to do it just needs to be further and it needs of course to be working with other countries to move in the same direction jennifer morgan from greenpeace international that will finally the vatican unveiled its christmas tree on some peter's square on friday evening we'll leave you now with pictures from that ceremony. thank you your name. the fight against the corona virus. has the rate of infection been developing. the latest research. information and context. of virus update.

has a virus spread. through the town. and the weekly. show is called spectrum if you would like any information on the cloning or any other science topic you should really check out our podcast where ever you get your podcast you can also find us at. the holiday season is a time to celebrate and to be around loved ones but this year everything from christmas markets to family gatherings is having to be scaled back due to the couvade 19 pandemic. social distancing and other restrictions have left many feeling less than festive so what should

a good christmas look like. this is d w 19 special i'm joined on as germany grapples with yet another record number in coronavirus cases it's weighing up how best to allow for merrymaking well keep. the virus from spreading and all across europe it's a similar picture people are breaking with tradition as they change their plans to accommodate restrictions take a look here. normally we travel to madrid on christmas eve and stay for a few days this year we have to celebrate at home but we'll have entertainment from our grandson where there are children there's christmas for him learning i know you don't really want them but we'd like to organize a big party with our friends but i don't think that's possible family that's all there is to it here in this venue or city of sin the christmas lights that you see behind me stay off at the moment even at night this city administration is afraid

of big crowds that might come in to watch the general restrictions for christmas in spain i'm not clear yet but everybody knows this would be a very different as the season even in my own family which is partly german and partly spanish we don't know what to do yet and if we will be able to meet each other it's. not traditional approach that would be nicer to go to the christmas market but i think these measures are sensible and more important now next year we can catch up on our traditions again so i have no problem with the 3 of us it's difficult to usually celebrate with my husband's side and also my side together now we have to split everything up so that she her households come together already as a pharmacy employee i always have to be very cautious not to bring the virus home and so there's no choice but to put things up this year so you can shop with my family we've all agreed to take coronavirus tests before we meet at home and if they all turn out negative we come together if not then out or in smaller groups.

kind of with a gun i want to hug my family again. here normally at this time of year the place behind me would look totally different that would be lots of christmas market stands and the smell of roasted elm. everywhere to get you in the mood but what i personally miss the most this december is meeting friends in the evening and drinking while trying to get the only thing that cheers me up this year as mulled wine to go serious and merry christmas now how to strike a balance between necessary interpersonal contact and the required social distancing is a big question for many of us as the christmas holidays get closer here to help us understand this better is to again who is she is an associate professor and clinical psychologist at the australian national university thank you very much for joining us to again now according to research our risk perception during an

encounter with a person depends on how well we know them why is it that people find it so hard to take the necessary covert precautions with the people we love and it's something we've been looking at for a number of years in our research group and one thing that we've found is that this is consistent relationship where people much more willing to take risks with the people that they are closest to the ones that they love and that seems to be because we humans are hardwired to use that sense of social connection we have to others the groups that we belong to and the communities that we value we use that as a huge as a safety it's a signal that we can trust someone and that they are safe person for us to you know put our life in their hands and in some ways that makes a lot of sense you know if you're looking for someone to take care of you shield or your closest networks probably other people you can trust the most on the other hand when it comes to the spread of a contagious disease it doesn't make

a lot of sense and so i think that's what we're seeing here is that out instance to trust those that are closest to us are actually undermining our safety when it comes to president. our hard or wired instincts of putting and putting us at risk of that can be quite a quite a problem but can you tell us ian how did you come to these conclusions. yeah we've been getting a series of studies over a number of years on including befall kovac that we were we were interested in this over the last few years and then a few studies looking at reception but we've also looked at it since the pen demick began and one nice opportunity we had to do that was a study that we had running at the beginning of march when looking at neighborhoods and people's connections their community and the original intention was to look at people's sort of the patient and community events but when the pen demick really game steam in march we changed the purpose of one particular project in order to look at how this particular research question around the link between

a group memberships the trust we have in others and now risk deception and what we found was that in out the sample of a couple of 100 people in australia the stronger the people identified with the local neighborhood in the community before coded so in early march the more likely they were to trust the night is in lockdown which sounds like a great thing but the problem in this case with trusting one's neighbors was that that also predicted that they were 'd more comfortable being in close contact with those neighbors so breaching physical distancing recommendations for instance and spending time in the physical presence of the neighbors felt safe because they had that trust in their neighbors so that would be an example of one of the studies they've run looking at this link with social connection and the sense of belonging we have with others which is usually such a protective and positive thing can actually undermine our capacity to respond to a pandemic of this century. indeed and if social contact is needed to stay healthy

but at the same time it puts us at risk what are we to do then. yeah it is a bit of a catch 22 i think because i certainly wouldn't want to say that social connection isn't important i think it's one of the most important things when it comes to placing our health and indeed a mental health over the long time and it's also the case that people who are most vulnerable to co the 19 publications are often the same people who are vulnerable to loneliness to isolation and to poor health consequences that we say as a result of that one of the things i think that 2020 has really necessitated for all of us is to be creative about how we stay connected to one another whether that's through using virtual mains in ways that we might not have considered prior to the shia all whether it's you know choosing to get together outside or in a in a socially distance more safe way of getting together and saying our out close these contacts i think we need to find compromises that allow us to stay connected

while taking as fewer risks as possible when it comes to that you've written that the critical role of shared identity and therefore of higher risk taking has been under recognized in public health messaging how exactly have public health messages change in your opinion i think that there hasn't been much attention to the the difference between the risks they are willing to take with strangers on public transport at now communities versus the risks they are willing to take within the outposts networks with our families and without friends and the problem with that is that we're actually very very ready to accept the risk of strangers but much less ready to recognize and accept the risk and how close it's networks and in fact that's exactly exactly where the vast majority of covert transmission is happening it's happening in households it's happening at small gatherings of family and friends so i think ideally i'd like to see public health message age really be a bit more focused on how we can reduce those risks in our closest networks and how

we can celebrate important milestones like birthdays and christmas without putting the people we love into. so social this is taking protecting the people you love thank you very much that was teagan crew with she is an associate professor and clinical psychologist at the australian national university thank you for your time and insights today thank you know. and for the final time this week our science correspondent derek williams answers one of your questions. for a 20 year old was the risk of taking a vaccine compared to not taking and. most of the questions i'm getting at the moment involve potential vaccines and this one is close to the top of the list the experts i've read who discuss this topic make several important points and 1st of all they say you should look at the numbers that we have so far like the data showing that for tens of thousands of people in 3

big vaccine trials there's been no reported serious side effects although there and by and that those test subjects didn't have known preexisting health problems for people who do there could be more risk involved we just heard for example about a couple of cases of people in the u.k. who had preexisting allergies having a bad reaction to one vaccine but the experts still say that the potential risks pale in comparison to the risks involved in catching the virus sure a 20 year old is a lot less likely to die from covert 19 than an 80 year old is but but some do why take that chance if we have something that medical authorities say can safely protect here which brings me to point 2 even if a young person is much less likely to die from the disease there's also

a chance that a covert 1000 infection could cause long term health issues by some estimates up to a 3rd of those who recover continued to have more chronic complaints that that doesn't seem to be age dependent so so young people have them to point number 3 getting vaccinated also. has a social aspect which is that it could potentially help protect the people around you though though that question granted is still up in the air still expectations are high that if vaccines stop people from developing fully fledged covert 19 they'll also help cut down on transmission and that will slow down the pandemic for all of us finally don't forget that young people who aren't in essential jobs will be pretty far down on the list for vaccination in most countries by the time most of them can get a shot we're going to have

a lot more information about any potential serious side effects but but based on what we know now most experts expect those to be very rare. do you have a question for derek just send an e-mail to feedback taught english at v.w. dot com and type expert in the subject line or leave a comment on our you tube channel that's all from us thanks for watching face think especially during the holidays by for now. at 1st glance it looks like a scrap heap. but on the 2nd. goldmine. valuable metals are found in alice in the trunk devices. researchers in germany want to separate them from the school in the most environmentally friendly way. their

spirit takes with highly specialized bacteria to. 250 year old pulled the music stopped they told. him his anniversary year he remains a powerful name. everyone's lips. are either of the inspires really projects to this day or 20. 30 minutes t.w. . i tell.

you is the solution for inside africa luck. fantasy this. was. the scene of the boy in a trench. lashed. secrets cuts starts december 26th below. our planet contains many treasures we extract metals and minerals from the ground to use for building roads machinery and computer chips all our technological progress depends on these resources but supplies of raw materials are not infinite in many cases mining them poisons people and the environment and yet the

electronics industry critically relies on them how can we continue to develop technology without draining our world's resources to. welcome susan morrow it's a day this is science so i'm t.w. oh. this is according more. chemist engineer and entrepreneur back in the 1960 s. he formulated what has become known as moore's law roughly speaking it says with a number of transistors on a micro chip doubles every 2 years vaccines computers steadily become more powerful more predicted but the trend would continue up to now it has computer chips are getting even smaller a team of scientists in germany has now found a way of downsizing microchips still there. it's a simple fact of modern life electronic gadgets get smaller and smaller and they're

able to do more and more that microprocessors a constantly becoming by is tiny powerful. computer chips to down size is not a matter of magic it needs the brains of people like the painter kurtz. and sick in together as part of an international network they've taken a huge step to even smaller chips. but how a computer chips made in the 1st place in principle it takes something like a project into the chip circuitry is stenciled on to the side but instead of projecting the picture onto a screen you focus it onto a silicon wafer with a light sensitive coating plus. the image can then be developed much like a photograph and at the end you have your computer chips. with technology we can know integrate over 16000000000 transistors onto

a microchip that's smaller than a finger chip. but what kind of components do we need for a projector we need a light source and an optical system fi consisting of lenses and mirrors. let's start with a light source light is an electro magnet. tech waves and waves have a wavelength red light has a long wave lengths blue light a short wavelength and ultraviolet light a very short wavelength but what does that have to do with chip manufacture roses mohan hopper tartars put simply a long wavelength means large structural size a short wavelength means small structural size. and you are trying to extreme ultraviolet light or you re has a wavelength of 13 member half nominators. that's less than a 10th of previously large wavelengths. you can create images of

structures in much sharper resolution. it takes a laser to generate a u.v. light but how does that work to begin with you have to build the world's most powerful industrial pulsed laser it's a technological masterpiece it produces a high intensity light pain but not even yet. to get that you need to train a laser beam is aimed at a droplet of liquid tin the high energy light heats the tin 222-0000 degrees celcius transforming it into a plasma which radiates the desired. the pulse laser does that $50000.00 times a 2nd. so that takes care of a we have a light source 'd what's missing is the optical system being. glass lens is

a no good for the task they only transmit certain wavelengths and not one of them. the solution is to use curved mirrors instead of lenses the light only has to reflect on the surface it doesn't have to pass through. the mirror. ground from glass blocks like this and then polished surfaces are incredibly smooth. if this marriage was scaled up to be the size of germany its biggest irregularity would be barely a 10th of a millimeter deep. but it's not just about grinding and polishing a mirror requires a coating. and this equipment gives the merest glass surface extremely thin coatings of silicon and molybdenum. there are only a few atoms thick but the research is apply as many as

a 100 lay is why is that. if the mirrors coating is too thick then it will absorb too much of the light. this is but it's still a huge struggle to get a good reflection using layers deserve should. fear radically the maximum reflectivity least 75 percent as far as i know. minus was. in prior to true for around 70 percent. reflectivity is a measure of america's performance and 70 percent is a great value. the magic lies in constructive interference which works like this and beam reaches the marrow part of this is reflected from the rest penetrates the top layer to reach the next more mis reflected the rest penetrates to the next

layer and so on if the layers all have the correct thickness the reflected light is amplified. now the light reflected from the mirror every chiz the silicon wafer and the next generation computer chip take shape. for 20 years it's a great feeling to hold the gadget in your hand with an e.u. reach. inside and to know that we helped develop the technology that made this kind of chip possible. the trio of scientists was awarded the prestigious gem and future prize for their innovation that technology is already in use the latest smartphones carry chips fashioned with extreme ultraviolet light it's just one more confirmation of moore's law which says the number of transistors that fit on a chip doubles every 2 years. olds in the 20 teens people started saying that the limits of moore's law would be reached. and it wouldn't be

possible to go any further for. technology we now have the technology with which we can continue pushing moore's law over the next 10 years. a lot. of. good feeling. one valuable commodity used in modern electronics is gold it's a highly efficient conductor that doesn't rust and hardly react at all with other elements. in estimated 200000 tons of gold have been mined to date. the search for gold has led to bloody conflicts in many regions and the process seems involved in extracting it pollute water and soil endangered people's health reason enough to come up with alternative ways of striking gold.

there's hidden treasure in this trash. germany alone generates a 1000000 tonnes of electronic waste every year and the scrap is a gold mine literally just look at this computer circuit board for example. gold conducts electricity better than copper take this gold plated edge connector the gold is used to ensure the best possible connection for high quality fast data transfer. these connectors have to be technically sound meaning the gold plating prevents oxidize ation and guarantees the best possible connectivity throughout the devices lifetime so i thought i know best movement here connectivity be it laptop or smartphone most electronic goods would be function without gold. the electronic waste from 5 computers contains

a total of one cram of gold that's actually a lot it's the same as the amount contained in 2 tonnes of. but mining it would generate huge amounts of c o 2 anough to drive a car 3 times around the globe. the greater the ecological footprint of a material or product becomes the more important it is to recycle but does recycling make economic sense and doesn't. we protect the environment our group uses a company that recycles medals including goals. the 1st stage involves shredding the waste and separating plastics from metals that leaves a mixture of metals which are melted down together in a furnace at $1300.00 degrees celcius the heavier metals gold silver and copper zinc together to the bottom of the melting vessel and can be poured off separately from the lighter metals above. the

heavy metals end up in place like these they're mostly copper but they do contain quite a bit of gold. going on for stents wife 2 of these plates way just under $800.00 kilos has one troy ounce of gold distributed throughout those plates 31 point one grams aims to extract it with a minimum of loss so excited. each strachan process uses a lot of chemicals the plates are dipped in a sequence of acid baths each of which dissolves a different metal from the mixture 1st the copper then silver last of all the goals . are rupees won't let us film the last stage of the process that's a commercial secret. recovers 18 tons of gold a year from electronic waste it's evidently

a lucrative business but it's impact on the environment just less beneficial the assets have to be disposed of in an elaborate process and the smelting furnace churns out large amounts of c o 2. but recycling gold might soon become more environmentally friendly industrial biotech company brain is working on a completely new method it's using bacteria to recover the gold from the electronic scrap even though by. tyria normally avoid the precious metal like the plague. in this highly i think even noble metals a not very reactive and that anti microbial so it's a very special property if an organism can survive in high concentrations of the metal but quite apart from being able to get a metal into solution esther got bore and her team experimented with thousands of bacterial strains till they found a suitable candidate they've dubbed it pseudomonas but tabu solvents meaning metal

solving pseudomonas bacterium. the researchers at brain demonstrate how the gold is extract in a plant they've developed and dubbed the bio extractor. the biological miracle takes place in this fact. first polarized electronic waste this black sludge is mixed with a lot of water then the mixture is an ocular lated with the bacteria which are suspended in a yellow liquid. thanks to nutrients in the water the bacteria thrive and we can. but how do you get the gold out of the water. that's the job of the 2nd type of bacteria in these pellets they soak up the gold like a sponge. the

pellets are then burned off that leaves a residue of small but very pure gold nuggets. differences like the process takes place and a very gentle kind we work at room temperature the bacteria become active at $26.00 degrees celsius the biological process releases half the amount of c o 2 compared with the melting process the bacterial approach is safer and more eco friendly than the smelting and chemical processes the next stage is to scale up brains brain the solution it may look very promising but it's too soon to say whether the bio extraction methods will win out. to mine gold or other precious metals you usually have to blast your way through masses of rock. but how

did these raw materials get there in the 1st place many chain from hot fluids flowing through cracks in the earth's crust these deposits got pushed up with other layers of rock to form impressive structures if you were from genuinely wanted to know more. the rocks grow. crowds like these consist of hard compact style often in bizarre formations they're considered immovable and immutable like the old saying solid as a rule. but snow when i see wind and rain gradually where a way the rocky peak of a mountain. it gets ground to pebbles then sand and finally to settle the process of erosion the silt has carried away by water and often ends up in the ocean as settlement on the seabed. over millions of years the must become stents and cement into sedimentary rock. where 2 or more of earth's tectonic plates are pushed

together the sedimentary rock on the edges of the plates pushed upwards to form a mountain chain. but the rock doesn't grow again maps it merely alters shape. back at the peak again erosion begins itself to work the geological cycle starts over. rocks to form and grow when for example calcium carbonate precipitates out of the water from a spring like this one in southern germany. limestone deposits which together with moss and blow out create a firm crust that is impermeable to water. thus the rock does grow a few millimeters a year thanks to the calcium carbonate. the same process can be seen in caves. where the water borne deposits forms that look tights which grow downwards from the roof. and stuff like might switch grow up

towards. the rock crystal or quartz found in the alps can also grow in a similar way as does limescale in the shower. and even the tartar on our teeth. it's formed by the mineralization of dead bacteria and dental plaque. the oldest known rocks on our planet are located in canada the cast a nice complex is more than 4000000000 years old a look back into our planet's prehistory the outcrop was formed what it was all. or 900 degrees celcius. the earth was pretty wild back then a multi planet bombarded by meteorites the salt that we now use to season our food was also formed back then. 4 and a half 1000000000 years ago all planet was

a red hot mass as it cooled volcanoes hold matter from its in a most court to the surface liquid rock rich in sodium gushed from fishes in the earth's crust and the gas clouds from the volcanic craters contained not only water vapor but chlorine. it remained in the atmosphere until the air cooled enough for the 1st raves. the chlorine was washed down with the rain into the rivers as the water flowed from there into the sea it passed over volcanic rock containing sodium. the water leached out the sodium meaning the primordial ocean now contained both sodium and chlorine. as the sea evaporated in many areas over the course of millions of years it left behind sodium chloride otherwise known as cells. and the process continues to this

day the sun evaporates the water and sea salt is left behind and on very hot sunny days with steady winds particularly fine crystals form the coveted. today's salt from ancient oceans is also found far from the sea the movement of the earth's tectonic plates pushed the salt by the time high at elevations. deep into the ground. so all. our salt originally hails from the seas and oceans one of the oldest ways of harvesting this vital interior is by allowing sea water to evaporate in basins salt crystals are left behind. but much of the salt formed millions of years ago now slumbers beneath the earth's surface we visit

a walk salt mine in western germany to see how it is extracted. from that to fill need about 100 seconds to get to the bottom we're moving at 10 meters per 2nd. left him on heads the salt production here 900 meters below ground today they want to extract 8000 tons of salt from the mine and that calls for some unusual measures. we going to blast chamber 911 of our biggest a bit specials let's see how it goes. checking in and out is especially important when blast work is being carried out underground but 1st the work has to be planned this is chamber 910 blasting here requires an entire team.

but they'll also need to work at 2 other locations in the mine to reach the day's target of 8000 times. the mine is a vast labyrinth of tunnels and chambers 900 meters underground each day it expands a little further. before blasting can proceed in chamber 910 more work is needed elsewhere where the team won't meet its target. let a man doesn't need a g.p.s. to navigate down here i know i've been doing this for 32 years i'm in my element down here in the salt we're nearly there like there's the loader. the wheel loader can pick up 20 tons of salt at a time it's so pure you could sprinkle it straight onto a boiled egg and eat it. as soon as the salt has been loaded up the roof of the chamber needs to be secured. first any loose rocks are scraped off the surface.

supporting anchors up to 3 and a half meters long are driven into the roof to prevent collapse. conditions are tough it's a stifling 40 degree celsius and the salt makes the air dusty and dry. at least that also means that nothing down here rests. just one hour to go to detonation. only cause it looking. good we're on schedule but we need to get over to chamber 910 to prepare for blasting. the tunnels and chambers here in the salt mine are usually 7 meters high. but this is the one big exception. chamber 910 is 20 meters high. they're going to blast this ridge

poles have already been drilled for the explosives. it's the moment of truth the explosives team moves into position. they normally blow up smaller walls . for this one they need half a ton of explosives. first detonators are placed in the drilled holes then explosives are inserted deep into the wall. the detonator wires are magnetic so their fragments can be retrieved from the salt afterwards. then it's time to move to a safe distance 3 kilometers away. all the leads come together at this central ignition point now they just need the final go ahead. you go hello jaeger here is everything clear. ok we'll get

started. ohms reading good let's go. then. oh. wonderful that was very good. we drive back to the blast site let him on now needs to check the loose material that's been created by the explosions oh that looks good. to freeze happy yeah that's a feat yes very happy it worked with you to flee the size and shape of the boulders

is ideal a very good result this ought to be able and we're the 1st humans to ever hold the solid rock in our hands it's 250000000 years old there you go a gift for you thank you. and if you know how some of us here are the nearly this is 1500 pounds that's what we needed to reach our goal of 8000 tons for today i'm very happy that. if our old one is right why are great but i'm a bit of a. if you have a science question that's bothering you send it in as a video text or voicemail if we answer it on the show you'll get a little surprise as a thank you just asked we look forward to hearing from you. for more science stories check out our website e.w.

dot com slash science or look for us on twitter. that's all for now from tomorrow today your science program m d w thanks for joining us we'll be back next week until then stay healthy and stake here yes.

250 year old global music star beethoven. in his anniversary year he remains a powerful name on everyone's lips. senior guys are who inspires thrilling projects to his declasse parts 20 more. coming up on w. christmas is cancelled not so fast. we

heat up the others and bake some cookies. to bloggers with a sweet tooth invite us into their bakery may share their favorite recipes with us and some valuable tips for making traditional christmas cookies. your romantics. in 30 minutes on d w. w's crime fighters are back africa's most successful in radio drama series continues this season the stories focus on hate speech color of prevention and sustainable charcoal production all of a sow's are available online and of course you can share and discuss on africa's

facebook page and other social media platforms. crime fighters tune in now. get. in the phone. north. beyond the inhabitable world. it's lonely. veteran. and breathtakingly beautiful the arctic powerful expanse of bitter cold. and the sound of global warming. we took a journey around the north pole. profiteers and talk with people experiencing a changing environment or the ice disappears earlier and it keeps retreating to chase here's the last years have been smoldering russia. makes it hard which makes

it. our future depends on what happens here in one of the most fragile ecosystems on earth. northern lights within the arctic circle starts december 21st w. this is d w news and these are out top stories u.s. regulators have approved the use of the bio on take 5 the covert 19 fact same preparations for mass distribution are already underway the trumpet ministration had reportedly told the head of the food and drug of mr.