the industry and courses are taught by experts in the field. The curriculum implements a practical approach that blends project-based learning, engaging discussions, and case studies. Students gain a comprehensive understanding of the financial field and they acquire specialized abilities needed for certification and careers in various areas, such as corporate finance, financial management, investment banking, securities, government, and other related settings. The program requires the completion of 30 credit hours and it can be finished in as little as 20 months. The core courses include Managerial Finance, Decision-Making Tools for Today's Financial Professional, Analysis and Communication for the Financial Professional, Legal and Ethical Issues in Accounting and Finance, Tax Analysis and Decision Making, Insurance Planning, Financial Budgeting, and Forecasting Analysis, Investment Theory and Portfolio Management, and Retirement and Estate Planning. Students are able to choose from three specializations that focus on specific competencies: Certified Financial Planner, Chartered Financial Analyst, and Finance for the Professional (Self-Designed). The program prepares graduates to take the Chartered Financial Analyst, Certified Financial Planner, and Financial Industry Regulatory Authority qualification examinations.
The Bachelor of Science in Accounting prepares students to enter or advance their career in the accounting field. Students have the option to expand their learning beyond the classroom by participating in field experiences, service learning projects, and study abroad programs. The program offers a General Program and concentration in Public Accountancy to help students achieve their professional and personal objectives. A total of 181 quarter credits are required to complete the program. The core courses include Fundamentals of Accounting, Introduction to Management, Financial Accounting, Business Statistics, Financial Management, Intermediate Accounting, Auditing, and Internal Controls, Accounting Information Systems, Government and Nonprofit Accounting, Managerial Accounting, and Federal Taxation. Graduates are prepared to take the Certified Public Accountant or Certified Management Accounting examinations.
The Master of Science in Accounting helps students advance in the accounting field. Students learn about advanced accounting principles to assist in boosting their analytic and financial decision-making and prepare them to address the accounting challenges in today's business world. Students are able to choose Accounting for the Professional, Accounting with CPA Emphasis, and Self Designed. A total of 30 credit hours are essential for completion of the degree program. The core courses include Business Essentials, Decision-Making Tools for Today's Financial Professional, Analysis and Communication for the Financial Professional, Legal and Ethical Issues in Accounting and Finance, Managerial Accounting for Organizational Performance, and Current Trends in Accounting Standards.
The Graduate Certificate in Managerial Accounting prepares students to effectively manage, evaluate, and communicate sophisticated financial data that impact the performance of organizations. The program focuses on the core content areas of accounting. A total of 12 credits are needed to complete the certificate program. The required courses include Decision-Making Tools for Today's Financial Professional, Analysis and Communication for the Financial Professional, Legal and Ethical Issues in Accounting and Finance, and Managerial Accounting for Organizational Performance.
Walden University is an online, private, for-profit institution of higher education with headquarters in Minneapolis, Minnesota. It was founded in 1970 with the intention of meeting the needs of adult learners. The first degrees were conferred in 1972. The university received accreditation in 1990. The school continued to expand into the 21st century, adding additional programs and colleges. Today, Walden University is home to more than 57,000 students from all 50 states and more than 150 countries. It operates on the quarter based academic calendar.
Walden University is dedicated to helping students achieve their goals and the curriculum keeps abreast the current trends in the fields. Walden offers bachelor's, master's, and doctoral degrees and graduate certificates in a wide range of areas, such as health sciences, management, counseling, criminal justice, psychology, education, nursing, business, and information technology. The programs are offered through the College of Management and Technology, College of Health Sciences, College of Social and Behavioral Changes, Center for General Education, and Riley College of Education and Leadership. Walden University prides itself on its diversity of students, faculty, and staff that work together toward success.
The Higher Learning Commission regionally accredits Walden University to grant bachelor's, master's, and doctoral degrees as well as graduate certificates. The accounting programs at Walden University are accredited by the Accreditation Council for Business Schools and Programs.
The tuition at Walden University depends on specific programs but typically ranges from $325 to $725 per quarter hour.
Walden University offers numerous options for helping students pay for their college education, including scholarships, grants, and loans.
In today's booming economy, finance and accounting professionals are essential to help companies and clients effectively manage financial aspects to ensure optimal function and success of the entity. With the finance and accounting degrees offered by Walden University, students are able to begin or advance their careers in the finance and accounting fields and pursue various positions, such as financial planners, management accountants, government accountants, and public accountant, treasurer, financial analysts.


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Government moves on unit pricing
Jan 11, 2023 | Latest News
MBIE will soon consult the grocery industry on technical details for a unit pricing standard to ensure it works effectively in practice in supermarkets.
Commerce and Consumer Affairs Minister David Clark announced a few days before Christmas that the Government is putting in place rules on unit pricing to make it easier for consumers to compare the price of grocery products.
He said the new rules, which MBIE (the Ministry for Business, Innovation and Employment) will consult on early this year, will require supermarkets, and other large grocery retailers, to "clearly and consistently display unit pricing" – such as the price of a product per kilogram or litre.
The Commerce Commission's market study found though major retailers display unit pricing on many products, it is not consistently used or displayed.
"Our work on unit pricing will help shoppers to compare the prices of similar products and choose the best deal for their needs," Clark says.
"It's particularly helpful where products are sold in different sized packaging and by different brands. We want to make it as easy as possible for Kiwis to use unit pricing in their weekly shop.
"At a time where global factors continue to drive up the cost of living around the world, and high grocery prices are making it hard for New Zealanders right now – our work around unit pricing will mean shoppers can gauge whether something is good bang for buck.
Under the new standard, unit pricing will be mandatory for groceries sold in stores with a floorspace above 1000 square metres. It will also be required in online grocery stores and in some forms of advertising.
"The new rules will mean that around 90 percent of the retail grocery market will need to display prominent, legible unit pricing that is easy for consumers to use. This includes our major grocery retailers, along with new entrants and online retailers, if the thresholds are met. Stores with a smaller footprint, such as dairies, specialist retailers, and international supermarkets, will be excluded from the standard – unless they choose to comply voluntarily.
"Along with helping shoppers to make informed decisions about what they buy, this new standard for unit pricing will also support inter-brand competition and encourage grocery retailers to compete on metrics such as price."


We have listed a new property at 131 Broad ST N in Regina.
This is 131 Broad St North, where a huge 1400+ sq ft 4 level split resides. This home has a few nice upgrades, primarily flooring and some updated windows. The house has been very well maintained, it is clean and needs very few repairs. For the square footage, great price and condition of the home, this is a fantastic opportunity to get into home ownership! There are two large bedrooms and a 4pc bathroom on the top floor, the lower level has a good sized rec room, a large bedroom, and a 2 pc bath. The basement level is exposed concrete, in which you can see 3/4 full 8 ft concrete walls without a single crack (this level is able to be fully developed). This home is SOLID & is close to schools, conveniance stores and the North Gate Mall!


The editorial team of Virtus Interpress is delighted to present first six e-books available for order.
Today more and more people read e-books which offer many benefits and advantages such as: portability (they don't need much space for storage); speed (e-books can be downloaded immediately); price (they are cheaper since there are no printing fees); environmentally friendly (paper-free books save trees).
We are happy to announce that our readers can order e-versions of the books published by Virtus Interpress.
Virtus Interpress intends to provide our network with a possibility to purchase other e-books in the short run. The updates will be available in our news section, stay tuned.


Neal assists with our digital marketing strategy and initiatives. He helps ensure our digital presence is ship shape.
His love of travel and experiencing new places and people started at an early age growing up in a Coast Guard family and moving all over the US; he's lived in ten states and visited 49. He came to the international education field via a happy convergence of his professional experiences in digital marketing, recently with Open Knowledge, an international advocacy group working to improve the use and usefulness of open government data. He's traveled internationally extensively for work and fun.Neal's also been a faculty member at the University of Oregon's Applied Information Management graduate program for over 15 years. Neal's not an artist himself, but enjoys a good show from time to time. His greatest artistic accomplishment to date is having a daughter who picked up guitar playing at an early age without the benefit of any genetic predisposition.


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Q: Creating, Reading from and Deleting Local Files In Windows 8, (for Desktop Apps - Not Metro), how would you go about creating files, writing to them and reading from them?

The following link provides no information about this:
http://msdn.microsoft.com/en-us/library/windows/desktop/hh447209(v=vs.85).aspx
I know how to do it in Metro apps, but where's the documentation?

A: This sounds like you would have the full .NET framework at your disposal, the System.IO.File class should help in that case.

redpajama_set_name: RedPajamaStackExchange


text:
Q: Mass deinterlacing with FFmpeg on Debian I have about 300 videos, on a Debian server, stored in the following manner:
/mediaroot/1/m32.mp4
/mediaroot/2/m421.mp4
/mediaroot/n/mx.mp4

They all need to be deinterlaced, and I want to do it with FFmpeg.
With the assistance of another helpful sole, I have reached a somewhat tolerable result with the following steps:

*

*extract audio

*transcode video, example
ffmpeg -y -i m148.mp4 -pix_fmt yuv420p -an -pass 1 -passlogfile m148.x600.1351896878.log -an -vcodec libx264 -b:v 600k -preset medium -tune film -threads 0 m148.x600.1351896878.mp4
ffmpeg -y -i m148.mp4 -pix_fmt yuv420p -an -pass 2 -passlogfile m148.x600.1351896878.log -an -vcodec libx264 -b:v 600k -preset medium -tune film -threads 0 m148.x600.1351896878.video.mp4

*mux new video with audio extracted in step 1.

*use qt-faststart to move the atoms
ffmpeg/qt-faststart m148.x600.1351896878.mp4 m148.x600.1351896878.atom.mp4

My question is then: How do I make it automatically deinterlace and replace all the videos?

A: Write a simple shell scrip - you basically have everything done already, just need to put it together "under one roof" (in one script file).
#!/bin/bash

# loop over all arguments to the script - place each single
# one into variable f (further referenced to by $f) and execute
# the commands in the loop
for f in "$@"; do
    # create new variable holding filename without the extension
    n=${m%.mp4}

    # commands you mentioned above go here, you only need to
    # replace the strings that correspond to actual filename
    # with "$f" or "$n". Use the quotes around in case your
    # filenames contained spaces. e.g.:
    ffmpeg -y -i "$f" -pix_fmt yuv420p -an -pass 1 -passlogfile "$n".x600.1351896878.log -an -vcodec libx264 -b:v 600k -preset medium -tune film -threads 0 "$n".x600.1351896878.mp4
    ffmpeg -y -i "$f" -pix_fmt yuv420p -an -pass 2 -passlogfile "$n".x600.1351896878.log -an -vcodec libx264 -b:v 600k -preset medium -tune film -threads 0 "$n".x600.1351896878.video.mp4

    # more commands...
done

Then run the script with filenames to convert as its arguments:
script.sh file1.mp4 /another/directory/file2/mp4 ...

You will either need to make it executable: chmod a+x script.sh or run it through the shell interpreter explicitely: bash script.sh ...

A: To deinterlace, use the YADIF filter. Just add -filter:v yadif somewhere within the command line after the -i input.mp4 bit.
You don't need to extract the audio then re-mux. FFMPEG is willing to copy the source audio from the input stream to the output if you ask nicely by adding -acodec copy to your encoding command(s). Again, it needs to appear after the -i input.mp4 option, and maybe after the -f container option, too. I tend to place it after all the video options, just as a matter of personal style.
As far as replacing the input file, that should be clear: you encode to a temporary output file, then if that succeeds, your script says something like mv /tmp/whatever.mp4 input.mp4.


text:
She's the Investor Guru for On-line Creators
Cody Ko, a YouTube star with 5.7 million subscribers, found herself in a pickle in May. Two different startups wanted to give him shares, and he feared they were potentially competitive deals.
So Mr. Ko called for advice from someone he trusted: Li Jin.
Ms. Jin, a venture capitalist, suggested Mr. Ko, 30, speak honestly and openly to the founders of both startups about potential conflicts of interest. He agreed and ended up only pursuing one of the deals.
"I would never hesitate to contact her if I need anything," he said of Ms. Jin.
If there is such a thing as an it girl in venture capital these days, Ms. Jin, 31, would take that into account. She sits at the interface between startup investing and the rapidly growing ecosystem of online creators, both of which are brand new. And while she started her own venture firm, Atelier Ventures, just last year and raised a relatively small $ 13 million for a fund, Ms. Jin was one of the first Silicon Valley investors to take influencers seriously and write about creators she has supported years.
As a Harvard graduate who was inspired by the ideas of Friedrich Engels and Karl Marx, Ms. Jin is also aggressively pro-worker. She has made it clear in podcasts and her Substack newsletter that YouTubers should be given the same rights as other workers. One of the ideas she has championed is a "universal creative income" that would guarantee creators a basic amount to live on.
Now that big venture capital firms are flocking to influencer startups and launching Facebook, YouTube, and other $ 1 billion creator funds, Ms. Jin's track record has made her a go-to business guru for many digital stars made trying to find their way around the rapidly changing landscape.
Hank Green, 41, a top creator on YouTube and TikTok, said he often tossed ideas with her over the phone. Markian Benhamou, 23, a YouTuber with over 1.4 million subscribers, credits her with understanding what YouTubers are going through. Marina Mogilko, 31, a YouTube creator in Los Altos, Calif., Said Ms. Jin "started the entire creator economy movement in Silicon Valley."
"She talked about the creator economy for years and years before anyone else," said Jack Conte, co-founder and CEO of Patreon, a crowdfunding site for content creators. "She really sees the future before others do."
Ms. Jin, who has invested in Substack and Patreon, said that although her fund was small, she planned to put all of the money into companies that are transforming online work. "Everything I invest in is a creator-focused company," she said. "I think the impact I'm having is out of proportion to the dollar amounts."
Her credibility has been increased because she is also a creator. Ms. Jin is a frequent contributor to her Substack newsletter, leads an online course teaching founders how to invest in startups, and has created Side Hustle Stack, a free resource to help influencers find and rate platforms that they can use.
Beijing-born Ms. Jin immigrated with her family to the United States when she was 6, where her father received a PhD in economics from the University of Pittsburgh. Her early years in the country were meager, she said until her father dropped out of school and got a job. Her family eventually moved to Upper St. Clair, a town of about 20,000 people outside of Pittsburgh, where Ms. Jin attended a public school and enjoyed painting and writing.
At Harvard, she studied English and continued her creative activities. But at the urging of her family, who she said "wanted financial security for me," Ms. Jin switched to statistics major and did internships in banking and corporate marketing. After briefly working for Capital One after college, she moved to Silicon Valley at the age of 23 to work as a product manager at Shopkick, a purchase rewards app.
In 2016, Ms. Jin landed at the Silicon Valley venture company Andreessen Horowitz. At the time, the company was heavily focused on investing in marketplaces like Airbnb and Rappi, the Instacart of Latin America.
Ms. Jin was fascinated by how different marketplaces work and wrote a lot about them for the Andreessen Horowitz blog. She also started thinking about how different marketplace systems could evolve to help people build businesses on the internet.
This led Ms. Jin to advocate the influencer industry. It felt personal to watch YouTubers make a living online, she said, while also seeing great potential in working online and in the YouTubers as a business.
Your confirmation is meaningful, said influencers. "Your work at this big, traditional company and these things felt like someone was finally saying it," said Mr. Green, the YouTube star.
When the coronavirus pandemic struck last year and the world began to grow online, Ms. Jin saw an opportunity.
"I felt like Covid was going to speed up online-based work and people who want to become entrepreneurs," she said. "I realized that I had the opportunity to create an entirely new fund dedicated to this dissertation that would be at the forefront of advancing the nature of work and work on the Internet."
In May 2020 she left Andreessen Horowitz and founded Atelier Ventures. She has since invested in startups like PearPop, which influencers can use to capitalize on their social interactions, and Stir, which helps YouTubers manage their finances. She is one of the few investors who big influencers know by name.
"When you talk to someone who works in the creator economy, they all say, 'Oh, you need to talk to Li Jin,'" said a creator named Jasmine Rice, 23, a former OnlyFans influencer who runs a platform called. founded Fanhouse, which Ms. Jin invested in last year.
Ms. Jin has also publicly criticized the means YouTube, Facebook, TikTok and Snapchat offer influencers to create content for their platforms. She has pleaded with the tech industry to "stop" the funds from calling them "bread and games", arguing that the creators needed owners of the platforms that made money from them.
"Without ownership, creators ultimately enrich and empower * someone else * – platform owners – with their work," Ms. Jin tweeted in June.
Ms. Jin said the platforms need to be careful "not to restore a lot of the economic disparities that exist in the broader economy, rather than really empowering a new generation of online entrepreneurs." She calls a podcast moderated by her "Means of Creation", a piece about Marx's means of production.
Her views have made her a fascinating topic in the tech industry and left wing political space. The responses to her social media posts are full of memes suggesting that she is a socialist. Ms. Jin said she was most amused by the hustle and bustle.
"I'm very careful not to use this word, the S-word," she said of socialism. "It polarizes unnecessarily in the USA"
Ms. Jin said that she also believes in crypto networks because they are decentralized and "want to give control and ownership to their users". She has started investing in crypto-related platforms and recently supported Mirror, a decentralized publishing platform, and Yield Guild Games, which is building a gaming guild for the "metaverse" to help people in developing countries make money from video games. It has also partnered with creators to mint and sell works of art as NFTs or non-fungible tokens.
"My whole life has been bubbling with awareness," she said, "that the world is unjust and that we have to push it towards justice and fairness."
Since starting Atelier Ventures, Ms. Jin has moved out of Silicon Valley and managed her fund from her nursery in Pittsburgh. This summer she was nomadic and traveled the world surrounded by a changing cast of internet stars, artists, Gen Z tech founders and crypto pioneers.
In July, she hosted a jam-packed happy hour on a roof in New York City, attended by a who's who of internet culture and tech geeks, including the founders of the NFT platform OpenSea, product people from TikTok and Twitter, and other investors. From New York she flew to a crypto conference in Paris and hosted a "Creator Salon" in a café on the left bank.
She then flew to Greece at the invitation of Daniel Ek, the managing director of Spotify, and later attended a beach dinner organized by the Brilliant Minds Foundation with Emma Watson, Nicky Hilton and others.
Last month she went to Pittsburgh to regroup and reflect.
"It's just so unlikely that I'll be here," Ms. Jin said, "that I was born in Beijing and speak Chinese as my first and only language, and something brought me to the US and now I have the tools to do it to be able to "have a voice and influence."
Tags: Creators guru Investor Online Shes
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Men and women alike are affected by unwanted hair, which often appears on the face, upper lip, neck, chest, underarms, back, abdomen, bikini line and legs, although it may appear nearly anywhere on the skin.
If you are experiencing unwanted hair, please schedule a consultation with us to discuss your concerns. Our laser technicians will take the time to evaluate your areas of concern and determine the most effective treatment option for removing or reducing the appearance of unwanted hair through the most advanced, minimally invasive techniques.
Conditions such as polycystic ovary syndrome, Cushing's syndrome or certain medications can lead to a medical condition known as hirsutism, which involves an overproduction of male hormones in women. Hirsutism may also lead to acne, menstrual abnormalities, a deep voice and diabetes. It is often a chronic condition that leaves women with recurring unwanted hair throughout their lives unless a more permanent solution is sought.
Some people with normal hair growth may simply be bothered by the appearance of hair on their legs, underarms and bikini area, and seek treatment to achieve the smoother skin they desire. Regardless of the underlying factors, unwanted hair is a troubling aesthetic concern for many people.
There are many treatment options available for effective removal of unwanted hair, depending on the amount and location of the hair, as well as the patient's desired goals. Temporary treatments such as shaving and waxing are most commonly performed for their convenience and affordability, but require ongoing care to keep the skin smooth and free of hair. Many people frustrated with constantly treating areas of unwanted hair seek a more long-term solution from their doctor in order to achieve the appearance they desire.
Laser hair removal exposes specific areas of the body to beams of laser light that disable active hair follicles and delay or prevent re-growth. Ideal for patents with dark skin, this procedure effectively removes unwanted facial or body hair after a series of treatment sessions. Most patients experience a complete removal or significant reduction in hair growth after treatment and no longer have to worry about ongoing hair removal treatments.


text:
using UnityEngine;

public abstract class Subject : MonoBehaviour {

    public int Health;
    [HideInInspector]
    public ColliderType ColliderType;
    [HideInInspector]
    public delegate void dDie();
    [HideInInspector]
    public event dDie Died;
    protected SubjectType SubjectType;

    public void MakeDamage(int damage)
    {
        this.Health -= damage;
        if (this.Health <= 0)
            Die();
    }

    protected virtual void Die()
    {
        Died();
        Destroy(this.gameObject);
    }
}

public enum SubjectType
{
    None,
    Unit,
    Building
}

public enum ColliderType
{
    CapsulaCollider,
    BoxCollired
}

public enum UnitScriptType
{
    MeleeWarriorUnit
}

redpajama_set_name: RedPajamaGithub


With parts of Australia currently experiencing flooding, bushfires and other severe weather events, tax may be the last thing on your clients' minds. But it's reassuring to know that when your employer clients help their employees in an emergency situation, certain benefits provided are exempt from fringe benefits tax (FBT).
First aid or other emergency health care an employer provides their employee is also exempt if it is provided by an employee (or a related company employee), or is provided at your client's premises (or those of a related company), or at or near an employee's worksite.
For example the FBT exemption for first aid and other emergency health care applies to emergency treatment by a company doctor at the site of the emergency or accident, but won't apply if an employer pays for an employee's ongoing medical or hospital bills.
To discuss your own or your clients' circumstances, you can phone our natural disaster hotline on 1800 700 724.


A sample with lots of brilliant small crystals of Clinoclase, typical of the species. To add to this there are concretions of the rare arsenate Parnauite, which is a lighter green color. This comes from the David Lucas collection; number 575 and we will give the buyer David's label.
Radial and fan-like aggregates of very well defined Clinoclase crystals. They have very acute terminations, a very intense and uniform dark green color and are on a Quartz matrix, with Malachite that has an appreciably clearer green. We will send a copy of the analysis to the buyer. Very unusual, as are many of the samples from this collection.


text:
Q: Grails - Redirecting a Request Can't I just call then function "second" with no redirect action if I in the same class to get the same result i would get with redirect action in the following code?
  class SampleController {
      def first() {
        // redirect to the "second" action...
        redirect action: "second"
      }
      def second() {
        // ...
    } }

A:
Can't I just call then function "second" with no redirect action if I
  in the same class to get the same result i would get with redirect
  action in the following code?

Of course you can call a method from within a controller action but whether or not you get the same result depends on a number of factors.  The best way to approach this is to understand the differences between a redirect, a forward and invoking a method.  Understanding those will help you understand when each of them makes sense.
When you initiate a redirect the response is sent back to the client with information which causes the client to send a separate request back to your application.  A full HTTP round trip is made.  A forward is similar to a redirect except it all happens within the first request.  Control is sent to the forwarded action without needing to go back to the client and having it send a second request.  Invoking a method is different than all of that.  Invoking a method is just invoking a method and there are a number of things that won't happen when you do that.  For example, filters (Grails filters or regular servlet filters) will not be involved in that method call, even if the method you are calling is a controller action and there are filters configured that would normally apply to calls to that action.  You really should never invoke a controller action method directly.  If the method includes helper code that you might want to call, put that code in a regular non-action method (make it non-public) and then invoke it from wherever that makes sense.  Usually a better idea is to move that method out of the controller altogether and put it in a helper class where it will have a number of a benefits including that it can be re-used wherever appropriate, tested separate from a controller, etc.  This helper class might or might not be a Grails service, depending on how it is used and what it is doing.
I hope that helps.

A: You can use
forward action: "second"

Forwards a request without issuing an HTTP redirect.


The Apex K2 hip replacement has been linked to a risk of metal corrosion. It was pulled off the market in Australia after a study found that nearly 10% of patients needed revision surgery within three years.
The Schmidt Firm, PLLC is currently accepting Apex K2 induced injury cases in all 50 states. If you or somebody you know has been injured by a defective hip replacement, you should contact our lawyers immediately for a free case consultation. Please use the form below to contact our Defective Medical Device Litigation Group or call toll free 24 hours a day at (866) 920-0753.
What is the Apex K2?
OMNI Life Sciences, a Massachusetts-based medical device company, gained approval for the Apex K2 hip replacement in 2004. It is a modular implant with a metal femoral stem and interchangeable metal components in the femoral neck and head.
The Apex K2 was withdrawn from the Australian market in October 2012, shortly after it was linked to a 9.3% risk of failure within three years, and a 5.5% risk within one year. Conclusions were based on data from a national joint replacement registry since 2006.
The Apex K2 is not a traditional metal-on-metal hip replacement. However, it was linked to a risk of metal corrosion in a study published by the Journal of Arthroplasty October 2015.
After looking at 95 patients with the Apex K2, researchers found 10 had evidence of fretting or corrosion from the anti-rotation pin. They also observed a wide variety of complications, including ALVAL and two patients who needed revision surgery due to deep joint infections.
ALVAL is an acronym for "aseptic lymphocyte dominated vasculitis-associated lesions." It can occur as a result of metal particles accumulating around a hip implant and causing inflammation. Patients with this complication may experience chronic pain, inflammation, soft-tissue growths (pseudotumors), and more.
Hip implants are supposed to last at least 10-20 years, but an alarming number of metal-on-metal hips have been recalled because they can fail prematurely. Like most of these implants, the Apex K2 was approved by the FDA a 510(k) application. This type of approval lets manufacturers avoid rigorous safety studies so long as their device is "substantially equivalent" to another hip implant on the market.
The Schmidt Firm, PLLC is nationally recognized as a class action law firm, but our attorneys are not filing a class action lawsuit against Omni Life Sciences. Instead, we are filing individual lawsuits on behalf of people who were seriously injured or needed revision surgery after their Apex K2 hip implant failed prematurely.
Do I have an Apex K2 Lawsuit?


I told you in an earlier post that my family had had a hard end of 2015 and we did. As a result of that hubby purchased me a locket for Christmas to display both boys' photos in to keep close to my heart.
He originally got me a heart shaped locket that was pretty small in yellow gold and I don't wear anything but silver so I asked him if we could return it and get something bigger and in sterling silver. He was fine with that since I had to wear it not him. We picked a day, returned the original locket, and I picked out this rather large one instead.
With age I can't see the detail in little objects anymore and I liked the idea of an oval shape instead. I was thinking it would be easier to find a photo in the correct size.
I started looking through my photo library in Lightroom to find two photos I thought would work when I decided this was silly there has to be a way to get the photo size right the first time without printing several copies in an attempt to get it right.
What a brilliant idea right? I decided to try different printing methods to see what I liked the best. The ones on the left were printed on cardstock paper at home from a Canon printer. The ones in the middle I copied to a flash drive and had printed at our local grocery store on matte photo paper. And the ones on the right were printed at home on glitter paper from a Canon printer. I ended up going with the store prints on matte paper for my final project.
I also found a place called LOCKET PRINTS where you can upload your photos and they will mail you a full sheet of the same photo in several sizes made just for lockets. All you have to do is pick the size that fits your locket when it arrives.
I love my gift and wear it almost everyday. I have an upcoming fashion post where you can see how it hangs. I like a longer chain and this one hits just below the breast area.
I'm not sure if lockets are in fashion right now or if they ever go out of style but when I was out looking there seem to be several kinds on the market. I tend to lean more toward the vintage style ones for myself but there's so many out there to pick from. Right now would be a good time to ask for a locket if you're interested maybe your Valentine could get you one.
Thanks, Dawn! This is such a great post. Who new there was already something out there to perfectly size your photos. I could have also used this application when I was making cupcake toppers for a bridal shower with a picture of the engaged couple.
Carolyn that would have been a perfect way to use the program too.
What a great tool, thanks so much Dawn. My Great Grand Daughters and my Daughter will be so pleased today when I present these in their new lockets.
You're welcome Melissa it was so easy once I found the perfect program.
Thanks for the tip. I have a heart pin/ locket that's about 2 inches at its widest part. I am going to try out this site and print a pic to go inside.
Carol I can't wait to see how yours turns out. That is the reason I took the heart shaped one back, I thought it would be hard to find a photo that fit but not with this program.
What a great resource, thanks for sharing. There is so many applications for this program, I am going to bookmark it for sure! I love lockets.
Pam yes once you measure and find your correct locket size it goes fast for making the photos.
Thanks, Dawn, I had no idea there was something like this. I have two different lockets that I wear. One was given to me by my parents when I was a teenager. Sadly, they are empty bc I never knew how to get a picture to fit nicely in them. I definitely want to try this.
Oh Becky I'm so excited for you to try it. It's very user friendly and you will be so happy with the results.
Thanks so much for sharing this with us Dawn…and the boys are very handsome!
Thank you Shirley it was nice to get similar photos of them for my locket.
Thanks for the locket info! Your guys are handsome and now you can literally hold them in your heart. How thoughtful of a gift from your hubby!
Susan thank you for stopping in today. I'm loving my new locket and wear it most days.
I uploaded my photo, but it was so tiny on the page I couldn't even see it. Do you know why this is?
It should be tiny, but it should also print out the same size as your locket. Did you pick your locket size from the choices?
I have a six circular style sterling silver ball locket. The size of the photo plate is approx 0.7. Can you assist me with shrinking pictures that small?
Rhonda the link I provided should have an option for that size and it shrinks it automatically for you.
That Locket Studio site is THE BOMB!!! That was super useful!! And, as you mentioned, F*R*E*E!!!!! (and easy). Thanks for the excellent recommendation!! I just used it for a gift, but now I want to run out and buy a locket for myself!
Hello I'm trying to figure out to get two locket pictures made.
Amber 4X6 isn't square so you'd need to make it a 4X4 or 6X6. Most of the square prints are called insta prints if that helps.
Thank you, post was so helpful!
Could you tell me how you were able to cut it so precisely? I tried and I basically cut like a 3 year old. ?
Thank you for your post. It was helpful to know how to size the pictures and the Locket Studio website was fantastic.
Thank you for this post. I'll try your suggestions. We've also had a horrible time the last 2 years, and I'm looking for the perfect locket for myself for much the same reason. I hope yours brings you peace.


text:
Recent Advances and Prospects in Design of Hydrogen Permeation Barrier Materials for Energy Applications—A Review
Autotoxicity of Endogenous Organic Acid Stress in Two Ganoderma lucidum Cultivars
Catalytic Deoxygenation of Hydrolyzed Oil of Chlorella Vulgaris Microalgae over Lanthanum-Embedded HZSM-5 Zeolite Catalyst to Produce Bio-Fuels
Previous Article in Special Issue
Dissipation and Residue of Metalaxyl-M and Azoxystrobin in Scallions and Cumulative Risk Assessment of Dietary Exposure to Hepatotoxicity
Academic Editors
Xingang Liu
Zhiming Xiao
Li, R.
Zhang, Y.
Li, Y.
Wang, Z.
Wang, M.
An Innovative Chiral UPLC-MS/MS Method for Enantioselective Determination and Dissipation in Soil of Fenpropidin Enantiomers
Yanqing Zhang
Yanhong Li
Zihao Chen
Zhen Wang
Minghua Wang
Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing 210095, China
Author to whom correspondence should be addressed.
Molecules 2022, 27(19), 6530; https://doi.org/10.3390/molecules27196530
Received: 15 September 2022 / Revised: 28 September 2022 / Accepted: 29 September 2022 / Published: 2 October 2022
(This article belongs to the Special Issue Application of LC-MS/MS in Biochemistry II)
As a chiral piperidine fungicide, fenpropidin has been widely used to control plant diseases. However, there are rare studies that have investigated fenpropidin at the enantiomer level. In this study, the single-factor analysis combined with a Box-Behnken design was used to obtain the optimal enantio-separation parameters of the fenpropidin enantiomers on ultra-performance liquid chromatography-tandem mass spectrometry. The absolute configuration of two fenpropidin enantiomers was confirmed for the first time using electron circular dichroism and optical activity. On the Lux cellulose-3 column, S-(-)-fenpropidin flowed out before R-(+)-fenpropidin. The enantio-separation mechanism was revealed by molecular docking. A modified QuEChERS method was developed for the trace determination of the fenpropidin enantiomers in seven food and environmental substrates. The average recoveries were 71.5–106.1% with the intra-day and inter-day relative standard deviations of 0.3–8.9% and 0.5–8.0%. The method was successfully verified by enantioselective dissipation of fenpropidin in soil under the field. R-(+)-fenpropidin dissipated faster than S-(-)-fenpropidin, and the half-lives were 19.8 d and 22.4 d. This study established a brand-new effective chiral analysis method for the fenpropidin enantiomers, providing a basis for accurate residue monitoring and the risk assessment of fenpropidin.
fenpropidin; enantio-separation; absolute configuration; Box-Behnken design; enantioselective dissipation; molecular docking
Pesticides play an important role in controlling pests, diseases and weeds, protecting crops and regulating growth. It is worth noting that the number of chiral pesticides is relatively large, accounting for 30% of all pesticides sold worldwide, and it is increasing gradually with the introduction of complex structures [1,2]. The chiral pesticides usually contain more than two enantiomers. The enantiomers of each chiral pesticide usually have the same physical and chemical properties; however, they have different recognition sites for organisms, which may exhibit different biological activity, non-target toxicity and environmental behavior [3,4,5,6]. Therefore, studies on the racemic levels of chiral pesticides may obtain inaccurate data. Enantioselectivity of chiral pesticides has received considerable attention worldwide. For instance, Li et al. found that the fungicidal activity of S-(+)-fluxametamide is up to 52.1–304.4-fold higher than R-(-)-fluxametamide [7]. Li reported imazamox has enantioselective toxicity to Lemna minor, R-imazamox was about six times more toxic to Lemna minor than S-imazamox [8]. Wang found that pydiflumetofen had enantioselective degradation in soil, R-(+)-enantiomer degraded faster than S-(-)-enantiomer [9]. In order to improve the efficiency and reduce the use of chiral pesticides, further avoid the threat of inefficient and highly toxic enantiomers to the environment and non-target organisms, some countries, such as the Netherlands and Switzerland, have registered single isomers [10]. Therefore, enantioselective studies on chiral pesticides can obtain more scientific, reasonable and accurate data for a comprehensive risk assessment of chiral pesticides.
Fenpropidin, 1-[(RS)-3-(4-tert-butylphenyl)-2-methylpropyl] piperidine, is a typical chiral pesticide developed by Syngenta Co., Ltd. and belongs to the new piperidine fungicides which contain a chiral center and two enantiomers. Fenpropidin eventually inhibits sterol synthesis by inhibiting Δ14-reductase and Δ8 → Δ7-isomerase [11,12]. Maximum residue limits (MRLs) for fenpropidin have been established in many countries. The MRLs of fenpropidin in wheat were 1 mg/kg in China, 10 mg/kg in bananas in America and Canada and in the European Union, the MRLs were 0.01 to 0.6 mg/kg in different foods. However, most studies of fenpropidin were still carried out at the racemic level. For example, LC-MS/MS and GC-MS were used by Zhao et al. to study the dissipation of fenpropidin in wheat and soil and found that the half-life was between 3.1 to 3.3 days in wheat plants and 13.4 to 16.5 days in soil [13]. Unfortunately, fenpropidin has been found in environmental substrates. Hvězdova et al. tested different types of pesticides in a variety of soils and found that 20% of soils contained fenpropidin and 13% contained fenpropidin at levels greater than 0.01 mg/kg [14]. Schafer detected fenpropidin in 16 small streams, and its concentration was as high as 1 mg/kg [15]. Residual fenpropidin may pose a threat to environmental safety and human health; thus, accurate monitoring of fenpropidin in agricultural products and environmental samples to ensure food and environmental safety is necessary. However, as far as we know, there are few reports on the analysis of fenpropidin from the enantiomer level. Only Buerge et al. reported the stereoselective metabolism of fenpropidin in beet and wheat by GC-MS/MS [16]. Therefore, establishment of a rapid, sensitive and accurate chiral analysis method for the detection of the fenpropidin enantiomers in food and environmental samples is an urgent task.
Herein, a novel, sensitive and efficient chiral analysis method for the determination of fenpropidin enantiomers in bananas, grapes, apples, wheat, soybeans, rice and soil was established by ultra-performance liquid chromatography-tandem triple quadrupole mass spectrometry (UPLC-MS/MS). A novel Box-Behnken design (BBD) experiment was performed to comprehensively and systematically evaluate the influence of chiral separation parameters (chiral stationary phases (CSPs), mobile phase composition and proportion, temperature, flow rate) for the separation on the basis of single factor optimization test. The absolute configuration of the fenpropidin enantiomers was confirmed by electron circular dichroism (ECD) and polarimetry. Furthermore, the chiral recognition mechanism of the fenpropidin enantiomers was studied by molecular docking under ideal conditions. The established method was successfully performed on the enantioselective dissipation of the fenpropidin enantiomers in soil. Simultaneously, the stability of the fenpropidin enantiomers in different solvents and water was studied. These results will provide more accurate and reliable data for environmental monitoring and risk assessment of fenpropidin.
2.1. Enantio-separation and Optimization
2.1.1. Optimization of Chiral Stationary Phases
CSP is the dominant factor in chiral recognition [17,18]. The polysaccharide-based chiral column is one of the most widely used chiral columns [19,20]. Thus, the enantio-separation effect of fenpropidin on three different cellulose-derived CSPs (Lux cellulose-1 (L1), Lux cellulose-2 (L2) and Lux cellulose-3 (L3)) was studied. We have studied the enantio-separation of fenpropidin on different chiral columns under various mobile phases such as formic acid water/acetonitrile (methanol), ammonia solution/acetonitrile (methanol), ammonium acetate/acetonitrile (methanol) and ammonium formate/acetonitrile (methanol). Fenpropidin enantiomers on the chiral column L1 and L2 failed to achieve complete baseline separation. But complete baseline separation of the fenpropidin enantiomers was obtained on the L3 (Figure 1a). Therefore, L3 was selected as the stationary phase in this study to separate the fenpropidin enantiomers.
2.1.2. Optimization of Mobile Phase
The retention time (Rt), elution and separation of chiral compounds are affected by the mobile phase [21]. The common organic phases (methanol and acetonitrile) combined with several aqueous phases (formic acid water, ammonia solution, ammonium acetate and ammonium formate) were used to study the enantio-separation effect of fenpropidin. Acetonitrile as the organic phase coupled with different aqueous phases could not achieve enantio-separation, while methanol can achieve a good separation effect. Typical chromatograms were shown in Figure 1b.
What is more, methanol combined with formic acid, ammonium acetate, and ammonium formate could not achieve the baseline separation. Only a methanol/ammonia solution could achieve the enantio-separation of fenpropidin (Figure 1c). That is probably because an appropriate buffer solution can significantly change the ionization effect, adjust the pH and improve the peak shape and signal response [22]. Fenpropidin is alkaline, and ammonia solution can promote its ionization. Therefore, the ammonia solution was the best buffer for the enantio-separation of fenpropidin. In addition, the influence of 0.05%, 0.1% and 0.2% ammonia solution on the mobile phase was compared (Figure 1d). All of them could successfully separate the fenpropidin enantiomers with the resolution (Rs) of 1.80, 1.96 and 2.27, respectively. When the mobile phase was 0.1% ammonia solution, the maximum response value was obtained (Table S1). Considering the Rs, response value and the degree of acid and alkali tolerance of a chiral column, 0.1% ammonia solution was selected as the mobile phase.
2.1.3. Effects of the Column Temperature on Enantio-Separation
The adsorption and desorption rates of target compounds in stationary phases usually were affected by temperature, thus, affecting the separation effect [23]. The van't Hoff equations got good linear relationships (R2 > 0.9941) at the column temperature between 20–40 °C. The supplementary material Table S2 showed the detailed thermodynamic parameters. The Rs of the enantiomers gradually decreased when the temperature increased (Table S3). In addition, the ∆∆H0 and ∆∆S0 were −2.97 kJ/mol and −6.38 J/(mol·k) which indicated enthalpy drove the separation of the fenpropidin enantiomers.
2.2. Box-Benhnken Design
The interaction of many factors affects the enantio-separation of chiral compounds. Considering from the single factor level is not comprehensive enough, BBD can predict the main influence variables and the interaction of multiple variables [24]. It is usually used to evaluate the nonlinearity relationship of three to seven input variables and output variables. To further study the influence of Rt (Y1) and Rs (Y2) of the fenpropidin enantiomers by flow rate (X1), the percentage of methanol (X2), and temperature (X3), a BBD was used in this study. In each of these experiments, two dependent variables changed and the other one remained at the medium level. The accuracy and precision of the BBD were proven through the dependent variable experiment at the center point with five repetitions. Two second-order models (Equations (1) and (2)) eliminating insignificant factors were obtained by the Design Expert 8.0.6 trial software.
Y 1 = 16 . 69 − 2 . 61 X 1 + 12 . 16 X 2 − 1 . 30 X 3 + 0 . 1150 X 1 X 3 + 0 . 7714 X 1 2 + 0 . 3114 X 3 2
Y 2 = 2.24 − 0.0977 X 1 + 0.9115 X 2 + 0.0015 X 3 − 0.0879 X 3 2
The rationality of the fitted models (Y1 and Y2) was evaluated by the ANOVA of Rt and Rs (Tables S4 and S5). In this study, a good linearity was obtained with R2 = 0.9581 and R2 = 0.9625 for Y1 and Y2. The two fitted models were significant differences (p < 0.0001). The significant factor affecting Rt was methanol percentage (X2) (p < 0.0001). The percentage of methanol (X2) affected the Rs (p < 0.0001).
As shown in Figure 2, the interaction of multiple factors in the chiral separation process was illustrated by the three-dimensional (3D) response surface plots and two-dimensional (2D) contour plots. The optimum conditions were obtained through 17 BBD experiments with the flow rate of 0.8 mL/min, percentage of methanol of 88.3%, and temperature of 32.7 °C. The predicted results by the BBD were in perfect agreement with the actual results on UPLC-MS/MS, with the Rt of the first enantiomer being 11.00 min and the Rs being 1.96.
2.3. Absolute Configuration
The specific optical rotations of peak 1 and peak 2 were calculated as [α] = −9.57° and [α] = +9.89° (methanol, c = 0.01). The calculated ECD spectrum was acquired by using the lowest energy conformation of each fenpropidin enantiomer (Figure 3). It was found that the calculated and experimental ECD spectra were consistent, and there was a mirror symmetry phenomenon. Thus, peak 1 was S-(-)-fenpropidin and peak 2 was R-(+)-fenpropidin (Figure 4).
2.4. Molecule Docking
The binding modes and interaction between the fenpropidin enantiomers and CSPs were investigated by molecular docking to reveal the enantio-separation mechanism of the fenpropidin enantiomers.
The enantio-separation of fenpropidin was carried out based on CSPs. Only the L3 achieved the baseline separation of the fenpropidin enantiomers, while the L1 and L2 did not achieve the baseline separation at all. Therefore, the possible interaction between chiral compounds and CSPs can be explored by molecular docking. And the binding modes of the fenpropidin enantiomers and the L3 were presented in Figure 5a,b. The active pocket consisted of several glucose derivatives, and the fenpropidin enantiomers interacted with the L3 including the π-cation interaction and hydrogen-bond interaction. As shown in the Figure 5a,b, although two enantiomers had the same type of interaction with the L3, the distance of the hydrogen bond and π-cation between two enantiomers and the binding site was different due to the different stereostructure of the fenpropidin enantiomers. The heterocyclic N atom in two fenpropidin enantiomers formed hydrogen bonds with the O-H group bonds on the L3 branch, and combined with the aromatic ring to form π-cation interaction. The distances between the two atoms of the hydrogen bond formed by R-enantiomer and S-enantiomer with the binding site of the L3 were 2.17 Å and 2.39 Å, respectively. In addition, fenpropidin had π-cation interaction with two π systems in the active center pocket. The difference in spatial structure between R-fenpropidin and S-fenpropidin led to the different distances of the π system and the cations on the ligand. Compared with some classical interactions (such as hydrogen-bond, electrostatic and hydrophobic interactions), π-cation interaction was considered to be a new type of intermolecular interaction. Such interaction had characteristic requirements for the binding geometry [25]. The strength of the π-cation interaction is comparable to hydrogen bonds. As shown in Figure 5a,b, the distances of π-interaction between the R-enantiomer and the L3 were 4.36 Å and 5.32 Å, and the distances between S-enantiomer and the L3 were 4.26 Å and 6.22 Å. The geometry of one π-cation force in S-enantiomer was greater than 6 Å. Therefore, although the fenpropidin enantiomers have the same interaction force as the L3, the distances between two enantiomers and the L3 were different due to the different spatial structures. As shown in the Table S6, the results of free-binding energy were consistent with the separation results of the fenpropidin enantiomers on the L3. The binding energies between S-enantiomer and R-enantiomer were significantly different. The analysis based on the binding energy and intermolecular interaction showed that the binding ability of S-fenpropidin to the L3 was weaker than that of R-fenpropidin, so S-fenpropidin flowed out before R-fenpropidin on the L3 column. The molecular docking results can clearly explain the mechanism of enantio-separation of fenpropidin. It is clear that the mechanism of fenpropidin enantio-separation on the L3 may be due to the difference in the distances of the hydrogen bond and π-cation interaction between the fenpropidin enantiomers and the L3.
As shown in Figure S1a,b, R-enantiomer and S-enantiomer formed π-cation interactions and hydrogen bonds with the L1, respectively. R-enantiomer and the L2 formed hydrogen bonds, and S-enantiomer formed π-cation interactions as shown in Figure S1c,d. Based on the previous results, fenpropidin enantiomers had similar intermolecular forces with the L1 and L2, and their free-binding energies were not significantly different. Therefore, we speculated that only containing hydrogen bonds or π-cation interactions was not enough to achieve enantio-separation. The difference in the free-binding energy between CSPs and two enantiomers also showed that there had no significant difference on the L1 and L2 (Table S6). Therefore, the enantio-separation of fenpropidin was only achieved on the L3. The results of molecular docking strongly confirmed the results of the optimization experiment of enantio-separation and explained the mechanism of fenpropidin enantio-separation.
2.5. Method Validation
2.5.1. Specificity, Linearity, LOQs and Matrix Effect
This method was highly specific, and there was no interfering substance in the presence of the fenpropidin enantiomers during Rt in all blank samples.
An excellent linearity of the fenpropidin enantiomers in solvent and seven matrix-matched calibration curves was obtained with R2 ≥ 0.9988 under the concentration of 5–500 μg/kg (Table 1). The limit of quantifications (LOQs) of the fenpropidin enantiomers were 5 μg/kg.
The fenpropidin enantiomers showed no matrix effect (ME) in wheat, apples, soybeans and soil, but moderate ME with signal suppression in grapes and bananas. There was no ME in rice with S-(-)-fenpropidin, but there was a matrix suppression effect in rice with R-(+)-fenpropidin. ME may be due to coextract which may significantly interfere with the analysis process of target compounds and affect the accuracy of analysis results [26,27]. Therefore, the standard calibration curve of matrix matching was used for accurate quantification
2.5.2. Accuracy and Precision
The mean recoveries of the fenpropidin enantiomers in seven matrixes were 71.5–106.1%, the intraday and intraday relative standard deviations (RSDs) were 0.3–8.9% and 0.5–8.0% (Table 2). The data showed that the enantioselective detection method of the fenpropidin enantiomers in wheat, apples, soybeans, grapes, bananas, rice and soil had good accuracy and precision.
2.6. Stability of Fenpropidin Enantiomers
It has been proved that the configuration of chiral pesticide enantiomers is unstable under experimental conditions and is prone to configuration transformation [28,29]. The stability of the fenpropidin enantiomers dissolved in different solvents was verified. And the results showed that there was no configuration transformation that occurred in the fenpropidin enantiomers.
2.7. Enantioselective Dissipation of Fenpropidin in Soil
The kinetic equations for the dissipation of S-(-)-fenpropidin and R-(+)-fenpropidin in soil were C = 0.7882e−0.031t (R2 = 0.8728) and C = 0.8624e−0.035t (R2 = 0.9121), which well fitted the first order kinetic equation. The half-lives of R-(+)-fenpropidin and S-(-)-fenpropidin in soil were 19.8 d and 22.4 d, the dissipation of the fenpropidin enantiomers in soil was enantioselective (p < 0.05) (Table S7), and R-(+)-fenpropidin dissipated faster than S-(-)-fenpropidin (Figure S2a). EF at 2 h and 35 d were 0.48 and 0.52 (Figure S2b). This method can be helpful to improve the accuracy of the risk assessment of fenpropidin.
3. Materials and method
3.1. Reagents and Materials
The fenpropidin (≥95%) was obtained from Dr. Ehrenstorfer (Augsburg, Germany). Two fenpropidin enantiomers (≥98% purity) were acquired from Chiralway Biotech Co., Ltd. (Shanghai, China). HPLC-grade ammonia solution was obtained from Shanghai Aladdin Biotech Co., Ltd. (Shanghai, China). HPLC-grade methanol and acetonitrile were bought from Germany Merck KGaA (Darmstadt, Germany). Ultra-pure water was purchased from China Resources C'estbon Beverage (China) Co. Ltd. (Shenzhen, China). Primary secondary amine (PSA, 40–63 μm) was purchased from ANPEL Laboratory Technologies, Inc. (Shanghai, China). Racemic fenpropidin and its two enantiomers were dissolved in HPLC-grade methanol to prepare stock standard solutions and all of them were placed in the dark at −20 °C.
3.2. Instrumental Analysis
A Waters ACQUITY UHPLC system tandem triple quadrupole mass spectrometer (Waters Corp., Milford, MA, USA) was used for the enantio-separation and analysis of fenpropidin in a positive electrospray ionization source (ESI+). The L3 chiral column (250 × 4.6 mm inner diameter, 5 μm, Phenomenex, Torrance, CA, USA) was selected for separating the fenpropidin enantiomers. The flow rate and volume ratio of the mobile phase (methanol and 0.1% ammonia solution) were 0.8 mL/min and 88.3:11.7. And the column temperature was 32.7 °C. Multiple-reaction monitoring mode was used to perform MS analysis. The mass conditions were set as follows: 1.25 kV capillary voltage, 500 °C desolvation temperature, 150 °C source temperature. A 50 L/h cone gas flow (99.95% nitrogen) and 1000 L/h desolvation gas flow (99.95% nitrogen) were used. The collision gas was 99.99% argon at a pressure of 2 × 10−3 mbar in the T-wave cell. The quantitative and qualitative determination of the fenpropidin enantiomers were through the characteristic product ions emerging from hydrogen adduct [M+H]+ (m/z 274 > 147) and (m/z 274 > 132) under the cone voltage and the collision energy of 26 and 40 V. The data was collected and analyzed by Masslynx NT version 4.2 (Waters, Milford, MA, USA).
3.3. Separation Condition Optimization
In the case of comprehensively and systematically assessing the effect of separation parameters on the enantio-separation of the fenpropidin enantiomers, the influence of various chiral columns and mobile phase composition was preliminarily assessed through the single factor analysis. A novel BBD experiment was applied to study the influence of multiple factors (column temperature, flow rate, mobile phase ratio) on enantio-separation from three levels (high, medium and low) with a total of 17 experiments by the Design Expert 8.0.6 trial software, and, finally, the optimal separation conditions were obtained. Specific conditions are as follows: the column temperature was between 25 and 35 °C, the methanol ratio was 80% to 95% and the flow rate was 0.6 mL/min to 0.8 mL/min. Response variables were set as the Rt of Peak 1 and the Rs between Peak 1 and Peak 2. The quadratic model was utilized to calculate the response surface as shown in Equation (3) [30]:
Y = b 0 + b 1 X 1 + b 2 X 2 + b 3 X 3 + b 11 X 1 2 + b 22 X 2 2 + b 33 X 3 2 + b 12 X 1 X 2 + b 13 X 1 X 3 + b 23 X 2 X 3
where Y is the predicted response, bn are quadratic coefficients, X1, X2, and X3 is the flow rate, the percentage of methanol, and the column temperature respectively.
The effect of different optimization conditions on the separation was evaluated by the capacity factor (k), separation factor (α) and Rs using Equations (4), (5) and (6). The van't Hoff equations were used to calculate the thermodynamic parameters as shown in Equations (5) and (6) [31].
k = ( t R − t 0 ) / t 0
α = k 2 / k 1
R s = 2 ( t 2 − t 1 ) / ( w 1 + w 2 )
ln k = − Δ H 0 / R T + Δ Δ S 0 / R + ln Φ
ln α = − Δ Δ H 0 / R T + Δ Δ S 0 / R
where tR, t0 and w is the Rt, the void time, the peak width, respectively; R, T and Φ is the gas constant, the absolute temperature and the ratio of the solid phase and the mobile phase, respectively. ΔΔH0 and ΔΔS0 are the enthalpy and entropy variations.
3.4. Determination of Specific Optical Rotation
A SGW-1 polarimeter (Shanghai INESA Physico-Optical Instrument Co., Ltd., Shanghai, China) was utilized to determine the optical activity of each fenpropidin enantiomer (acetonitrile, 0.01 g/mL) at 589.4 nm, repeat three times. Using Equation (9) to calculate the specific rotation.
[ α ] = α / ( c × L )
where [α], α, C and L represent specific rotation, optical rotation, the concentration of the fenpropidin enantiomers (g/mL) and the width of the quartz tube (dm).
3.5. Confirmation of Absolute Configuration
In stereochemical analysis, ECD is generally considered to be one of the most effective techniques for confirming the absolute configuration of chiral compounds [32]. The experimental ECD spectra of the standard solution of two fenpropidin enantiomers (acetonitrile, 10−5 mol/mL) were conducted by the J815 circular dichroism spectropolarimeter (Jasco, Tokyo, Japan) at 25 °C. The standard solution should be placed in a 0.1 cm quartz cell. The measurement was carried out at the scanning wavelength of 200–400 nm and a scan speed of 50 nm/min. The experimental ECD spectra were drawn by Origin software (version 8.61).
At present, the method of quantum chemical calculations was usually used to confirm the absolute configurations of chiral compounds [33]. Gaussian 09 W software was used to acquire the calculated ECD spectra of the fenpropidin enantiomers. Firstly, the molecular mechanics field (MMFF94) was used to optimize the 3D structures of R-fenpropidin and S-fenpropidin. The geometric optimization and frequency calculation were conducted to get the most stable configuration of two enantiomers based on the B3LYP function of the 6-311+G (2d, p) basis set. The absolute configurations of the fenpropidin enantiomers were confirmed based on the similarity between the calculated ECD and the experimental ECD spectra.
3.6. Chiral Stationary Phase Recognition Mechanism
A computer simulation was implemented to explore the enantio-separation mechanism between two enantiomers and different CSPs. The 3D structures of the chiral stationary phases (L1, L2, L3) were derived based on Yamamoto's research [34]. The process was performed using Schrodinger Maestro Suite 2020 which was professional computational chemistry and molecular modeling tool. LigPrep was used to desalt and then generate all possible conformations at pH 7.0 using Epik, and retain the specified chiralities. Finally, the OPLS_2005 force field was selected to minimize different compounds. Protein Preparation Wizard was used to optimize receptors. Glide scoring was used to assess the affinity between the CSPs and fenpropidin enantiomers.
3.7. Sample Preparation
Soil samples were gathered from a cropland in Nanjing in 0–15 cm depth, mixed, air-dried and, finally, sifted the soil with a 2 mm screen. Bananas, grapes, apples, wheat, soybeans and rice were all bought from local supermarkets in Nanjing. There was no substance in the Rt of fenpropidin. All samples were homogenized and stored at −20 °C. Fenpropidin was not found in any of the matrices.
Matrix samples were extracted according to the improved QuEChERS. Each sample was weighed 5 g using an electronic balance and then transferred into a 50 mL polytetra-fluoroethylene centrifuge tube. After wetting the soil with 5 mL ultrapure water, 10 mL acetonitrile was added. Other matrices only contained 10 mL acetonitrile. Then, the mixture was vortexed for 5 min at 2500 rpm, and fully extracted by ultrasound for 13 min. After completing the above steps, 3 g NaCl was added to the centrifuge tube followed by vortexing for 2 min, and then centrifugation at 4000 rpm for 5 min. After centrifugation, 1.5 mL of the organic phase was shifted to a centrifuge tube containing 50 mg PSA for purification. Then, it was violently shaken for 1 min and centrifuged at 8000 rpm for 5 min. The supernatant was filtered by a 0.22 μm nylon syringe filter; then, using UPLC-MS/MS, the samples were analyzed.
The specificity, ME, linearity, LOQ, accuracy and precision of the method were assessed based on the SANTE/12682/2019.
The blank samples were determined to observe whether there were interfering compounds near the Rt of the fenpropidin enantiomers. The solvent standard curve and matrix matching calibration curve were carried out to calculate the linearity and ME. The ME was evaluated by Equation (10). The LOQ was taken for the lowest validated spike level that met the requirement of the average recovery (70–120%) and RSDs ≤ 20% in each matrix. The repeatability and reproducibility were assessed on the same day and three nonconsecutive days through five replicates of six spiked samples (apples, grapes, bananas, soybean, wheat and rice) at three different levels (5–500 μg/kg) and soil at four different levels (5–1000 μg/kg). The average recoveries and the RSDs were calculated to analyze the accuracy and precision.
M E = ( t h e s l o p e o f m a t r i x m a t c h e d c u r v e − t h e s l o p e o f s o l v e n t c u r v e ) / t h e s l o p e o f s o l v e n t c u r v e × 100 %
the |ME| values between 20% and 50% have moderate ME, more than 50% are considered as strong ME, less than 20% shows no ME.
3.9. Stability of Fenpropidin Enatiomers
The fenpropidin enantiomers were dissolved in the solvents (acetonitrile, methanol and water) with a concentration of 0.5 mg/kg and kept at 4 °C and 25 °C. Then the concentrations of fenpropidin enantiomers at 0, 1, 3, 7, 14, 30, 60, 120 and 180 days were detected by UPLC-MS/MS under the optimal separation conditions to study the stability.
3.10. Enantioselective Dissipation in Soil
Soil dissipation experiments were carried out in Nanjing, China, and the soil without fenpropidin was selected as the test field. Three treatment plots and one control plot with 10 m2 of each plot were set, and each test plot was isolated by a 1 m wide isolation belt. A 10% fenpropidin emulsion solution was sprayed in the treatment plot at 1000 g (a.i.)/ha. Soil samples were collected at 2 h, 1, 3, 5, 14, 21, 28 and 35 d, and the samples were evenly mixed before being stored at −20 °C.
Enantio-selective dissipation of the fenpropidin enantiomers in soil was assessed by the first-order kinetic equation (Equation (11)), the half-life (t1/2) and enantiomer fraction (EF) were obtained by Equations (12) and (13).
C t = C 0 e − k t
t 1 / 2 = ln 2 / k = 0.693 / k
E F = C S / ( C S + C R )
where C0 and Ct are the concentration at time 0 and t; k stands for the dissipation rate constant. CS and CR are the concentration of the S- and R-fenpropidin, respectively.
In this study, a fast and trace chiral analytical method for the enantioselective determination of the fenpropidin enantiomers in food and environmental samples using UPLC-MS/MS combined with the Lux cellulose-3 was established. The best enantio-separation conditions of the fenpropidin enantiomers were acquired by the single factor analysis combined with a surface response method. The absolute configuration of two fenpropidin enantiomers was confirmed by specific rotation and calculated and experimental ECD spectra. The elution order was S-(-)-fenpropidin and R-(+)-fenpropidin on the Lux Cellulose-3. The molecular docking results revealed the enantio-separation mechanism of the fenpropidin enantiomers. The excellent linearity, accuracy and precision acquired in the seven food and environmental matrix showed that the method was reliable. R-(+)-fenpropidin dissipated faster than S-(-)-fenpropidin. The establishment of the chiral analysis method breaks the limitation of traditional analysis of fenpropidin at the racemic level, which can more accurately monitor the residual of the fenpropidin enantiomers in the environment and food, and provide a basis for environmental risk assessment.
The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/molecules27196530/s1, Table S1: Effect of different proportion of buffer solution on the enantioselective separation of fenpropidin. Table S2: Van't Hoff equations and thermodynamic parameters. Table S3: Influence of temperature on the enantio-separation of fenpropidin on Lux cellulose-3. Table S4: ANOVA of retention time (Y1) and independent variables (X1, X2 and X3). Tabe S5: ANOVA of resolution (Y2) and independent variables (X1, X2 and X3). Table S6: Free binding energy of fenpropidin enantiomers to CSPs. Table S7: The half-lives of fenpropidin enantiomers in soil. Figure S1: The docking posture of R-fenpropidin (a,c) and the posture of S-fenpropidin (b,d) with L1, L2. Figure S2: The dissipation trends (a) and EFs (b) of the fenpropidin in soil.
Conceptualization, R.L. and M.W.; Data curation, Y.L., Z.C. and Z.W.; Formal analysis, R.L., Y.Z., Z.C., Z.W. and M.W.; Funding acquisition, M.W.; Investigation, R.L., Y.Z. and Z.C.; Methodology, R.L.; Project administration, M.W.; Resources, R.L. and M.W.; Software, M.W.; Supervision, M.W.; Validation, Y.Z., Y.L. and M.W.; Writing—original draft, R.L., Y.L. and Z.W.; Writing—review and editing, R.L. and M.W. All authors have read and agreed to the published version of the manuscript.
This study was supported by the National Key Research and Development Program of China (2016YFD0200207).
Supplementary Materials File is available.
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Figure 1. Chromatograms under different stationary phases (a), organic phases (b), aqueous phases (c), ammonia solution proportion (d) and temperature (e).
Figure 2. Two-dimensional contour plot (a,c) and three-dimensional response surface plot (b,d) for the influence of the flow rate, temperature and mobile phase ratio on Rt and Rs.
Figure 3. Experimental (a) and calculated ECD spectrum (b) of fenpropidin enantiomers.
Figure 4. The chemical structures and typical chromatograms of the fenpropidin enantiomers.
Figure 5. The docking posture of R-fenpropidin (a) and S-fenpropidin (b) with L3.
Table 1. Linear regression equation, matrix effect and LOQs for the fenpropidin enantiomers in different matrices.
Matrix Effect (%)
(μg/kg)
S-(-)-fenpropidin acetonitrile y = 10537x − 32578 0.9998
wheat y = 10501x + 43144 0.9991 −0.26 5
grape y = 8249.5x + 19379 0.9999 −21.71 5
apple y = 9070.7x − 16612 1.s0000 −13.92 5
banana y = 7968x − 6797.5 1.0000 −24.38 5
soybean y = 10552x + 30602 0.9995 0.14 5
rice y = 8508.9x + 16128 0.9997 −19.25 5
soil y = 10666x + 43568 0.9989 1.22 5
R-(+)-fenpropidin acetonitrile y = 11301x − 59712 0.9995
wheat y = 9972.5x + 68949 0.9988 −11.76 5
grape y = 8346.9x + 9890.1 1.0000 −26.14 5
apple y = 9404.4x − 24369 0.9999 −16.78 5
banana y = 8559.4x − 16592 1.0000 −24.26 5
soybean y = 10378x + 29535 0.9995 −8.17 5
rice y = 8657.3x + 2716.4 0.9998 −23.39 5
soil y = 11004x + 19222 0.9993 −2.63 5
Table 2. Accuracy and precision of the method in the seven matrixs.
Spiked Level (μg/kg)
Intraday (n = 5)
Interday (n = 15)
RSD (%)
Mean Recovery (%)
S-(-)-fenpropidin wheat 5 89.3 1.3 89.3 1.2 90.1 1.3 1.2
50 98.1 4.7 102.8 3.6 103.7 2.7 5.1
500 91.6 2.5 91.1 3.4 90.9 3.3 2.6
grape 5 91.9 4.2 94.8 3.6 97.7 1.4 4.6
50 92.5 1.6 93.3 3.0 95.2 2.9 2.7
apple 5 101.3 3.4 104.0 2.8 103.4 2.6 3.2
500 100.7 8.8 100.8 8.5 96.7 8.9 8.0
banana 5 83.2 4.0 80.7 3.0 78.6 0.7 3.9
soybean 5 73.3 2.2 74.4 1.7 74.8 1.1 1.7
rice 5 83.4 2.6 80.7 3.1 80.6 3.1 3.2
soil 5 85.8 1.8 85.5 1.9 82.9 2.6 2.8
1000 89.2 2.3 88.5 2.1 87.1 1.2 1.2
R-(+)-fenpropidin wheat 5 95.9 4.4 93.2 4.0 94.9 3.7 3.8
apple 5 97.8 0.4 99.2 2.1 99.1 2.1 1.7
banana 5 103.8 4.5 106.1 0.7 104.2 3.4 3.8
500 96.4 4.3 97.6 4.0 100.0 1.3 3.4
Li, R.; Zhang, Y.; Li, Y.; Chen, Z.; Wang, Z.; Wang, M. An Innovative Chiral UPLC-MS/MS Method for Enantioselective Determination and Dissipation in Soil of Fenpropidin Enantiomers. Molecules 2022, 27, 6530. https://doi.org/10.3390/molecules27196530
Li R, Zhang Y, Li Y, Chen Z, Wang Z, Wang M. An Innovative Chiral UPLC-MS/MS Method for Enantioselective Determination and Dissipation in Soil of Fenpropidin Enantiomers. Molecules. 2022; 27(19):6530. https://doi.org/10.3390/molecules27196530
Li, Rui, Yanqing Zhang, Yanhong Li, Zihao Chen, Zhen Wang, and Minghua Wang. 2022. "An Innovative Chiral UPLC-MS/MS Method for Enantioselective Determination and Dissipation in Soil of Fenpropidin Enantiomers" Molecules 27, no. 19: 6530. https://doi.org/10.3390/molecules27196530
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