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Fourth Ningde unit enters commercial operation

World Nuclear News - Thu, 07/21/2016 - 10:12
Unit 4 of the Ningde nuclear power plant in China's Fujian province has entered commercial operation, plant constructor China Nuclear Industry 23 Construction Company Limited announced today.

ČEZ requests EIA for new Dukovany units

World Nuclear News - Thu, 07/21/2016 - 10:00
Czech utility ČEZ has requested the Ministry of Environment carry out an environmental impact assessment (EIA) for the potential construction of two new reactors at the Dukovany nuclear power plant.

Third Barakah reactor vessel in place

World Nuclear News - Thu, 07/21/2016 - 09:56
The reactor vessel has been installed for unit 3 of the Barakah nuclear power plant under construction in the United Arab Emirates. All four units at the site should be in operation by 2020.

Significance of organic nitrates in depositions [Letters (Online Only)]

PNAS Early Edition Articles - Wed, 07/20/2016 - 13:37
It is well recognized that the NOX (NO + NO2) emission has been reduced steadily in the United States, but NH3 emission is increasing strongly without regulation. Li et al. (1) estimate the NH3 dry deposition by using the multilayer model (MLM) and bidirectional approaches, and conclude that the control...

Deposition of organic nitrogen [Letters (Online Only)]

PNAS Early Edition Articles - Wed, 07/20/2016 - 13:14
In PNAS, we (1) highlight changes in the balance of oxidized and reduced nitrogen contributions to United States reactive nitrogen deposition, pointing out that decreases in nitrogen oxides (NOx) emissions, combined with modest growth in ammonia emissions, have altered the inorganic nitrogen deposition budget from majority deposition by oxidized species...

Emergence of nontrivial excitations in spin liquid [Physics]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
When quantum fluctuations destroy underlying long-range ordered states, novel quantum states emerge. Spin-liquid (SL) states of frustrated quantum antiferromagnets, in which highly correlated spins fluctuate down to very low temperatures, are prominent examples of such quantum states. SL states often exhibit exotic physical properties, but the precise nature of the...

Regulation of CD4+ T-cell activation by CRBN [Immunology and Inflammation]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
The role of cereblon (CRBN) in T cells is not well understood. We generated mice with a deletion in Crbn and found cereblon to be an important antagonist of T-cell activation. In mice lacking CRBN, CD4+ T cells show increased activation and IL-2 production on T-cell receptor stimulation, ultimately resulting...

Spatial organization of the Ran pathway in mitosis [Biophysics and Computational Biology]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
Concentration gradients of soluble proteins are believed to be responsible for control of morphogenesis of subcellular systems, but the mechanisms that generate the spatial organization of these subcellular gradients remain poorly understood. Here, we use a newly developed multipoint fluorescence fluctuation spectroscopy technique to study the ras-related nuclear protein (Ran)...

Substrate specificity of PIPKs [Biochemistry]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
The phosphatidylinositol phosphate kinase (PIPK) family of enzymes is primarily responsible for converting singly phosphorylated phosphatidylinositol derivatives to phosphatidylinositol bisphosphates. As such, these kinases are central to many signaling and membrane trafficking processes in the eukaryotic cell. The three types of phosphatidylinositol phosphate kinases are homologous in sequence but differ...

Charge network dynamics in molecular aggregates [Chemistry]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
Due to the nonperiodic nature of charge transport in disordered systems, generating insight into static charge transport networks, as well as analyzing the network dynamics, can be challenging. Here, we apply time-dependent network analysis to scrutinize the charge transport networks of two representative molecular semiconductors: a rigid n-type molecule, perylenediimide,...

Uncalculating cooperation signals trustworthiness [Evolution]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
Humans frequently cooperate without carefully weighing the costs and benefits. As a result, people may wind up cooperating when it is not worthwhile to do so. Why risk making costly mistakes? Here, we present experimental evidence that reputation concerns provide an answer: people cooperate in an uncalculating way to signal...

Speed-dependent chemotaxis in marine bacteria [Biophysics and Computational Biology]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
Chemotaxis underpins important ecological processes in marine bacteria, from the association with primary producers to the colonization of particles and hosts. Marine bacteria often swim with a single flagellum at high speeds, alternating “runs” with either 180° reversals or ∼90° “flicks,” the latter resulting from a buckling instability of the...

P450-based cuticle resistance in malaria [Applied Biological Sciences]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
The role of cuticle changes in insecticide resistance in the major malaria vector Anopheles gambiae was assessed. The rate of internalization of 14C deltamethrin was significantly slower in a resistant strain than in a susceptible strain. Topical application of an acetone insecticide formulation to circumvent lipid-based uptake barriers decreased the...

Bunyamwera virus glycoprotein precursor processing [Microbiology]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
The M genome segment of Bunyamwera virus (BUNV)—the prototype of both the Bunyaviridae family and the Orthobunyavirus genus—encodes the glycoprotein precursor (GPC) that is proteolytically cleaved to yield two viral structural glycoproteins, Gn and Gc, and a nonstructural protein, NSm. The cleavage mechanism of orthobunyavirus GPCs and the host proteases...

Characterization of a stalled Bam complex [Biochemistry]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
The assembly of β-barrel proteins into membranes is mediated by an evolutionarily conserved machine. This process is poorly understood because no stable partially folded barrel substrates have been characterized. Here, we slowed the folding of the Escherichia coli β-barrel protein, LptD, with its lipoprotein plug, LptE. We identified a late-stage...

P450 redox partner interactions [Biophysics and Computational Biology]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
The heme iron of cytochromes P450 must be reduced to bind and activate molecular oxygen for substrate oxidation. Reducing equivalents are derived from a redox partner, which requires the formation of a protein–protein complex. A subject of increasing discussion is the role that redox partner binding plays, if any, in...

Biomimetic remodeling of lipids in membranes [Chemistry]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
Cell membranes have a vast repertoire of phospholipid species whose structures can be dynamically modified by enzymatic remodeling of acyl chains and polar head groups. Lipid remodeling plays important roles in membrane biology and dysregulation can lead to disease. Although there have been tremendous advances in creating artificial membranes to...

Cardiolipin puts the seal on ATP synthase [Commentaries]

PNAS Early Edition Articles - Wed, 07/20/2016 - 12:46
ATP synthases are remarkable proteins that regenerate the molecular fuel for cellular processes in all domains of life (1). Embedded into the inner membranes of mitochondria, chloroplasts, and bacteria, FoF1-ATP synthase produces most of the cellular ATP, using ADP and inorganic phosphate as inputs (Fig. 1A). This thermodynamically unfavorable reaction...
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