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Westinghouse balances new and existing fleet needs

World Nuclear News - Tue, 09/20/2016 - 07:14
Two Westinghouse AP1000s are likely to start up within a year, with hot functional tests at the first-of-a-kind reactor at Sanmen in China on course to finish next month, interim president and CEO José Emeterio Gutiérrez told delegates at the World Nuclear Association's Annual Symposium held in London last week. Fuel loading at Sanmen is expected to take place before the end of the year.

Cheers! ‘Climate Hustle’ premiers on DVD as Wash Post inducts Morano into ‘Deniers Club’ – WaPo featured Morano w/ cartoon image as one of ‘worst offenders’ for ‘stalling action’

Climate Depot - Mon, 09/19/2016 - 14:28
Full WaPo ‘Deniers Club article here: https://www.washingtonpost.com/posteverything/wp/2016/09/16/deniers-club-meet-the-people-clouding-the-climate-change-debate/ WaPo: Marc Morano inducted into ‘Deniers Club’: Climate scientists “deserve to be publicly flogged.” – As a reporter for the ExxonMobil-funded Conservative News Service, Morano helped launch the swift-boat campaign attacking John F. Kerry’s military service in Vietnam. He then went to work as communications director for the leading climate change denier [...]

AT-rich DNA-associated protein controls cell fate [Microbiology]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
Faithful cell cycle progression in the dimorphic bacterium Caulobacter crescentus requires spatiotemporal regulation of gene expression and cell pole differentiation. We discovered an essential DNA-associated protein, GapR, that is required for Caulobacter growth and asymmetric division. GapR interacts with adenine and thymine (AT)-rich chromosomal loci, associates with the promoter regions...

ACOX2 deficiency: A bile acid synthesis defect [Medical Sciences]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
Acyl CoA Oxidase 2 (ACOX2) encodes branched-chain acyl-CoA oxidase, a peroxisomal enzyme believed to be involved in the metabolism of branched-chain fatty acids and bile acid intermediates. Deficiency of this enzyme has not been described previously. We report an 8-y-old male with intermittently elevated transaminase levels, liver fibrosis, mild ataxia,...

{#x201C}Molecular model of the cytokinetic node.{#x201D} [Cell Biology]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
Cytokinesis in animals, fungi, and amoebas depends on the constriction of a contractile ring built from a common set of conserved proteins. Many fundamental questions remain about how these proteins organize to generate the necessary tension for cytokinesis. Using quantitative high-speed fluorescence photoactivation localization microscopy (FPALM), we probed this question...

Cellulose synthase dynamics in secondary cell wall [Plant Biology]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
Cellulose, often touted as the most abundant biopolymer on Earth, is a critical component of the plant cell wall and is synthesized by plasma membrane-spanning cellulose synthase (CESA) enzymes, which in plants are organized into rosette-like CESA complexes (CSCs). Plants construct two types of cell walls, primary cell walls (PCWs)...

4E-BP prevents mTOR-driven cortical mislamination [Neuroscience]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
Hyperactive mammalian target of rapamycin complex 1 (mTORC1) is a shared molecular hallmark in several neurodevelopmental disorders characterized by abnormal brain cytoarchitecture. The mechanisms downstream of mTORC1 that are responsible for these defects remain unclear. We show that focally increasing mTORC1 activity during late corticogenesis leads to ectopic placement of...

T-cell receptors are localized on microvilli [Immunology and Inflammation]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
Leukocyte microvilli are flexible projections enriched with adhesion molecules. The role of these cellular projections in the ability of T cells to probe antigen-presenting cells has been elusive. In this study, we probe the spatial relation of microvilli and T-cell receptors (TCRs), the major molecules responsible for antigen recognition on...

Peptide-modified hydrogels for wound regeneration [Applied Biological Sciences]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
There is a clinical need for new, more effective treatments for chronic wounds in diabetic patients. Lack of epithelial cell migration is a hallmark of nonhealing wounds, and diabetes often involves endothelial dysfunction. Therefore, targeting re-epithelialization, which mainly involves keratinocytes, may improve therapeutic outcomes of current treatments. In this study,...

Iron partitioning in Earth{#x2019}s deep mantle [Earth, Atmospheric, and Planetary Sciences]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
We performed laser-heated diamond anvil cell experiments combined with state-of-the-art electron microanalysis (focused ion beam and aberration-corrected transmission electron microscopy) to study the distribution and valence of iron in Earth’s lower mantle as a function of depth and composition. Our data reconcile the apparently discrepant existing dataset, by clarifying the...

CNG and Cl currents in olfactory response [Neuroscience]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
Olfactory transduction in vertebrate olfactory receptor neurons (ORNs) involves primarily a cAMP-signaling cascade that leads to the opening of cyclic-nucleotide–gated (CNG), nonselective cation channels. The consequent Ca2+ influx triggers adaptation but also signal amplification, the latter by opening a Ca2+-activated Cl channel (ANO2) to elicit, unusually, an inward Cl current....

Correction to Supporting Information for Smits, Expected time-invariant effects of biological traits on mammal species duration [SI Correction]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
EVOLUTION Correction to Supporting Information for “Expected time-invariant effects of biological traits on mammal species duration,” by Peter D. Smits, which appeared in issue 42, October 20, 2015, of Proc Natl Acad Sci USA (112:13015–13020; first published October 5, 2015; 10.1073/pnas.1510482112). The authors note that Dataset S1 appeared incorrectly. The...

Kinetic advantage of rotary ATP synthase [Biophysics and Computational Biology]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
The ATP synthase (F-ATPase) is a highly complex rotary machine that synthesizes ATP, powered by a proton electrochemical gradient. Why did evolution select such an elaborate mechanism over arguably simpler alternating-access processes that can be reversed to perform ATP synthesis? We studied a systematic enumeration of alternative mechanisms, using numerical...

Structure of unliganded furin [Biochemistry]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
Proprotein convertases (PCs) are highly specific proteases required for the proteolytic modification of many secreted proteins. An unbalanced activity of these enzymes is connected to pathologies like cancer, atherosclerosis, hypercholesterolaemia, and infectious diseases. Novel protein crystallographic structures of the prototypical PC family member furin in different functional states were determined...

Correction for Liao et al., Impaired lymphatic contraction associated with immunosuppression [Corrections]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
MEDICAL SCIENCES, ENGINEERING Correction for “Impaired lymphatic contraction associated with immunosuppression,” by Shan Liao, Gang Cheng, David A. Conner, Yuhui Huang, Raju S. Kucherlapati, Lance L. Munn, Nancy H. Ruddle, Rakesh K. Jain, Dai Fukumura, and Timothy P. Padera, which appeared in issue 46, November 15, 2011, of Proc Natl...

How Sonic Hedgehog inhibits Patched [Cell Biology]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
The Hedgehog cell–cell signaling pathway is crucial for animal development, and its misregulation is implicated in numerous birth defects and cancers. In unstimulated cells, pathway activity is inhibited by the tumor suppressor membrane protein, Patched. Hedgehog signaling is triggered by the secreted Hedgehog ligand, which binds and inhibits Patched, thus...

VSMC durotaxis depends on ECM composition [Applied Physical Sciences]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
Mechanical compliance has been demonstrated to be a key determinant of cell behavior, directing processes such as spreading, migration, and differentiation. Durotaxis, directional migration from softer to more stiff regions of a substrate, has been observed for a variety of cell types. Recent stiffness mapping experiments have shown that local...

Zn2+ inhibition of a voltage-gated proton channel [Neuroscience]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
Voltage-gated proton (Hv1) channels are involved in many physiological processes, such as pH homeostasis and the innate immune response. Zn2+ is an important physiological inhibitor of Hv1. Sperm cells are quiescent in the male reproductive system due to Zn2+ inhibition of Hv1 channels, but become active once introduced into the...

LOF mutations of NF-{kappa}B pathway regulators in NPC [Genetics]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
Nasopharyngeal carcinoma (NPC) is an epithelial malignancy with a unique geographical distribution. The genomic abnormalities leading to NPC pathogenesis remain unclear. In total, 135 NPC tumors were examined to characterize the mutational landscape using whole-exome sequencing and targeted resequencing. An APOBEC cytidine deaminase mutagenesis signature was revealed in the somatic...

Ultradonut topology of the nuclear envelope [Applied Physical Sciences]

PNAS Early Edition Articles - Mon, 09/19/2016 - 13:06
The nuclear envelope is a unique topological structure formed by lipid membranes in eukaryotic cells. Unlike other membrane structures, the nuclear envelope comprises two concentric membrane shells fused at numerous sites with toroid-shaped pores that impart a “geometric” genus on the order of thousands. Despite the intriguing architecture and vital...
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