Health24.com | Learn how to throw an elbow like a Muay Thai fighter

If you’ve ever watched Kickboxer (the movie where Jean Claude van Damme kicks a banana tree until it breaks under the sheer power of his shins), you witnessed some serious badassery. Despite the name of the movie, Kickboxer actually had nothing to do with kickboxing, well except that his brother was a kickboxer (we can argue semantics later).

The fighting style of the movie is called Muay Thai, one that is rich in history and a huge part of Mixed Martial Arts fighting. We chatted to Gary Barret, a former Muay Thai fighter and owner of True Muay Thai, to find out exactly how Muay Thai can make you a total badass.

Read more: This 43-year-old uses karate to stay in the best shape of his life and why you should do it too

Over the course of his teens and early 20s, Barret gained experiences in various fighting styles but he says that he always came back to Muay Thai. “Teaching people Muay Thai is a lot of fun as there’s way more to offer,” he says. In 2016, Barrett and his family moved to Thailand where he trained and fought. When he returned to South Africa, he opened his gym, where he continues to train anyone wanting to learn how to fight, from professional fighters to beginners who are looking to get fit.

Read more: Waking up with diabetes changed this man’s life

It’s definitely not kickboxing

One common misconception is that Muay Thai is just kickboxing, well no. “Kickboxing is a hybrid of Muay Thai. You’re not allowed to throw elbows in kickboxing and you’re not allowed to continuously knee,” explains the 42-year-old. Muay Thai is a stand-up striking sport that involves clinching. It’s known as the art of eight limbs as there are eight points of striking punches, kicks, knees and elbows.

The sport is one which has a rich history. Legend has it that in the 18th century, famous Thai fighter, Nai Khanom Tom, was captured by the Burmese. Having heard that Nai was a famed fighter, the Burmese king gave Nai the opportunity to fight for his and the other prisoners’ freedom.

After the ritual of Wai Khru, the traditional dance that is done before fighting, Nai beat the Burmese boxing champion via knock out. Not convinced by Nai’s efforts, the king sent in another nine fighters to face Nai. But Nai won each fight and the freedom that came with it.

In Thailand, 17 March is regarded as Nai Khanom Tom day or Muay Thai day. Mauy Thai is the national sport of Thailand, with kids as young as seven fighting as professionals.

Read more: Build quads of the gods with these 6 moves to killer legs

Eat clean

“As a fighter, your diet should be clean,” says Barret. Depending on what’s available during that season, you should be eating fresh and heathy food. “So you’d want to eat good fats like avos, oily fish, loads of protein, leafy green vegetables and good carbs like sweet potatoes,” he advises. You’d want to load up on carbs before and after fights with the amount of energy burned during training and fighting.

Train mean

In Thailand, training can be pretty hectic. “You’ll start with five to 10km run and then make your way to the gym where you’ll skip for about 10 minutes. Then you’ll do some pad work, sparring, bag work and some conditioning. And in the evening you’ll be back to do it again.”

Training can be pretty painful but in the end it makes you a stronger and better fighter. Take shin conditioning for example, in Muay Thai, the shins are used to block and make kicks. So your shins have to be able to withstand a bone to bone strike. Check out the video below to get a better idea of why conditioning is necessary.

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3 moves to help you win a fight

With great power comes great responsibility, so don’t go using these moves to show off. If you find yourself in a position where you need to defend yourself, these three moves could potentially save you.

Elbow

“Punching is effective but there’s a good chance that in a dangerous situation you could end up hurting yourself instead. An elbow to the head or jaw can be enough to knock someone out.” If you’re in close enough range, tuck your hand in at the chest, as you step in, throw your weight and pivot your hips when you strike.

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Knees

If you’re able to get your arms around the attacker’s neck, pull them down into your knee while striking your knee upwards. Be sure to aim for their ribs and stomach.

via GIPHY

Flat hand

Similar to a hook, just keep your hand open instead. Landing this hit on the ear, will send a pop or a shockwave into the head, disorientating the attacker.

via GIPHY

This article was originally published onwww.mh.co.za

Image credit: iStock 

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Health24.com | 9 common sex injuries – and how to deal with them

Sex is usually a pretty wonderful thing…until, that is, issues arise. There are those annoying situations, like being left sans orgasm (ugh). And then there are other times when sex can be downright hazardous.

Sex injuries happen more often than you might think – so you should be aware of the most common ones (mostly so you can figure out what to do if they happen to you…).

Don’t forget to take our sex survey – you could stand the chance of winning R5 000 in cash! 

1. Vaginal tears

You know it’s happened when you’re bleeding down there after the deed, or it simply really, really hurts.

The fix: The reason tearing happens is that you’re too dry down there, meaning the fix is pretty simple: Be sure you’re lubricated enough before he enters you. “This can mean going slower during sex, or simply using lubricant,” says Dr Debby Herbenick, research scientist at Indiana University and author of Sex Made Easy.

If you do all of this and you still experience tearing on the regular, see your gynae, who can prescribe certain antibiotics. If it’s just a one-time thing, wait it out. “Most vaginal tears are small and heal on their own,” says Dr Herbenick. “But if a cut is bigger or keeps bleeding, call a healthcare provider.”

Read more: 7 times your vagina hurts during sex – and what the pain means

2. Carpet burn

Go you for being adventurous and not just sticking to the mattress! Seriously, round of applause. However, switching up where you have sex can cause painful carpet burns due to friction (#BedroomBattleWounds).

The fix: Wash the infected area with cool water and antibacterial soap, advises Dr Jennifer Wider, a women’s health specialist. If the skin is actually broken – as in, there is a physical cut as opposed to just irritated redness – then clean it with antiseptic and apply antibacterial cream before putting a bandage on top.

Of course, the best advice is to go on pre-emptive strike and put a soft throw down if you’re having sex on a rough surface. Just be sure it’s one of your backup blankets, as things could get a little, well, you know.

couple cuddling on carpet

3. ‘Foreign objects’ in the vagina

I’m about to get graphic here, but the two most common “foreign objects” gynaes encounter are forgotten tampons (hey, it happens) and lost condoms. And yes, gynaes actually refer to them as “foreign objects”. Now you know.

The fix: Start by taking a deep breath and not freaking out; it happens and you can totally get that thing out. “The best course of action is to wait 10 or 15 minutes after you’ve had sex,” says Dr Herbenick.

That’s the time it takes for your vagina to get back to its normal, unaroused size – and it’s a lot easier to reach up there in its normal state than when it’s all engorged from sex.

Just relax, and insert two fingers to try to get it out. If you can’t, call your doctor ASAP and they can fish it out for you.

4. …or anus

While it’s pretty common for things to get lodged up in your vagina, it’s also possible for anal play to go south (er, north?). “While I was a general surgery resident, I encountered some ‘unique’ objects lodged in the rectum,” Dr Joshua D Zuckerman, a plastic surgeon in New York told Women’s Health US in a previous interview. “In one case, we had to surgically remove a pink softball from someone’s rectum and, in another case, a significantly-sized potato.”

The fix: While there’s no shame in sticking things up your butt during sex, it’s probably best to steer clear of things like softballs and food, which can easily get lost up there or cause infection.

Read more: 6 different butt plugs to introduce you to anal play

5. Back injury

Not to knock a good sex move, like reverse cowgirl or the butter churner, but sadly those “She did what?!” skills can also wreak havoc on your back.

The fix: Applaud yourself for being such a bedroom baller. Done? Okay, now time for damage control. “Put an ice pack on your lower back to relieve inflammation,” Dr Wider advises. “Then, once the inflammation subsides, use a heating pad to soothe your muscles.” Finally, pop an ibuprofen and rest for a couple hours.

6. Food irritation

Sure, it’s totally sexy to bring strawberries and whipped cream into the bedroom. And, in a pinch, foods like coconut oil even make for decent lube. But in most cases, food is not a sexy friend.

Dr Gabe Wilson, an emergency physician in Southeast Texas told the Women’s Health US team one such horror story, “One time, I treated a woman whose partner had performed cunnilingus on her immediately after eating some spicy food. The hot sauce her partner consumed prior to the sex act left mild burns on her genital region.”

The fix: If you find yourself in this unpleasant situation, try neutralising the burn (generally caused by a spice called capsaicin) with soap and water or fatty dairy products, such as whole milk or yoghurt (as weird as that may sound).

Otherwise, when in doubt, keep food far away from your vagina. And if either you or your partner have eaten or cooked with spicy foods (like hot sauce or peppers), you should probably avoid orally or manually stimulating each other right away.

chilli and powder

Read more: 6 things you should never ever do before you have sex

7. Urinary tract infection

Anyone who’s ever gotten one of these knows they’re a real pain. And sadly, you can get them from having lots of sex.

The fix: The best thing to do is to make sure you’re lubricated enough at all times, whether that’s by actually using lube, or just being sure that your partner doesn’t enter you too early or go too rough. That helps prevent tears or irritation, which make UTIs more likely.

And if you notice a burning sensation when you pee or have to go constantly (signs of a UTI), go see your doctor to confirm the diagnosis. They’ll get a prescription for antibiotics to beat the infection, ASAP.

8. Yeast infection

While sex does not cause yeast infections, they more commonly occur in women who are sexually active. Most women who get yeast infections from sex get them either from receiving oral sex or from having sex with a guy who has some saliva on his penis (i.e., after you’ve gone down on him), says Dr Herbenick.

The fix: “Start by making sure that his penis is clean when he enters you,” says Dr Herbenick. If this means having him go to the bathroom after foreplay, then so be it.

And if you do suspect you have a yeast infection, make an appointment with your doctor (it’s never a good idea to self-diagnose). They’ll likely give you a prescription for an anti-fungal medication to be taken intra-vaginally or orally.

If you get yeast infections more than four times a year, you may simply be more prone to getting them in general – so talk to your gynae about that, and she can decide the best course of action.

woman with itchy vagina

Read more: The 4 most dangerous sex positions for his penis

9. Broken penis

Okay, this doesn’t happen that often, but it’s worth noting – because, admit it, it’s the first thing that came to mind when you clicked on this article.

To set the record straight, you can’t literally break a penis, since it doesn’t contain bones. But you can severely bend a penis, to the point that the two tubes of blood that fill it during an erection actually rupture, urologist Dr David Kaufman, of New York’s Central Park Urology told Women’s Health in a previous interview. There’s usually a snapping sound when this happens, followed by severe pain, a bruised penis and swelling.

The fix: These injuries almost exclusively occur during super-rough sex, says Dr Kaufman. Of course, this doesn’t mean you should resort to vanilla sex the rest of your life. Instead, just be mindful – and, if this does occur, go to the emergency room ASAP.

“The best treatment is surgery to evacuate the blood clot and repair the ruptured corporal body,” says Dr Kaufman. And, whatever you do, do not put ice on it. Dr Kaufman says, “Treatment involving icing, compression, etc., runs a high risk of penile scaring and impotence.” Yeah, no thank you.

This article was originally published on www.womenshealthmag.com

Image credit: iStock 

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Health24.com | How much sushi is it safe to eat per week?

Whether you are a spicy tuna roll aficionado or simply can’t live without your weekly dose of a negi hamachi roll, there’s no denying it: Sushi is freaking amazing.

But while you would love to schedule a nightly date with a king crab roll for one and a platter of sashimi on the side if given the chance, you might be wondering exactly how much sushi is safe to eat on a regular basis.

To put your mind at ease, “Sushi, which is mostly made up of seaweed, rice, vegetables and fish is a healthy meal option,” says Barbie Boules, a registered dietitian in Illinois. (Phew.)

How freaked should I be about mercury, though?

Sure, mercury is a concern for most people when it comes to fish, says Claire Martin, co-founder of Being Healthfull. And rightfully so: Mercury poisoning can cause headaches, dizziness, developmental delays, brain damage and even organ failure.

But not all fish carry the same mercury risk. “The higher up on the food chain, the more likely there is mercury, which doesn’t leave the body once the fish ingests it,” she says. So larger fish that eat smaller fish – such as swordfish, tuna and mackerel – are all examples of fish that tend to have higher mercury levels, Martin says.

“You should moderate your consumption of these types of fish in sashimi, nigiri or otherwise,” Martin says. “I wouldn’t eat these fish more than twice a week.”

On the other hand, Martin says maki sushi – those rolls you love oh-so-much – are often made from fish that are much lower in mercury content… meaning you can safely eat it more often. This includes salmon, crab, shrimp and eel.

To balance out your nutrients (and lessen your mercury intake), Boules recommends building your sushi order by choosing one roll (five pieces) with a low-mercury raw fish like salmon, then loading up on veggie options or cooked shrimp and crab.

Read more: 4 things you should never order from the sushi menu

Great, so we’re all set here, right?

One catch for pregnant ladies: Eating raw fish should be avoided because of the risk of mercury poisoning and foodborne illnesses that could affect you and your little one. (Same goes if you’re currently breastfeeding.)

Boules says pregnant women and children should limit their consumption of fish to 226 grams per week, and steer clear of high mercury fish entirely.

The bottom line: “Overall fish consumption should be 340g per week for healthy adults, 170 to 226g per week for pregnant women and children,” Boules says. “Be mindful of choosing lower mercury options.”

This article was originally published on www.womenshealthmag.com

Image credit: iStock 

https://www.womenshealthmag.com/food/a22139515/sushi-mercury-levels/

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Health24.com | How Nicholas Dlamini made it to the cycling world stage

The twisty mountain passes of the Alps are ahead; a far cry from his home in Capricorn Park near Muizenberg, Cape Town. And yet, that is exactly where Nicholas Dlamini’s bicycle took him, when in June 2017 he won the King of the Mountains category at the under-23 Giro d’Italia – a first for an African.

If it’s his bike that got him there, it’s his passion, unwavering dedication and pro-class work ethic that is going to take him further. In August 2017, the 22-year-old took another huge pedal stroke toward that goal, when he made the step up from the Dimension Data Continental team (a feeder programme of sorts) to join the likes of Mark Cavendish, Daniel Teklehaimanot and Edvald Boasson Hagen on Team Dimension Data for Qhubeka’s World Tour outfit.

Dlamini was back in South Africa for Dimension Data’s annual training camp, and spent some time at home. The informal settlement of Capricorn Park is your typical big-city fringe community, struggling with the usual socio-economic problems: Drugs and crime, low education levels and alcohol abuse.

It was here, as a 12-year-old, that Dlamini first got into cycling – thanks to a friend, Vuyisa Mgolombane, who persuaded him to join a small cycling club. There he cultivated his love for riding a bike, and realised it could take him somewhere – not only in the physical sense, but emotionally and financially as well.

Training wheels

South African ultra-trail legend Ryan Sandes remembers that 12-year-old. “Nic came to one of the first JAG Foundation Trail Running Camps I hosted,” Sandes explains. “Straight away you could see this kid was talented. I mean, just a natural athlete; but also, so determined to succeed,” he says.

“I tried to convince him to become a trail runner, but he very politely told me that he wanted to ride the Tour de France.” That wasn’t the end of their relationship, however; and both Ryan and wife Vanessa have been an integral part of Nic’s journey ever since, acting in a mentorship role. As though they have a son who has succeeded, they couldn’t be prouder.

At 17, Dlamini met Sven Thiele. Thiele’s HotChillee company runs the Cape Rouleur, a five-day, 600km speciality event through the Western Cape. Dlamini shone in this non-traditional event, and it became a stepping stone to his first European race experiences, thanks to Thiele.

Of course, you don’t simply go to Europe and get results straight away. It’s notoriously difficult to “learn” how to be a pro bike rider. And you don’t just ride your way into a world tour cycling team on talent alone.

In fact, natural ability – especially in a sport like professional road cycling – is a very small part of the consummate athlete package. By all accounts, Dlamini is that full package, and that’s perhaps demonstrated best by how he finished his matric.

The World Cycling Centre Africa in Potchefstroom – whose graduates include Merhawi Kudus and Daniel Teklehaimanot – was the base for the next part of Dlamini’s journey.

While there he had to complete his schooling, through correspondence; which came with endless admin issues for him (and Vanessa, who helped him through that year). But he stuck it out, rolling with every challenge and getting his matric done.

Read more: How to survive the Cape Town Cycle Tour on no training

This stubborn determination to succeed also impressed Dimension Data team principal Doug Ryder, who in a press interview announcing Nic’s move to the pro tour team commented, “This team was built on a dream; and to see a young rider like Nicholas, who came from limited means and opportunities to succeed… Nic has big dreams, and has worked so hard to realise his dreams, focusing first on getting through school and then on his passion for riding his bike.”

“I’ve learnt that one has to dream big, and work hard for those dreams,” Dlamini says when asked about his secret to success. “And to have role models,” he adds, mentioning names like Sandes and long-time professional cyclist Ben Swift among others. “That worked for me; and if I could give the kids back in Capricorn Park one bit of advice, it would be that – look up to others, and work hard.”

However, Dlamini points out, it’s crucial for youngsters to balance their studies and sport. “Work harder than everyone else in both,” he says. His Capricorn Park upbringing groomed and drove him to become the athlete and person he is, and he’s never forgotten his roots. That background (and its potential traps) gave him the hunger and edge to go and achieve – and he has; and yet he’s managed to stay humble through it all.

“Where he’s come from and where he is now… it’s very easy to get ahead of yourself, and perhaps get a bit of an attitude; but he’s got none of that,” says Sandes.

“It’s been very cool to follow his progress, and see him succeed,” Sandes continues. “But I think perhaps most important is that he has stayed the same person I met at that JAG running camp all those years ago. He’s still as humble and unassuming as he was back then, but he’s also really grown as a person – it’s inspiring to see him now kind of looking after his mother and sister.”

Read  more: From poverty to winning bronze at the Commonwealth Games

“He sees the bigger picture, you know. He’s been saving up to build onto his family home and buy more property – and very few young sportsmen think like that.

“I think if he does ride in the Tour de France one day, it’ll be one of my proudest moments,” Sandes says. “Just to see someone I know who a decade ago had hardly ridden a bike and is now riding the biggest bike race in the world. That would be the ultimate.”

This article was originally published on www.mh.co.za

Image credit: Paolo Penni Martelli 

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Scottish government to double funding for breastfeeding

An extra £2m is to be given to health boards in Scotland to offer help to mums who want to breastfeed their babies for longer.

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Health24.com | 5 signs you could be suffering from an ‘adult’ eating disorder

They’re older. They’re wiser. They’ve survived adolescence. Yet more and more grown women are suffering from anorexia, bulimia and other dangerous – sometimes deadly – eating behaviours. Women’s Health reveals the alarmingly familiar risk factors…

Read more: “I suffered from an eating disorder you’ve never heard of before”

For decades, the eating disorder lexicon had two main entries: Anorexia and bulimia. But modern research reveals that these fall woefully short of encompassing the many facets of disordered eating.

In the early ‘90s, the American Psychiatric Association introduced a new diagnostic category: Eating disorders not otherwise specified (EDNOS). A catch-all label that includes dozens of sub-diagnoses, EDNOS applies to patients who don’t meet the exact criteria for anorexia or bulimia but still have very troubled relationships with food or distorted body images.

Today, EDNOS diagnoses significantly outnumber anorexia and bulimia cases. The atypical has become the typical. Here, just a few atypical eating disorders.

1. Orthorexia

A fixation with healthy or righteous eating. Orthorexics often eat only organic foods, eliminate entire food groups or refuse to eat anything that isn’t “pure” in quality. Unlike anorexics, they don’t necessarily think they’re fat or strive to be thin; some are motivated by a fear of bad health or a fixation with complete control. “This plays havoc with their self-esteem, as the person often berates herself,” explains dietician and author Tabitha Hume. Ironically, severe orthorexia can lead to malnourishment.

Read more: Orthorexia and me: What it’s like to have a “healthy” eating disorder

2. Pregorexia

Extreme dieting and exercising while pregnant to avoid gaining the 11 to 15kg of weight doctors usually recommend. “There’s more pressure on women to look thin during and after pregnancy,” says Hume. But pregorexia comes with serious health problems. Starving moms-to-be are at risk for depression, anaemia and hypertension, while their malnourished babies are often miscarried or born with birth defects.

“Mothers who over-restrict during pregnancy often deliver early, and the combination leads to a severe problem, where the child is born with a thrifty gene that sets them up for diet-resistant obesity, diabetes and heart disease from early adulthood onwards,” she says.

Read more: “I can’t stop eating sand – the truth about pica and soil addiction”

3. Binge eating

Compulsive overeating, often to deal with negative emotions or stress. Binge eaters consume large amounts of food very quickly – until they’re uncomfortably full. Most sufferers eat in secret to hide their habits. Many feel powerless to stop eating and are disgusted with themselves afterwards; but unlike with bulimia, they don’t attempt to reverse a binge by vomiting or fasting. While not all patients are overweight, obesity – and its related health problems – is obviously a risk.

Read more: “My life with a binge eating disorder”

4. Anorexia athletica

Addiction to exercise. Sufferers work out well beyond the requirements for good health, often to the point that their gym time interferes with their job or relationships. “Instead of throwing up, so-called compulsive exercisers purge kilojoules by working out religiously,” says Dr Sari Shepphird. “Often, if they don’t keep up with their rigorous routine, they feel tremendous anxiety or guilt.” They’re also at risk for potentially fatal cardiac problems and depression.

Read more: 5 signs you could be suffering from an exercise disorder

5. Drunkorexia

Restricting food intake in order to reserve those kilojoules for alcohol and binge drinking. A US study found that almost 30% of female varsity students exhibit drunkorexic behaviour, “saving” their kilojoules for booze in order to avoid gaining weight or to get drunk faster. Bad idea: These women are upping their chances for alcohol poisoning, uninhibited sexual behaviour and long-term consequences like heart and liver diseases.

This article was originally published onwww.womenshealthsa.co.za

Image credit: iStock 

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Health24.com | 1 000 parents described their sex lives post-baby, here’s what they had to say

You bought all the books, assembled the crib yourself and have your route to the hospital all mapped out. On paper, you seem pretty prepared, but in real life, having a baby can bring on challenges and changes that you’d never predict. Especially when it comes to you and your partner’s sex life.

As Men’s Health previously reported, your sex life is probably going to change after you have a baby. Your partner’s body will take time to recover, and she may not be turned on by the same things she was before. Also, you’ll both be tired as hell.

Read more: “I had a colonoscopy – this is what it’s really like”

To learn more about how people’s sex lives change after they become parents, Leesa, a mattress company, polled nearly 1 000 parents about their sex lives post-baby. Here are some of their findings.

How having a baby affects your sex life

While a few lucky souls said their sex lives improved after they had kids, 46% of respondents said the quality of intimacy with their partner got worse.

According to Leesa’s analysis, that negative change could be due to “numerous factors, including the fact that a new baby can wreak havoc on our beloved sleep schedules and also sever our free time for romance tragically short, both of which can keep anyone’s libido down.”

Read more: Yes, dads can suffer from paternal postpartum depression, here’s all you need to know

The survey also found that 61% of women wanted less sex after the birth of a child, compared to just 30% of men. One reason, according to the study, could be that “women are wired to develop a strong bond with their kids, which comes by way of the ‘love’ hormone oxytocin, and taking care of a small child can satisfy a woman’s need for attachment and closeness.”

Expanding your definition of sex

Since vaginal intercourse may be out of the question, plenty of new parents are expanding their definition of sex. The survey found that couples were far more likely to engage in manual stimulation, give and receive oral sex, and have quality cuddling sessions after kids.

Making time for sex after a baby

With a tiny, screaming human to take care of, it can be tough to find time for romance. On average, parents experienced a 47% decrease in the frequency with which they had sex.

So when are they finding time to get it on? According to the study, 67% of parents wait until their child is asleep for intimate time; 47% sneak into the shower for a little steamy action; and 26% are willing to throw down cash for a kid-free vacation.

Read more: The workout you can do with your kids – and how to raise a fitter family

Meanwhile, some couples go months – even a year – without sex after kids. It’s normal.

“If you feel like you’re getting side-lined, bring it up [with your partner],” Chris Murdock, an advisory board member of the support and social group Dads Married to Doctors, previously told Men’s Health. “But if you’re upset that you don’t have her attention the same way you used to, and if you want things to stay the same… they won’t.”

To read more about Leesa’s study on new parents’ sex lives, click here.

This article was originally published on www.mh.co.za

Image credit: iStock 

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Engineers use Tiki torches in study of soot, diesel filters

Chemical engineers testing methods to improve efficiency of diesel engines while maintaining performance are getting help from a summer staple: Tiki torches.

A team of engineers at the University of Notre Dame is using the backyard torches as part of an effort to mimic the soot oxidation process in a diesel engine — when soot in diesel exhaust collects in the walls of a particulate filter and has to be burned off — according to a study recently published in Catalysts.

“This study is part of an effort over many years in which we have discovered and developed low-cost catalysts for soot oxidation that are based on silica glass,” said Paul McGinn, a co-lead author of the study and professor in the Department of Chemical and Biomolecular Engineering at Notre Dame.

McGinn and co-principal investigator Changsheng Su at Cummins Inc. developed a method to coat diesel particulate filters with a silica glass, which slowly releases potassium ions. The potassium acts as a catalyst, reducing temperatures required to initiate filter regeneration — or soot oxidation — for improved efficiency.

What they needed was a simple way to simulate real-world driving conditions, including the continuous flow of soot as it passes through a diesel particulate filter.

“We could do it continuously using the Tiki torch, using the Tiki soot as a surrogate for real engine soot,” McGinn said. “Depending on the setting, you really get a lot of soot coming off of it, which is what we want.” The team constructed a sophisticated reactor equipped with soot generator and backpressure sensors, which allows them to control conditions including oxygen rates, air-to-fuel ratios and soot production per hour.

New methods of reducing soot oxidation are of particular interest to manufacturers of diesel engines. Diesel exhaust contains, among other things, soot particles and nitrogen oxides (NOx), with soot being a major contributor to global warming and a cause of breathing problems. The Environmental Protection Agency (EPA) has been working to reduce emissions from vehicles, industrial vehicles, locomotives and ships for more than a decade.

For diesel engine vehicles, the EPA requires both soot and NOx be kept below certain levels but challenges remain to reducing those emissions economically without sacrificing performance. When the engine’s operating conditions are adjusted to emit low levels of NOx, soot levels increase, and vice versa.

A standard diesel particulate filter is a ceramic cylinder with a honeycomb-style structure and porous walls. Every other channel — or opening — of the filter is closed off. As exhaust enters the filter, soot collects along the interior walls as cleaned exhaust passes through.

To burn off soot buildup along the filter walls, exhaust temperatures need to reach 600 degrees Celsius (1,112 F). “When you’re in an urban environment where you’re stopping and starting your engine, the exhaust temperature doesn’t get that hot,” McGinn said.

In some cases, fuel is used to heat up the filter and burn off the soot — a process called active regeneration — which delivers a hit the vehicle’s fuel mileage and requires substantial noble metal (such as platinum) usage.

“Everyone is looking for a low-cost way to get the temperature down,” McGinn said. “In our case, we’ve developed an inexpensive glass coating that’s one to two microns thick and apply it to the diesel particulate filters. The glass delivers a potassium catalyst slowly over 150,000 miles of driving and allows for what’s called passive regeneration. So when you’re out on the highway at high speed, the exhaust temperature gets high enough to burn off soot buildup continuously.”

With Tiki torches providing the soot buildup needed for testing, McGinn said his team will look at how to further tailor the glass composition to also reduce NOx.

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Optical neural network demo

Researchers at the National Institute of Standards and Technology (NIST) have made a silicon chip that distributes optical signals precisely across a miniature brain-like grid, showcasing a potential new design for neural networks.

The human brain has billions of neurons (nerve cells), each with thousands of connections to other neurons. Many computing research projects aim to emulate the brain by creating circuits of artificial neural networks. But conventional electronics, including the electrical wiring of semiconductor circuits, often impedes the extremely complex routing required for useful neural networks.

The NIST team proposes to use light instead of electricity as a signaling medium. Neural networks already have demonstrated remarkable power in solving complex problems, including rapid pattern recognition and data analysis. The use of light would eliminate interference due to electrical charge and the signals would travel faster and farther.

“Light’s advantages could improve the performance of neural nets for scientific data analysis such as searches for Earth-like planets and quantum information science, and accelerate the development of highly intuitive control systems for autonomous vehicles,” NIST physicist Jeff Chiles said.

A conventional computer processes information through algorithms, or human-coded rules. By contrast, a neural network relies on a network of connections among processing elements, or neurons, which can be trained to recognize certain patterns of stimuli. A neural or neuromorphic computer would consist of a large, complex system of neural networks.

Described in a new paper, the NIST chip overcomes a major challenge to the use of light signals by vertically stacking two layers of photonic waveguides — structures that confine light into narrow lines for routing optical signals, much as wires route electrical signals. This three-dimensional (3D) design enables complex routing schemes, which are necessary to mimic neural systems. Furthermore, this design can easily be extended to incorporate additional waveguiding layers when needed for more complex networks.

The stacked waveguides form a three-dimensional grid with 10 inputs or “upstream” neurons each connecting to 10 outputs or “downstream” neurons, for a total of 100 receivers. Fabricated on a silicon wafer, the waveguides are made of silicon nitride and are each 800 nanometers (nm) wide and 400 nm thick. Researchers created software to automatically generate signal routing, with adjustable levels of connectivity between the neurons.

Laser light was directed into the chip through an optical fiber. The goal was to route each input to every output group, following a selected distribution pattern for light intensity or power. Power levels represent the pattern and degree of connectivity in the circuit. The authors demonstrated two schemes for controlling output intensity: uniform (each output receives the same power) and a “bell curve” distribution (in which middle neurons receive the most power, while peripheral neurons receive less).

To evaluate the results, researchers made images of the output signals. All signals were focused through a microscope lens onto a semiconductor sensor and processed into image frames. This method allows many devices to be analyzed at the same time with high precision. The output was highly uniform, with low error rates, confirming precise power distribution.

“We’ve really done two things here,” Chiles said. “We’ve begun to use the third dimension to enable more optical connectivity, and we’ve developed a new measurement technique to rapidly characterize many devices in a photonic system. Both advances are crucial as we begin to scale up to massive optoelectronic neural systems.”

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New geometric shape used by nature to pack cells efficiently

As an embryo develops, tissues bend into complex three-dimensional shapes that lead to organs. Epithelial cells are the building blocks of this process forming, for example, the outer layer of skin. They also line the blood vessels and organs of all animals.

These cells pack together tightly. To accommodate the curving that occurs during embryonic development, it has been assumed that epithelial cells adopt either columnar or bottle-like shapes.

However, a group of scientists dug deeper into this phenomenon and discovered a new geometric shape in the process.

They uncovered that, during tissue bending, epithelial cells adopt a previously undescribed shape that enables the cells to minimize energy use and maximize packing stability. The team’s results will be published in Nature Communications in a paper called “Scutoids are a geometrical solution to three-dimensional packing of epithelia.”

The study is the result of a United States-European Union collaboration between the teams of Luis M. Escudero (Seville University, Spain) and that of Javier Buceta (Lehigh University, USA). Pedro Gomez-Galvez and Pablo Vicente-Munuera are the first authors of this work that also includes scientists from the Andalucian Center of Developmental Biology, and the Severo Ochoa Center of Molecular Biology, among others.

Buceta and colleagues first made the discovery through computational modeling that utilized Voronoi diagramming, a tool used in a number of fields to understand geometrical organization.

“During the modeling process, the results we saw were weird,” says Buceta. “Our model predicted that as the curvature of the tissue increases, columns and bottle-shapes were not the only shapes that cells may developed. To our surprise the additional shape didn’t even have a name in math! One does not normally have the opportunity to name a new shape.”

The group has named the new shape the “scutoid,” for its resemblance to the scutellum — the posterior part of an insect thorax or midsection.

To verify the model’s predictions, the group investigated the three-dimensional packing of different tissues in different animals . The experimental data confirmed that epithelial cells adopted shapes and three-dimensional packing motifs similar to the ones predicted by the computational model.

Using biophysical approaches, the team argues that the scutoids stabilize the three-dimensional packing and make it energetically efficient. As Buceta puts it: “We have unlocked nature’s solution to achieving efficient epithelial bending.”

Their findings could pave the way to understanding the three-dimensional organization of epithelial organs and lead to advancements in tissue engineering.

“In addition to this fundamental aspect of morphogenesis,” they write, “the ability to engineer tissues and organs in the future critically relies on the ability to understand, and then control, the 3D organization of cells.”

Adds Buceta: “For example, if you are looking to grow artificial organs, this discovery could help you build a scaffold to encourage this kind of cell packing, accurately mimicking nature’s way to efficiently develop tissues.”

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Materials provided by Lehigh University. Note: Content may be edited for style and length.

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