Supply. What else is stop is a recently resurfaced concert venue a grateful kestrel sound isnt just down to skilled musicians acoustic technicians also play a major role. Youd think theyd check the acoustics by getting a musician to play an instrument think again. Shots fired in dresden score two apologist a woman has loaded a gun going on stage and is firing at into the air. While a man stands by listening attentively. Common and Maglite Lautenbacher are acoustic technicians in the last few years the call to a palace has undergone major renovations and the two were part of the project from
the outset no theyre testing to see if the acoustics are as good as they had hoped obviously they need an audience in its place they use specially made lengths of fabric a full concert hall sounds very different than an empty one. Firing the gun allows them to measure reverberation. But why dont they just use an instrument. There are several ways of Measuring Reverberations whats important is to make a noise that can be easily reproduced the exact sound made by a Musical Instrument cant always be reproduced to report the sound a gunshot makes can be consequence and it covers the full range of frequencies and has sufficient energy especially in the lower frequencies so the volume and so on pattern of a fired hand gun is always the same. At strategic spots in the concert hall the acoustic technicians measure how long it takes for the sound of the gunshot to die
what exactly is an Impulse Response heres a floorplan of the stage circle installs the sound made on the stage is the impulse. It reaches the audience from the stage both via a direct route. And also by reflecting off the walls. This is the rooms response to the impulse and it needs to be uniform everywhere in the room. The hall is structured like a vineyard to ensure a consistent Impulse Response testing every single Sound Frequency would be too time consuming so the acoustic technicians bundle them into what are known as one third octave bands they sound like this. A deafening roar but theres a trick to it to understand what heres a crash course in sound and acoustics. Sound is
a wave like vibration whether a sound as high or low depends on the frequency of the Vibration Frequency is measured in hertz one hertz equals one vibration percent and humans can hear a sound in the range between sixteen and Twenty Thousand hertz anything below sixteen hearts we call infrasound anything above Twenty Thousand hertz is all to a sound music is usually between fifty and Eighteen Thousand hertz its impossible to individually measure the Impulse Response of so many sounds or frequencies thats why acoustic technicians divide them into sets encompassing eight notes. Lets take this low c. For example as a starting point it has a frequency of One Hundred Thirty hertz. An Octave Higher is middle c. Its frequency is exactly double that of the low c. Two hundred sixty hertz after the same interval you come to the next c. Which has a frequency of Five Hundred Twenty hertz and so on the frequency doubles with every
octave. The sound waves frequency can be divided into sets with the help of an octave eight notes into what are called octave bands. Then divide these into a further three sets one third octave bands the signal emitted contains the full range of a one third octave band as soon as the war dies out the technicians check to see if the full range of frequencies are being reflected equally by the room to hear their actual then we have the direct sound thats the easiest and fastest route from the source to the microphone we can see a vast amount of reflection from the. Ceilings and combinations of all these responses reaching the ears. That since around music. Thats the sweet spot the technicians measure it in every corner of the room the acoustics are perfect. Let the music began. Nature can put an impressive concerts as well. For move on that she growls and songs produced by artists from the animal world just head for d w dot com slash noisy animals and of course were also on twitter and facebook. Sounds can be closely tied to remembering do you have a memory that will stay with you for the rest of your life we asked you that on facebook heres some of your responses. Septa and rio remembers the first day of kindergarten he says it was the first time he recognized the importance of names and identities. Cara and he remembers a much saturday the day her father passed away. Never
forget celebrating with his. Only after graduation. And fog they go on her show the first glimpse of a soulmate was an unforgettable experience. Thanks for those comments keep them coming. Why are we more likely to remember scents and sounds and facts and figures it seems that the more emotional an experience is the more likely it is to end up in our long term memory. The first kiss with their first love. And aaron peter will remember this moment for their entire lives but why. Do you make that plays a central role in deciding the importance of our experiences the momentous and
emotional way all the morning or chemicals the region releases in the brain things like sour tone and joking me and norepinephrine and the higher the release the stronger the memory of an event. Such as an hour in p. T. His first trip together to africa where they had a close call with the lion the. Dramatic experiences like this send signals directly from the a mic dela to the hippocampus which appears to act as a kind of gatekeeper for long time memory it also decides what ends up in short term memory like your last order in a restaurant long time memories include things like your first major fight and other critical experiences. Nerve cells in the brain still memories when stimulated these neurons fire off chemical neurotransmitters to neighboring brain cells stronger stimuli activate small cell connections memories can never be
viewed as networks of large numbers of nerve cells spread throughout the brain and the active remembering is all about activating one of these networks and for instance such as the cologne worn by a rival ceuta can be enough to trigger a vivid memories. Of. The network of whats called perceived your own memory still sequences of movements has become almost automatic this is what allows anna to drive a car without having to think about it and lets peter play the piano for his sweetheart off to give practice. The left side of the cerebral cortex. Stalls general knowledge including speech. Even though peter hails from england he can communicate easily with anna who learned english in school. Whats called Perceptual Memory is located in the
cerebral it helps you recognize patterns. Allowing anna to identify an apple as an apple. And letting peter pick and his face out of the crown. The more you exercise your brain the bettin you can recall memories. Thats why peter has dedicated himself to rehearsing this song with his singing group. Together. But what really sticks in the memory of powerful emotional moments because peter tries so hard to please her and i remembers every new dish hes ever cooked. The birth of their first baby is another experience peter and i will no doubt always remember but what if they never have children studies show that sperm counts are falling dramatically among men in the Western World its an alarming trend with potentially catastrophic consequences. Are humans a threatened species. For now our cities are densely populated but the western industrialized world is witnessing an alarming trend male fertility is in decline. Guy levine is an epidemiologist who works at the Hebrew University of jerusalem and the dasa Medical Center hes evaluated one hundred Eighty International studies on sperm counts thats going to be really dug them up to were seeing a dramatic fall in the total sperm count and the Sperm Concentration and men in the Western World. The studies which levine evaluated work. Compiled over the last four decades between One Thousand Nine Hundred Seventy Three and Two Thousand And Eleven they examine the sperm count of healthy men in europe and the us a senior position at the Hebrew Universitys school of Public Health he says the
decline in male fertility is alarming yet sperm counts have fallen fifty percent in forty years. A human issue these days there are many men and israel germany austria the us denmark most western countries but not only in the west who suffer from fertility problems today you will. Roni coke men is a gynecologist and fertility expert at the party clinic of the dawson Medical Center she spent fifteen years researching the concentration and motility of sperm provided by israeli donors. Her Research Shows a forty percent drop in sperm quality. The quality of donated sperm needs to be excellent but if this trend continues by the year twenty thirty it will have declined to such an extent that i dont know is
will be in fact sile salami a profoundly worrying development. We. All know. That we must identify the causes and stop this. The israeli environment and health fund is hosting a conference in jerusalem. Everyone here is permille year with the results of the guy libyans research. The. U. S. Microbiologist Linda Barron Bomb is director of the National Institute of Environmental Health sciences in the u. S. State of North Carolina shes convinced that the decline in male fertility is caused by environment. Factors there is growing evidence that some of that its that there are many chemicals in our environment which did not used to exist which do a fact are in Decline Systems and many of them are affecting male reproduction he told
her colleague guy levine agrees with her findings. Are still hold were familiar with a few of these components but not with others and one thing became clear at this conference we cant afford to wait until we have an entire next generation suffering Health Issues or even worse that no next generation is no orne because of declining fertility. But what exactly are these chemicals in the environment which appear to have drastically reduced sperm counts within just two generations. No one including fertility expert roni cockman has so far found an answer but as an expert on diseases caused by environmental factors she has a few working hypotheses she suspects chemical such as valid used in plastics and other products could be to blame. So these Synthetic Materials plastics interfere with our Chemical Balance by acting like easter gentle and he engines
easter jen is the primary female Sex Hormone Androgen is the male home when im in the sea a little didnt want to be the gov we had the table this wall the telephone its all made of plastic plus this. When men come into contact with this stuff on a daily basis then it will have a chronic effect and its possible that it has an effect on the quality of sperm. And then theres the matter of nutrition we dont even know what all the fruits and vegetables we consume have been treated with. In fact the presence of contaminants in food has been demonstrated six workers with the Dole Food Company claimed they were left sterile after coming into contact with the pesticide b. C. P. Used on a Banana Plantation in nicaragua in the one Nine Hundred Seventy s. They went to court and last year were awarded some three Million Dollars in damages the case was the first of several lawsuits involving our Cultural Workers levines
research also shows that food treated with pesticides has an effect on the people who eat it. The point of pesticides by definition is to prevent reproduction so its no wonder that our research in the us shows theres no adverse effect on the sperm of men who consume fruit and vegetables that have been traded. On the moon. That for now the birth rate in israel remains robust. Even so researchers warn against complacency. That it might go alongside our research we need to protect the public from these chemicals chemicals we know are hazardous and should be banned and the manufacturers should be held accountable and there. Is time running out for humankind while the researchers in jerusalem continue to explore the causes of the cloning sperm counts theyre also pushing for Legislation Prohibiting Industrial Use of chemicals the best aside d. C. P. Is now banned researchers say its time others words to. Even studies on Stem Counseling conducted in asia africa and South America but they appear to show that male Fertility Death is fairly stable. Mates and makes people and animals better when theyre sick right not always. Overused and misused in health care and husbandry. This is led to the emergence of multi resistant bacteria. And if pathogens that i mean to therapy end up and water Distribution Systems it would be a major cause of concern. Like other microbes antibiotic resistant bacteria are invisible that means they can easily pass unnoticed but can they survive in our Water Systems could they be found in tap
water to answer that question were going to take a trip into the depths. And talked to experts who know all about this mysterious world among them chemists health geographers a microbiologist they all work for a German Research group known as who are and theyre interested in answering the same questions as we are. Where are their antibiotic resistant bacteria and pathogens. And concentrations of these bacteria in our waterways and sewer Systems Office and poor. Lets begin with sewage that means a visit to a Wastewater Treatment plant. Facilities like this receive wastewater from both hospitals and private households so waste created by both sick and healthy
people the sewage stinks and its pretty disgusting but apart from tampons and fecal matter does the sludge also contain antibiotic resistant bacteria from the looks of things it wouldnt be much of a surprise. First the sewage is run through clarify is which removes solid waste. These days its standard for the sewage to go through three stages of treatment after that the water certainly looks cleaner but its important to remember that any bacteria would remain invisible anyway the scientists take their samples back to the laboratory. Here they test not for the bacteria directly but for its d. N. A. Or more specifically Resistance Genes. Each dot in the data cloud represents a Resistance Gene the image on the left is before treatment the one on the right after so there are still antibiotic resistant bacteria in the water. We dont yet
know exactly how these bacteria behave in an outdoor environment but they do represent a potential risk to people if they come into contact with these germs and get infected. Treated water is channeled into rivers and streams along with its bacteria so the microbes are released into the environment the water from the treatment works mixes with that in waterways and is diluted so what does that mean for the bacteria time to meet up with another teen from the who recover Research Group they regularly check germanys rivers and lakes here to they find resistant bacteria and theres a further source of risk when you are. Many farm animals are also given antibiotics and excrete bacteria this is later spread on the fields as fertilizer where it seeps into the ground. Earth and rock act like
a natural filter for the water but do they trap all the resistant bacteria in the manure once again the scientists take samples. The further downstream they go the more residual waste they find from animals and people and thats reflected in their results. So you have a higher percentage of bacteria that are resistant to three four or more antibiotics and. A. Few people in germany who drink water directly from a river but what happens to the water next first passes through dense natural substrate filters in the ground or river bank. After that its directed on to the water works where its once again filtered unchecked the water then flows into homes across the country having come full circle. Although the water doesnt go through a Sterilization Process the scientists have yet to find any pathogens in german Drinking Water that are resistant to antibiotics. Our rivers and lakes are certainly polluted with this bacteria but our Purification Process for Drinking Water is good and that largely protects us. So Drinking Water in germany is not contaminated with antibiotic resistant bacteria at least for now. The most is psycho depends on sun and rain the Sunshine Water Evaporates Clouds Form Rain Fools and the earths bodies of water and replenished the into action of sun and rain also results in one of natures loveliest phenomena every year from india wanted to know more about rain. From surat gar wants to know. Why do rainbows appear as an ark. Rainbows form when the Sun Is Shining and light reflects refracts and disperses and Water Droplets in the sky. Water is denser than air like glass it redirects light and splits it into different frequencies raindrops act like miniature prisms all Refracting Sunlight Light bouncing off raindrops therefore creates the rainbow one person sees but someone else will see different rays so in a way everyone perceives their own personal rainbow. Double rainbows are formed by a further reflection of sunlight inside raindrops but the colors of the secondary rainbow appear to be reversed and also fainter thats because the extra reflection scatters many more of the raise. Rainbows are actually full circles but appear as
are expected as from the ground only their upper half is visible. Another example of the phenomenon is whats called a fog because of the small size of the Water Droplets that cause fog fog those have very weak colors one can even appear white so theyre sometimes called white rainbows. Then there are upside down rainbows these result from an optical phenomenon called Circumstance Arc which arises from the refraction of sunlight through ice crystals rather than raindrops. And if youre very lucky one day you might catch a glimpse of a full circle rainbow from an airplane or the top of a mountain anywhere where the view isnt blocked by the horizon. If you have a science question go to our website and send it in if we answer it on the show you
get our d. V. D. Featuring a Lighthearted Look at albert einsteins most famous theories. The most important thing is to never stop asking questions. On our next show well head to greenland with the ice is disappearing leaving behind huge amounts of photons sludge a Research Project is looking for ways to profit from it so thats next week on tomorrow today see you then. Cut cut cut cut cut. Cut. Cut. Cut. Cut. The other codons a significant cuts to the environment the new trend which proves Islam Susanto us in chile a major producer of the boom has had devastating results the reason running its uses lost amounts of water and im not has human and environmental costs of
a card in. The movie shows up in fifteen minutes on t. W. The fast pace of life in the digital globe shift as the lowdown on the web showing new developments and providing useful information on the witness finds and interviews with the makers and users. Should in forty five minutes on the. Philosopher and flip start a new mortgage and despised law karl marx maicon of communism a man whose ideas change the world but also divided it how willing to is he today and what influence does he have on politics and general culture has moved on the two Hundredth Anniversary of the birth of the Documentary Marx and his heirs come. D. W. The Dangerous Battle For Images Five women. Five
exceptional stories. One calling more photography dramatic pictures from The Frontlines Capturing Faithful Moments In Time and even risking death. She gave her life to other stories of people who ended up killing. Women bore photographers starting may third on g. W. How the germans came together in one nation from shove their money into chancellor although from bismarck. The history of the germans has been shaped by great movers. I swell always to bring my loyal followers the best to protect christendom and spread and find truth. And he is my. Colleagues of course i could be kind of the enemy. And stand by courageous
decisions that i was chose your master we have perceived problems are room for not for this presumptuous servant of the romans because. We must treat. The german starting in may thirteenth calling to w. Only. Israeli Prime MinisterBinyamin Netanyahu has claimed that iran lied to by to its Nuclear Weapons program he says israel has proof that around is still developing it despite the country signing an accord with world powers to stop doing so iran has dismissed the allegations. U. S. President donald trump has to spend a decision on imposing mental status on the European Union canada and mexico until