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Unprecedented Low Tornado Activity Continues: ’2012 was the slowest tornado year on record until it was beaten by 2013 – and 2014 is tied with 2013 so far’

Climate Depot - Mon, 04/21/2014 - 16:19
http://stevengoddard.wordpress.com/2014/04/21/unprecedented-low-tornado-activity-continues/

Flashback1921: Global Warming And Drought Caused Avalanches, Glacial Melt, And Snake Bites

Climate Depot - Mon, 04/21/2014 - 16:01
http://stevengoddard.wordpress.com/2014/04/21/1921-global-warming-and-drought-caused-avalanches-glacial-melt-and-snake-bites/

Flashback 1914: Royal Geographical Society: ‘Is the world drying up?’ – ‘Professor Gregory said that in recent years they had often been warned that a great climatic change was now carrying the world, slowly and irresistibly, towards world-wide drought.’

Climate Depot - Mon, 04/21/2014 - 15:34
http://stevengoddard.wordpress.com/2014/04/21/100-years-since-crack-scientists-warned-of-great-climatic-change-and-world-wide-drought/ The Mercury  Saturday 6 June 1914 Professor J. W. Gregory, F.R.S., has discussed a most interesting problem before the Royal Geographical Society—Is  the world drying up? “Professor Gregory said that in recent years they had often been warned that a great climatic change was now carrying the world, slowly and irresistibly, towards world-wide drought. [...]

Selective attention in chickens [Neuroscience]

PNAS Early Edition Articles - Mon, 04/21/2014 - 13:25
Voluntary control of attention promotes intelligent, adaptive behaviors by enabling the selective processing of information that is most relevant for making decisions. Despite extensive research on attention in primates, the capacity for selective attention in nonprimate species has never been quantified. Here we demonstrate selective attention in chickens by applying...

The evolution of self-control [Psychological and Cognitive Sciences]

PNAS Early Edition Articles - Mon, 04/21/2014 - 13:25
Cognition presents evolutionary research with one of its greatest challenges. Cognitive evolution has been explained at the proximate level by shifts in absolute and relative brain volume and at the ultimate level by differences in social and dietary complexity. However, no study has integrated the experimental and phylogenetic approach at...

Genetic cortical patterning during childhood [Psychological and Cognitive Sciences]

PNAS Early Edition Articles - Mon, 04/21/2014 - 13:25
Longitudinal imaging and quantitative genetic studies have both provided important insights into the nature of human brain development. In the present study we combine these modalities to obtain dynamic anatomical maps of the genetic contributions to cortical thickness through childhood and adolescence. A total of 1,748 anatomic MRI scans from...

Synthetic model for analysis of helix nucleation [Chemistry]

PNAS Early Edition Articles - Mon, 04/21/2014 - 13:25
Helix–coil transition theory connects observable properties of the α-helix to an ensemble of microstates and provides a foundation for analyzing secondary structure formation in proteins. Classical models account for cooperative helix formation in terms of an energetically demanding nucleation event (described by the σ constant) followed by a more facile...

Theory for plasticity of FCC metals [Applied Physical Sciences]

PNAS Early Edition Articles - Mon, 04/21/2014 - 13:25
The activation of plastic deformation mechanisms determines the mechanical behavior of crystalline materials. However, the complexity of plastic deformation and the lack of a unified theory of plasticity have seriously limited the exploration of the full capacity of metals. Current efforts to design high-strength structural materials in terms of stacking...

Suppression of cytokinin homeostasis by APETALA1 [Plant Biology]

PNAS Early Edition Articles - Mon, 04/21/2014 - 13:25
In angiosperms, after the floral transition, the inflorescence meristem produces floral meristems (FMs). Determinate growth of FMs produces flowers of a particular size and form. This determinate growth requires specification of floral organs and termination of stem-cell divisions. Establishment of the FM and specification of outer whorl organs (sepals and...

Defining functional DNA elements [Genetics]

PNAS Early Edition Articles - Mon, 04/21/2014 - 13:25
With the completion of the human genome sequence, attention turned to identifying and annotating its functional DNA elements. As a complement to genetic and comparative genomics approaches, the Encyclopedia of DNA Elements Project was launched to contribute maps of RNA transcripts, transcriptional regulator binding sites, and chromatin states in many...

Heterogeneous noradrenergic efferents to cortex [Neuroscience]

PNAS Early Edition Articles - Mon, 04/21/2014 - 13:25
The brainstem nucleus locus coeruleus (LC) is the primary source of norepinephrine (NE) to the mammalian neocortex. It is believed to operate as a homogeneous syncytium of transmitter-specific cells that regulate brain function and behavior via an extensive network of axonal projections and global transmitter-mediated modulatory influences on a diverse...

Polyphosphate accumulation in the Sargasso Sea [Earth, Atmospheric, and Planetary Sciences]

PNAS Early Edition Articles - Mon, 04/21/2014 - 13:25
Phytoplankton alter their biochemical composition according to nutrient availability, such that their bulk elemental composition varies across oceanic provinces. However, the links between plankton biochemical composition and variation in biogeochemical cycling of nutrients remain largely unknown. In a survey of phytoplankton phosphorus stress in the western North Atlantic, we found...

Heme ruffling and electron transfer in cytochromes [Chemistry]

PNAS Early Edition Articles - Mon, 04/21/2014 - 13:25
Cytochrome (cyt) c is an important electron transfer protein. The ruffling deformation of its heme cofactor has been suggested to relate to its electron transfer rate. However, there is no direct experimental evidence demonstrating this correlation. In this work, we studied Pseudomonas aeruginosa cytochrome c551 and its F7A mutant. These...

Motor cortex activation in word comprehension [Neuroscience]

PNAS Early Edition Articles - Mon, 04/21/2014 - 13:25
To address the hotly debated question of motor system involvement in language comprehension, we recorded neuromagnetic responses elicited in the human brain by unattended action-related spoken verbs and nouns and scrutinized their timecourse and neuroanatomical substrates. We found that already very early on, from ∼80 ms after disambiguation point when...

Crystal structure of GluTR-GluBP complex [Biochemistry]

PNAS Early Edition Articles - Mon, 04/21/2014 - 13:25
Tetrapyrrole biosynthesis in plants, algae, and most bacteria starts from the NADPH-dependent reduction of glutamyl-tRNA by glutamyl-tRNA reductase (GluTR). The GluTR-catalyzed reaction is the rate-limiting step, and GluTR is the target of multiple posttranslational regulations, such as heme feedback inhibition, for the tetrapyrrole biosynthetic pathway. A recently identified GluTR regulator,...
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