Simulated atmospheric processing of iron oxyhydroxide minerals at low pH: roles of particle size and acid anion in iron dissolution.

abstract：:In human adults, learning and memory under acute stress are characterized by an increased use of rigid habitual response strategies at the cost of flexible cognitive strategies. The immediate effects of stress on cognitive functioning early in life are not well understood. Here we show experimentally that acute stress...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Seehagen S,Schneider S,Rudolph J,Ernst S,Zmyj N

更新日期：2015-10-13 00:00:00

abstract：:A core operation in speech production is the preparation of words from a semantic base. The theory of lexical access reviewed in this article covers a sequence of processing stages beginning with the speaker's focusing on a target concept and ending with the initiation of articulation. The initial stages of preparatio...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Levelt WJ

更新日期：2001-11-06 00:00:00

abstract：:Explants of human endometrium were cultured to study the release of matrix metalloproteinases (MMPs). Analysis of conditioned media by zymography revealed latent and active forms of collagenase (MMP-1, EC 3.4.24.7), 72-kDa gelatinase A (MMP-2, EC 3.4.24.24), and 92-kDa gelatinase B (MMP-9, EC 3.4.24.35). These protein...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Marbaix E,Donnez J,Courtoy PJ,Eeckhout Y

更新日期：1992-12-15 00:00:00

abstract：:Extensive regeneration of the vertebrate body plan is found in salamander and fish species. In these organisms, regeneration takes place through reprogramming of differentiated cells, proliferation, and subsequent redifferentiation of adult tissues. Such plasticity is rarely found in adult mammalian tissues, and this ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Yun MH,Gates PB,Brockes JP

更新日期：2013-10-22 00:00:00

abstract：:Four 12-O-tetradecanoyl-13-O-acetylphorbol-type tumor promoters--teleocidin, phorbol ester, aplysiatoxin, and ingenol ester--are superposed in an attempt to understand their common biological activity on the assumption that they may bind to the same receptor site. A method using three-dimensional computer graphics was...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Itai A,Kato Y,Tomioka N,Iitaka Y,Endo Y,Hasegawa M,Shudo K,Fujiki H,Sakai S

更新日期：1988-06-01 00:00:00

abstract：:As a consequence of recent developments in molecular phylogenomics, all extant orders of placental mammals have been grouped into 3 lineages: Afrotheria, Xenarthra, and Boreotheria, which originated in Africa, South America, and Laurasia, respectively. Despite this advancement, the order of divergence of these 3 linea...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Nishihara H,Maruyama S,Okada N

更新日期：2009-03-31 00:00:00

abstract：:Ride-sharing services are transforming urban mobility by providing timely and convenient transportation to anybody, anywhere, and anytime. These services present enormous potential for positive societal impacts with respect to pollution, energy consumption, congestion, etc. Current mathematical models, however, do not...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Alonso-Mora J,Samaranayake S,Wallar A,Frazzoli E,Rus D

更新日期：2017-01-17 00:00:00

abstract：:The HLA class II-associated invariant chain (Ii)-derived peptide (CLIP) occupies the peptide binding groove during assembly in the endoplasmic reticulum, travels with HLA class II to endosomal compartments, and is subsequently released to allow binding of antigenic peptides. We investigated whether the exchange of CLI...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： van Bergen J,Schoenberger SP,Verreck F,Amons R,Offringa R,Koning F

更新日期：1997-07-08 00:00:00

abstract：:We have cloned and determined the entire nucleotide sequence of cDNAs corresponding to the putative alpha subunits of the human and rat mast cell high-affinity IgE receptors. Both human and rat cDNAs encode an NH2-terminal signal peptide, two immunoglobulin-like extracellular domains (encoded by discrete exons), a hyd...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Shimizu A,Tepler I,Benfey PN,Berenstein EH,Siraganian RP,Leder P

更新日期：1988-03-01 00:00:00

abstract：:Nuclear factor kappaB (NF-kappaB) transcription factors regulate genes responsible for critical cellular processes. IkappaBalpha, -beta, and -epsilon bind to NF-kappaBs and inhibit their transcriptional activity. The NF-kappaB-binding domains of IkappaBs contain six ankyrin repeats (ARs), which adopt a beta-hairpin/al...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Truhlar SM,Torpey JW,Komives EA

更新日期：2006-12-12 00:00:00

abstract：:Like protein enzymes, RNA enzymes (ribozymes) provide specific binding sites for their substrates. We now show that equilibrium dissociation constants for complexes between the Tetrahymena ribozyme and its RNA substrates and products can be directly measured by electrophoresis in polyacrylamide gels containing divalen...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Pyle AM,McSwiggen JA,Cech TR

更新日期：1990-11-01 00:00:00

abstract：:Activator protein-1 (AP-1) is a crucial transcription factor implicated in numerous cancers. For this reason, nine homologues of the AP-1 leucine zipper region have been characterized: Fos (c-Fos, FosB, Fra1, and Fra2), Jun (c-Jun, JunB, and JunD), and semirational library-designed winning peptides FosW and JunW. The ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Mason JM,Schmitz MA,Müller KM,Arndt KM

更新日期：2006-06-13 00:00:00

abstract：:The massive forests of central Amazonia are often considered relatively resilient against climatic variation, but this view is challenged by the wildfires invoked by recent droughts. The impact of such fires that spread from pervasive sources of ignition may reveal where forests are less likely to persist in a drier f...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Flores BM,Holmgren M,Xu C,van Nes EH,Jakovac CC,Mesquita RCG,Scheffer M

更新日期：2017-04-25 00:00:00

abstract：:pRK212.2, a derivative of the broad host range plasmid RK2, contains two EcoRI cleavage fragments, A and B, neither of which can replicate by itself in Escherichia coli. Fragment A (41.7 kilobases), but not fragment B (14.4 kilobases), can be cloned by insertion into the unrelated plasmids mini-F and ColE1. Fragment B...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Figurski DH,Helinski DR

更新日期：1979-04-01 00:00:00

abstract：:n-Type Si electrodes in MeOH solvent with 0.2 M (1-hydroxyethyl)ferrocene, 0.5 mM (1-hydroxyethyl)ferricenium, and 1.0 M LiClO(4) exhibit air mass 2 conversion efficiencies of 10.1% for optical energy into electricity. We observe open-circuit voltages of 0.53 V and short-circuit quantum efficiencies for electron flow ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Gronet CM,Lewis NS,Cogan G,Gibbons J

更新日期：1983-02-01 00:00:00

abstract：:Vanilloid receptor subunit 1 (VR1) appears to play a critical role in the transduction of noxious chemical and thermal stimuli by sensory nerve endings in peripheral tissues. Thus, VR1 antagonists are useful compounds to unravel the contribution of this receptor to pain perception, as well as to induce analgesia. We h...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： García-Martinez C,Humet M,Planells-Cases R,Gomis A,Caprini M,Viana F,De La Pena E,Sanchez-Baeza F,Carbonell T,De Felipe C,Pérez-Paya E,Belmonte C,Messeguer A,Ferrer-Montiel A

更新日期：2002-02-19 00:00:00

abstract：:The retinylidene chromophore mutant (Y185F) of bacteriorhodopsin, in which Tyr-185 is substituted by phenylalanine, is examined and compared with wild-type bacteriorhodopsin expressed in Escherichia coli; both were reinstituted similarly in vesicles. The Y185F mutant shows (at least) two distinct spectra at neutral pH...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Jang DJ,el-Sayed MA,Stern LJ,Mogi T,Khorana HG

更新日期：1990-06-01 00:00:00

abstract：:Mitochondrial dysfunctions cause numerous human disorders. A platform technology based on biodegradable polymers for carrying bioactive molecules to the mitochondrial matrix could be of enormous potential benefit in treating mitochondrial diseases. Here we report a rationally designed mitochondria-targeted polymeric n...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Marrache S,Dhar S

更新日期：2012-10-02 00:00:00

abstract：:Mitochondrial cytochrome c oxidase plays an essential role in aerobic cellular respiration, reducing dioxygen to water in a process coupled with the pumping of protons across the mitochondrial inner membrane. An aspartate residue, Asp-51, located near the enzyme surface, undergoes a redox-coupled x-ray structural chan...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Tsukihara T,Shimokata K,Katayama Y,Shimada H,Muramoto K,Aoyama H,Mochizuki M,Shinzawa-Itoh K,Yamashita E,Yao M,Ishimura Y,Yoshikawa S

更新日期：2003-12-23 00:00:00

abstract：:An expression vector containing the murine c-ets-2 protooncogene cDNA was introduced into NIH 3T3 cells by DNA transfection. The cells transfected with this construct showed foci of densely growing, morphologically altered cells, when grown either in low-serum (0.05%) or in serum-free medium. The c-ets-2-derived foci ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Seth A,Watson DK,Blair DG,Papas TS

更新日期：1989-10-01 00:00:00

abstract：:A way to assess specific CD8+ T-cell activity in a skin test analogous to the conventional delayed-type hypersensitivity (DTH) reaction for CD4+ T cells is presented. Local injection of viral class I binding peptides caused a specific CD8+ T-cell-mediated DTH in footpads of virally infected mice. The DTH was inducible...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kündig TM,Althage A,Hengartner H,Zinkernagel RM

更新日期：1992-08-15 00:00:00

abstract：:We previously identified a stromal cell-derived inducing activity (SDIA), which induces differentiation of neural cells, including midbrain tyrosine hydroxylase-positive (TH(+)) dopaminergic neurons, from mouse embryonic stem cells. We report here that SDIA induces efficient neural differentiation also in primate embr...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kawasaki H,Suemori H,Mizuseki K,Watanabe K,Urano F,Ichinose H,Haruta M,Takahashi M,Yoshikawa K,Nishikawa S,Nakatsuji N,Sasai Y

更新日期：2002-02-05 00:00:00

abstract：:We perform a generalized-ensemble simulation of a small peptide taking the interactions among all atoms into account. From this simulation we obtain thermodynamic quantities over a wide range of temperatures. In particular, we show that the folding of a small peptide is a multistage process associated with two charact...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Hansmann UH,Masuya M,Okamoto Y

更新日期：1997-09-30 00:00:00

abstract：:A descriptive medium for the presentation of protein structure has been developed and used to evaluate the structure of the active site of bovine trypsin (EC 3.4.21.4). This technique, involving advanced computer graphics technology, permits the facile display of a representation of the molecular surface of proteins o...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Feldmann RJ,Bing DH,Furie BC,Furie B

更新日期：1978-11-01 00:00:00

abstract：:Plant mortality and birth rates are critical components of plant life history affecting the stability of plant populations and the ecosystems they form. Although allometric theory predicts that both plant birth and mortality rates should be size-dependent, this prediction has not yet been tested across plants ranging ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Marbà N,Duarte CM,Agustí S

更新日期：2007-10-02 00:00:00

abstract：:Agrobacterium is a unique model system as well as a major biotechnological tool for genetic manipulation of plant cells. It is still unknown, however, whether host cellular factors exist that are limiting for infection, and whether their overexpression in plant cells can increase the efficiency of the infection. Here,...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Tzfira T,Vaidya M,Citovsky V

更新日期：2002-08-06 00:00:00

abstract：:Loss of function of CDKN2A/B, also known as INK4/ARF [encoding p16INK4A, p15INK4B, and p14ARF (mouse p19Arf)], confers susceptibility to cancers, whereas its up-regulation during organismal aging provokes cellular senescence and tissue degenerative disorders. To better understand the transcriptional regulation of p16 ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Zhang Y,Hyle J,Wright S,Shao Y,Zhao X,Zhang H,Li C

更新日期：2019-12-09 00:00:00

abstract：:We examine how the polypeptide chain in protein crystal structures exploits the multivalent hydrogen-bonding potential of bound water molecules. This shows that multiple interactions with a single water molecule tend to occur locally along the chain. A distinctive internal-coordinate representation of the local water-...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Robert CH,Ho PS

更新日期：1995-08-01 00:00:00

abstract：:Natal philopatry, the return of individuals to their natal area for reproduction, has advantages and disadvantages for animal populations. Natal philopatry may generate local genetic adaptation, but it may also increase the probability of inbreeding that can compromise persistence. Although natal philopatry is well do...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Salles OC,Pujol B,Maynard JA,Almany GR,Berumen ML,Jones GP,Saenz-Agudelo P,Srinivasan M,Thorrold SR,Planes S

更新日期：2016-11-15 00:00:00

abstract：:Using a comprehensive transcriptome analysis, a Z chromosome-linked chicken homolog of hemogen (cHEMGN) was identified and shown to be specifically involved in testis differentiation in early chicken embryos. Hemogen [Hemgn in mice, EDAG (erythroid differentiation-associated gene protein) in humans] was recently chara...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Nakata T,Ishiguro M,Aduma N,Izumi H,Kuroiwa A

更新日期：2013-02-26 00:00:00