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Sono molti gli animali che si sono lasciati addomesticare da noi esseri umani nel corso della storia: la convivenza con i cani è cominciata oltre 33mila anni fa, quella con i gatti intorno a 10mila, quella con i cavalli da più di 5mila, per non parlare di mucche, capre e via dicendo. Ma ci sono specie che sembra stiano sperimentando qualcosa cui non avevamo mai fatto caso prima d'ora: si starebbero addomesticando da sole. Una tra tutte? I bonobo (Pan paniscus).

Volpi gentili Coccole di bonobo ...e grandi

Per Brian Hare, antropologo evoluzionista alla Duke University e autore di uno studio pubblicato su Animal Behaviour, si tratta di un vero e proprio processo di selezione naturale contro l' aggressività. “ L'idea che una specie addomestichi se stessa è un po' folle, ma ci sono alcune specie che riescono a dominare su altre proprio diventando più mansuete”, ha detto Hare a Wired.com.

Nei bonobo i ricercatori hanno colto alcune caratteristiche tipiche delle specie addomesticate: innanzitutto, rispetto ai loro cugini scimpanzé (Pan troglodytes, le due specie si sono divise circa un milione di anni fa) , questi primati hanno un'indole molto più gentile; inoltre mostrano particolari cambiamenti nello sviluppo e differenze anatomiche analoghe a quelle esistenti tra le specie addomesticate e i predecessori selvatici, come denti e mascelle più piccole.

Infatti, come ricorda Wired.com, la perdita dell' aggressività è l'essenza della domesticazione. Questo processo coinvolge i sistemi endocrino e nervoso, porta con sé mutazioni in diversi network di geni e genera una serie di cambiamenti anche nel fenotipo. I biologi la chiamano la s indrome della domesticazione.

Uno dei più grandi esperimenti che ha dimostrato in modo inconfutabile gli effetti della domesticazione è quello partito nel 1956 e che si sta conducendo ancora oggi in Russia sulle volpi. In questo studio, che coinvolge circa 130 fattorie, solo agli animali che si mostrano più tolleranti alla presenza umana è concesso di riprodursi. Ebbene, in soli 50 anni le inafferrabili volpi sottoposte a selezione sono diventate come cagnolini giocherelloni che adorano farsi spazzolare la coda. In pratica hanno mantenuto i classici tratti dei cuccioli, che normalmente scompaiono con la crescita. Anche il fenotipo ricorda quello dei piccoli: manto macchiato, orecchie pendule, coda riccia e zampe corte.

Torniamo alle scimmie. I maschi degli scimpanzé sono spesso in lotta per il posto da capobranco, mentre i maschi di bonobo raramente combattono gli uni contro gli altri. Anche nei comportamenti riproduttivi, i primi sono violenti con le compagne, mentre i secondi no: in generale, sono più inclini al gioco e a scambiarsi favori durante tutto il corso della loro vita. Secondo quanto riportano i ricercatori, anche alcune aree cerebrali considerate fondamentali per il comportamento, come l'amigdala, mostrerebbero arrangiamenti diversi nelle due specie.

In pratica, è come se l'evoluzione avesse agito nei bonobo in modo analogo ai russi con le volpi.

D'accordo con Hare è Richard Wrangham, primatologo e co-autore dello studio: quelli osservati  sembrerebbero proprio segni di domesticazione. Ma come potrebbe essere avvenuto questo processo? I biologi pensano che la risposta stia nei gorilla. Scimpanzé e gorilla hanno infatti condiviso alcune aree per molto tempo nel corso della loro storia, dovendo competere per il cibo: come indica il Wwf infatti, i bonobo vivono a sud del fiume Congo, mentre gli scimpanzé e Gorilla stanno a  nord.

Ad un certo punto della loro storia evolutiva, anche i lupi più docili avrebbero trovato un vantaggio rispetto a quelli più aggressivi – fa notare Hare – potendo occupare una nuova nicchia ecologica ai confini degli insediamenti umani.

Il fenomeno potrebbe essersi verificato in moltissime specie. I due scienziati sottolineano però che questo è solo uno scenario plausibile: quella dell'auto-domesticazione resta, almeno per ora,  un'affascinante ipotesi.

Fonte: Wired.it

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1. Uzbek government allegedly running full-scale sterilization program
 
A BBC investigation has revealed evidence of a government program to sterilize thousands of women throughout Uzbekistan – often without their knowledge. 
 
According to sources quoted by journalist Natalia Antelava, every Uzbek doctor is given a quota. One doctor said she must sterilize four women per month, but others said the figure might be as high as eight per week in rural areas.
 
A source in the Health Ministry said the program is meant to slow population growth. Medical professionals, however, said the real aim was to reduce the number of births and, therefore, to lower the rate of infant and maternal deaths in international measures.
 
Evidence also suggests that a two-year increase in the number of Caesarean sections, which make sterilization easier, is linked to the program. While official statistics say Caesareans account for 6.8 percent of births, doctors interviewed for the article challenged those numbers, with a chief surgeon at a hospital near Tashkent estimating the figure was as high as 80 percent.
 
In an official response to the BBC, the authorities denied the program’s existence, arguing that women are sterilized only voluntarily.
 
The BBC says forced sterilization in Uzbekistan was first discovered by pathologist Gulbakhor Turaeva in 2005. She gathered evidence of 200 cases, but when she revealed the data publicly, she was fired and later imprisoned, accused of smuggling opposition literature into the country.
 
2. Swiss story about Roma crime draws fire
 
A cover story about Roma published in a Swiss magazine earlier this week continues to cause outrage across Europe, Der Spiegel reports. The article, which was published 5 April in Die Weltwoche, carried the headline “The Roma Are Coming: Robberies in Switzerland” with the subhead “They come, steal, and leave,” a reference to an alleged increase in crimes committed by Roma gangs.
 

 
The photo illustrating the article, of a Roma child pointing a gun at the camera, contributed to the backlash. Livio Mancini, the Italian photographer who took the photo in 2008 in Kosovo, told a Swiss newspaper that Weltwoche had obtained the photo through an agency and used it without asking him.

Several criminal complaints against the magazine have been filed in Austria, Germany, and Switzerland, including by Austrian journalist Klaus Kamolz, who said he wanted to send a “symbolic signal” against the “blanket condemnation of Roma as criminals.” The Central Council of German Sinti and Roma also filed a criminal complaint with a German prosecutor for racial incitement and libel against the magazine and declared it would take steps to prevent its sale in Germany. The council’s leader, Romani Rose, accused the newspaper of equating a person’s ethnic origin with criminality, comparing the story with anti-Roma propaganda from the Nazi era.


 
In a video on the Weltwoche website, deputy editor in chief Philip Gut, who co-authored the article, said he didn’t understand the outrage caused by the photo. It was used, he told a Swiss newspaper, to illustrate “the fact that Roma gangs abuse their children for criminal purposes.”
 
3. Serbia arrests 14 for 2008 U.S. embassy riot
 
Serbian police have arrested 14 people in connection with the 2008 riot in Belgrade that resulted in a blaze that killed one person at the U.S. Embassy, according to Balkan Insight. In announcing the arrests, Prosecutor Zagorka Dolovac said her office had been investigating the suspects for more than a year. Some of the arrested were football hooligans known to have caused problems in the past, according to B92.
 
On 21 February 2008, hundreds stormed and set fire to the U.S. Embassy to protest Kosovo’s declaration of independence. In the process, protester Zoran Vujovic, a 20-year-old Serb displaced from his home in Kosovo, died of smoke inhalation.
 
The day after the arrests, Serbian Interior Minister Ivica Dacic said he had been kept in the dark about the operation. “I have nothing to do with this, because nobody informed me about it, which I consider to be impermissible. I consider this to be an absolutely poor example of doing things,” he told B92. Dacic also wondered why the arrests had taken place the day before the 11 April Belgrade derby, a soccer match between city rivals Red Star and Partizan.
 
Speculation about the extremely long delay in bringing the culprits to justice has touched on the suspected ties of some of the hooligans to political parties, who supposedly helped them escape prosecution, until now.
 
4. New pressure to free jailed Facebook activist in Azerbaijan
 
As one year passes since the arrest of a young Azeribaijani activist, new campaigns are sprouting up for his release. Bakhtiyar Hajiev was taken into custody in March 2011 and later sentenced to two years in prison for evading military service.
 

Photo from the Support Bakhtiyar Facebook page.

 A new video on YouTube purports to “tell the story of his persecution,” recounting that Hajiev had faced repression when he ran for parliament as an independent in 2010. During the campaign, he focused on the issues of human rights and corruption. But Hajiev and human rights organizations link the timing of his arrest to the activist’s role in organizing a Facebook campaign in the wake of the Arab Spring calling for a day of protests against the government and meetings across the country.    
 
At his trial, Hajiev said he was a conscientious objector and should have been granted the option of alternative service. His requests for parole have twice been rejected, most recently in late March, Radio Free Europe reports.
 
Students and teachers from Harvard University, where Hajiev graduated from the Kennedy School of Government in 2009, have also ramped up their protests. Almost 900 members of the Harvard community signed an online petition earlier this year calling for Hajiev’s release. And a 28 March editorial in Harvard’s student-written Crimson called on the university to do more to highlight Hajiev’s plight, saying, “Harvard University has failed to officially condemn Bakhtiyar’s arrest and conviction, or leverage its weight on the international stage to raise awareness about his case.”
 
5. In Chechnya, loose lips sink … taxis?
 
A new initiative in Chechnya hopes to put a lid on what some see as a growing social ill: gossip. The campaign was launched by the Chechen Government Committee on Youth and has been targeting mainly taxi and bus drivers, according to Radio Free Europe.
 

Ramzan Kadyrov

 

Campaigners have passed out bumper stickers to drivers with slogans like, ”Drive in silence, you’ll go farther,” and “The Almighty is against gossip,” according to the report. The group said the initiative was to help clean up the image of taxi drivers, who have “lost respect in the eyes of society because of their spread of disinformation among the passengers, ignorance of road regulations, and destruction of cultural values,” according to a statement posted on the group’s website.
 
Reaction to the campaign has been mixed, and many see Chechnya’s gossip-inspiring leader, Ramzan Kadyrov, as behind it, according to RFE. One man told RFE that the initiative, which he said harks back to the days of Joseph Stalin, has actually fueled more rumors about local leaders.


Joshua Boissevain and Ioana Caloianu are TOL editorial assistants. Jeremy Druker is TOL’s executive director and editor in chief. Anna Shamanska is a TOL editorial intern.

Source: Tol.org - Authors: Joshua Boissevain, Ioana Caloianu, Jeremy Druker, and Anna Shamanska

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Matematicianul Thomas Hair, de la Florida Gulf Coast University, a ajuns la concluzia ca fie noi suntem singuri în univers, fie extraterestrii nu vor sa ne contacteze.

Dupa calculele sale, pentru a ajunge la cea mai apropiata stea vecina le-ar trebui 500 de ani si înca 500 pâna ar reusi sa construiasca o nava spatiala capabila de aceasta calatorie. Cu alte cuvinte, civilizatiile formate în proximitatea celor mai vechi stele ar trebui sa ne fi vizitat pâna acum.

De ce nu ne contactează extratereştrii?

De ce nu s-a întâmplat acest lucru? Hair crede ca extraterestri au trecut, pur si simplu, pe lânga noi. El speculeaza ca extraterestrii ar putea sa nu fie fiinte biologice, ci creaturi care folosesc alte resurse decât cele cunoscute de noi, motiv pentru care nu au nevoie de nimic de pe Pamânt. Pe de alta parte, s-ar putea ca aceste civilizatii sa utilizeze alte rute în univers, rute stabilite cu multa vreme înaintea aparitiei vietii pe Terra.

Oricare ar fi motivul, Hair sustine ca suntem ignorati. Teoria lui indica faptul ca, daca o civilizatie care traieste pe o planeta veche de 5 miliarde de ani, cum suntem noi, are o tehnologie care îi permite sa caute alte planete, atunci una de pe o planeta care dateaza de acum 10 miliarde de ani cu siguranta ne-ar fi putut gasi pe noi.

În aceste conditii, compusii cloro-fluoro-carbonici (CFC) din atmosfera ne-ar fi dat imediat de gol. CFS reprezinta un grup de compusi care se gasesc în fluidele de racire si aerosoli si care elibereaza atomi de clor atunci când sunt expusi la radiatii ultraviolete si distrug stratul de ozon al Pamântului.

Woods Halley, de la Universitatea din Minnesota, care tocmai a lansat o carte despre perspectivele descoperirii vietii extraterestre, afirma ca, pentru moment, avem foarte putine informatii despre modul în care viata a luat nastere pe Pamânt, motiv pentru care nu suntem capabili sa recunoastem viata extraterestra.

Sursa: Discovery - via Descopera.ro

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Conform unor noi cercetari se pare ca, la toate mamiferele, creierul face acelasi lucru, indiferent daca animalele merg pe sol sau se urca într-un copac.

Creierul nu percepe spaţiul tridimensional

Oamenii de stiinta de la University College London explica faptul ca ideea conform careia oamenii concep hartile în mod tridimensional este neadevarata. Studiile lor s-au bazat pe analizarea neuronilor din zona hipocampului unor sobolani, locatie responsabila cu reprezentarea interna a spatiului. Pe masura ce animalele se deplaseaza, acesti neuroni numiti celule-grila si celule de pozitie, au un raspuns specific, activându-se si inactivându-se într-un mod ce ajuta la masurarea distantei parcurse de animal într-o anumita directie

Desi au mai existat cercetari anterioare pe aceasta tema, ele s-au concentrat pe modul în care aceste celule cartografice codifica spatiul bidimensional. Specialistii de la College London au decis sa analizeze modul în care celulele raspund la schimbarea de altitudine. Pentru a face acest lucru, ei au înregistrat impulsurile electrice de la celule individuale ale unor sobolani care urcau pe o scara spiralata. Astfel s-a observat ca ritmul de activare a celulelor a codificat foarte putine informatii legate de altitudine.

La oameni, probabil, lucrurile se petrec la fel: creierul nostru tine evidenta localizarii nostre pe o suprafata plana, definita în functie de modul în care este orientat corpul. Daca, de exemplu,o veverita se deplaseaza pe sol, iar apoi se catara într-un copac, harta sa interna bidimensionala va face trecerea de la planul orizontal la cel vertical. Astronautii sunt printre putinii oameni care pot descrie aceasta experienta. Atunci când se misca în spatiu si ajung sa "stea" pe plafon, ei au un moment de dezorientare înainte ca harta lor mentala sa se ajusteze si sa înteleaga ca punct de repet pentru "sus" este acum podeaua.

În urma studiului, cercetatorii nu reusit sa afle daca exista alte zone din creier care sunt responsabile cu codificarea altitudinii sau daca, pur si simplu, mamiferele nu au nevoie de aceasta informate pentru a trai.

"Poate un animal are harti-mozaic formate din fragmente plate, dar care pot fi orientate dupa necesitate. Sau poate, pur si simplu, creierul nostru percepe lumea ca fiind plata", a concluzionat Kathryn Jeffery, coordonatorul studiului.

Sursa: Scientific American - via Descopera.ro

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Earlier this year, juniors Eric Berdinis and Jeff Kiske, both computer engineering majors in the School of Engineering and Applied Science, hacked together a high-tech upgrade for the visually impaired out of off-the-shelf video game equipment. Called the Kinecthesia, it’s a belt-worn camera system that gives users feedback about their immediate surroundings through directional vibrations.

Although it’s fresh out of the workshop, the Kinecthesia is already generating buzz: it was selected as one of 10 projects for Google’s Zeitgeist Young Minds conference, which highlights college-aged innovators.

Berdinis and Kiske started the project as their final assignment in professor Rahul Mangharam’s embedded systems class. Tasked with creating a medical device, the duo began exploring the Microsoft Kinect, a video game controller that uses multiple cameras to translate a player’s real-life motions into actions on the screen.

“We saw that there wasn’t much in the way of assistive devices that had to do with vision, despite all of these new cameras and things like the Kinect,“ says Kiske. “We just thought it looked cool and started playing around with it.”

Recognizing the Kinect’s ability to translate details about environmental depth into digital information as a route to a high-tech upgrade on walking canes, the team began figuring out how to integrate the technology into a wearable device. Getting the cameras to talk to the BeagleBoard, a miniature, customizable computer at the heart of the system, was the first step.

 

“The Kinect wasn’t intended to work with anything but the Xbox, so modifying the code to make it work on this processor was one of the biggest challenges,” says Berdinis.

Though the Kinect is great at determining how far away objects are, another challenge was deciding how to relay that information to the user.

“We didn’t want to overwhelm the user with audio cues or vibration motors all across the waist,” says Berdinis. “Through trial and error, we found that three buzzer zones was the right amount.”

The three buzzers, positioned left, right and center, begin vibrating once objects become close enough to potentially impede the user, and increase in intensity as the objects get closer.

Berdinis and Kiske will continue to work on the Kinecthesia; connections made through the Google conference have enabled them to work with the visually impaired community and further refine their system into what could be a life-changing product.

Source: PhysOrg

More information: http://www.kinecthesia.com/

Provided by University of Pennsylvania - via ZeitNews.org

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Adolat, care provine din Uzbekistan unde viata se centreaza in jurul copiilor si a unei familii mari, a mers la medic si a aflat ca a fost sterilizata dupa ce a nascut-o pe fiica sa prin cezariana.

"Am fost socata. Am strigat si am intrebat: 'Dar de ce? Cine a putut sa faca asta?' Doctorul a spus: 'Aceasta este legea in Uzbekistan'", a declarat ea.

Cu toate acestea, sterlizarea nu este, oficial, legalizata in Uzbekistan.

Dar dovezile stranse de BBC sugereaza ca autoritatile au condus un program in ultimii doi ani pentru a steriliza femeile din tara, deseori fara stirea lor.

Femeie din Uzbekistan

"In fiecare an ni se prezinta un plan. Fiecarui doctor i se spune cator femei trebuie sa li se dea contraceptive; cate femei urmeaza sa fie sterilizate", afirma un ginecolog din capitala Taskent.

"Exista o cota. Cota mea este de patru femei pe luna", a adaugat ea sub acoperirea anonimatului.

Alte surse medicale sugereaza ca se fac presiuni puternice in special asupra medicilor din zonele rurale ale tarii, unde unii ginecologi au ordinul de a steriliza pana la opt femei pe luna.

O mama a declarat ca a avut o durere suspecta si sangerari abundente timp de mai multe luni dupa ce l-a nascut pe fiul ei. Dupa ce a facut o ecografie, a descoperit ca i-a fost scos uterul.

"Mi-au spus: 'Ce-ti mai trebuie copii? Ai deja doi'", a povestit ea.

Potrivit unei surse din cadrul Ministerului Sanatatii, programul de sterilizare are ca scop sa controleze cresterea populatiei in Uzbekistan, care a ajuns oficial la 28 de milioane de persoane.

Primul caz de sterlizare fortata a fost raportat in 2005, de Gulbakhor Turaeva, un patolog din orasul Andijan care a remarcat ca uterele unor femei tinere si sanatoase sunt aduse la morga la care lucra.

Dupa ce a strans dovezi privind 200 de sterilizari fortate, urmarind femeile ale caror utere au fost indepartate, ea si-a prezentat public descoperirile si le-a cerut explicatii sefilor sai.

Ea a fost concediata, iar in 2007 a fost incarcerata, fiind acuzata ca a introdus ilegal in tara literatura de opozitie.

Sursa: MediaFax via stirileprotv.ro

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Un'affermazione ambiziosa. " Il video più divertente di YouTube", così lo definiscono a Mountain View. E non c'è proprio da scherzare (questa passatecela), visto che c'è voluto un algoritmo degli ingegneri di Google Research per scovarlo in tutti quelli postati nella categoria Comedy. Ma come valutare quanto facesse ridere un certo video? Semplificando, è bastato un programma che prendesse in considerazione quanti " hahah" e simili fossero pubblicati nei commenti, e quante volte si usassero acronimi come " lol", " lmao", " rofl", parole come " funny" ed emoticon come " :)" o " ; - )". Senza contare, poi, le diverse enfasi che si davano ai commenti (" looooool" vale più di " lool"?). Stabiliti i parametri, i diversi video sono stati dati in pasto all'algoritmo, considerando anche la combinazione di testo e caratteristiche audiovisive. Chi ha vinto? Be', non vi resta che guardare di seguito e giudicare. E, se non vi basta, potete vedere l' intera classifica.

 

Fonte: Wired.it

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Medicii de la Spitalul general Ben Taub din Houston, Texas, testeaza efectele ketaminei asupra oamenilor care sufera de o forma severa a depresiei. Ei spun ca aceasta substanta, care are capacitatea de a amorti simturile printr-o stare de anestezie disociativa, poate înlatura starile depresive.

Tratamentul actual care este utilizat în cazul depresiei îsi face efectul în câteva saptamâni, timp în care pacientii înregistreaza tendinte de suicid. Ketamina, în schimb, îsi face efectul imediat dupa administrare.

Ketamina, remediu împotriva depresiei?

Pacientii tratati în studiu au declarat ca în primele 24 de ore de la administrarea ketaminei s-au calmat si relaxat. "Înainte, totul era în ceata. Dupa tratamentul cu ketamina am simtit ca pot începe o viata noua, sa merg acasa si sa îmi vad prietenii sau sa fac cumparaturi si sa gatesc pentru familia mea", a declarat pacienta Heather Merrill, mama a trei copii.

Daca rezultatele studiului vor fi validate, cercetatorii vor prelungi perioada de testare si vor încerca sa administreze trei doze de ketamina pe saptamâna, pentru a observa efectele pe termen lung. De asemenea, daca totul merge conform planului, ei spera sa creeze o pastila ca alternativa la tratamentul intravenos.

Ketamina poate cauza unele probleme la nivelul vezicii urinare, iar unele studii sugereaza ca ea ar putea crea probleme cardiace, putând chiar sa înrautateasca sanatatea mintala.

Sursa: Daily Mail - via Descopera.ro

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Many physicists around the world are hard at work trying to figure out new and exciting ways to create ultra-cold objects, the reason being is that if a system could be created that operates at or at least very near absolute zero, superconductors could be devised that might help create quantum computers, which would of course run at speeds that would make the current generation look quaint. Plus, theory suggests new states of matter might be discovered.

Now, new work by a group of physicists from Harvard appears to be coming closer than ever. They’ve figured out a way to remove entropy from a specialized system leaving much colder atoms behind. In their paper, published in Nature, they discuss how they’ve come up with something called an orbital excitation blockade, a form of interaction blockade, to reach temperatures tens to hundreds of times colder than current methods.

The team did their research in a three step process. In the first they shot atoms that make up rubidium with a laser, forcing them to glow in a way that made them give off more energy then they absorbed, making them cooler of course. By doing so they also created a system whereby they were able to control the atoms due to the pressure created by the laser. Thus they could hold them still, move them around, or even cause them to run into each other.

Next, the team caused the atoms to grow even colder by allowing evaporative cooling to due its work.

After that, the real work began. Here the team used meshes of lasers, called optical lattices to remove entropy from the system. The already cooled atoms were made to knock into one another using lasers ala the method used to start the whole process; this time in the optical lattices. In so doing, the excited activity of atom one dampened the excited activity of the other, a process the team calls an orbital excitation blockade. The team then removed the excited atoms from the system, leaving the unexcited, cold atoms behind, in effect, removing entropy from the system.

In actual experiments done thus, far, the team has demonstrated an ability to actually remove heat from a system using their excitation blockade, but only to a certain point. They believe more research will allow them to reach temperatures tens or even hundreds of a billionth of a degree above absolute zero, which would take them into truly unknown territory.

More information: Orbital excitation blockade and algorithmic cooling in quantum gases, Nature, 480, 500–503 (22 December 2011) doi:10.1038/nature10668

Abstract

Interaction blockade occurs when strong interactions in a confined, few-body system prevent a particle from occupying an otherwise accessible quantum state. Blockade phenomena reveal the underlying granular nature of quantum systems and allow for the detection and manipulation of the constituent particles, be they electrons, spins, atoms or photons. Applications include single-electron transistors based on electronic Coulomb blockade7 and quantum logic gates in Rydberg atoms. Here we report a form of interaction blockade that occurs when transferring ultracold atoms between orbitals in an optical lattice. We call this orbital excitation blockade (OEB). In this system, atoms at the same lattice site undergo coherent collisions described by a contact interaction whose strength depends strongly on the orbital wavefunctions of the atoms. We induce coherent orbital excitations by modulating the lattice depth, and observe staircase-like excitation behaviour as we cross the interaction-split resonances by tuning the modulation frequency. As an application of OEB, we demonstrate algorithmic cooling of quantum gases: a sequence of reversible OEB-based quantum operations isolates the entropy in one part of the system and then an irreversible step removes the entropy from the gas. This technique may make it possible to cool quantum gases to have the ultralow entropies required for quantum simulation of strongly correlated electron systems. In addition, the close analogy between OEB and dipole blockade in Rydberg atoms provides a plan for the implementation of two-quantum-bit gates in a quantum computing architecture with natural scalability.

A Harvard University press release can be found below:

Physicists at Harvard University have realized a new way to cool synthetic materials by employing a quantum algorithm to remove excess energy. The research, published this week in the journal Nature, is the first application of such an "algorithmic cooling" technique to ultra-cold atomic gases, opening new possibilities from materials science to quantum computation.

"Ultracold atoms are the coldest objects in the known universe," explains senior author Markus Greiner, associate professor of Physics at Harvard. "Their temperature is only a billionth of a degree above absolute zero temperature, but we will need to make them even colder if we are to harness their unique properties to learn about quantum mechanics."

Greiner and his colleagues study quantum many-body physics, the exotic and complex behaviors that result when simple quantum particles interact. It is these behaviors which give rise to high-temperature superconductivity and quantum magnetism, and that many physicists hope to employ in quantum computers.

"We simulate real-world materials by building synthetic counterparts composed of ultra-cold atoms trapped in laser lattices," says co-author Waseem Bakr, a graduate student in physics at Harvard. "This approach enables us to image and manipulate the individual particles in a way that has not been possible in real materials."

The catch is that observing the quantum mechanical effects that Greiner, Bakr and colleagues seek requires extreme temperatures.

"One typically thinks of the quantum world as being small," says Bakr, " but the truth is that many bizarre features of quantum mechanics, like entanglement, are equally dependent upon extreme cold."

The hotter an object is, the more its constituent particles move around, obscuring the quantum world much as a shaken camera blurs a photograph.

The push to ever-lower temperatures is driven by techniques like "laser cooling" and "evaporative cooling," which are approaching their limits at nanoKelvin temperatures. In a proof-of-principle experiment, the Harvard team has demonstrated that they can actively remove the fluctuations which constitute temperature, rather than merely waiting for hot particles to leave as in evaporative cooling.

Akin to preparing precisely one egg per dimple in a carton, this "orbital excitation blockade" process removes excess atoms from a crystal until there is precisely one atom per site.

"The collective behaviors of atoms at these temperatures remain an important open question, and the breathtaking control we now exert over individual atoms will be a powerful tool for answering it," said Greiner. "We are glimpsing a mysterious and wonderful world that has never been seen in this way before."

Source: PhysOrg - via ZeitNews.org

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Julian Assange, founder and Editor-in-Chief of WikiLeaks, has been under house arrest, without charge, for almost 500 days. Over the past two months, his temporary home in the English countryside has played host to a series of extraordinary conversations with some of the most interesting and controversial people alive in the world today. 

“The World Tomorrow” is a collection of twelve interviews featuring an eclectic range of guests, who are stamping their mark on the future: politicians, revolutionaries, intellectuals, artists and visionaries. The world's last five years have been marked by an unrelenting series of economic crises and political upheavals. But they have also given rise to the eruption of revolutionary ferment in the Middle East and to the emergence of new protest movements in the Euro-American world. In Julian's words, the aim of the show is “to capture and present some of this revolutionary spirit to a global audience. My own work with WikiLeaks hasn't exactly made my life easier”, says Assange, “but it has given us a platform to broadcast world-shifting ideas.” 

For Julian, part of the show's strength lies in its “frank and irreverent tone”. “My conviction is that power can only be transformed if it is taken seriously – but ordinary people must resist the temptation to defer to the powerful."

The original music for the show has been composed by British-Sri Lankan artist M.I.A. 

The first interview will be broadcast on RT on Tuesday 17 April, at 11:00 London time. Subsequent interviews, edited to last 26 minutes each, will be broadcast on a weekly basis. The interviews and transcripts will also be made available online. Arrangements are currently being made with other licensees to publish longer edits of the series. For more information on the show, please visit worldtomorrow.wikileaks.orghttp://worldtomorrow.wikileaks.org

FREQUENTLY ASKED QUESTIONS (FAQs) 

:: Who is producing “The World Tomorrow”? 

The show is being produced by Quick Roll Productions, a company established by Julian Assange. 
The main production partner is Dartmouth Films, a UK producer of independent films. Indispensable help and advice has been received from friends and supporters of WikiLeaks. If your network is interested in licensing the show, please visit the website of the distributor, Journeyman Pictures (http://www.journeyman.tv/63130/about-us/how-to-find-us.html). 

:: What has RT got to do with “The World Tomorrow”? 

RT is the first broadcast licensee of the show, but has not been involved in the production process. All editorial decisions have been made by Julian Assange. RT's rights encompass the first release of 26-minute edits of each episode in English, Spanish and Arabic.

:: Will the full material recorded during the interviews be made available? 

We are devoted to making available as much material as possible within the constraints of Julian's circumstances. Longer edits of the episodes will be released in due course, and transcripts of the interviews will be published on the show's independent website, worldtomorrow.wikileaks.org. (http://worldtomorrow.wikileaks.org./) 

:: Who is Julian Assange? 

Julian Assange is an Australian-born publisher, entrepreneur and internet activist. He is the Editor-in-Chief of WikiLeaks, which he founded in 2006. Since then, WikiLeaks has been responsible for releasing the biggest leaks in history, including the Afghan (http://wikileaks.org/afg/) and Iraq (http://wikileaks.org/irq/) War Logs, the Collateral Murder Video (http://collateralmurder.com/), Cablegate (http://wikileaks.org/cablegate.html) and the Global Intelligence File (http://wikileaks.org/the-gifiles.html)s. Julian and WikiLeaks have received a number of awards for journalism and campaigning, including: The Economist Award for Freedom of Expession (2008), the Amnesty International Media Award (2009), the Le Monde Person of the Year (2010), The Sydney Peace Foundation Gold Medal (2011), the Martha Gellhorn Prize for Journalism (2011) and the Walkley Award for Outstanding Contribution to Journalism (2011). He won the popular vote for TIME Person of the Year 2010. 

:: What is the current status of Julian Assange? 

As of Friday 13 April 2012, Julian has been under house arrest (http://justice4assange.com/), without charge, for 492 days. This follows on from his imprisonment in solitary confinement, also without charge, in December 2010. Julian is currently residing at a supporter's home in the English countryside, as dictated by his bail conditions. He is forced to wear an electronic manacle around his ankle at all times. Monitoring units are installed in the house and report to the British government via the security contractor, G4S (http://www.guardian.co.uk/uk/2011/mar/16/mubenga-g4s-face-charges-death). 

A closed United States Grand Jury investigation into Julian Assange has been active in the USA for 574 days. Julian is currently awaiting the result of his UK Supreme Court appeal against his extradition to Sweden (http://www.swedenversusassange.com/). Information leaked to WikiLeaks from the email accounts of US private intelligence agency Stratfor (the “shadow CIA (http://english.al-akhbar.com/content/stratfor-wanted-assange-out-any-means)”), show that the United States government issued a sealed indictment (http://wikileaks.org/Stratfor-Emails-US-Has-Issued.html) against Julian Assange as early as January 2011. 

More info: http://justice4assange.com/

:: What is the current status of WikiLeaks? 

Despite 495 days of unlawful financial blockade (http://www.wikileaks.org/Banking-Blockade.html) by a cartel made up of VISA, Mastercard, the Bank of America, Western Union and PayPal, and despite severe restrictions on the liberty of Julian Assange, WikiLeaks is continuing its operations as normal, to the best of its abilities. On Monday 27 February 2012, WikiLeaks began publishing the Global Intelligence Files (http://wikileaks.org/the-gifiles.html), over five million emails from Texas-based “global intelligence” firm Stratfor. WikiLeaks is conducting its activities in conjunction with over ninety media partners all over the globe. A number of formal actions against the banking blockade are active in Europe and South America. 

More info: http://wikileaks.org/Banking-Blockade

http://worldtomorrow.wikileaks.org/
http://justice4assange.com/
http://wikileaks.org
http://wikileaks.org/Banking-Blockade.html

Source: http://www.twitlonger.com/show/gunqv7

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I suffer from Breast Cancer, which for me, is basically a Death Sentence on my life, the thoughts of having Breast Cancer burns and itches simultaneously in my heart that i was dead alive (and looks h...
28/11/2014 @ 21:58:30
By jessica
sir are you encouraging people participate in some kind of game? ...where people give up their power? It never worked before .... that’s why I suggest instead of give up your power, exercise it from y...
05/10/2014 @ 08:45:09
By James Smith
Asta e marihoana nu?ei cine te poate opri so faci ,eu nu prefer astfel de fistractie deoarece am vazut ca dupa nu mai faci altceva fecit ca dormi bine,nu am incercat nu incerc dar nu opresc pe nimeni ...
30/09/2014 @ 09:34:56
By Miulesvu Corina Lucia
tovaraseilor .. nu confundati un sifonar sau turnator cuun ofiter sub acoperire.. e o mare diferenta ...
29/09/2014 @ 13:07:51
By Alex Andu
... deci şi Toma e securist, logic!
27/09/2014 @ 15:49:04
By Bogdan Sith Huşanu
Mai voinicilor,voi nu stiati ca inainte de 89,securistii erau omul si copacul,,ei acum sint si mai multi,cred ca au dat si lastari,ce naiba..!..
27/09/2014 @ 15:45:01
By Toma Pasculea
E greu de crezut că mişcă ceva de calibru în massmedia din orice ţară care să nu aibă vre-o treabă cu 'serviciile'. Cred că massmedia, instituţiile me...
27/09/2014 @ 15:41:52
By Alterul EgoulMeu


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