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Cheers! EPA administrator Scott Pruitt did not mention climate change once in his first speech to the EPA

Climate Depot - Tue, 02/21/2017 - 15:09
EPA administrator Scott Pruitt did not mention climate change once in his first speech to the EPA https://thinkprogress.org/pruitt-epa-speech-climate-change-public-health-41717efee746?source=rss—-e5293acf313e—4 Pruitt has consistently questioned the established science on climate change.Environmental Protection Agency (EPA) Administrator Scott Pruitt holds up a hat that was presented to him before speaking to employees of the EPA in Washington, Tuesday, Feb. 21, 2017. [...]

Methane bomb (scare) bursts: catastrophic release of methane highly unlikely

Climate Depot - Tue, 02/21/2017 - 14:12
By Thomas Richard A new USGS report challenges the consensus belief that a warming climate would lead to an explosive release of methane into the atmosphere from the breakdown of frozen methane hydrates. Climate alarmists like Al Gore have called this the ‘methane bomb,’ where frozen hydrates stored beneath the permafrost and seabed floors warms [...]

Designing allostery-inspired response in mechanical networks [Physics]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Recent advances in designing metamaterials have demonstrated that global mechanical properties of disordered spring networks can be tuned by selectively modifying only a small subset of bonds. Here, using a computationally efficient approach, we extend this idea to tune more general properties of networks. With nearly complete success, we are...

Giant ripples on comet 67P/Churyumov-Gerasimenko sculpted by sunset thermal wind [Physics]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Explaining the unexpected presence of dune-like patterns at the surface of the comet 67P/Churyumov–Gerasimenko requires conceptual and quantitative advances in the understanding of surface and outgassing processes. We show here that vapor flow emitted by the comet around its perihelion spreads laterally in a surface layer, due to the strong...

Social-ecological network analysis of scale mismatches in estuary watershed restoration [Sustainability Science]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Resource management boundaries seldom align with environmental systems, which can lead to social and ecological problems. Mapping and analyzing how resource management organizations in different areas collaborate can provide vital information to help overcome such misalignment. Few quantitative approaches exist, however, to analyze social collaborations alongside environmental patterns, especially among...

Differential TOR activation and cell proliferation in Arabidopsis root and shoot apexes [Plant Biology]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
The developmental plasticity of plants relies on the remarkable ability of the meristems to integrate nutrient and energy availability with environmental signals. Meristems in root and shoot apexes share highly similar molecular players but are spatially separated by soil. Whether and how these two meristematic tissues have differential activation requirements...

Real space renormalization group theory of disordered models of glasses [Applied Physical Sciences]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
We develop a real space renormalization group analysis of disordered models of glasses, in particular of the spin models at the origin of the random first-order transition theory. We find three fixed points, respectively, associated with the liquid state, with the critical behavior, and with the glass state. The latter...

Identification of productive and futile encounters in an electron transfer protein complex [Biophysics and Computational Biology]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Well-defined, stereospecific states in protein complexes are often in exchange with an ensemble of more dynamic orientations: the encounter states. The structure of the stereospecific complex between cytochrome P450cam and putidaredoxin was solved recently by X-ray diffraction as well as paramagnetic NMR spectroscopy. Other than the stereospecific complex, the NMR...

Generalized myoclonic epilepsy with photosensitivity in juvenile dogs caused by a defective DIRAS family GTPase 1 [Genetics]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
The clinical and electroencephalographic features of a canine generalized myoclonic epilepsy with photosensitivity and onset in young Rhodesian Ridgeback dogs (6 wk to 18 mo) are described. A fully penetrant recessive 4-bp deletion was identified in the DIRAS family GTPase 1 (DIRAS1) gene with an altered expression pattern of DIRAS1...

Hypermutation signature reveals a slippage and realignment model of translesion synthesis by Rev3 polymerase in cisplatin-treated yeast [Genetics]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Gene–gene or gene–drug interactions are typically quantified using fitness as a readout because the data are continuous and easily measured in high throughput. However, to what extent fitness captures the range of other phenotypes that show synergistic effects is usually unknown. Using Saccharomyces cerevisiae and focusing on a matrix of...

Ancient X chromosomes reveal contrasting sex bias in Neolithic and Bronze Age Eurasian migrations [Anthropology]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Dramatic events in human prehistory, such as the spread of agriculture to Europe from Anatolia and the late Neolithic/Bronze Age migration from the Pontic-Caspian Steppe, can be investigated using patterns of genetic variation among the people who lived in those times. In particular, studies of differing female and male demographic...

Inhibition of {alpha}9{alpha}10 nicotinic acetylcholine receptors prevents chemotherapy-induced neuropathic pain [Biochemistry]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Opioids are first-line drugs for moderate to severe acute pain and cancer pain. However, these medications are associated with severe side effects, and whether they are efficacious in treatment of chronic nonmalignant pain remains controversial. Medications that act through alternative molecular mechanisms are critically needed. Antagonists of α9α10 nicotinic acetylcholine...

Nondestructive nanostraw intracellular sampling for longitudinal cell monitoring [Cell Biology]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Here, we report a method for time-resolved, longitudinal extraction and quantitative measurement of intracellular proteins and mRNA from a variety of cell types. Cytosolic contents were repeatedly sampled from the same cell or population of cells for more than 5 d through a cell-culture substrate, incorporating hollow 150-nm-diameter nanostraws (NS)...

Conformational dynamics of a neurotransmitter:sodium symporter in a lipid bilayer [Biochemistry]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Neurotransmitter:sodium symporters (NSSs) are integral membrane proteins responsible for the sodium-dependent reuptake of small-molecule neurotransmitters from the synaptic cleft. The symporters for the biogenic amines serotonin (SERT), dopamine (DAT), and norepinephrine (NET) are targets of multiple psychoactive agents, and their dysfunction has been implicated in numerous neuropsychiatric ailments. LeuT, a...

Rps3/uS3 promotes mRNA binding at the 40S ribosome entry channel and stabilizes preinitiation complexes at start codons [Biochemistry]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
The eukaryotic 43S preinitiation complex (PIC) bearing Met-tRNAiMet in a ternary complex (TC) with eukaryotic initiation factor (eIF)2-GTP scans the mRNA leader for an AUG codon in favorable “Kozak” context. AUG recognition provokes rearrangement from an open PIC conformation with TC bound in a state not fully engaged with the...

Distinct conformations of GPCR-{beta}-arrestin complexes mediate desensitization, signaling, and endocytosis [Biophysics and Computational Biology]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
β-Arrestins (βarrs) interact with G protein-coupled receptors (GPCRs) to desensitize G protein signaling, to initiate signaling on their own, and to mediate receptor endocytosis. Prior structural studies have revealed two unique conformations of GPCR–βarr complexes: the “tail” conformation, with βarr primarily coupled to the phosphorylated GPCR C-terminal tail, and the...

Targeting human Mas-related G protein-coupled receptor X1 to inhibit persistent pain [Neuroscience]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Human Mas-related G protein-coupled receptor X1 (MRGPRX1) is a promising target for pain inhibition, mainly because of its restricted expression in nociceptors within the peripheral nervous system. However, constrained by species differences across Mrgprs, drug candidates that activate MRGPRX1 do not activate rodent receptors, leaving no responsive animal model to...

Heart failure drug changes the mechanoenzymology of the cardiac myosin powerstroke [Biochemistry]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Omecamtiv mecarbil (OM), a putative heart failure therapeutic, increases cardiac contractility. We hypothesize that it does this by changing the structural kinetics of the myosin powerstroke. We tested this directly by performing transient time-resolved FRET on a ventricular cardiac myosin biosensor. Our results demonstrate that OM stabilizes myosin’s prepowerstroke structural...

Integrated view of internal friction in unfolded proteins from single-molecule FRET, contact quenching, theory, and simulations [Biophysics and Computational Biology]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Internal friction is an important contribution to protein dynamics at all stages along the folding reaction. Even in unfolded and intrinsically disordered proteins, internal friction has a large influence, as demonstrated with several experimental techniques and in simulations. However, these methods probe different facets of internal friction and have been...

Robust sampling of decision information during perceptual choice [Psychological and Cognitive Sciences]

PNAS Early Edition Articles - Tue, 02/21/2017 - 12:14
Humans move their eyes to gather information about the visual world. However, saccadic sampling has largely been explored in paradigms that involve searching for a lone target in a cluttered array or natural scene. Here, we investigated the policy that humans use to overtly sample information in a perceptual decision...
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