Fonte:
http://www.ecoblog.it/post/38441/pesticidi-nel-piatto-2012-residui-in-un-terzo-della-frutta-e-della-verdura
As sprawling housing developments and skyscrapers in one of the world's most populous countries, these tower blocks and recently-built neighbourhoods should be busy and swarming with people.
But on closer inspection these stunning pictures show elaborate public buildings and open spaces which are left completely empty.
The most recent pictures of unused housing emerged as China announced plans to build 20 cities a year for the next 20 years.
Soulless cities: Despite being unable to find buyers for the hundreds of millions of new homes, China plans to build 20 cities a year for the next 20 years
Property to let: Rows of neat, newly-built houses like these in Jiangsu are becoming more common in China
Desolate: These skyscraper in Chenggong, where there are already 100,00 new homes, should be bustling with life but are instead empty
And despite pictures last year showing some of the reported 64 million empty homes, Chinese authorities have since erected masses more buildings.
Gillem Tulloch, an aanlyst for Forensic Asia Limited, described one of the areas in Chenggong, as a 'forest of skyscrapers'.
When asked what has happened in the past six months since the ghost cities were built, he said: 'China built more of them.
'China consumes more steel, iron ore and cement per capita than any industrial nation in history.
Unused: Another vacant development in Jiangsu contains well over 100 new properties
Plenty of room spare: Experts have said some of the developments are like a 'forest of skyscrapers'
'It's all going to railways that will never make money, roads that no one drives on and cities that no one lives in.
'It's like walking into a forest of skyscrapers, but they're all empty.'
Chinese government think tank have warned that the country's real estate bubble is getting worse, with property prices in major cities overvalued by as much as 70 per cent.
Tulloch said that apartments in Chenggong, a fishing village near Hong Kong, were selling for up to $80,000.
Many of the developments like this one in Ordos, China, have swathes of newly-created public space completely unused by anyone
Zhengzhou New District residential towers: Soaring property prices in China and high levels of investment has fuelled the construction of up several new cities. Experts fear a subsequent property crash could damage the global economy
Property bubble: Zhengzhou New District features vast public buildings that have never been used
He added: 'People there were joking that no one in Denaya could afford to live there. If these apartments sell at all, it is to speculators.'
Of the 35 major cities surveyed last year, property prices in eleven including Beijing and Shanghai were between 30 and 50 per cent above their market value, the China Daily said, citing the Chinese Academy of Social Sciences.
Prices in Fuzhou, capital of the southeastern province of Fujian, had the worst property bubble with average house prices more than 70 per cent higher than their market value, according to the survey conducted in September.
The average price in the 35 cities surveyed was nearly 30 per cent above the market value, the report said.
Più di cento comuni (107), e un unico obiettivo: liberarsi dei rifiuti entro il 2020. Per cercare insieme una strategia per gestire le tonnellate di cose che, ogni giorno, vengono buttate perché non servono più. Ieri mattina, nell'auditorium di Capannori è nata l'associazione nazionale delle comunità verso Rifiuti Zero. Capannori, 46mila abitanti nel Lucchese, è stato il primo comune che, nel 2007, ha aderito alla strategia internazionale Rifiuti Zero. Oggi a Capannori la media della raccolta differenziata è all'82%, con punte di 90% nelle zone dove si applica la Tia puntuale: ogni famiglia paga per quanta indifferenziata produce.
Ora in molti credono che occorra ridurre la produzione di rifiuti all'origine. Le parole chiave, per i rappresentanti dei comuni che ieri si sono dati appuntamento e che rappresentano 3 milioni di italiani, sono differenziazione, riuso e riciclo. Le prime esperienze hanno dato buoni risultati. Per questo la Rete Italiana Rifiuti Zero, coordinata da Rossano Ercolini, e gli enti locali hanno creato un'associazione. I comuni hanno già un decalogo a cui attenersi.
Il primo passo è scommettere sulla differenziata, coinvolgendo e responsabilizzando i cittadini. In ambito casalingo, i comportamenti virtuosi sono noti: usare pannolini lavabili, dire addio alle buste di plastica, preferire l'acqua del rubinetto (che oltretutto è più sana), acquistare latte, bevande e detergenti «alla spina». Ovviamente, i virtuosi vanno poi premiati, con un sistema di tariffazione ad hoc. Altro trucco per raggiungere in poco tempo e su larga scala quote superiori al 70% è quello della raccolta porta a porta, con quattro contenitori diversi da ritirare seguendo un calendario settimanale prestabilito. Tutto questo sforzo sarebbe però inutile senza la realizzazione di un impianto di compostaggio - da collocare in aree rurali e quindi vicine ai luoghi di utilizzo da parte degli agricoltori – e di piattaforme impiantistiche per il riciclaggio e il recupero dei materiali.
Nell'ottica che niente vada sprecato, sono indispensabili anche centri per la riparazione di beni durevoli, come mobili, infissi ed elettrodomestici, da rimettere a nuovo e rivendere sul mercato: un sistema che garantisce anche ricadute positive sull'occupazione, come è già avvenuto in Australia e in Nord America. A valle della filiera, infine, servono un impianto di recupero e selezione di quei rifiuti sfuggiti alla differenziata e un centro di ricerca e riprogettazione per ripensare, su scala industriale, una nuova vita per gli oggetti non riciclabili.
THE PHYSICS ARXIV BLOG
Wednesday, October 10, 2012
One of modern physics' most cherished ideas is quantum chromodynamics, the theory that describes the strong nuclear force, how it binds quarks and gluons into protons and neutrons, how these form nuclei that themselves interact. This is the universe at its most fundamental.
So an interesting pursuit is to simulate quantum chromodynamics on a computer to see what kind of complexity arises. The promise is that simulating physics on such a fundamental level is more or less equivalent to simulating the universe itself.
There are one or two challenges of course. The physics is mind-bogglingly complex and operates on a vanishingly small scale. So even using the world's most powerful supercomputers, physicists have only managed to simulate tiny corners of the cosmos just a few femtometers across. (A femtometer is 10^-15 metres.)
That may not sound like much but the significant point is that the simulation is essentially indistinguishable from the real thing (at least as far as we understand it).
It's not hard to imagine that Moore's Law-type progress will allow physicists to simulate significantly larger regions of space. A region just a few micrometres across could encapsulate the entire workings of a human cell.
Again, the behaviour of this human cell would be indistinguishable from the real thing.
It's this kind of thinking that forces physicists to consider the possibility that our entire cosmos could be running on a vastly powerful computer. If so, is there any way we could ever know?
Today, we get an answer of sorts from Silas Beane, at the University of Bonn in Germany, and a few pals. They say there is a way to see evidence that we are being simulated, at least in certain scenarios.
First, some background. The problem with all simulations is that the laws of physics, which appear continuous, have to be superimposed onto a discrete three dimensional lattice which advances in steps of time.
The question that Beane and co ask is whether the lattice spacing imposes any kind of limitation on the physical processes we see in the universe. They examine, in particular, high energy processes, which probe smaller regions of space as they get more energetic
What they find is interesting. They say that the lattice spacing imposes a fundamental limit on the energy that particles can have. That's because nothing can exist that is smaller than the lattice itself.
So if our cosmos is merely a simulation, there ought to be a cut off in the spectrum of high energy particles.
It turns out there is exactly this kind of cut off in the energy of cosmic ray particles, a limit known as the Greisen–Zatsepin–Kuzmin or GZK cut off.
This cut-off has been well studied and comes about because high energy particles interact with the cosmic microwave background and so lose energy as they travel long distances.
But Beane and co calculate that the lattice spacing imposes some additional features on the spectrum. "The most striking feature...is that the angular distribution of the highest energy components would exhibit cubic symmetry in the rest frame of the lattice, deviating significantly from isotropy," they say.
In other words, the cosmic rays would travel preferentially along the axes of the lattice, so we wouldn't see them equally in all directions.
That's a measurement we could do now with current technology. Finding the effect would be equivalent to being able to to 'see' the orientation of lattice on which our universe is simulated.
That's cool, mind-blowing even. But the calculations by Beane and co are not without some important caveats. One problem is that the computer lattice may be constructed in an entirely different way to the one envisaged by these guys.
Another is that this effect is only measurable if the lattice cut off is the same as the GZK cut off. This occurs when the lattice spacing is about 10^-12 femtometers. If the spacing is significantly smaller than that, we'll see nothing.
Nevertheless, it's surely worth looking for, if only to rule out the possibility that we're part of a simulation of this particular kind but secretly in the hope that we'll find good evidence of our robotic overlords once and for all.
http://www.technologyreview.com/view/429561/the-measurement-that-would-reveal-the-universe-as/
Le mail ti raggiungono ovunque con BlackBerry® from Vodafone!
Nelle foto che seguono, scattate dal satellite Landsat, è possibile osservare le Bottoms Cheyenne, una delle zone umide più importanti degli Stati Uniti ubicata nel settore centrale del Kansas. Fino a poco tempo, era l'habitat ideale per circa 250 mila diverse specie di uccelli migratori che vi transitano ogni anno. Ora, lentamente, la carenza di pioggia sta trasformando le zone umide in un deserto.
La prima foto è del 18 giugno 2010 e mostra il livello medio dell'acqua durante la stagione estiva. La seconda immagine è stata scattata il 5 giugno 2011 durante un periodo di siccità moderata. La fotografia scattata poco più di un anno dopo, il 17 luglio 2012, mostra un paesaggio quasi completamente privo di acqua.
Non c'è da meravigliarsi, perché quest'anno lo stato del Kansas ha dovuto far fronte all'estate più calda e secca della sua storia. Un discorso che può essere esteso ad altri stati Americani.
Ivan GaddarI