their mothers were turning to living in the occupied drying land their father's soldiers from the french colonies. in a climate of national pride and racism. this documentary examines the few traces that remain of their existence. the choke chain . stores january 11th d.w. . how do you believe know which blossom to land on for the best nectar scientists studying flower to insect communication have an electrifying answer. animal testing is very controversial how viable are the alternatives. researchers are using a fresh method to study organ tissue in

a new light. welcome to tomorrow today our. medical professionals have various ways of looking inside the bodies of their patients an x. ray machine passes radiation through the body to capture an image on film. ultrasound on the other hand works with sound waves. and magnetic resonance imaging or m.r.i. uses magnetic field. but now there's a new method that allows doctors to see right through all of. this mouse can help researchers analyze all kinds of bodily functions from hell blood vessels and nerve tracks run to how internal organs are constructed. it's possible because the mouse is. tissue has been made transparent up to now this

hadn't been possible with human tissue. but now chemist john from the millions university in munich has uncovered chemicals that can render a kidney transparent within 2 weeks. she works with genetic engineer. the team wants to understand how human organs work specifically how blood vessels nerve cells and live channels interact making them visible is the 1st step. we have to understand how they're coordinating. in normal how to case and dan if you could easily also see when something is wrong when there is lack of coordination if there are some subtle supposed to be there are not there we can nor know why some diseases are cured. his aim is to determine the exact location of each individual cell to do this researchers have developed

a microscope that can examine the whole organ the different colors of the laser make the individual structures such as vessels or nerve cells visible. then we got a microscope scan some days of scanning it's millions of imaging data out there is no way hooman being cannot know life instead computer scientists have developed algorithms which enable an exact 3 dimensional image of the kidney to be generated from the data researchers can then study the organ cell by cell enabling them to recognize pathological changes detect cancer cells and observe the effects of medication to see if the drug in question is actually binding to the right cell the effects of the method could be far reaching my vision is that we will be able to generate organs on demand if someone needs a heart or kidney we will just take some stars maybe skin cells generate millions and billions of cells from and the same person and create a. construct the organ and then transplant to the person. first attempts to produce

parts of a kidney are already underway but it will take some time before the researchers are able to produce an entire order. in 2018 german laboratories tested drugs and cosmetics on nearly 1800000 rodents ac one thighs and rabbits and nearly 30000 farm animals supporters of animal testing say the 1000 organs of humans and animals function in a similar way but worldwide 95 percent of drugs tested successfully on animals fail in human trials good alternatives that don't involve animal suffering actually be more precise. these a miniature artificial organs part of the modular construction system that replicates human body parts. blood lungs and liver or high quality and is

using them to test new medication. but this system enables us to trigger a paradigm shift in drug development that is an organ of this organon a chip system means we're able to determine medication more quickly and cheaply and where it's needed and to the patients with the enemy. in future this could eliminate the need to conduct so much testing on animals on average the development of a single medication currently takes 15 to 20 years that's largely because animal testing is time consuming costly and controversial and often the results can't be applied directly to humans unlike with the organ on a chip. to create these organs the researchers cultivate skin tissue cells they're then infected with a virus that introduces 4 gene sequences into the skin cells and. reprogram some of

them these then become i.p.s. induced pluripotent stem cells through the addition of growth or differentiation factors they can be transformed into any kind of cell in the human body from the heart and lungs to skin and deliver. these influential this chip can combine to organ models you can see the organ compartments here and here they are connected by a common circulatory system the 2 little chambers here comprise the pump which functions like the human heart and even if you just mentioned here how this lets the organs communicate with one another and exchange neurotransmitters and with and observe this interactions or god of. their researches don't reproduce the entire organ only the parts all cells which should or could respond to a certain drug. liver cells for example

a cultivated unused in an organ storage container at $37.00 degrees celsius mirroring the temperature of the human body they left to grow and develop in lifelike conditions under the microscope the researches can see even function just like in the human body. unlike with animals or people we can look inside the chips at any time with a microscope and see with the liver does with the medication does it tolerate the drug or is there damage mechanically on sean and then i can also see on the other organ here in the heart liver or pancreas or that these products have an effect whether they can be helpful in healing illness or maybe produce side effects it's all in the. major advantage is that the substances can be tested directly on human cells so in contrast to animal testing the

researches can gather reliable evidence about the effects on people. that's because tests on rats and mice can only predict whether substances a toxic to humans just 43 percent of the time so most medications that were tested successfully on animals fail when drug studies have been conducted on humans up to 95 percent of all drugs trial and. these 2 neuroscientists have developed another alternative to animal testing they can simulate on the computer how a medication or substance affects the conduction of stimuli in the brain. the nerve cells in the brain structures that we study are also affected by alzheimer's disease and epilepsy which is why it's important to better understand the mechanisms of such diseases in these regions of the brain and computer models

are quite helpful in this case the cells of fly larvae form the basis of their work biologist how men could 6 am and a structure very closely while he to get lit focused on the electrical characteristics then they compared them with the sounds of other animals. i. here we have a worm cell that's a couple hundreds of a millimeter in length all the way to motor neurons to cuts a motor and i want you to from really made her lungs and wondrous which is one of i and what was really unexpected was that although the cells are extremely difference in size and in terms of complexity and shape they all behave the same way complexity to. own foreman for height and plies the cells they analyze come from animal tests conducted and published by all the scientists. for didn't fund using for each of these

little dots here i'd have hunted do animal tests and that would have been impossible because we have $6000.00 cells here extols and. instead with the help of this data the scientists have been able to create a computer simulation of the brain with all it's not cells and neural pathways. the monkey on computers either computer delivers a nice reproduction of all the details. about the cells or so well replicated expect sports can no longer tell the difference between the real cells and the artificial wondrously. as a result the opportunities for testing a virtually endless diminish that come on on the computer you can run through all kinds of combinations which you could never do in an experiment. to research as a noun developing computer models for human cells as well in future that could eliminate not only the need for animal testing but clinical studies on people tune

. back in berlin research as can already replicate 11 organs on a scale of $1.00 to $100.00 thousands now that testing how they can be networked and the supply systems fully automated using a prototype. just doesn't run. muscles which. can do everything that happens during studies you have. the foot on the chips and you can take samples from these chips and administer the medication. so i can tell it to apply the drug via the skin or administer it as a tablet via the bloodstream through the intestinal barrier. and we can also try to inhale it in some but all the different means of application you're familiar with from the pharmacy and from sprays through to shots and creams can be simulated here so my claim coming in from. the research is estimate this system will be ready for

use in one to 2 years. it won't be possible to completely replace testing on humans and animals in full seeable future due to factors such as pain and emotion simulation but the chances are good that it could replace up to 60 percent of all animal testing. because it is red white object but only very occasionally. do you have a science question you'd like us to answer send it to us in a video text or voice mail if we answer it on the show we'll send you a little surprise as a thank you come on just stuff. you can also check us out online dot com slash science or on twitter ask d. w underscore science. boubacar dan from ghana asks just how closely

related we humans and chimpanzees. are very closely some 98.5 percent of our d.n.a. base pairs are identical based on average findings from a range of analytical methods. and our genetic match with gorillas. it's just one quarter of a percentage point less than that. around it turns branched off from our common family tree earth or earlier but they still share 97 percent of their d.n.a. with us so how do we explain the huge difference between humans and apes. some primates can scale trees in the rain forests. while another species exploits other planets. human genome contains some 3000000000 base pairs of which just 40000000 differ from those of chimpanzees but this vital difference means that

certain proteins in apes have other structures and possibly other functions in the body. but for all the differences there are also many similarities using tools to eat food with for example. chimpanzees use twigs to provide delicious ants from their nests. and chimps are emotional creatures researchers have even found similarities in the sound of their laughter and ours. they understand symbols and can learn for example which one beats the other in a game of rock paper scissors. but chimpanzees will probably never be able to build computers although then again neither can most of us the famous primatologist jane goodall urges us to use our supposedly superior intelligence to start protecting the habitats of our primate cousins and the planet

as a whole. the dental a thing that humans share more than 98 percent of their d.n.a. with gorillas and chimpanzees might sound like a loss but when you consider that the human genome is made up of billions of d.n.a. base pairs the 2. percent different still accounts for a lot of variation in. another example humans and pigs share 90 percent of the same genes. are most popular 4 legged friend shares 84 percent of our d.n.a. . and even the round worm has a 75 percent similarity. stranger still 50 percent of human genes also have counterparts in bernauer on.

both bon appetit. how long did the terminator arnold schwarzenegger work on this legendary seemed to get it just right even then he couldn't get rid of his austrian accent a new study has revealed just how difficult that would be. the boy forgot his book. the train is moving fast. a phonetics researcher at the lute remarks 1000000 university in munich he felt fine ish and our colleagues had 24 native german speakers read out simple english sentences. supposedly our hypothesis was that one of the reasons it's so difficult to improve our accent in foreign languages is that we can't hear our own false pronunciation as well as we hear it in others and that's

what we're trying to test by asking subjects to read sentences and then write their own accent as well as the accents of others. but before they played the voices back to their test subjects the researchers manipulated the voices so that it sounded as if men were speaking. that was important to us we wanted to see how people judge themselves without knowing that they're listening to themselves. for example this recording the boy forgot his book became this one on the board for. each test subject a bell you waited for of the male voices one of which was their own and the evaluation confirms the hypothesis as is the result was that the test subjects did in fact evaluate their own pronunciation better than the others even though they weren't aware they were the ones speaking. why is this and what are the

consequences. as i can go on 1st of all were most familiar with our own pronunciation so that's the one we understand the best and the accent we understand the best usually sounds better to us as on hand and that's the mere exposure effect which means that the speech we recognize well and that we've gotten used to is the speech we find better that's an interesting read one of the conclusions that we've reached is that it might be difficult when prove your pronunciation if you evaluate your own accent is already good enough. times even then you can't see how you can know why you should improve it and. maybe these findings will help language students in future. here's the fun fact when dinosaurs roamed the earth there were no flowering plants just ferns and conifer. flowering plants came around 16000000 years later the

1st flower is thought to have looks rather like a water lily today we have flowers in every shape and color many of them use sand to compete for the attention of insects but they also use another method electrical signals. bumble bees are drawn to flowers quite literally there's an electrifying sense of attraction between insects and flowers going to be approaches a blossom the latter is pollen jumps across and attaches itself to the fine hairs line and the bees exterior. professor danielle bad from the university of bristol knows all about this magical connection between plants and their pollinators if you sit by. and you look at bumble bees you realise pretty soon that dental demanding randomly on the flowers

they don't visit the flowers immediately after somebody else has been there little to go to the flowers that have not been visited for a little while that's because these flowers will have generated next time the mean time to keep working at producing nectar and i suspect the bees no doubt. over millions of years plants and their insect admirers have developed a win win relationship receive nectar and pollen in exchange for pollinating the flowers. flowers can not afford to disappoint b.c. this is the the key the key thing here is that it will be arrives they invest all the energy and state so do the search flowers all have a means of saying i've. known. calif they cannot change colada cannot change center very quickly they cannot change the shape very quickly you can change the u.v. reflections which we know is also important but what can be changed so in the

course of research we sort of figured out at some point that one thing that can change very quickly is the electric potential of flowers. flowers and insects electrical signals to let them know whether their blossoms are full of nectar or empty. to prove this hypothesis. first turned his attention to the flowers. we have measured the fact that flowers are negatively charged they are grounded to the to the ground to the floor to the soil which is rich in electrons and these negative challenges even if shown as if you won't form the soil will move into the flower so the flows tend to be negative based tend to lose electrons when they fly this is one of their properties as if rice through the year they rub against the air and they will shed and a troll is therefore they will be positively charged. in the

lab don't you obey i was able to prove that bumble bees can sense electrostatic fields with the help of his institutions own big colonies. insects tested already reacted to tiny amounts of negative charge at feeding stations researchers had set up to simulate flowers reaching nectar. the sensory biologists can even listen into the communication between flower and be yes it's yes. they connect a flower to an extremely sensitive measuring device the loudspeaker then translates the electrical charge into sound. so you can kind of consider a magic wand i guess. it's just simply a plastic world and you know when you rub your head with a balloon and you get all this electric charge building up and your has stands on

and that's essentially what we do with this so you can rub it on your hat and you get a lot of electric charge building up and this is a charge that would be similar to the charge you get on a bumblebee that's flying around say we can use this is a nice sort of mimic for bumblebee flying around. depending on the distance of the wand the sound becomes louder or softer the devices have now been checked now it's the bumblebees turn. the experiment shows that as soon as it touches down the charge between the bee and the flower is equalized. so any bees flying by afterwards know that this flower has already been visited and has nothing to offer only after a time when the flower produce more nectar and regain its negative charge this is what we are after what we want to find out is how did these electric fields get

created between themselves and the flower so in order to do that we need to immobilize that be put it on this is our platform then our ranch to. each side of its head to a ploy in the voltage between. the experiment takes place in an enclosed environment in a lab that's impervious to external vibrations with the help of a laser beam don't you even measure nano scale movements. he suspects that the bees hairs and tenney can react to these differences in voltage. the vibrations we can see here on this is a graphic representation of the data we got but it's exaggerated in amplitude so that we can see with our eyes in reality it isn't and the little hairs that we've seen before are actually vibrating a fraction of their own so this is not motions that we can see but certainly

motions of the insects can perceive scientists have still been unable to locate the sensory organs that allow the bees to perceive these tiny movements but one thing is clear the seemingly magical attraction between bees and blossoms all really know all i think this is a big gain for us to try to understand that new dimension which is hidden from us we don't detect these fields but that hidden dimension that may exist between flowers and they're put in it was but it could also well be that. was that all the plants and all the insects also use for reception in in different ways so this is for us to explore now and to try to see how much more generalized perhaps this process of detecting electric fields is in the small world of insects and plants. for beasts these electrostatic fields are a vital navigation tool. they guide them straight to flowers where they can tank up on nectar ensuring

a most fruitful journey. and that's all from tomorrow today thanks for watching on do join us again next week for more fascinating stories from the world of finance and research until then it's goodbye and take care.

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this is news coming to you live from the u.s. president trick or trying to change an election result. nothing wrong with saying that you know. 2 that you've recalculated. presses the election official in the state of georgia saying he needs to quote. the president still refuses to concede the election won by his democratic rival joe by also coming up. under

fire for its coronavirus strategy despite tougher restrictions in time.