Hayley Peterson is a reporter for Business Insider's retail section.
The burrito eatery's executives said Wednesday that the free food offers have been helping to drive traffic in the wake of two E. coli outbreaks that have sent the chain's sales plunging.
Known as the McBarge, the restaurant has been sitting in Canadian waters for nearly 30 years.
Ads are among the most recent in a series of similar videos posted over the past couple of weeks showing food at McDonald's being cooked and prepared.
The retail giant's latest move comes after several quarters of sales declines at its namesake stores.


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Iain Dale: The good plain old-fashioned party poster – driven out of politics by thuggery and fear
By Iain Dale
Follow @IainDale
Iain Dale: How Harry and Meghan sunk Barry Gardiner's Labour leadership bid
Iain Dale is Presenter of LBC Drive, Managing Director of Biteback Publishing, a columnist and broadcaster and a former Conservative Parliamentary candidate.
Amber Rudd, in her evidence to the Home Affairs Select Committee on Monday, declared that she was aware of individual cases related to Windrush children, but hadn't joined the dots and realised that something systemic had gone wrong.
I suppose I would gently ask how many cases does it take for the dots to be joined? Naturally, Labour are calling for her resignation, just as Tories would if they were in Opposition. The Home Secretary is arguing that she's best placed to sort it out – the very same argument that Gordon Brown used after the financial crisis. He got away with it. Will she?
In a week's time, we will know the results of the local elections. Yes, ladies and gentlemen, these are on – not that you would know it, given the lack of posters on show. I wonder if the day of the political poster is over. It's getting more and more difficult to persuade voters to display their political affiliations in their window. It's easy to understand why given the aggression shown on social media who advertise their political wares.
I don't think a poster display ever changed a single vote, but there's no doubt that seeing a good poster display energises a political tribe, and makes it feel good about itself. It also makes people realise that they are not alone in holding the views they do.
I well remember back in 1983 the poster display at the very left-wing University of East Anglia, where I was a student. The placed was plastered with Vote Conservative posters – much to the horror of the local Labour Party. It was the first indication that the two Labour MPs in Norwich were about to be beaten by two insurgent Tories.
Given that the BBC is supposed to be the guardian of public service broadcasting I was rather surprised to learn that they will not be doing a full election results programme on either Radio 4 or Radio 5 Live next Thursday.
They have also cancelled Andrew Neil's This Week programme. They will be doing a local election results show on BBC1, hosted by Huw Edwards, but with no role for Andrew Neil.
Bizarre – given that, on a night like this, Neil is surely one voice you really want to hear from. Anyway, the whole point of this section of my column is to tell you that I'll be hosting a six hour-long local election night show on LBC with Jacqui Smith from 10pm through until 4am, so I do hope you'll join us for at least some of it.
One of my jobs this week at Biteback was to convince a best-selling author that they should publish with us, rather than the much bigger publisher that they went to for their last two books. Given that our pockets aren't as deep as the publishing big boys, it's not necessarily the easiest of tasks – though it was the author that approached me, rather than the other way around.
So many authors are getting tired of the contempt which is displayed towards them by their publisher. Their main complaint is that they can never talk to anyone there. No one is ever at their desk, and the phone always goes to voicemail.
It's almost as if authors are an inconvenience to the publishing process. Even when they are as famous as this particular author is, they are made to feel like a small fish in a very large pond. Big publishers need to rediscover the personal touch, otherwise the trickle of authors seeping to independents will become a stampede.
I keep trying to think of a joke to make about Dominic Raab's ministerial diary secretary who was revealed in Thursday's Daily Mirror as a £750 a time high class hooker. Unfortunately, even my smutty mind has failed to come up with anything for you. She revealed that Dominic orders exactly the same meal for lunch from Pret every day – seemingly thinking that was very odd. Not half as odd as her activities, I'd say. Takes all sorts, I guess. No one could ever say she wasn't on her game…
I started with Rudd, so let me finish with her. Timing is everything in politics. Guess who was guest of honour at yesterday's Lobby Lunch in the press gallery? Yup, she is. When it rains, it pours for her at the moment. The thing is, she seems to take it all in her stride. Fortitude counts for a lot in politics. All she can do is take Churchill's advice and Keep Buggering On.
1983 General Election Amber Rudd MP Andrew Neil BBC BBC Radio Five Live BBC Radio Four Books Campaigning Conservatives Culture Gordon Brown Immigration Jacqui Smith Labour LBC Local Elections (general) Norwich Sir Winston Churchill Social Media This Week
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Iain Dale: If Johnson loses, we'll have a fourth Conservative leader in five years. Goodness knows who that would be.
Iain Dale: Now it's crunch time – will MPs who say they fear No Deal vote for the obvious solution?
Will Johnson get a Brexit deal done after all?
Iain Dale: Were it not for the fringe at each year's Conservative conference, what would be the point of coming?
Iain Dale: Beyond Westminster, Johnson's stock with the public remains high
Iain Dale: Swinson's revoke policy disincentivises more Conservative defections
83 comments for: Iain Dale: The good plain old-fashioned party poster – driven out of politics by thuggery and fear

redpajama_set_name: RedPajamaCommonCrawl


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'Suicidal' Sia Reveals She Had To Go To Rehab After Backlash To Autism Portrayal In Her Film Debut
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Home » Lifestyle » Here are the Biggest Moments You Missed on Last Night's 'This Is Us' While You Were Crying
Here are the Biggest Moments You Missed on Last Night's 'This Is Us' While You Were Crying
The This Is Us writers packed a whole lot into Tuesday night's one-hour episode. If your head is still spinning from everything that took place, you're not alone.
Just in Jack and Rebecca's storyline, fans learned that the man Rebecca was kissing on her front porch was her former high school sweetheart, Alan. She decides to skip out on a date with Jack for him, and then accepts Alan's offer to move to New York. But when she sees Jack again at a serendipitous meeting in a grocery store, Rebecca takes him back and tells him she wants to go on a road trip to LA.
Then, there's Kate, Randall, Kevin, Beth, Toby, and all of their life-changing decisions, like Kate starting her egg retrieval process, Randall's political endeavors, Kevin's trip to Vietnam, and Beth questioning her marriage after getting fired. This is only episode 3, folks.
Because so much happened, here are some of the moments you may have missed that teased what could be coming up next in season 3:
Alan's mom, Lois, essentially pushed Rebecca to go after Jack.
OMG ITS LOIS FROM MALCOLM IN THE MIDDLE #ThisIsUs pic.twitter.com/Q8WSnkilP3
Aside from being introduced to Rebecca's ex, Alan, we meet his mom, Lois. She has a sweet relationship with Rebecca, and they have an honest conversation about finding the right partner.
Lois tells Rebecca she settled down with Alan's dad, Bob, because he was "sweet and he was warm and kind," and that was "rare, and it's still rare." Rebecca immediately thinks of Jack when she hears this, and decides she needs to pursue him instead.
Rebecca reiterates on multiple occasions that she was a career woman, though, and always wanted to become a singer. So, it makes sense that she once questioned her path of settling down with three kids in season 2 when she tried to land a singing gig at a local lounge.
Bonus fact: The actress who played Lois is Jane Kaczmarek, best known for Malcolm in the Middle. Her name was also Lois on that show.
The dishes were an important motif throughout the episode.
In the beginning, a young Rebecca is shown helping her mom do the dishes and making a lasagna for her father while her dad sits in the other room and watches TV. The montage also depicts Rebecca's mother putting on makeup, cleaning, and taking her husband's hat — a sequence of scenes clearly meant to portray the expectations of women at the time.
Later on in the episode though, Rebecca and Lois — two women who both made clear that they were career-minded — stand by the sink next to a bunch of dishes. But instead of doing them, they're toasting with champagne in celebration of Rebecca's initial decision to go live with Alan and pursue her dream in New York.
By the end though, it's clear that Rebecca isn't going to settle in her career or with her love life. Rebecca ultimately chooses to turn down Alan's offer and take a risk with Jack. Showing that Jack and Rebecca are equals and symbolizing Rebecca choosing to forge a path of her own, the two take on a stack of dirty dishes together. To make the moment even sweeter, Rebecca asks Jack if he wants to go on a road trip with her to LA and he accepts.
There were clues in previous episodes that Randall and Beth's marriage had problems.
On the surface, Randall and Beth have always seemed like the perfect couple. But for viewers who have been watching closely, they may have noticed that Randall has a tendency to make big life decisions — like quitting his job, taking over the rental property, and now running for office — without talking with Beth first. Aside from this, it's become more apparent this episode that Beth feels like her problems and worries get pushed aside because she always has to be there for Randall.
Randall's father, William, tells her in a flashback scene, "There's going to come a time in your future when you need to be the soloist — put your needs front and center, make Randall hold down the root for a while. And when that time comes, Beth, I want you to promise me you won't just sit there silently, fiddling with your wedding ring like you're trying to remind yourself why you got married in the first place."
Awww Randall…look at your wife…she needs this moment. Stop talking! #ThisIsUs pic.twitter.com/T4V3J7wePV
But right after Randall tells Beth he's going to run for office, Beth is seen fiddling with her ring.
Randall says some variation of "scrambled" three times as Kate writes down how many eggs were retrieved.
"We've all been scrambling ever since, scrambling to keep him alive, scrambling for new ways to keep close to him," Randall tells Beth as an image of Kate writing down that eight eggs were retrieved appears on screen. "Scrambled" eggs is not a positive visual for viewers to see when discussing in vitro fertilization, so perhaps this was foreshadowing of how successful the process will be for Kate.
@NBCThisisUs did y'all REALLY have to have Randall say "scrambling" as Kate was writing "eggs"? #ThisIsUs
In the preview for next week's episode, Jack is holding a black soldier, who is likely the man adult Kevin reaches out to via email.
Around the end of this episode, Kevin writes an email to a former veteran who was in the war with Jack to learn more about his father's past in Vietnam. His name is Mr. Robinson, and it's apparent that he has lost his right leg. In a preview of a flashback scene for next week's episode, viewers see Jack holding on to a black soldier who appears to have been hurt.
Catch This Is Us on Tuesdays at 9 p.m. ET on NBC.
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Hiroshi Otsuki (født 23. april 1980) er en tidligere japansk fodboldspiller.

Han har spillet for flere forskellige klubber i sin karriere, herunder Kyoto Purple Sanga.

Eksterne henvisninger

Fodboldspillere fra Japan

redpajama_set_name: RedPajamaWikipedia


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Adam Lajeunesse
Lock, Stock, and Icebergs
A History of Canada's Arctic Maritime Sovereignty
University of British Columbia Press 2016
In April 1988, after years of failed negotiations over the status of the Northwest Passage, Brian Mulroney gave Ronald Reagan a globe, pointed to the Arctic, and said "Ron that's ours. We own it lock, stock, and icebergs." A simple statement, it summed up Ottawa's official policy: Canada owns the icy waters that wind their way through the Arctic Archipelago. Behind the scenes, however, successive governments have spent over a century trying to figure out how to enforce this claim and on which legal basis to assert Canadian sovereignty over Arctic waters.
In Lock, Stock, and Icebergs: A History of Canada's Arctic Maritime Sovereignty (UBC Press, 2016), Adam Lajeunesse, a Professor of Public Policy and Fellow of the Brian Mulroney Institute of Government at St. Francis Xavier University, guides readers through the evolution of Canada's Arctic sovereignty, showing how the Northwest Passage and the surrounding waters became Canadian. Listen to this engaging podcast to understand what inspired Lajeunesse to write the book, what are the main points of his argument, and how its insights are still relevant today.
Lavinia Stan is a professor of political science at St. Francis Xavier University in Canada.
Lavinia Stan
Also Hosted By Lavinia Stan
Ruti G. Teitel
Revisiting Marx's Critique of Liberalism
Igor Shoikhedbrod
Building Trust and Democracy
Cynthia M. Horne


Date of a message jumps when it is hevered over – Got an idea?
When I hover over a message, its preview changes length and its date jumps left and right. Looks like the entire column shifts repeatedly as I move my mouse. It seems confusing and slows Outlook down.
However, this beta is better:) think I'll keep using it:) Thank you!


A teacher who sexually assaulted a student in a school photography darkroom over a two-year period has been sentenced to five years' jail.
Paul Anthony Segar, 50, of Mount Waverley, went on trial for 10 sexual offences against a former student.
A jury found him guilty of eight, including indecent acts with a child under 16 and sexual penetration of a child under 16 under his care.
The victim, a student of Segar's at an eastern suburbs secondary college in the 1990s, was 14 when he grabbed her from behind and touched her thighs and groin.
County Court Judge Julian Leckie said Segar's offences involved a serious breach of trust.
"I find nothing within the evidence which indicates true remorse," he said.
Judge Leckie told the court the victim and Segar worked on developing photos in the darkroom for the school magazine.
The court heard Segar first approached the victim in the darkroom, putting his hand on her chest and running his hands up and down her pelvis when she was 14.
During the next two years he sexually assaulted her on a number of other occasions.
The woman reported the matter to police about eight years later and wore a recording device to meet him at a shopping centre in March 2006.
Segar was sentenced to five years in jail with a three year non-parole period.


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Staff Selects: Joel Schumacher
Previous post: Paul Thomas Anderson and The American Nightmare
Next post: Stuart Gordon's Trilogy of Self-Destruction
Posted June 27, 2020 by Staff
In memory of the legendary director and man who had more than 20,000 sexual partners, Joel Schumacher, this week we are taking a look at some of his greatest films.
A Time to Kill
Joel Schumacher had a real talent for taking any genre and making it his own. A Time to Kill, his second attempt at adapting a John Grisham novel and capitalizing on the 90s wave of legal thrillers, is a prime example of that. With a case that bears more than a few similarities to the one in Anatomy of a Murder, concerning a man who took justice into his own hands and a lawyer trying to let him walk free through claiming temporary insanity, there's plenty of room for overworked courtroom drama. It is a racial aspect however, with the accused killer being a Black man who murdered two white men who beat and raped his daughter, that leads to most of the film's drama and more potent messages, as racists band together to oppose a verdict of not guilty and launch a number of violent attacks. The film doesn't always go into the depth on issues that might have served it better, instead opting for dramatics and cinematic presentation, but nevertheless, it presents a compelling story illustrating the flaws inherent to the American justice system that would punish some people more harshly for lesser crimes while denying them a fair trial by their peers and bulldozing anyone who attempts to fight for true justice. A Time to Kill is often a moving event to watch unfold and a testament to Schumacher's control as a director. [Henry Baime]
Batman and Robin
Joel Schumacher's Batman & Robin is a better film than any entry of Christopher Nolan's Dark Knight trilogy. There, now I've got your attention. The unfairly maligned final part of the Batman film series that started in 1989 was trashed by critics and nerds for being unapologetic and bold in its camp. And what camp! No superhero film since has come close to its level of unabashed extravagance, where the costumes, sets, and lighting bring the pulpiest concepts of Batman to life. It's all here: the bat nipples, the bat credit card, rubber lips, and an entrance by Poison Ivy at a party worthy of RuPaul's Drag Race.
All these years later, the major Batman films following this cinematic celebration of the inherent queerness of the Caped Crusader has been smothered in self-importance by two of the most heterosexual filmmakers currently working. It has been a slow march of dourness, stripping Batman of what makes him special: the oddities of a multibillionaire who runs around at night in a leather or spandex costume fighting crime, one that lost his family and then built a family of his own choosing. Schumacher understood these aspects and ran with them, bringing a truly unique and special touch to what would be an otherwise trite superhero flick.
Alas, it looks like that won't be coming back any time soon. We'll still have this bizarre, out-and-proud gem to cherish, but in the meantime, say it with me: #MakeBatmanGayAgain. [Cole Duffy]
The Lost Boys is the perfect example of a short lived stint of 80s horror that would serve as a gateway for many young adults into the genre, even generations later. It strikes a perfect balance between the fearful and comedic, the goofy desperation of the kids contrasted with the fierce and cult-like behavior of the older vampires. Schumacher schlock is on full display here as the vampiric Kiefer Sutherland dominates the screen, oozing charisma as leader David. Much like similar films of the era, The Lost Boys has a childlike energy to it, the fear of the unknown compounded by the naive belief that there is an easy way out. Here that childlike whimsy is put together with the story of an older brother who gets caught up with the vampires, increasing the tension as David terrorizes the entire Emerson family. It makes sense then that the entire family plays a role in the climax, instead of the old "parents aren't around" trope that terrorized genre films of the time for convenience's sake. It's a highlight of its time that has aged incredibly well. [Jen]
Fast-talking publicist Stu Shepard picks up a ringing pay phone in Times Square. The caller threatens to kill him if he hangs up the phone. It's a simple and brilliant high-concept premise—written by legendary filmmaker Larry Cohen and initially pitched to Hitchcock—which immediately grabs the audience's attention, but unlike many other real-time thrillers which eventually lose steam, Phone Booth manages to sustain the tension from the moment Stu picks up the phone through the film's final minute, largely due to Schumacher's impressive, kinetic filmmaking, and Colin Farrell's magnetic performance (in one of his earliest major roles).
Through the frenetic editing and blaring sound design/mixing, Schumacher depicts the loud city streets of New York City, and by contrast, Matthew Libatique's dynamic cinematography instills a sense of claustrophobia in the phone booth, crafting a locked-room thriller in America's biggest city. Farrell is perfectly cast as the arrogant PR agent who gradually unravels over the course of the film's compact 81-minute runtime, with Forest Whitaker and Kiefer Sutherland providing excellent supporting roles as well. Joel Schumacher's filmography is filled with underappreciated gems, and Phone Booth is one of his strongest.[Kern Wheeling]
Blood Creek
I have been itching to rewatch this hidden Nazi-occult horror film starring Shea Whigham, Dominic Purcell, Henry Cavill, and Michael Fassbender, for some time. Unfortunately being under sad circumstances, I figured Joel Schumacher's recent passing called for this revisit of the strangest entry in his eclectic filmography. You read that right, Cavill and Fassbender do star in this 2009 film where the latter plays a Nazi officer sent by Himmler's dark arts unit to track down ancient nordic runes left behind by Vikings when they first discovered North America. You'd think Fassbender would be above such a seemingly low-budget practical effects gore-fest— having just come off of Hunger, Fish Tank, and Inglourious Basterds—but under all that monstrous make-up and scarred-silicone, he looked to be having a blast. Blood Creek seems like it'd come from a Guillermo del Toro/Clive Barker collab, but it is written by recent Luca Guadagnino scribe, David Kajganich (A Bigger Splash, Suspiria). There's nothing technically outstanding, but it just serves to bolster Schumacher's ability to work in almost any genre—be it cult, locked-room thriller, comicbook, war, psychological, sci-fi, true story, romance, or courtroom. What we get is a lean, mean, 90 minute bloody affair that fits alongside the likes of Outpost and Overlord, and the atmospheric-conceptual blend of video games Resident Evil 4 (especially David Buckley's eerie score) and Call of Duty: WWII zombies. A solid recommendation for fellow fans of cult movies and Clive Barker.[Lee]
Staff Selects a bigger splash alfred hitchcock anatomy of a murder batman and robin blood creek christopher nolan clive barker colin farrell david kajganich fish tank forest whitaker guillermo del toro henry cavill hunger inglourious basterds kiefer sutherland larry cohen luca guadagnino michael fassbender outpost overlord phone booth shea whigham suspiria the lost boys


Comfort and glamour in one great wardrobe piece! It's the perfect alternative to a dress. Pair it with heels, flats, or a pair of tennis shoes...this is one of those pieces that you can wear any way and make it your own. Casual or dressy! Plus it has pockets!


Talking scale has a 550 lb weight capacity with an extra wide, stable weighing platform. Tempered glass top. There is a two-person memory feature, pleasant and easy to hear voice, tap on/off auto functions, large LCD display and a low-battery indicator. Great for visually impaired.


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Fridolin Andrewert (Frauenfeld, 19 de setembro de 1828 – Berna, 25 de dezembro de 1880) foi um político suíço. Foi membro do Conselho Federal suíço de 1875 a 1880.

Biografia
Ele foi eleito para o Conselho Federal da Suíça em 10 de dezembro de 1875 e foi membro do Conselho até 25 de dezembro de 1880. Ele era filiado ao Partido Democrático Livre da Suíça.

Durante seu mandato, ele ocupou o Departamento de Justiça e Polícia e foi Vice- Presidente da Confederação Suíça em 1880.

Em 7 de dezembro de 1880 foi eleito Presidente da Confederação Suíça para o ano de 1881. Imediatamente após a eleição, uma campanha desagradável estourou na imprensa, em particular sobre os hábitos alimentares do solteiro obeso, mas também rumores de que ele era um visitante regular em bordéis gays. Atraído por exaustão física e depressão severa, Anderwert suicidou-se no dia de Natal de 1880 no "Kleine Schanze", um pequeno parque próximo às Casas do Parlamento. A única frase publicada de sua carta de despedida afirma: "Eles querem uma vítima, eles a terão".

Mortos em 1880
Políticos da Suíça
Membros do Conselho Federal suíço


"The man is out there again".
She means the man who walks his dogs behind our house each day, in the morning or early afternoon. She has told me about him on a number of occasions but for whatever reason I only saw him myself for the first time a few days ago. I stand on the patio bench and peer through the grille of the upper wall. Two leads for two small dogs who trot along peaceably, pausing here and there, as dogs do, to sniff or mark a pole, and always, alongside them or just behind and keeping them company all the way with perfect, leash-free discipline, a tabby cat.
A white horse in the long grass that backs the beach. It would take a master to paint the scene above it; the hazy veil of a dirt grey horizon thins low in the sky, revealing a creamy ripple of higher cloud that expands as it arches overhead – little tufts pulled apart like the fibres of a cotton wool roll, white as the animal grazing. When I pass by again, some minutes later, the scene is gone, the clouds stage left as if dragged there by jaded stage hands. The show is over. It rains heavily the following morning and afterwards the horse isn't even a horse, but a white yacht gleaming in a spot of sunlight against a charcoal waterline.
In the passenger seat on the Avenida José León de Carranza, that becomes Avenida Cayetano del Toro,that becomes Avenida Andalucia: a long, long boulevard that dissects the lego-like neatness of the handsome new city. On either side the apartment buildings – motley yet somehow uniform in their array of olive greens, powder blues, peaches and champagnes, the cleans lines and soft, sun-smeared curves, the hospital, the hotels, the old church – recede in a tree-lined symmetry toward a vanishing point which, when reached, is cobbled, fortified and old; we turn towards the water and drive along it on the Avenida Campo del Sur, dazzled by the golden sparkle of the cathedral dome, then park and it's into the warren, the casco antiguo, unique in Spain and the world. A Salzburg with palm trees, a Prague where parrot-like tropicals flit from tree to tree in the teaming canopies that cover sultry hot squares.
There's a soft roar to the blue burn of the quemada, bright in a blacked-out room as it sweeps around the curved inside of a little cauldron, driven inward as it shoots out and upward – a closed tulip of gentian fire: electric, fluid and fast. And through the sapphire blaze a ladle swings and scoops in circles and figures of eight, unsettling almonds and orange peel and now and then lifted to pour blue fire from a height. The gallega that wields it sings some old gallego song, and if I listened hard enough I might understand the words. But I don't; there is no effort – I am lulled and slow and easy, and there is just the melody and the flame.
At the bus stop on the busy port road in Algeciras, waiting to go home, I see him emerge from an underpass on the other side. A face I'm familiar with from the bar behind me: one of the local boys – men of a certain age who gathered there for dominoes and banter when the old dueños still ran the place. He's dressed for exercise – some tight sports shorts and running shoes – but he looks a little awkward with it, his grey socks pulled up on his legs in the way you don't see much anymore, especially with trainers, and a body warmer on that calls into question his commitment to breaking a sweat on this fresh but fairly mild evening. His hair is long but he's bald on top and looks self-conscious – I think I see him glance across a couple of times to check that I'm not looking, and I feel a little bad for him – unlikely in his gear and clearly feeling uncomfortable. After a few seconds of having my attention distracted by the traffic, my eyes rest on him once again now that he's walked on a bit and up towards the coast on the pedestrian path that turns that way at the roundabout and, now that he's away from prying eyes on the main road I see him break into his run, and there's just something about it. Something uplifting. There he goes – fighting it off, not going gentle into that good night, and although I might claim to wear my socks with a little more aplomb, that makes him the same as me. I want to pat him on the back. Tell him "well done".
In the castle, a princess. Out on the water at the end of a causeway – a manmade isthmus that pokes out from a city built on a natural one, the end of it fortified, like most things on this coast. A novelty for us to be on the water and not battered by tarifeño winds. The city skyline low and pixelated with roof terraces and the towers the merchants put on top of their houses. Only the churches and some port paraphernalia poke upwards. The little girl in her brilliant white dress poses happily in an archway while her family photograph her and we stand to the side, waiting.
E is madrileño. He's only been in Tarifa for three months, but the work is coming in. He writes slowly and laboriously as I watch – "But morning overtook Shahrazad, and she lapsed into silence". The moment, as each of a thousand dawns approached, when the vizier's daughter faced her own end and escaped it. The rising sun a perfect expression of her power and powerlessness, a suspended moment of hope and resignation, the breath of the narrator, in and out. A punctuation of life and death in the telling of tales. No better story than this story of a storyteller, and so I watch happily as E gives the moment some permanency in fluid Thuluth script, writing it slowly and with great care in jet black ink with a needle, on my arm.


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Take a Trip
Hands and Feet Project – Mission Trip to Haiti
"The wonderful work the folks of Hands and Feet do in Haiti is something that the Ramsey Family Foundation is proud to support. Truly the hands and feet of Christ moving in ministry.""
— Dave Ramsey, #1 Best Selling Author
"The Tim Tebow Foundation has been blessed to come alongside the Hands and Feet Project in caring for Haiti's orphaned children. Being on the ground in Haiti and witnessing the way they operate, it's evident Hands and Feet is committed to bringing Faith, Hope and Love to some amazing kids and families in need."
— Tim Tebow, Founder and Chairman of the Tim Tebow Foundation
Follow along @hafproject
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HC at Pitt
6 Campus Organizations to Join if You're Looking to Make Friends
By Kelly Dasta • Pitt Contributor September 11, 2017 at 12:00pm
Making friends in college can be hard. For maybe the first time in your life, you're in a sea of people you don't know and you can't seem to remember how you made friends when you were a kid. This can be especially difficult if you go to a big school like Pitt. If you're a freshman or an upperclassman looking to expand your social circle, you've probably heard that you should join a club. But what club should you join if you're looking to make friends? Look no further than here:
1. A club relating to your major
This is one of the most beneficial ways to make friends. Not only will you meet people who share a common interest with you, but you will meet people in your field! As a result, you'll have plenty to talk about, while networking and helping each other with assignments at the same time.
2. A club relating to one of your passions
This is also a no-brainer. If you have something in common with someone, you're more likely to strike up a conversation. If you like theater, try out for a play. If you like animals, join an animal lovers club. If you like music, join a music club. There's probably a club on campus that suits at least one of your interests
3. Greek life
Greek life is a great way to meet friends. When you rush a Greek organization, you're paired with people who have similar values as you. They also have tons of events other than parties, such as philanthropy work, bonding events, and study groups. And if social Greek life isn't your thing, join an academic or service Greek life organization! You'll still find people who share your values, and you'll still have tons of activities to do with them.
4. A club sport
A club sport is a great way to make friends because in a sport you have to work together and communicate. You don't even have to be athletic or on a D1 team. Join an intramural team or start a pickup game with your floor mates or classmates who are probably just as skilled at sports as you are.
5. A club for your identity
If you identify with a certain race, sexual orientation, gender or identity, there's probably a club for others just like you! You can meet people who are like you and perhaps have had some of the same experiences you have, and you can have a safe space to turn to if needed. Examples of these could be a women's organization, a rainbow alliance/LGBTQ pride club, black action society, ect.
6. Your Her Campus chapter!
Of course, who could forget your school's Her Campus chapter? You'll be surrounded by an amazing group of women who are friendly and unique. You don't even have to like writing — you could join HC's Public Relations or Social Media team. Also, HC hosts tons of events, like at HC Pitt, we have a late-night cookie sale, Her Campus Night Out, group dinners, fundraisers, you name it.
You can easily find friends if you join any of these clubs, but most importantly, when joining any organization, you get out what you put in. Help out as much as you can. Go to multiple events and introduce yourself to people. No matter where you join, being involved is what makes the difference.
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Kelly Dasta (Pitt '18)
Kelly is the President/ Campus Correspondent at HC Pitt. She is a senior double majoring in English writing and communication rhetoric while pursuing a certificate in digital media. Writing has always been a passion of hers, and she hopes to work in book publishing and a best-selling author one day. She works as a tutor at Pitt's Writing Center and an intern at Creative Media Agency Inc. In her free time, she works on her novel, reads stacks of books and explores Pittsburgh with her friends.
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As I reflect on what my 7 L.O.C.S. on my right side of my head represent in this photo is weakness and thinness.
But with the use of my product 7 L.O.C.S. – Love of Crown Strength I pray to see growth and thickness of my 7 L.O.C.S. strands of hair with the use of essential oils.
That's nice. Do you use a specific product? Daily, or weekly to encourage growth.
Yes, I have a product that I had formulated. I will be selling soon.


What would you do if you were traveling in a foreign country and all of a sudden had all of your money taken from you?
Turkey is a country that is uniquely located in both Europe and Asia. It is bordered by Greece and Bulgaria to the west, Georgia to the northeast, Armenia, Azerbaijan and Iran to the east and Iraq and Syria to the southeast. Turkey also has coastline on the Mediterranean Sea, Black Sea and Aegean Sea.


text:
The Trump disaster: the chickens come home to roost
Written by John Rees
Published in Analysis
US President Donald Trump. Photo: Flickr/ Gage Skidmore
How did America elect its most reactionary President ever, asks John Rees
Let's not waste any more time than is absolutely necessary describing Donald Trump. The 45th President of the United States is a reactionary populist, a racist and a misogynist. This we know. The important question is why did it happen? Let's look at the causes:
1 Hillary Clinton. This was Clinton's election to lose and she lost it. Faced with an insurgent, anti-establishment populist, the Democrats ran the candidate most likely to build the Trump vote. The millionaire, ultra-establishment figure from a dynastic Presidential family must have been the opponent that Trump had dreamed of running against. But we can put the same point another way: Bernie Sanders could have, and if the polling is right, would have beaten Trump. To beat a fake anti-establishment populist right winger would have taken a genuine left-wing anti-establishment figure who, let's not forget this, made the term socialist popular among hundreds of thousands of Americans.
2 Barack Obama. This election is the only assessment of the Obama presidency that matters and it reads: 'you didn't do enough'. Obama's White House was the nearest that real life was ever going to get to the West Wing dream of a liberal presidency. But just not being George Bush was not enough. A weak healthcare system, the best of the Obama presidency, was not enough to make millions of Americans feel that enough was being done to repair the generation long disaster of neoliberal economics. Just not repeating Iraq, especially when Libya was a disaster that played so well for Trump, didn't look like the War on Terror was over.
3 The Republicans. From Sarah Palin and the Tea Party to the semi-automatic machine-gun-toting militias, the Republicans have fed the extreme right during the Obama presidency. They fed the racism towards America's first black president. The fed the gun culture. The Republican establishment turned against Trump at the last moment, but he is very surely their monster.
4 The political system. Noam Chomsky famously described US politics as a totalitarian system with two different factions. The myth is that 'any boy can become President'. The truth is that only millionaire boys with millionaire backers can become President. Much more than in Britain, it's evident that whoever you vote for you get the same free market economics at home and the same imperial wars abroad. Trump is an illusory alternative to all that, a mere rhetorical pose of an alternative. But in the arid desert of US political debate that was enough… for now.
5 It's the economy, stupid. Clinton lost this election in the rust belt states. When Trump said 'it used to be that they made cars in Flint and you couldn't drink the water in Mexico, but now they make cars in Mexico and you can't drink the water in Flint', it resonated. Big time. This is an economy in which for the last 40 years all gains in household income have gone to the top 20 percent of households. For the last 20 years, dividends and capital gains have grown faster than wages, and that's after tax. Real wages have declined so far that it takes two wages to provide the same standard of living as one wage provided in the 1970s. Meanwhile productivity is soaring. People are working harder and longer for less. No wonder nostalgia for an imaginary past where 'America was great' appeals to them.
The threats are obvious. Trump could turn his support base into an active and organised reactionary popular movement that smashes up black and migrant communities, the labour movement and the left. But he has difficulties in moving down this path.
Firstly, he is a maverick member of the establishment he pretends to hate so much. And, like every US President, the structural establishment control over his office will be considerable. The Fed, the CIA, the NSA, the Pentagon, corporate power and many other institutions will determine policy. An establishment figure like Clinton would have had her own power bases and resources within these institutions. Trump is a maverick who does not have these resources to the same degree and may be more malleable, as well as less predictable, for that reason. The US ruling class have a President they don't want, and that will make politics unstable but not necessarily easy for Trump.
Secondly, the American working class has got a President that half of them detest and who cannot deliver for the other half that put their faith in him. This will add to the instability as Trump tries to survive the hostility of considerable sections of both major classes. He can do it of course. Some in the ruling class will seize on a Trump presidency to hurry on with their own projects of increased exploitation at home and further war abroad. But there will also be opportunities for resistance in a system now widely understood to be fundamentally broken.
The Black Lives Matter movement has produced a level of resistance not seen since the 1960s in black communities. Trump's visceral attacks on Latin Americans has politicised that community. Bernie Sanders, only a few months ago, was pulling rallies far exceeding the scale of Trump events. Sanders made socialism a usable ideology for the left on a scale unseen since the 1960s. A non-sectarian left can use these points of resistance in a crisis-ridden political system to redirect the wave of anger at the real enemies of the US working class.
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Tagged under: NATO Working Class United States Democracy
John Rees
John Rees is a writer, broadcaster and activist, and is one of the organisers of the People's Assembly. His books include 'The Algebra of Revolution', 'Imperialism and Resistance', 'Timelines, A Political History of the Modern World', 'The People Demand, A Short History of the Arab Revolutions' (with Joseph Daher), 'A People's History of London' (with Lindsey German) and The Leveller Revolution. He is co-founder of the Stop the War Coalition.
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Corbyn suspension: seven lessons of the Starmer witch-hunt
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The Assange case: the people have the power


text:
\section{Introduction}
\label{sec:Introduction}

There are numerous concepts that describe the notion of coherent behaviour in time-dependent flows \citep{peacock2010introduction, hadjighasem2017critical}. The Eulerian framework for coherent structure detection typically consists of mapping Lagrangian particle tracking (LPT) data onto a grid to obtain a region in space in which computations of the velocity gradient tensor take place. The concept of Lagrangian coherent structures has also been proposed to identify material surfaces in a velocity field that extremize a certain stretching or shearing quantity \citep{haller2000lagrangian}. Compact groups of trajectories in flows have also been identified through clustering techniques \citep{froyland2015rough}, which revealed to be a useful tool even for incomplete trajectory data. Nonetheless, for a flow with largest length scales on the order of $D$, the array of current coherent-structures descriptions listed above (see algo \citep{banisch2017understanding, padberg2017network}) requires access to LPT data of mean inter-particle distances of $\sim \mathcal{O}(D \times 10^{-2})$ or less, which is not readily available in many \textit{in situ} engineering and biological flows \citep{schmale2015highways,shuckburgh2009robustness,davis1991observing,fujii2019observing}. Hence, the need for techniques to analyse sparsely-distributed track data persists. In this study, we discuss an alternative concept for coherent-structure detection based on Voronoi tessellation and graph clustering that has potential to detect coherent motion in realistic, sparsely-seeded fluid flows.

To avoid the inherent challenges associated with experimentally-acquired LPT data (e.g., sparse and inhomogeneous track sending), new approaches based on spectral clustering techniques have been assessed. Among these, one of the most promising techniques for applications with realistic, naturally-occorruing particle distribuitions is the Coherent-Structure Colouring (CSC) approach, originally tested by \citet{schlueter2017coherent}, and critically assessed by \citet{schlueter2017identification}, \citet{schlueter2019model}, and \citet{husic2019simultaneous}. The CSC algorithm adopts spectral graph clustering theory to colour-code LPT data based on the kinematic dissimilarity between all pairs of particles. The major advantage of such approach if the fact that the number of clusters (coherent structures) present in the flow does not need to be determined \textit{a priori}, avoiding the need of biased inputs from the user, such as needed in classical clustering approaches, e.g., $K$-means and fuzzy clustering, widely adopted in the literature \citep{saqib2017detecting,zhao2020k,hadjighasem2016spectral}.  Nonetheless, the CSC technique presents limitations when adopted to data sets from real-life applications: the CSC approach requires data-sets comprised of tracks of equal length, which is infeasible in most experimental settings. Moreover, since particles in the CSC approach are viewed as scattered, discrete points in space, the vast majority of the physical portion of the fluid domain is left empty, making diagnostics difficult to interpret for sparse seeding distributions. Nonetheless, as for the array of techniques listed above, the CSC approach was also found to have limited value for mean inter-particle distances of $\sim 0.15D$ or greater \citep{martins2021detection}, which restricts the analyses of coherent structures in challenging applications \citep{dimarco2005statistical}, motivating the current study.

\begin{figure}
  \centering
  \def\columnwidth{\columnwidth}
  \input{./figures/Schematics.pdf_tex}
  \caption{Schematic of coherent-structure detection based on Voronoi tessellation and graph clustering. Voronoi diagram is built from the Delaunay triangulation of the seeding particles. Neighbouring Voronoi cells are then identified through the Delaunay triangulation of the tracer distribution. Neighbouring time of Voronoi cells acts as a higher-dimensional criterion for particle clustering, and coherent structures are identified as the clusters of Voronoi cells that persist for longer periods of time as neighbouring cells.}
  \label{fig:Schematics}
\end{figure}

In the present study, rather than viewing a fluid parcel as a means for discretization, we employ the simple concept that a seeding particle, with its associated position and momentum, is representative of a volume of the fluid flow \citep{espanol2009voronoi, rosi2015lagrangian, padberg2017network, krueger2019quantitative}. One of the most natural ways of assigning volume to a tracer is through a Voronoi tessellation \citep{neeteson2015pressure}. The technique proposed in this study employs a Voronoi tessellation to detect neighbouring particles in the flow, using the period of time a pair of Voronoi cells persist as neighbouring cells, referred to here as their \textit{neighbouring time}, as a metric for coherence. The algorithm then employs spectral graph clustering theory to compare the neighbouring times of an arbitrary number of Voronoi cells, colour-coding them based on the period of time they share a common Voronoi edge (as shown in Fig. \ref{fig:Schematics}). In practice, Voronoi cells that present relatively long neighbouring times are colour-coded with similar colours. Since the neighbouring time is independent of reference frame, the tesded technique is naturally objective. Moreover, like the CSC technique, the current approach is based on spectral clustering, which does not necessarily constrain the technique to a minimum number of data points, making it a strong candidate for the use with sparse LPT data.

Therefore, our first objective here is to prove and quantify the ability of the current technique to detect coherent structures in realistic LPT data. Towards this goal, the current approach is described and tested with synthetic data on the two-dimensional, mixing double-gyre flow, and then subsequently on challenging three-dimensional LPT data behind a bluff body at high Reynolds numbers. Coloured Voronoi cells from the current technique are then compared to CSC-coloured tracks, FTLE-fields, and to diagnostics obtained with the baseline vorticity fields. The outline of this paper is as follows. In section \ref{sec:Methods}, we review the concepts for defining coherence using topological properties of the Voronoi diagrams. This analysis is followed in section \ref{sec:Formulation} through the description of the adopted key normalized parameters for the evaluation of the current method. In section \ref{sec:Benchmarks},  we describe the adopted benchmark flows. In section \ref{sec:Results}, analysis of the technique is performed with changes in the normalized parameter space. Lastly, conditions and limitations for the use of the technique with three-dimensional LPT data are established in section \ref{sec:large_scale_exp}

\section{Methods}
\label{sec:Methods}

The following section is organized as follows. In section \ref{sec:Formulation}, the mathematical description of the proposed method and adopted notation are presented. Subsequently in section \ref{sec:Parameters}, we explain the normalized parameter space for the analysis of the current technique.

\subsection{Mathematical description}
\label{sec:Formulation}

This section presents the mathematical description of the proposed technique. Key steps of coherent-structure detection within the technique's framework are also schematically represented in Fig. \ref{fig:Diagram}. Consider the instantaneous seeding of $N$ particles, $p_i$ ($i \in I_N =\{1,2,\cdots,N\}$), in $m$-dimensional Euclidean space, $m \in I = \{2,3\}$, with location vectors $\mathbf{x}_i$. The Voronoi diagram of $p_i$, $V(p_i)$, is such that for every point $\mathbf{x}$ in space, $\mathbf{x} \in \mathbb{R}^m$, a convex polygon, referred to as a Voronoi cell, $V_R(p_i)$, can be defined as a region in which $\mathbf{x}$ is a closer member to $p_i$ than to any other particle $p_j$ ($p_i \neq p_j$ if $i \neq j$) with location vector $\mathbf{x}_j$:

\begin{equation}
	V_R(p_i) = \left\{ \mathbf{x} \text{  s.t.} \parallel \mathbf{x} - \mathbf{x}_i  \parallel \leq \parallel \mathbf{x} - \mathbf{x}_j  \parallel \text{ for } j \neq i, j \in I_N \right\}.
	\label{Eq:Voronoi_cell}
\end{equation}

In Eq. \ref{Eq:Voronoi_cell}, $\mathbf{x}$ is any point within the fluid domain, and $V_R(p_i)$ encloses each particle into an individual Voronoi cell (see highlighted polygon in Fig. \ref{fig:Diagram}). The boundaries of such a polygon are referred to as Voronoi edges, $r_{ij}$ (see thick black lines in top-left panel in Fig. \ref{fig:Diagram}). The collection of all Voronoi cells at the time instant $t$, $V(p_i)$, given by

\begin{equation}
	V(p_i) = \{ V_R(p_1), \cdots, V_R(p_N) \},
	\label{Eq:Voronoi_diagram}
\end{equation}

\noindent
is the Voronoi diagram of the seeding distribution, $p_i$ \citep{ferrero2011voronoi}. Based on $p_i$, a network called a Delaunay triangulation, $DT(p_i)$, see dashed gray lines in top-left panel in Fig. \ref{fig:Diagram}, can be defined, where the vertices of the network correspond to particle positions, $\mathbf{x}_i$, and a triangle (i.e., a set of three edges) between three adjacent nodes is created if no other particles lay within the circumcircle area defined by the three nodes (see green circle in Fig. \ref{fig:Diagram}). It is evident from the definition of $DT(p_i)$ that Voronoi cells only share a common Voronoi edge when their associated particles are connected by a Delaunay edge \citep{chew1989constrained}. It is also axiomatic from the given definitions of $DT(p_i)$ and $V(p_i)$ that edges of the Voronoi diagram are normal to the Delaunay triangle edges.

\begin{figure}
  \centering
  \def\columnwidth{\columnwidth}
  \input{./figures/Diagram.pdf_tex}
  \caption{Schematics of coherent-structure detection based on Voronoi tessellation. Voronoi and Delaunay diagrams of the particle distribution $p_i$, $V(p_i)$, $DT(p_i)$, are represented in the graph space, $G(V)$, such that lengths of edges of $DT(p_i)$, $r_{ij}$, are converted into distances in the higher-dimensional eigenspace $G(V)$: $r_{ij} \rightarrow \mathcal{A}_{ij} \rightarrow \chi(\mathcal{L}(G))$. A Voronoi cell, $V_R(p_i)$, is highlighted in blue in the top-left panel. The top-left panel also highlights in green the triangulation of three particles intersecting a circumcircle with no particles within its interior.}
\label{fig:Diagram}
\end{figure}

Hereafter, we define neighbouring tracers, $p_i$ and $p_j$, all pairs of tracer particles that, at the $n$-th timestep, describe the two vertices of the $(i,j)$-th Delaunay edge (see particles highlighted in green in Fig. \ref{fig:Diagram}). The total neighbouring time, $n_{Tij}$, is subsequently defined as the total number of timesteps, $n_{Tij} \in [0,n]$, for which the $i$-th and $j$-th tracers persisted as neighbouring tracers. Based upon such definitions, the problem of coherent-structure detection is naturally reduced to that of finding groups of Voronoi cells that persist for higher numbers of timesteps as neighbouring cells, since the cells of two particles in a Delaunay edge are neighbouring cells. The present technique solves this last problem by adopting spectral graph theory \citep{spielman2007spectral}. Consider a graph $G(V)$ defined such that its $i$-th node represents the $i$-th Voronoi cell, whereas its $(i,j)$-th edge connects the $i$-th cell to its $j$-th neighbouring Voronoi cell. The weight (or length) $\mathcal{A}_{ij}$ of the $(i,j)$-th edge is defined as

\begin{equation}
  \mathcal{A}_{ij} = \left( \frac{1}{2} \right)^{n_{Tij}},
  \label{Eq:Adjacency}
\end{equation}

\noindent
where $\mathcal{A}$ consists of a full matrix referred to as the adjacency matrix of the graph $G(V)$. From the definition in Eq. \ref{Eq:Adjacency}, it is clear that the length of the $(i,j)$-edge is smaller for greater neighbouring times. Hence, long-lasting neighbouring tracers will be closer in the graph representation of the Voronoi diagram, $G(V)$, and are naturally clustered together. It is also evident that such graphs share the same topology of $DT(p_i)$, as shown in Fig. \ref{fig:Diagram}. Nonetheless, while edges of $DT(p_i)$ yield a physical distance between pairs of tracers, edges of $G(V)$ represent what we define as the \textit{kinematic distance} between the same tracer particles. Moreover, since the neighbouring time is a frame-invariant property, coherent structures obtained with the proposed technique are also objective \citep{haller2000finding}. It is also important to highlight the fact that the lifetime of Voronoi edges is volatile, hence contamination of results by track-breaking process is expected.

Central to the spectral clustering technique are also the definitions of the graph's degree matrix, $\mathcal{D}$, given by

\begin{equation}
  D_{ij} = \delta_{ij} \sum_{k=1}^{N} {A_{ik}},
  \label{Eq:Degree}
\end{equation}

\noindent
where $\delta_{ij}$ represents Kronecker's delta function and the graph's Laplacian, $\mathcal{L}$, defined as

\begin{equation}
  \mathcal{L}_{ij} = \mathcal{D}_{ij}^{-1/2}(\mathcal{D}_{ij}-\mathcal{A}_{ij})\mathcal{D}_{ij}^{-1/2}.
  \label{Eq:Laplacian}
\end{equation}

 In Eq. \ref{Eq:Laplacian}, $\mathcal{L}$ is pre-normalized by $\mathcal{D}$. The corresponding eigenvalue problem that maximizes the differences between the Voronoi cell's neighbouring time is

\begin{equation}
  \mathcal{L}_{ij}X_j = \xi X_j,
  \label{Eq:eigen}
\end{equation}

\noindent
such that $\chi_j \equiv X_j(\xi_{\max})$, $j \in I_N=\{1,\cdots,N\}$, is the eigenvector with associated maximum eigenvalue, $\xi_{\max}$ \citep{schlueter2017identification}. Voronoi cells, $V_R(p_j)$, assigned with similar $\chi_j$ values are supposed to indicate spatio-temporal coherence. This coherence criterion is such that Voronoi cells that share a common Voronoi edge for longer flow times present a shorter distance in the higher-dimensional eigenspace (lower eigengaps), hence presenting coherent motion. In the proposed approach, coherent structures in the fluid flow are identified as regions in the flow with Voronoi cells of similar values of $\chi$ \citep{schlueter2017coherent}.

\subsection{Normalized parameters}
\label{sec:Parameters}

Considering a volume of fluid that scales with the characteristic length of the flow, $D$, and a homogeneous seeding distribution, accurate coherent-structure identification is assumed to be dependent on the number of tracers, $N$, present in the flow. Consider a flow with largest length scales $D$. Defining the characteristic period of the largest scales as $T$, coherence shall be visualized in normalized time, $t/T$. Moreover, the amount of Lagrangian information in the flow relative to $D$ is assumed to be proportional to the number $N$ of tracer particles tracked per characteristic length $D$, as denoted by $C=N/D^3$. Subsequent to the definition of $C$, here we define the mean inter-particle distance as

\begin{equation}
  \Lambda \equiv \left( \frac{3}{4 \pi C}  \right)^{1/3}.
  \label{Eq:Lambda}
\end{equation}

Accuracy of coherent-structure detection with the proposed approach is assessed by comparing results obtained within the technique's framework with results obtained from the baseline Finite-time Lyapunov exponents (FTLE) approach \citep{haller2000lagrangian} and with the state-of-art Coherent-Structure Colouring (CSC) algorithm \citep{schlueter2017coherent}. Both of these approaches will be summarized in the following paragraphs.

The FTLE measures the maximum linearised growth rate between initially adjacent particles. The FTLE approach is founded on the definition of the Cauchy-green tensor, $\mathcal{C}$, given by

\begin{equation}
  \mathcal{C}(\mathbf{x}_0) = \left( \nabla \mathbf{F}_{t_0}^{t} \right)^\top \cdot \left( \nabla \mathbf{F}_{t_0}^{t} \right),
\end{equation}

\noindent
where $\mathbf{F}_{t_0}^{t}$ represents the flow map, which operates over a fluid particle $p_i$ at $\mathbf{x}_{i,0} \equiv \mathbf{x}_i(t_0)$, $i \in I_N=\{1,\cdots,N\}$, and tracks the particle's position from an initial to a final state, $\mathbf{F}_{t_0}^{t} : \mathbf{x}_0 \rightarrow  \mathbf{x}(\mathbf{x}_0)$. Identification of coherent structures with the FTLE technique relies upon the definition of regions of highest eigenvalue $\lambda_{\max}$:

\begin{equation}
  FTLE_{t_0}^{t} = \frac{1}{|t-t_0|} \ln \left( \sqrt{\lambda_{\max}(\mathcal{C})} \right).
  \label{Eq:FTLE}
\end{equation}

In the FTLE framework, coherent structures are identified as barriers to fluid motion. Extrema values of $FTLE_{t_0}^{t}$ represent the locally more influential material surfaces. If integrated forward in time, extreme positive values represent the locally most repelling material surfaces, whereas opposite in signal extrema represent the most attracting ridges. Both material surfaces exchange definitions if the FTLE is integrated backward in time.

Moreover, $\chi$-coloured Voronoi cells will also be compared to the CSC-coloured tracks from the CSC approach. Similar to the currently-proposed technique, in the CSC framework the dissimilarities between a pair of tracer trajectories is represented by the adjacency matrix of the associated graph-clustering problem, $\mathcal{A}$, defined as

$$ \mathcal{A}_{ij} = \frac{1}{ \overline{r}_{ij} |t-t_0| }
\left[ \sum_n  (\overline{r}_{ij}  - r_{ij}(t_n) )^2 \right]^{1/2}, $$

\noindent
where $\overline{r}_{ij}$ represents the mean distance between the $i$-th and $j$-th particles.  The spectral clustering process based on the CSC approach follows from Eq. \ref{Eq:eigen} such that $CSC \equiv X(\xi_{\max})$. Results obtained with both the FTLE and CSC techniques for varying $\Lambda$-values will be used for comparison.

\section{Description of benchmarks}
\label{sec:Benchmarks}

\subsection{Algorithm verification via case study: double-gyre flow}

We specify an unsteady velocity field $u_i$, $i \in I = \{1,2\}$, the double-gyre flow, that has had extensive use as a test-bed for coherent-structure detection \citep{shadden2005definition,senatore2011detection, williams2015identifying, pratt2015reaction,  balasuriya2016barriers, balasuriya2018generalized}:

\begin{equation}
  \left.\begin{aligned}
    u_1 & = -\pi A \sin\left( \pi h(x_1,t) \right)\cos\left( \pi x_2 \right),\\
    u_2 & =  \pi A  \cos\left( \pi h(x_1,t) \right)\cos\left( \pi x_2 \right)\frac{\partial h}{\partial x_1}(x_1,t) ,\\
        \end{aligned}
  \right\}
  \label{Eq:double_gyre}
\end{equation}

\noindent
where

$$ h(x_1,t) := \epsilon \sin(\varOmega t)x_1^2 + \left( 1-2\epsilon\sin(\varOmega t) \right)x_1.$$

For a domain $\Gamma = [0,2] \times [0,1]$, $x_i \in \Gamma$, it is well-known that the topology of the flow comprises hyperbolic trajectories near $x_i = (1,0)$ and $(1,1)$, which move position for $\epsilon>0$ \citep{williams2015identifying}. In the present study, $A=1$, $\epsilon=0.25$ and $\varOmega  = 2\pi/T = 2\pi/10$. The characteristic length $D$ and velocity $U_\infty$ are such that $U_\infty/D=T$. Figure \ref{fig:double_gyre} shows the normalized vorticity field at different characteristic times $T$ for reference. The reference flow is simulated using a pseudo-spectral code with spatial resolution of $\Delta x_i/D = 0.01$, and was evolved with a constant timestep of $\Delta t/T=0.01$.

\begin{figure}
  \centering
  \def\columnwidth{\columnwidth}
  \input{./figures/Double_gyre.pdf_tex}
  \caption{Normalized vorticity fields for the reference double-gyre flow. The plots exhibit contours of normalized vorticity at different timesteps $t$ obtained with a grid of spatial resolution of $\Delta x_i/D = 0.01$.}
  \label{fig:double_gyre}
\end{figure}

\subsection{Case study: High-Reynolds-number bluff-body flow}

The second benchmark case tested in this study consists of LPT data behind a bluff body collected in the $24\text{ m} \times 9.1\text{ m} \times 9.1\text{ m}$ test section in the large low-speed wind tunnel at the National Research Council in Ottawa, Canada \citep{hou2021novel}. An overview of the raw-tracks data and resultant, interpolated vorticity field, are provided in Fig. \ref{fig:large_scale}. Tracks behind the bluff body are measured using a single-camera setup (Photron mini-WX 100, AF Micro-Nikkor $60\text{ mm}$ $f/2.8$, with the aperture set to 11) in a measurement volume of $4D \times 1.5D \times 1.5D$, where $D$ is the characteristic length scale of the flow ($D \approx 1\text{ m}$). Large air-filled soap bubbles generated with two commercial bubble generators (Antari B200) are adopted as tracer particles, yielding bubbles production rates of $\sim 80 \text{  bubbles/s}$. Soap bubbles with an average diameter of $\sim17.5\text{ mm}$ are illuminated by an array of four pulsed high-power LEDs (LED-Flashlight 300, LaVision GmbH). Characteristic wake-flow behind the bluff body at free-stream velocity of $U_\infty \approx 8\text{ m/s}$, yielding $Re \sim 6 \times 10^5$ based on the model's height, is assessed at a constant sampling frequency of $f_s = 150\text{ Hz}$. More details concerning the measurement process and general flow field are presented in \citet{hou2021novel}.

A total of 5718 bubble tracks are extracted from this large-scale measurement, whereas in the present study we filter out from the raw track data trajectories of temporal length $L_{s,min} \leq 9$ timesteps. The filtering process yields 1940 tracks of temporal length $L_{s,min} \geq 10$ timesteps. Figure \ref{fig:large_scale} represents raw pathlines and a reference-normalized vorticity field obtained from point-in-shell interpolation of the 1940 filtered tracer trajectories. We also highlight the fact that no smoothing or interpolation schemes are adopted to the reference vorticity field shown in Figure \ref{fig:large_scale}.

The analysis of the reference vorticity field indicates that tracks undergo a strong swirling motion due to the C-pillar vortex formed in the wake of the bluff body in yaw. Coherence detection from this LPT data is challenging due to a lack of tracks in the lower-left corner of the measurement volume and in the vortex-core region. Low tracer concentration in the vortex core region is associated with bursting of bubbles due to large pressure and shear-stress gradients near the centerline of the coherent structure. Strong advection outwards from the vortex core also yields inhomogeneity in the tracer distribution. The sparsity and non-homogeneous tracer distribution characteristics of the current data set allow for the assessment of a single C-pillar-like vortex structure in the track data. However, the coherent structure is hardly visible in the vorticity field due to the poor extraction of spatial-gradients achieved with this sparse data set, defined as $\Lambda \geq 0.13 $.

\begin{figure}
  \centering
  \def\columnwidth{\columnwidth}
  \input{./figures/Large_scale.pdf_tex}
  \caption{Raw tracks shown in top left. Reference normalized cross-flow vorticity field obtained from the point-in-cell interpolation of the tracer trajectories is shown in the bottom right. Raw reference fields (without smoothing or interpolation) are plotted in specific planes normal to the streamwise direction at $x_1/D = [-0.5,0.5, 1.5, 2.2]$. Results obtained have a constant bin size of $\Delta x_i/D=0.05$. The direction of the reference far-field velocity, $U_\infty$, and the characteristic length, $D$, are also illustrated.}
  \label{fig:large_scale}
\end{figure}

\section{Results and discussion}
\label{sec:Results}

\subsection{Double-gyre flow}

In the following section, the performance of the proposed approach is first assessed on simple, two-dimensional data from the double-gyre flow. Voronoi cells coloured with $\chi$-values are compared to the FTLE- and CSC-coloured fields in a side-by-side fashion. CSC- and FTLE-fields are re-scaled in all cases to the intervals $[-1,1]$ and $[0,1]$, respectively, to allow for direct comparison of results. We extract coherent structures using the proposed technique by simply re-scaling $\chi$ to the interval of $[-1,1]$.

The first analysis consists of comparing results obtained with the three approaches for decreasing mean inter-particle distance values, whereas the normalized flow time is fixed at $t/T=2$. Subsequently, the same analysis is repeated for a comparison of the current technique to the baseline vorticity field. Here, the objective is to perform a systematic comparison of the different techniques, using them on a test-bed flow in which a ground truth can be reasonably established. Nevertheless, due to the absence of a standardized method of quantifying the quality of coherent-structure detection techniques that are fundamentally different in nature, diagnostic tools in this study are compared purely through visual inspection.

In the present analysis, the number of tracers, $N$, ranges considerably ($N=36$, $64$, $100$, $196$, $484$ and $1225$), corresponding to mean inter-particle distances of $\Lambda \approx 0.24$, $0.20$, $0.17$, $0.13$, $0.10$ and $0.07$. In a recent publication, it was concluded that particle concentrations of $N/D^3 \leq \mathcal{O}(10^2)$ ($\Lambda \geq 0.13$) are insufficient for coherent-structure detection in boundary-layer or free-jet flows based on LPT data \citep{schneiders2016dense}. Hence, here we consider particle distributions of $\Lambda \geq 0.13$ as very sparse data sets. Tracers are homogeneously-seeded using the following procedure: in every test case, the domain $\Gamma_i$, $i \in I = \{1,2\}$, is split into bins of size $\Delta x_1 \times \Delta x_2 = \Gamma_1/N^{1/2} \times \Gamma_2/N^{1/2}$, followed by the seeding of a single particle into a random position inside one of the $N$ uniformly-distributed bins. After the homogeneous seeding of synthetic tracers, tracer trajectories are integrated using a second-order central scheme with timesteps of $\Delta t/T=0.1$ in $t/T \in [0,10]$. Test cases are summarized in Table \ref{tab:summary_dg}.

\begin{table}
\begin{ruledtabular}
    \caption{Summary of test cases for the double-gyre flow, where $N$ is the number of tracer particles and $\Lambda$ is the mean inter-particle distance.}
    \begin{tabular}{ccccccc}
    Case             & a    & b    & c    & d    & e    & f    \\
    \hline
    $N$              & 36   & 64   & 100  & 196  & 484  & 1225  \\
    $\Lambda\approx$ & 0.24 & 0.20 & 0.17 & 0.13 & 0.10 & 0.07 \\
    \end{tabular}
  \label{tab:summary_dg}
\end{ruledtabular}
\end{table}

Figure \ref{fig:double_gyre_results} presents the double-gyre flow for, from left-to-right, $\chi$-coloured Voronoi cells, FTLE- and CSC-fields. FTLE fields were computed by a Matlab software package developed by \citet{peng2009transport}. The algorithm can be summarized as follows: a third-order interpolation scheme is adopted to interpolate the flow map function, $\mathbf{F}_{t_0}^{t}$, onto a grid. Subsequently, spatial gradients are obtained through central differencing with neighbouring grid points. Lastly, the FTLE field is computed at every grid point based of Eq. \ref{Eq:FTLE}. CSC-fields are obtained through the mapping of the instantaneous seeding distribution onto two-dimensional Cartesian grids. The resultant field is then subjected to a robust spline smoothing algorithm developed by \citet{garcia2010robust}, which adopts a type-2 discrete cosine transform to assign missing data to values that are estimated using the entire dataset.  Moreover, we use this blue-green-yellow-red colour-scheme consistently for all diagnostic fields for ease of comparison. From the results shown in Fig. \ref{fig:double_gyre_results}, is it observed that without requiring specification of the number of gyres, the proposed technique was able to reveal physically-interpretable coherent regions for the sparsest test cases, at $\Lambda \approx 0.24$ and $\Lambda \approx 0.20$ (see cases (a) and (b), respectively, in Fig. \ref{fig:double_gyre_results}). Despite such low particle concentration, the two gyres can be identified in the flow as two regions in the Voronoi diagram coloured in red and blue, corresponding to the two extrema of $\chi$. In this case, the largest dissimilarity in the flow in terms of neighbouring time is between trajectories that started near the left and right quadrants of the double-gyre flow. At this same particle concentration, both the CSC and FTLE techniques were unable to provide physically-interpretable results.

\begin{figure}
  \centering
  \def\columnwidth{\columnwidth}
  \input{./figures/Double_gyre_results.pdf_tex}
  \caption{Selected cases for double-gyre flow at $t=2T$ with mean inter-particle distance values of $\Lambda\approx0.24, 0.20, 0.17,  0.13, 0.10, 0.07$ (top-to-bottom). Analyses are visualized by $\chi$-coloured Voronoi cells (left), FTLE-fields (center) and CSC-coloured fields overlaid by CSC-coloured tracks (right). Cases (a) to (f) are listed in Table \ref{tab:summary_dg}.}
  \label{fig:double_gyre_results}
\end{figure}

Further decreasing the inter-particle distance to $\Lambda\approx0.17$, for case (c), the boundary between the two distinguished regions in red and blue in the Voronoi diagram becomes well-defined, whereas no discernible pattern has emerged from the FTLE or CSC approaches. Two regions start to form in the CSC-fields only further decreasing the mean inter-particle distance to $\Lambda \approx 0.10$, for case (e), two regions start to form in the CSC-fields, which are evident from the two clusters of tracers somewhat reproducing the expected topologies of the two gyres. The fact that material coherence can be observed in CSC-fields with the particle concentration of case (e) agrees with observations of \citet{husic2019simultaneous}, who concluded that the CSC is expected to accurately reconstruct the two gyres of the double-gyre flow with a minimum number of tracks of $N\sim300$, or $\mathcal{O}(\Lambda) \leq 0.1$, representing a considerable progress towards sparser data sets when compared to classical gradient-based approaches.

By decreasing Lambda (cases (d), (e), and (f) of Fig. \ref{fig:double_gyre_results}) we observe the appearance of a different colour distribution for $\chi$. In fact, the two gyres are mainly characterized by intermediate $\chi$ values ($\chi \approx 0$) while the strongest (blue and red) $\chi$ values surround the two gyres. These first results reveal an important aspect of the tested technique: if sufficient particle concentration is provided, i.e., $\mathcal{O}(\Lambda/D) \ll 1$, dissimilar colours will inevitably be attributed to regions that act as barriers to fluid motion, since more particles tend to cluster in such regions, thus showing high neighbouring times. In cases of sparse particle concentrations (such as in cases (a) and (b)), $\mathcal{O}(\Lambda/D) \sim 1$, the dissimilarities will be simply attributed to tracks that were advected by the strongest coherent structures. Equivalently, such a result reveals that Voronoi cells coloured in dark blue rarely interact with tracks coloured in dark red. On the other hand, green regions could be expected to represent regions of more intense mixing. In the context of transport of passive scalars, for example, one should expect little to no mixing of the transported quantity between regions of the flow coloured with $\chi_{\max}$ and $\chi_{\min}$, which is a useful diagnostic for many natural and engineering flows. We also note that there is an analogy with FTLE field for low $\Lambda$ values, such that high $\chi$ values share a similar topology to the unstable manifold (high FTLE values) of the FTLE technique (see cases (e) and (f) in Fig. \ref{fig:double_gyre_results}, for example).

We repeat the comparative analysis using an Eulerian vortex criterion. Due to the simple topology of the flow, the vorticity field, $\bm{\omega} = \nabla \times \mathbf{u}$, is sufficient for this study. The $\omega$-fields are obtained as follows. The domain $\Gamma_i$ is divided into bins of size $\Delta x_i/D = 0.05$. Velocity components of the $(i,j)$-th bin are computed using the average velocity of the tracers within its domain, in a point-in-cell fashion \citep{garth2010fast}, whereas empty cells are assigned not-a-number (NaN). After mapping the reconstructed Lagrangian velocity to Eulerian space, the curl of the interpolated velocity field is computed such that partial derivatives are calculated using a second-order central difference scheme for interior data points, whereas first-order, single-sided (forward) difference schemes are adopted for points along the edges \citep{moukalled2016finite}. $\omega$-fields are also subjected to a partial reconstruction process using a linear interpolation algorithm \citep{henn2013comparison} that replaces NaNs in interior points by the arithmetic mean of the respective field variable in the adjacent cells.

\begin{figure}
  \centering
  \def\columnwidth{\columnwidth}
  \input{./figures/Double_gyre_results_eulerian.pdf_tex}
  \caption{Selected cases of double-gyre flow at $t=2T$ with mean inter-particle distance values of $\Lambda \approx 0.24, 0.17, 0.10$ (top to bottom) visualized by $\chi$-coloured Voronoi cells (left) and $\bm{\omega}$-field (right).}
  \label{fig:double_gyre_results_eulerian}
\end{figure}

Using the Eulerian approach for case (a), shown in the top-right panel of Fig. \ref{fig:double_gyre_results_eulerian}, the very sparse Lagrangian data (36 particles) does not allow for the velocity field to be reconstructed, as expected, whereas the two gyres can be identified as two clusters of Voronoi cells when using the current approach. For $\Lambda \approx 0.17$, corresponding to case (c), a noisy vorticity-field can be reconstructed from the LPT data. Concomitantly, the two gyres are physically distinguishable in the Voronoi diagram. Finally, for  $\Lambda \approx 0.07$, the strongest ridge is observed in the Voronoi diagram in the bottom panels of Fig. \ref{fig:double_gyre_results_eulerian}. At this particle concentration level, the two counter-rotating gyres are also easily distinguishable in the vorticity field.

\subsection{High-Reynolds-number bluff-body data}
\label{sec:large_scale_exp}

The second benchmark conducted in this study consists of three-dimensional LPT data collected behind a bluff body at a free-stream velocity of $U_\infty \approx 8\text{ m/s}$ ($Re \sim 6 \times 10^5$). In the current study, the total number of tracks in each test case is selected by imposing thresholded temporal track lengths of $L_{s,min}$, such that each analysed case consists of tracks of $L_{s} \geq L_{s,min}$ only. The analysis is conducted with $N=1940$, 289 and 70 particles, equivalent to inter-particle distances of $\Lambda \approx 0.065$, 0.12 and 0.20, respectively. We concluded from a preliminary analysis that both the CSC and FTLE techniques fail to provide physically-distinguishable flow features with such challenging LPT data and hence in the current benchmark, results obtained with the proposed technique are compared only to baseline vorticity fields.

In contrast with the two-dimensional Voronoi tessellation, three-dimensional Voronoi diagrams present complex topologies and make the visualization of coherent structures in LPT data quite challenging. We thus opted to omit the Voronoi diagram from the current section as well. Instead, the three-dimensional track data is colour-coded directly with the corresponding $\chi_i$ values. Subsequently, a point-in-cell interpolation is adopted to map the $\chi$-coloured tracks onto three-dimensional $\chi$-fields. The results of the proposed approach are then compared to normalized cross-flow vorticity fields, $\omega_1 D/U_\infty$. Both $\chi$- and $\omega$-fields are analyzed at three planes parallel to the cross-flow direction, at $x_1/D=[-0.5, 1.25, 2.5]$. A constant bin size of $\Delta x_i/D=0.05$ is adopted for the interpolation of the velocity- and $\chi$-fields, which are subsequently subjected to a partial reconstruction process using the robust smoothing algorithm developed by \cite{garcia2010robust}.

Results for the challenging three-dimensional bluff-body data with $\Lambda\approx0.065$ are shown in Fig. \ref{fig:large_scale_results_dense}, in which the left panel shows $\chi$-fields overlaid by $\chi$-coloured tracks of the current technique, and the right panel shows the vorticity field resulting from the mapping of LPT data onto a grid. As guaranteed by the analysis conducted with the double-gyre flow, the vortex boundaries of the C-pillar vortex are well-defined in the $\chi$-coloured tracks with the selected inter-particle distance value. In contrast, the vortex core, which is located near the center of these planes, can only be partially-visualized by the vorticity field.

\begin{figure}
  \centering
  \def\columnwidth{\columnwidth}
  \input{./figures/Large_scale_results_dense.pdf_tex}
  \caption{Left and right panels show $\chi$- and vorticity fields, respectively, obtained from the point-in-cell interpolation of the LPT data onto a grid. Results obtained with $\Lambda\approx 0.065$ at $x_1/D=[-0.5, 1.25, 2.5]$. Panel on left also shows $\chi$-coloured tracks.}
  \label{fig:large_scale_results_dense}
\end{figure}

Results for $\Lambda\approx0.12$ are shown in Fig. \ref{fig:large_scale_results_medium}. With a mean inter-particle distance of about one-tenth of the characteristic length scale of the flow, $\Lambda/D \sim \mathcal{O}(10^{-1})$, the Eulerian approach (right panel) lacks a nested sequence of smooth closed contours that allows for coherent-structure detection. Nevertheless, an intuitive visual inspection of the $\chi$-field in the left panel still picks up the convex, C-pillar vortex core at the center of the $\chi$-coloured track data.

\begin{figure}
  \centering
  \def\columnwidth{\columnwidth}
  \input{./figures/Large_scale_results_medium.pdf_tex}
  \caption{Left and right panels show $\chi$- and vorticity fields, respectively, obtained from the point-in-cell interpolation of the LPT data onto a grid. Results obtained with $\Lambda\approx 0.12$ at $x_1/D=[-0.5, 1.25, 2.5]$. Panel on left also shows $\chi$-coloured tracks.}
  \label{fig:large_scale_results_medium}
\end{figure}

Lastly, results for $\Lambda\approx0.2$ are shown in Fig. \ref{fig:large_scale_results_coarse}. Interpolation of the velocity field with a large $\Lambda$ value is naturally unreliable, indicated by the poorly-reconstructed vorticity field in the right panel of the figure. On the other hand, as shown in the left panel, boundaries of a convex structure representing the C-pillar vortex can still be partially visualized by the $\chi$-fields, indicating that coherent structures can be identified with the current technique despite the severe sparsity of the investigated experimental data set. Notwithstanding, due to the evident sparsity and non-homogeneous tracer particle distribution of the current data set, it is challenging at this stage to go much beyond a qualitative assessment of the results. Nonetheless, the current technique, in view of the results presented in this study, proves to be a strong candidate for the detection of coherent structures in realistic, very sparse LPT data.

\begin{figure}
  \centering
  \def\columnwidth{\columnwidth}
  \input{./figures/Large_scale_results_coarse.pdf_tex}
  \caption{Left and right panels show $\chi$- and vorticity fields, respectively, obtained from the point-in-cell interpolation of the LPT data onto a grid. Results obtained with $\Lambda\approx 0.20$ at $x_1/D=[-0.5, 1.25, 2.5]$. Panel on left also shows $\chi$-coloured tracks.}
  \label{fig:large_scale_results_coarse}
\end{figure}

It is important to highlight the fact that the analysed flow is a very challenging benchmark due to data gaps near the core of the C-pillar vortex. Data gaps in the interior of a vortex structure are a consequence of the intense drifting away of tracers from the vortex core due to centrifugal forces \citep{marshall2005particle}. In the analysed data set, strong shear is also responsible for the bursting of tracers (helium-filled soap bubbles) near the center of the C-pillar vortex \citep{faleiros2019generation}. The combination of both effects causes radial-dispersion of tracers and data-gaps along the vortex core, omitting or strongly dampening the coherent structure in diagnostic fields of gradient-based approaches, despite the average particle concentration of the data set (see vorticity fields in Fig. \ref{fig:large_scale_results_dense}, for example). Unlike the neighbouring times of particles advected by the mean flow, which are typically high, the complex advection processes of tracers in regions of high shear yields low neighbouring times. Differently from classical approaches, such contrast between the behaviour of particles inside and outside of vortical regions allows for the visualization of coherent structures using the tested technique even if the particle concentration in the vortex-core region is considerably lower (see results in Fig. \ref{fig:large_scale_results_dense}). Going forward, in the future development of the technique analysed in this study, concrete connections between specific values of $\chi$, and the repelling or attracting behaviour of the coherent structures, will have to be explored.

\section{Conclusions}
\label{sec:Conclusions}

A Voronoi-tessellation-based approach for detection of coherent structures in sparsely-seeded flows is tested. Neighbouring time of tracer trajectories, defined as the total flow time two Voronoi cells remain connected by a Voronoi edge, was adopted as a metric for coherence. The novel approach was tested with LPT data from a simple double-gyre flow and then with challenging LPT data behind a bluff body. The method was compared to CSC-coloured tracks of the CSC technique, FTLE ridges and to the baseline vorticity field. In this study, capabilities of coherent-structures visualization was evaluated using as a metric the inter-particle distance. It was concluded that, in general, higher accuracy in coherent-structure identification is obtained for decreasing inter-particle distances. For low inter-particle distance values, colour-coded Voronoi cells of the current technique were found to exhibit patterns that are strongly correlated to the attracting surfaces (unstable manifolds) of the FTLE technique. Moreover, the tested technique demonstrated great potential for applications of inter-particle distances, $\Lambda$, on the order of the characteristic length scale $D$ of the flow, i.e., $\Lambda \sim \mathcal{O}(D)$, whereas other techniques present limited value.

\begin{acknowledgments}
  DER acknowledges funding from the Early Researcher Award (Ontario). The authors would also like to thank Dr. G. Iacobello for the many insightful discussions and feedback on the manuscript.
\end{acknowledgments}

\nocite{*}

redpajama_set_name: RedPajamaArXiv


Home » Anesthesiologists » Mari-Paule Thiet, M.D.
Thiet graduated from the University of Texas Southwestern Medical School in 1985 and completed her residency in obstetrics and gynecology at the Parkland Memorial Hospital in 1989. She completed a fellowship in maternal and fetal medicine at the George Washington University Hospital in 1991. She is an associate clinical professor in the Department of Obstetrics, Gynecology and Reproductive Sciences at the UCSF School of Medicine.


text:
The 1930s Film Parodies Starring Only Dogs
The "Barkies" were popular with audiences, but drew ire from animal welfare groups.
by Stephanie Weber August 7, 2017
One of the Dogville Comedies stars studying a script. Culver Pictures, Inc./ Superstock
The early sound era of film was like the Wild West when it came to making movies. It was into this experimental milieu that a series of short films that used all-dog casts was produced between 1929 and 1931.
Professionally trained canines were the stars of the "all-barkie" Dogville Comedies. Metro-Goldwyn-Mayer produced the nine shorts as parodies of Hollywood's hits. The films were shot with silent film and dubbed over with human speech, utilizing the voices of the creators Jules White and Zion Myers, as well as their colleague Pete Smith. According to Jan-Christopher Horak, the director of UCLA's film and television archive, it is likely that other contracted MGM actors and actresses also lent their voices to the films, although none of that work was credited.
To a modern viewer, it can be hard to tell who the audience of these films were. It might seem like a canine cast is best suited for children, but the plots were often mature, featuring adultery, murder, and even cannibalism.
So how did these films come to be made? To understand that, one must also understand the way the studios were operating in the late 1920s and early 1930s. In this era, shorts would play before a full-length feature. They were primarily produced by independent companies and distributed through the studios. As the popularity of the shorts grew, studios brought on some of those independent producers to develop in-house work.
In 1929, according to film historian Rob King, MGM hired Jules White and Zion Myers to organize their new short subjects department. White had close connections in Hollywood. In King's recent book Hokum!, he writes that Jack White, the older brother of Jules, was a top comedic shorts producer who helped Jules secure work as an assistant film editor before being recruited by MGM. A young Myers began working at Universal as a secretary in the early 1920s, when his sister Carmel was a rising silent film star. One of his co-workers there was Irving G. Thalberg, who would go on to become a legendary figure in American filmmaking. When Thalberg became an executive at MGM in the 1920s, Myers was able to secure a job at the company as a shorts director.
The Dogville shorts started with 1929's College Hounds, a parody of Buster Keaton's College that features a huge doggie football game. The next film was Hot Dog, about a murder in a seedy cabaret after a jealous husband finds out his wife has been cheating on him. The subsequent films all had equally punny names. There was the murder-mystery Who Killed Rover? and a Broadway parody called The Dogway Melody. Those were followed by The Big Dog House, All's Canine on the Western Front, Love Tails of Morocco, Two Barks Brothers, and Trader Hound, a riff on MGM's Trader Horn.
The opening credits for the 1930 movie Who Killed Rover? IMDB
Some of the dogs came trained from renowned Hollywood animal trainer Rennie Renfro. Renfro had a ranch in Van Nuys where he reportedly trained roughly one hundred dogs for films over the course of his long career. Renfro worked closely with Myers and White to direct each short. Since they shot on silent film, the directors often shouted their commands to elicit the desired behavior from the dogs.
Other techniques were utilized as well, especially when it came to making the canine performers appear as if they were speaking. According to a January 1931 article in Popular Science Monthly, a director or Renfro himself would stand in front of a dog and wave various lures to focus the canine's attention. The human would then open his hand repeatedly to entice the dog to open its mouth. Another method to imitate speech involved giving the dogs toffee to make them chomp.
The same Popular Science Monthly mentions the directors' preference for stray and mixed-breed dogs "because they are not high strung and can get along better in groups than the animal 'prima donnas' of breeding." The directors also used "veteran" animal actors, as they were less likely to miss cues or run off set altogether. Rumors have long circulated that those veteran dogs, including Renfro's beloved Buster, received special treatment, including their own waiting areas, exercise tracks, and air conditioning, which was rare even for human actors at the time. But these claims cannot be verified.
A scene from Hot Dog, showing dogs dancing at the "Bow Wow Inn Dancing Revue." Warner Bros/YouTube
Although shorts were typically not reviewed, the Dogville Comedies appear to have been well-received based on trade papers of the time. According to Warner Bros., "a nationwide theatre owners poll in 1930 rated the Dogvilles as the best short subjects over more legendary comedy and musical series."
Even Jules White would later say that his favorite project of his entire career was "the dog things." "All the stars at MGM would come over and watch us film them," he said in a 1982 interview with The Los Angeles Times. He recalled that Greta Garbo liked to admire the cute dogs and was a frequent visitor to the set.
But not everyone was charmed by the "Barkies" and a backlash ensued. The dogs do not look comfortable as they walk on their hindlegs in stiff costumes, apparently held upright by piano wire. The Performing and Captive Animals' Defense League wrote to the British Board of Film Censors to protest the release of these shorts. Several films in the series were thus banned by the British censor citing animal cruelty.
A still from The Big Dog House, 1931. From Cinematograph Industry: Cruelty in Films, Trades Union Congress archive, Modern Records Centre, University of Warwick, UK (MSS.292/675.12/5)
All-animal casts were not entirely novel. Released between 1923 and 1924, Dippy-Doo-Dads were Hal Roach-directed silent films featuring monkeys as the stars. A smaller company called Tiffany created a series of chimp comedies in the early 1930s using the same template as the Barkies. They may have been the product of sibling rivalry, as they were actually produced by Jack White, brother of Jules.
The creators stopped making the Dogville Comedies in 1931 after the controversial Trader Hound, banned by U.K. censors for its hints at canine cannibalism. White and Myers were offered other jobs developing the shorts department at Columbia Pictures, where White went on to make film history with the Three Stooges. Myers continued directing and writing comedic shorts and films, even writing the scripts and creating stories for some of the Stooges productions that White directed, such as 1948's I'm a Monkey's Uncle.
Today, the Barkies find themselves relegated to a footnote in the history of early talking pictures. But for almost two years, man's best friend was also the silver screen's biggest star.
Mapping the Sounds of Political Protest Around the World
A new project is collecting recordings of public activism going back to 1991.
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The Milwaukee Dogs That Learned to Sniff Out New Zealand Mud Snails
In a Wisconsin basement, two Labradors learned to detect tiny aquatic hitchhikers.
Ashley Stimpson January 11, 2021
Found: The Rare Singing Dogs of New Guinea, In the Wild
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Archaeology Dogs Can Help Scholars Sniff Out the Past
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