Author: BBC World Service

It’s frustrating to be stuck in traffic. Listener Collins from Nairobi, Kenya, spends at least three hours a day in traffic and he counts himself lucky. Many of his friends will easily spend six hours in traffic jams to get back and forth from work. Collins wants to know whether there is hope for his hometown – has any city managed to eliminate the worst of the traffic hot spots and how did they do it? Collins is not alone in his frustration. CrowdScience finds that congestion plays a major factor in the happiness and health of urban citizens. Commuters have been measured to have stress levels equivalent to that of riot police facing angry protesters.

So should our cities cater less for cars and what are the alternatives? Presenter Gareth Barlow heads to Copenhagen to meet the politicians and urban designers who have transformed the Danish capital from a city for cars to one for bikes and people. Presenter: Gareth Barlow. Produced by Louisa Field

(Photo: Afternoon traffic along Likoni road in Nairobi's Kilimani susburb. Credit: Getty Images)

As Europe experiences another record breaking heatwave, we look at the science of attribution. Usually it’s a long time after extreme weather events that scientists gather enough data to make a judgement on the influence of anthropogenic forces, such as man-made climate change.

However climate experts at a meeting Toulouse France, experiencing the worst of the heatwave, are crunching the data right now, to see if they can quantify the influence of climate change on this heatwave as it happens.

Also we find lakes of fresh water hidden – under the sea, find that Neanderthals went west and discover how spiralling laser light may be used to control a new generation of microelectronics.

(Photo: Heatwave in Paris. Credit: European Photopress Agency)

Presenter: Roland Pease Producer: Julian Siddle

Breathing is automatic: awake or asleep, running or resting, our bodies unconsciously make sure we get enough oxygen to function. But - unlike other bodily functions such as heart rate and digestion - it’s not hard to control our breathing consciously. If you’ve ever been to an exercise, meditation or yoga class, you’re probably familiar with instructions about how and when to breathe.

It was one of these instructions - “breathe in through your nose and out through your mouth” - that prompted CrowdScience listener Judi to wonder if this really was the best way to breathe during her exercise class. Is there good evidence to support the benefits of different breathing techniques - whether through the nose or mouth, fast or slow, noisy or quiet? And is consciously controlling your breath more about improving psychological focus, or optimising body mechanics?

Sports scientist Mitch Lomax takes us through the biology, chemistry and physics of breathing, and shows us how to train our respiratory muscles. We meet yoga guru Hansa Yogendra in India, where the study of pranayama - literally “breath control” in Sanskrit - is thousands of years old; and find out what scientists have discovered about the effects of these ancient techniques on the body and mind.

Presenter: Anand Jagatia. Producer: Cathy Edwards

(Photo: A woman jogging outside, wearing sports clothes on a blue sky background. Credit: Getty Images)

Iran’s nuclear programme is at the centre of a political row, with the country suggesting it could increase uranium production to above the levels permitted under an international agreement. We look beyond the rhetoric, discuss Iran’s covert history of nuclear development and ask scientifically what this latest move involves.

Fish are no respecter of international borders and when it comes to spawning, research reveals up to $10bn worth of potential fish stocks move between different political territories.

Ancient trees in the Eastern US are yielding clues to the climate going back more than 2000 years, they reveal there has been more rain recently.

And we look at how to quantify that rain as it falls now, over much shorter timescales.

(Photo:President Hassan Rouhani and the head of Iran nuclear technology organization Ali Akbar Salehi inspecting nuclear technology. Copyright: Office of Islamic Republic President via EPA)

Presenter:Roland Pease Producer: Julian Siddle

For decades, people suffering from chronic depression have relied on medicines that affect the levels of chemicals in the brain like serotonin, which regulate mood and emotion. But ten percent of people don’t benefit from any of the existing treatments for this devastating condition.

Sisters Annie and Kathryn have both been diagnosed with long-term depression that makes it hard for them to experience pleasure as others do. But they’re interested in whether there are new solutions on the horizon that could improve their wellbeing, in particular ones that don’t necessarily involve conventional medication.

Datshiane Navanayagam learns how a technique called mindfulness could strengthen neural connections in bits of the brain that communicate with each other. This, it’s said, may harness the ability of the brain to adapt and self-repair which can change people’s emotional responses to life’s ups and downs. She meets a psychologist who shows how this simple technique could improve our overall ability to process information and reverse negative thought patterns.

CrowdScience also hears about cutting edge research into the use of psychedelics as potential treatment for depression and heads to the UK’s only centre for ketamine therapy, where patients say a drug once popular with partygoers, is having a profound effect on their mental health.

Produced by Marijke Peters for BBC World Service.

(Photo: A woman sitting on the top of a mountain and meditating. Credit: Getty Images)

South Asia has experienced a heatwave where the monsoon has been delayed and temperatures have reached over 50 degrees. Despite this the extreme heat has led to far fewer fatalities than previous heatwaves; we look at why that is.

Research into the origins of almonds shows they were domesticated in Asia before spreading worldwide. It’s a bitter sweet story, with sweet varieties being selected over bitter ones. In fact the bitter ones contain poisons which can kill..

As with almonds cannabis as a drug seems to have spread via silk routes. The discovery of ancient burnt wooded bowls suggests it was smoked millennia ago in China – as part of funeral rituals.

And we investigate California’s cannabis farming industry, there are concerns over the environmental impact of this now legal cash crop.

(Photo: Indian boatman walks amid boats on the dried bed of a lake at Nalsarovar Bird Sanctuary. Credit: Sam Panthaky/AFP/Getty Images)

Presenter: Roland Pease Producer: Julian Siddle