March 4th, 2006

homuncul

(no subject)

125 BIG QUESTIONS - What Don't We Know?
(Science 1 July 2005)

Science Magazine and its online companion sites celebrate the journal's 125th anniversary with a look forward -- at the most compelling puzzles and questions facing scientists today. A special, free news feature in Science explores 125 big questions that face scientific inquiry over the next quarter-century; accompanying the feature are several online extras including a reader's forum on the big questions.
http://www.sciencemag.org/sciext/125th/
homuncul

КЛАССИКА - МЕТОДОЛОГИЯ

1. Анри Пуанкаре "НАУКА И ГИПОТЕЗА"
http://vivovoco.rsl.ru/VV/PAPERS/NATURE/POINT2.HTM


2. Карл Поппер
"Логика и рост научного знания"
http://www.dr-gng.dp.ua/library/popper/pop1.htm
"Эволюционная эпистемология"
http://www.dr-gng.dp.ua/library/popper/pop2.htm


3. Pичард Фейнман "ХАРАКТЕР ФИЗИЧЕСКИХ ЗАКОНОВ"
http://vivovoco.rsl.ru/VV/Q_PROJECT/FEYNMAN/CONT.HTM
homuncul

БИОЛОГИЯ

ГЕНОМ ЧЕЛОВЕКА - International Human Genome Sequencing Cоnsortium (IHGSC)
Nature (October 2004).
http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v431/n7011/full/nature03001_fs.html


Сиквенс, по оценкам авторов, охватывает 99% of the euchromatic portion of the genome (ср. величина ошибки не превышает 1 на 100,000 base pairs) и число генов человека оценивается от 20,000 до 25,000. - Остаются не исследоваными еще 341 участок (примерно 38 million base pairs).
Результаты уточнения относятся только к т.н. 'euchromatin'-региону. Еще 20% генома остались неизученными в 'heterochromatin'-регионе - текущие методы не позволяют их секвенировать.
Прошлые данные были, тем не менее, еще менее полными.
- the draft sequences were far from perfect. Both drafts were missing some 10% of the so-called 'euchromatin' - the gene-rich portiоn of the genome - and some 30% of the genome as a whole (which includes the gene-poor regions of 'heterochromatin').

Прежние искажения объясняют несовершенством использовавшихся тогда способов дешифровки генетического кода.
“Finding the genes is hard, even in a finished sequence,” says Bob Waterstоn of the University of Washingtоn in Seattle, US, and a lead author of the latest genome analysis. “But the main point is that we have the genome correct now,” he says. “We’ve got through the many hard parts of the genome, and these included recently duplicated segments which were impossible to study in the earlier drafts.”
“Every technique has its limitatiоns, and it’s good to know what they are,” says Suttоn. “Now, we know how much to revisit and tidy up".


Сопровождающая статья Nature "Human genome: End of the beginning":
http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v431/n7011/full/431915a_fs.html

Окончание статьи:
"What is next for the human genome project? Even with a finished sequence in hand there is much still to do. Surprisingly, оne task is to develop the definitive catalogue of protein-coding genes. In the current paper, the number is estimated to be between 20,000 and 25,000. This wide range reflects limitatiоns to state-of-the-art gene-prediction software that leave doubts about the validity of many predicted genes. Оne promising approach is to use comparative genomics to align the human genome with the genomes of other animals. Because natural selection ensures that functional regions are more highly conserved than nоn-functional оnes, this approach highlights candidate protein-coding regions. The same approach shows promise for finding other functional elements such as gene promoters, which cоntrol the timing and level of expressiоn of genes, and micro-RNAs, which have been implicated as regulatory agents of many developmental processes.
Much farther in the future is the task of sequencing the remaining 20% of the genome that lies within heterochromatin, the gene-poor, highly repetitive sequence that is implicated in the processes of chromosome replicatiоn and maintenance. The repetitiveness of heterochromatin means that it cannot be tackled using current sequencing methods, and new technologies will have to be developed to attack it. So don't be shocked to see another paper announcing the 'finishing' of the human genome in 2010 - it will describe how the heterochromatin problem has been cracked.
In sequencing the human genome, researchers have already climbed mountains and travelled a long and winding road. But we are only at the end of the beginning: ahead lies another mountain range that we will need to map out and explore as we seek to understand how all the parts revealed by the genome sequence work together to make life."
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homuncul

КЛАССИКА - БИОЛОГИЯ

На столетие журнала "Nature" в 1969 году Фрэнсис Крик выступил с прогнозом развития молекулярной биологии на 30 лет вперед.
Мэтр практически не ошибся.

Фрэнсис Крик "Молекулярная биология в 2000 году"
http://vivovoco.rsl.ru/VV/PAPERS/NATURE/CRICK/CRICK_F.HTM


Комментарии прогноза Крика с высоты современных знаний
http://vivovoco.rsl.ru/VV/PAPERS/NATURE/CRICK/CRICK_A.HTM
homuncul

ФИЗИКА

1. Обзор Нобелевского лауреата Стивена Вайнберга (Steven Weinberg):
"ЕДИНАЯ ФИЗИКА к 2050 ?"

Будущие эксперименты в CERN и в других лабораториях должны позволить нам завершить Стандартную Модель физики элементарных частиц, но такая объединенная теория всех сил, вероятно, будет требовать радикально новых идей.

http://www.scientific.ru/journal/weinberg/weinberg.html (русский)
http://www.sciam.com/1999/1299issue/1299weinberg.html (english)



2. Обзор Нобелевского лауреата В. Л. Гинзбурга (в 2-х частях):
"КАКИЕ ПРОБЛЕМЫ ФИЗИКИ И АСТРОФИЗИКИ ПРЕДСТАВЛЯЮТСЯ СЕЙЧАС, НА ПОРОГЕ ХХI ВЕКА, ОСОБЕННО ВАЖНЫМИ И ИНТЕРЕСНЫМИ?"
http://nauka.relis.ru/cgi/nauka.pl?05+9911+05911014+HTML
http://nauka.relis.ru/cgi/nauka.pl?05+9912+05912018+html
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homuncul

Neuroscience

птичий мозг хотят поднять в статусе и приравнять к маммальному...


Duke University
(Nature Reviews Neuroscience)
An international consortium of 29 neuroscientists has proposed a drastic renaming of the structures of the bird brain to correctly portray birds as more comparable to mammals in their cognitive ability. The scientists assert that the century-old traditional nomenclature is outdated and does not reflect new molecular, genetic and behavioral studies that reveal the brainpower of birds.

We believe that names have a powerful influence on the experiments we do and the way in which we think," wrote the consortium members in their paper. "For this reason, and in the light of new evidence about the function and evolution of the vertebrate brain, the international consortium of neuroscientists has reconsidered the traditional 100-year-old terminology that is used to describe the avian cerebrum.

"We have to get rid of the idea that mammals -- and humans in particular -- are the pinnacle of evolution. We have to stop using words like 'lower vertebrates' and 'higher vertebrates.' We also have to understand that evolution is not linear, but an intricate branching process. So, we can't automatically expect to track a structure in the human brain back to other current vertebrate species."

According to Jarvis, new research "debunks the theory that the brain evolved in stages, like the laying down of geological sediments layer by layer. There is no evidence to show that there was a primordial brain structure to which so-called higher brain structures were systematically added."

In the Nature Reviews Neuroscience paper, the authors described studies by other researchers and their own studies demonstrating that the so-called "primitive" regions of avian brains were actually sophisticated processing regions homologous to those in mammals.

Full review: http://news.mc.duke.edu/news/article.php?id=8401


Meet Erich Jarvis
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homuncul

КЛАССИКА - NEUROSCIENCE

Фрэнсис Крик - это голова...


Статья 1979 г. ничуть не потеряла своей актуальности
Ф.Крик "Мысли о мозге"
http://www.scorcher.ru/neuro/science/base/mem11.htm


Тот номер "Scientific American" был целиком посвящен Мозгу.
http://www.scorcher.ru/neuro/science/base/brain.htm
homuncul

NEUROSCIENCE

"The Mentality of Crows: Convergent Evolution of Intelligence in Corvids and Apes"
Science, December 2004
http://www.sciencemag.org/cgi/content/abstract/306/5703/1903

Discussions of the evolution of intelligence have focused on monkeys and apes because of their close evolutionary relationship to humans. Other large-brained social animals, such as corvids, also understand their physical and social worlds. Here we review recent studies of tool manufacture, mental time travel, and social cognition in corvids, and suggest that complex cognition depends on a "tool kit" consisting of causal reasoning, flexibility, imagination, and prospection. Because corvids and apes share these cognitive tools, we argue that complex cognitive abilities evolved multiple times in distantly related species with vastly different brain structures in order to solve similar socioecological problems.


Crow manufactures tool - amazing!!
Oxford video (quicktime) 1,25 Mb
http://users.ox.ac.uk/~kgroup/trial7_web.mov