{"id":32916,"date":"2017-11-23T14:00:51","date_gmt":"2017-11-23T13:00:51","guid":{"rendered":"https:\/\/ocasapiens-dweb.blogautore.repubblica.it\/?p=32916"},"modified":"2017-11-23T14:00:51","modified_gmt":"2017-11-23T13:00:51","slug":"reattori-celesti-os-digest","status":"publish","type":"post","link":"https:\/\/archivio.ocasapiens.org\/index.php\/2017\/11\/23\/reattori-celesti-os-digest\/","title":{"rendered":"Reattori celesti (O's digest)"},"content":{"rendered":"

Su Nature<\/em>, un paio di paper potrebbero piacere ad Andrea Idini, “Solar abundance ratios of the iron-peak elements<\/a>“, sui metalli prodotti dalla nucleosintesi stellare nell’ammasso di Perseo:<\/p>\n

Comparison between our results and modern nucleosynthesis calculations\u00a0disfavours the hypothesis that type Ia supernova progenitors are exclusively white dwarfs with masses well below the Chandrasekhar limit (about 1.4 times the mass of the Sun).<\/p>\n

della Collaborazione Hitomi<\/a> (il satellite per l’astronomia nei raggi X che s’\u00e8 rotto <\/span><\/a><\/span>un mese dopo il lancio) che era stato anticipato on line (com. stampa<\/span><\/a><\/span>). E, pi\u00f9 sorprendente per me almeno, “Photonuclear reactions triggered by lightning discharge<\/a>” di Teruaki Enoto dell’universit\u00e0 di Kyoto un altro gruppo di fisici giapponesi:<\/p>\n

Lightning and thunderclouds are natural particle accelerators. […]\u00a0During a thunderstorm on 6 February 2017 in Japan, a gamma-ray flash with a duration of less than one millisecond was detected at our monitoring sites 0.5\u20131.7 kilometres away from the lightning. The subsequent gamma-ray afterglow subsided quickly, with an exponential decay constant of 40\u201360 milliseconds, and was followed by prolonged line emission at about 0.511 megaelectronvolts, which lasted for a minute.<\/p>\n

Il lampo gamma \u00e8 durato niente, ma la sua scia quasi un minuto. Nel frattempo elettroni schizzavano nelle nubi, disintegrazione a gogo di azoto-14 e ossigeno-16, produzione di carbonio-14, antimateria e annichilazioni:<\/p>\n

The observed decay timescale and spectral cutoff at about 10 megaelectronvolts of the gamma-ray afterglow are well explained by de-excitation gamma-rays from nuclei excited by neutron capture. The centre energy of the prolonged line emission corresponds to electron\u2013positron annihilation, providing conclusive evidence of positrons being produced after the lightning.<\/p>\n

Era previsto da prima che si sapessero quali particelle cercare, spiega Leonid Babich<\/span><\/a><\/span>.
\nNelle news, due articoli da collegare. Nicky Phillips <\/span><\/a><\/span>parla di un software che rivela errori nelle sequenze genetiche pubblicate:<\/p>\n

Two scientists […] have used it to identify flaws in more than 60 papers, almost all of them studies of cancer.<\/p>\n

Jennifer Byrne, a cancer researcher at the Kids Research Institute of the Children\u2019s Hospital at Westmead in Sydney, Australia, and Cyril Labb\u00e9, a computer scientist at the University of Grenoble Alpes in Grenoble, France, made public an early version of the program, called\u00a0Seek & Blastn<\/a>, in October and now they want other researchers to test the program and help to improve it. They then plan to offer it to journal editors and publishers as an addition to the tools that most already use to check papers, such as software to detect plagiarism.<\/p>\n

In un bel saggio di storia e sociologia della genetica, Elie Dolgin riassume<\/span><\/a><\/span> le scoperte di\u00a0Peter Kerpedjiev et al. sui geni pi\u00f9 popolari e di moda nella ricerca. Vince il TP53<\/em> e la sua proteina<\/p>\n

On average, around two papers are published each day describing new details of the basic biology of\u00a0TP53<\/i>.\u00a0Its popularity shouldn\u2019t come as news to most biologists. The gene is a tumour suppressor, and widely known as the \u2018guardian of the genome\u2019. […]<\/p>\n

Ci sono tanti buoni motivi per le preferenze e per le “mode”, la diffusione dell’AIDS per esempio, ma creano un problema:<\/p>\n

Out of the 20,000 or so protein-coding genes in the human genome, just 100 account for more than one-quarter of the papers tagged by the NLM. Thousands go unstudied in any given year.<\/p>\n

Nelle ricerche sui geni di altri animali, il topo batte l’amata moscerina della frutta…<\/p>\n

*<\/p>\n

Alle Ong che si occupano di fame nel mondo, seguono i vertici sul clima, gli scopi dello sviluppo sostenibile ecc., segnalo il modello di Frances Moore et al.<\/span><\/a><\/span> sul costo del carbonio per l’agricoltura e la “damage function” dei cambiamenti climatici per i contadini, in particolare nei paesi poveri, uscito su Nature Communications<\/em>. Che io sappia\u00a0 \u00e8 il primo del suo genere, rientra nelle ricerche di attribuzione, ma anche nella discussione su se e come assicurare i raccolti, insomma mi sembra interessante. Se riusciamo,<\/del> ne parliamo domani a radiopop.
\nSempre su Nature Communications<\/em>, Christian Pfrang dell’universit\u00e0 di Reading et al. identificano<\/span><\/a><\/span>\u00a0una geoignegneria culinaria che ha il potenziale di raffreddare il clima: i fumi dell’olio da frittura… Dal com. stampa<\/span><\/a><\/span>:<\/p>\n

Dr Squires, Associate Professor of Biophysics and Materials at the University of Bath, said:\u00a0\u201cWe know that the complex structures we saw are formed by similar fatty acid molecules like soap in water. There, they dramatically affect whether the mixture is cloudy or transparent, solid or liquid, and how much it absorbs moisture from the atmosphere in a lab. The idea that this may also be happening in the air above our heads is exciting, and raises challenges in understanding what these cooking fats are really doing to the world around us.\u201d<\/p>\n

Non parliamo della sfida per la salute.
\nLe emissioni di CO2 in Cina sono calate tra il 2007 e il 2012, scrivono Zhifu Mi et al<\/span>.<\/a>, perch\u00e9 le ha esportate nei paesi poveri:<\/p>\n

Here we show that emission flow patterns have changed greatly in both domestic and foreign trade since the financial crisis. Some economically less developed regions, such as Southwest China, have shifted from being a net emission exporter to being a net emission importer. In terms of foreign trade, emissions embodied in China\u2019s exports declined from 2007 to 2012 mainly due to changes in production structure and efficiency gains, while developing countries became the major destination of China\u2019s export emissions.<\/p>\n

Uno studio<\/span><\/a><\/span>, di ricercatori coreani questa volta, conferma che il ciclo del carbonio \u00e8 intensificato dal Ni\u00f1o e fa alcune proiezioni:<\/p>\n

We show herein that the sensitivity of the terrestrial carbon flux to ENSO will be enhanced under greenhouse warming by 44% (\u00b1 15%), indicating a future amplification of carbon\u2013climate interactions.<\/p>\n","protected":false},"excerpt":{"rendered":"

Su Nature, un paio di paper potrebbero piacere ad Andrea Idini, “Solar abundance ratios of the iron-peak elements“, sui metalli prodotti dalla nucleosintesi stellare nell’ammasso di Perseo: Comparison between our results and modern nucleosynthesis calculations\u00a0disfavours the hypothesis that type Ia supernova progenitors are exclusively white dwarfs with masses well below the Chandrasekhar limit (about 1.4… Continua a leggere Reattori celesti (O's digest)<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5,10,16,17],"tags":[214,2937,4563,4725,4894,5768],"class_list":["post-32916","post","type-post","status-publish","format-standard","hentry","category-astronomia","category-clima","category-fisica","category-genetica","tag-agricoltura","tag-geni-di-moda","tag-modelli","tag-nature","tag-nucleosintesi-stellare","tag-reazioni-fotonucleari","entry"],"_links":{"self":[{"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/posts\/32916","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/comments?post=32916"}],"version-history":[{"count":0,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/posts\/32916\/revisions"}],"wp:attachment":[{"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/media?parent=32916"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/categories?post=32916"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archivio.ocasapiens.org\/index.php\/wp-json\/wp\/v2\/tags?post=32916"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}