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Flachsova Monika - - 2013
We have measured the expression of 41 maternal mRNAs in individual blastomeres collected from the 8 to 32-cell Xenopus laevis embryos to determine when and how asymmetry in the body plan is introduced. We demonstrate that the asymmetry along the animal-vegetal axis in the oocyte is transferred to the daughter ...
Hu Qi-Hou - - 2013
Isoprene and monoterpenes are important precursors of secondary organic aerosols (SOA) in continents. However, their contributions to aerosols over oceans are still inconclusive. Here we analyzed SOA tracers from isoprene and monoterpenes in aerosol samples collected over oceans during the Chinese Arctic and Antarctic Research Expeditions. Combined with literature reports ...
Sun Shao-Yan - - 2013
T2DM is complex in its dynamical dependence on multiple tissues, disease states, and factors' interactions. However, most existing work devoted to characterizing its pathophysiology from one static tissue, individual factors, or single state. Here we perform a spatio-temporal analysis on T2DM by developing a new form of molecular network, i.e. ...
Eshraghi Arezoo - - 2013
Individuals with lower limb amputation need a secure suspension system for their prosthetic devices. A new coupling system was developed that is capable of suspending the prosthesis. The system's safety is ensured through an acoustic alarm system. This article explains how the system works and provides an in vivo evaluation ...
Zhou Zhao-Hua - - 2013
Polyreactive antibodies are a major component of the natural antibody repertoire and are capable of binding a variety of structurally unrelated antigens. Many of the properties attributed to natural antibodies, in fact, are turning out to be due to polyreactive antibodies. In humans, each day, billions of cells undergo apoptosis. ...
Radic Slaven - - 2013
Understanding the transformation of graphene derivatives by natural amphiphiles is essential for elucidating the biological and environmental implications of this emerging class of engineered nanomaterials. Using rapid discrete-molecular-dynamics simulations, we examined the binding of graphene and graphene oxide with peptides, fatty acids, and cellulose, and complemented our simulations by experimental ...
Lo Shun-Tsung - - 2013
We have studied a hybrid nanoelectronic system which consists of an AlGaAs/GaAs two-dimensional electron gas (2DEG) in close proximity (~70 nm) to an Al superconducting nanofilm. By tuning the current through the Al film, we can change the conductance of the 2DEG and furthermore vary the effective disorder in the Al ...
Kapadia Rehan - - 2013
III-V photovoltaics (PVs) have demonstrated the highest power conversion efficiencies for both single- and multi-junction cells. However, expensive epitaxial growth substrates, low precursor utilization rates, long growth times, and large equipment investments restrict applications to concentrated and space photovoltaics (PVs). Here, we demonstrate the first vapor-liquid-solid (VLS) growth of high-quality ...
Dou Xiaowei - - 2013
An organocatalytic conjugate addition of prochiral 3-fluorinated oxindoles to vinyl sulfones was described for the first time. In the presence of bifunctional tertiary amine-thiourea catalysts, 3-fluoro-3-substituted oxindole adducts were obtained in excellent yields and with high enantiomeric excesses.
Zhang Fenglong - - 2013
Human African trypanosomiasis (HAT) is one of the most neglected diseases in the tropic regions, which is fatal if not treated in time. There is an urgent need for new therapeutics, especially those in new chemical classes. Leucyl-tRNA synthetase (LeuRS) has been paid much attention as a recently clinically validated ...
Vignoni Mariana - - 2013
It has been well documented that β-carboline alkaloids, particularly the 9-methyl derivatives, are efficient photosensitizers. However, structure-activity relationships are missing and the photochemical mechanisms involved in the DNA photodamage still remain unknown. In the present work, we examined the capability of three 9-methyl-β-carbolines (9-methyl-norharmane, 9-methyl-harmane and 9-methyl-harmine) to induce DNA ...
Dudkin Sergii - - 2013
Reaction of 6-arylamino-1,3-dialkyluracils with anhydrides of polyfluorocarboxylic acids in the presence of pyridine and subsequent cyclization with concentrated H2SO4 gave the corresponding 1,3-dialkyl-5-(polyfluoroalkyl)pyrimido[4,5-b]quinoline-2,4(1H,3H)-diones (5-polyfluoroalkyl-5-deazaalloxazines). The reactivity of these compounds towards nucleophilic reagents, such as sodium cyanoborohydride, acetophenone, nitromethane, potassium cyanide, indole and p-thiocresol, as well as Suzuki and Sonogashira couplings ...
Lázár László - - 2013
Exo- and endocyclic double bonds of glycals and terminal double bonds of enoses were reacted with various thiols by irradiation with UV light in the presence of a cleavable photoinitiator. The photoinduced radical-mediated hydrothiolation reactions showed highly varying overall conversions depending not only on the substitution pattern and electron-density of ...
Ye Juntao - - 2013
A novel catalyst system has been indentified for addressing the long-standing issue of Z/E stereoselectivity in palladium-catalyzed exo-mode cyclization reactions of allenes bearing a nucleophilic functionality with organic halides or their equivalents. The readily accessible, sterically hindered monophosphine ligand imparts a remarkable stereocontrolling ability with broad generality under Pd catalysis.
Krishnamurthi Janagiraman - - 2013
The first catalytic asymmetric carbonyl ylide cycloaddition with arylallenes is described. With dirhodium(ii) tetrakis[N-tetrachlorophthaloyl-(S)-tert-leucinate], Rh2(S-TCPTTL)4, the cycloaddition of carbonyl ylides derived from diazoketoesters with arylallenes proceeded in a fully chemo- and regioselective manner to give highly functionalized 8-oxabicyclo[3.2.1]octanes with up to 99% ee and perfect exo diastereoselectivity.
Jennings W Brian - - 2013
A selection of imines derived from phenyl t-butyl ketones and substituted 2-phenylethylamines or phenylalanine exhibit slow rotation around the aryl-imino bond at ambient temperature, resulting in a large non-equivalence of the ortho hydrogens in the (1)H NMR spectra. This facilitates assessment of aryl substituent effects on the face tilted-T CH-π ...
Falub Claudiu V - - 2013
The fabrication of advanced devices increasingly requires materials with different properties to be combined in the form of monolithic heterostructures. In practice this means growing epitaxial semiconductor layers on substrates often greatly differing in lattice parameters and thermal expansion coefficients. With increasing layer thickness the relaxation of misfit and thermal ...
Felfly Hady - - 2013
Sprouty (Spry) genes encode negative regulators of receptor tyrosine kinase (RTK) signaling, which plays important roles in human embryonic stem cells (hESCs). SPRY2 and SPRY4 are the two most highly expressed Sprouty family members in hESCs, suggesting that they may influence self-renewal. To test this hypothesis, we performed siRNA-mediated knock ...
Rombouts Ine - - 2013
The concentration and composition of wheat gluten proteins and the presence, concentration and location of cysteine residues therein are important for wheat flour quality. However, it is difficult to identify gluten proteins, as they are an extremely polymorphic mixture of prolamins. We here present methods for cysteine labeling of wheat ...
Arce Stephen Hugo - - 2013
Detailed measurement of cell phenotype information from digital fluorescence images has the potential to greatly advance biomedicine in various disciplines such as patient diagnostics or drug screening. Yet, the complexity of cell conformations presents a major barrier preventing effective determination of cell boundaries, and introduces measurement error that propagates throughout ...
Levy Joseph S - - 2013
Thermokarst is a land surface lowered and disrupted by melting ground ice. Thermokarst is a major driver of landscape change in the Arctic, but has been considered to be a minor process in Antarctica. Here, we use ground-based and airborne LiDAR coupled with timelapse imaging and meteorological data to show ...
Ngamruengphong S - - 2013
Background and study aims: There have been concerns regarding tumor cell seeding along the needle track or within the peritoneum caused by preoperative endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). The aim of this study was to evaluate whether preoperative EUS-FNA is associated with increased risk of stomach/peritoneal recurrence and whether the ...
Law R - - 2013
Endoscopic retrograde cholangiopancreatography (ERCP) remains technically challenging following Roux-en-Y gastric bypass (RYGB). Various techniques have been described to access the excluded stomach. We describe our experience using percutaneous-assisted transprosthetic endoscopic therapy (PATENT) to perform antegrade ERCP. Balloon enteroscopy was used to access the excluded stomach. Direct retrograde percutaneous endoscopic gastrostomy ...
Rodríguez L - - 2013
Background and study aims: In patients with gastroesophageal reflux disease (GERD), temporary electrical stimulation of the lower esophageal sphincter (LES) increases LES pressure without interference with LES relaxation. The aim of the current study was to investigate the safety and efficacy of long term LES electrical stimulation therapy (LES-EST), using ...
Mori H - - 2013
Background and study aim: A reliable full-thickness suturing device is necessary for pure natural orifice transluminal endoscopic surgery (NOTES). The present study focused on assessing the reliability of a new suturing device. Methods: A total of 60 single sutures were tested to close 5-cm incisions in 8-cm square pieces of ...
Song Y - - 2013
Background and study aims: Endoscopic surgical technology has been developing rapidly. Although several successful endoscopic closure devices have already been introduced, only a few of them have demonstrated improvements in closure strength and reproducibility over conventional endoscopic clip closures or hand sutures. The objective of this study was to test ...
Qin Zhao - - 2013
The Mytilidae, generally known as marine mussels, are known to attach to most substrates including stone, wood, concrete and iron by using a network of byssus threads. Mussels are subjected to severe mechanical impacts caused by waves. However, how the network of byssus threads keeps the mussel attached in this ...
Jiang Peng - - 2013
Human pluripotent stem cells (hPSCs) have been differentiated to astroglia, but the utilization of hPSC-derived astroglia as cell therapy for neurological diseases has not been well studied. Astroglia are heterogeneous, and not all astroglia are equivalent in promoting neural repair. A prerequisite for cell therapy is to derive defined cell ...
Sayers Susan M SM Menzies School of Health Research, Darwin, NT, Australia. - - 2013
To examine the relationships between birthweight, current size, and fasting glucose and fasting insulin levels in Aboriginal adolescents. Longitudinal prospective study of a Northern Territory Aboriginal birth cohort of 686 Aboriginal babies born at the Royal Darwin Hospital between January 1987 and March 1990, and followed up between December 2006 ...
Moore P W - - 2013
Abstract Introduction. Lamotrigine is a phenyltriazine compound that inhibits voltage-gated sodium channels, decreasing release of glutamate and aspartate, and inhibits serotonin, norepinephrine and dopamine reuptake. Reports of toxicity in the literature are limited to case reports and primarily involve coingestants. This case series is intended to report the clinical manifestations ...
Jackson Deidrya A E - - 2013
Abstract Introduction. This pilot study assessed the prevalence of physiologic and behavioral adverse effects among adolescent (13-17 years) and adult (18-25 years) emergency department patients who reported energy drink and/or caffeinated-only beverage use within the 30 days prior to emergency department presentation. It was hypothesized that energy drink users would ...
An H S HS Department of Radiology, Konkuk University School of Medicine, Gwangjin-gu, Seoul, Republic of - - 2013
The aim of this study was to assess the enhancement patterns of hepatic focal nodular hyperplasia (FNH) on gadoxetic acid-enhanced MRI and diffusion-weighted (DW) MRI. This retrospective study had institutional review board approval. Gadoxetic acid-enhanced and DW MR images were evaluated in 23 patients with 30 FNHs (26 histologically proven ...
Zaman Muhammad H - - 2013
In the past decade, novel materials, probes and tools have enabled fundamental and applied cancer researchers to take a fresh look at the complex problem of tumour invasion and metastasis. These new tools, which include imaging modalities, controlled but complex in vitro culture conditions, and the ability to model and ...
Pan Shaowu - - 2013
An organic thiolate/disulfide redox couple with low absorption in the visible region was developed for use in fabricating novel dye-sensitized photovoltaic wires with an aligned carbon nanotube (CNT) fiber as the counter electrode. These flexible wire devices achieved a maximal energy conversion efficiency of 7.33%, much higher than the value ...
Sutter M E - - 2013
Abstract Background. Methamphetamine (METH) has been associated with a dilated cardiomyopathy. The first and rate-limiting step of metabolism is dependent on the polymorphic enzyme CYP2D6. Objectives. To evaluate if polymorphisms in CYP2D6 can be associated with the development of a methamphetamine-induced cardiomyopathy. Methods. We performed a prospective case-control pilot study. ...
Parsons William H - - 2013
(+)-Saxitoxin, a naturally occurring guanidinium poison, functions as a potent, selective, and reversible inhibitor of voltage-gated sodium ion channels (NaVs). Modified forms of this toxin bearing cysteine-reactive maleimide groups are available through total synthesis and are found to irreversibly inhibit sodium ion conductance in recombinantly expressed wild-type sodium channels and ...
Sattler Wesley - - 2013
The homoleptic arylisocyanide tungsten complexes, W(CNXy)6 and W(CNIph)6 (Xy = 2,6-dimethylphenyl, Iph = 2,6-diisopropylphenyl), display intense metal to ligand charge transfer (MLCT) absorptions in the visible region (400-550 nm). MLCT emission (λmax ≈ 580 nm) in tetrahydrofuran (THF) solution at rt is observed for W(CNXy)6 and W(CNIph)6 with lifetimes of ...
Iwamoto Takeaki - - 2013
An anthryl-substituted exocyclic silene, 3-silylene-2-silaaziridine, was synthesized by isomerization of the corresponding disilacyclopropanimine. The UV-vis spectrum of the silene shows a distinct intramolecular charge transfer (ICT) transition from the π orbital of the Si═C double bond to the π* orbital of the anthryl moiety. The relatively high-lying π(Si═C) orbital of ...
Sahu Sumit S Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, - - 2013
The new biomimetic ligands N4Py(2Ph) (1) and N4Py(2Ph,amide) (2) were synthesized and yield the iron(II) complexes [Fe(II)(N4Py(2Ph))(NCCH3)](BF4)2 (3) and [Fe(II)(N4Py(2Ph,amide))](BF4)2 (5). Controlled orientation of the Ph substituents in 3 leads to facile triplet spin reactivity for a putative Fe(IV)(O) intermediate, resulting in rapid arene hydroxylation. Addition of a peripheral amide ...
Blagg Robin J - - 2013
Single-molecule magnets are compounds that exhibit magnetic bistability caused by an energy barrier for the reversal of magnetization (relaxation). Lanthanide compounds are proving promising as single-molecule magnets: recent studies show that terbium phthalocyanine complexes possess large energy barriers, and dysprosium and terbium complexes bridged by an N2(3-) radical ligand exhibit ...
Killackey Eóin - - 2013
Young people who are experiencing first-episode psychosis (FEP) are at increased risk of being unemployed compared to either their same age peers in the general population, or those with other mental illnesses. Significant research has been conducted examining employment interventions for those with chronic psychotic illness. This has yielded strong ...
Carr J G - - 2013
To evaluate overall joint range of motion of the forelimb in healthy dogs ascending stairs compared with incline slope walking. Normal canine forelimb kinematics (range of motion, flexion and extension) were compared during ascent of stairs or a ramp, and compared to unimpeded trotting on a flat surface. Eight adult ...
Hunt J R - - 2013
To determine whether methadone, administered before orthopaedic surgery, results in improved postoperative analgesia compared to buprenorphine. Thirty-eight dogs undergoing orthopaedic surgeries (the majority being tibial tuberosity advancement or elbow arthrotomy) were premedicated with 0 · 03 mg/kg acepromazine and either 20 µg/kg buprenorphine or 0 · 5 mg/kg methadone, intramuscularly, allocated randomly. Anaesthesia was induced with propofol ...
Jacinto A M L - - 2013
Xanthine urolithiasis and asymptomatic xanthinuria have been diagnosed in Cavalier King Charles spaniel dogs suggesting that primary xanthinuria may be a breed-related disorder, although its prevalence remains unclear. The hypothesis of this study was that asymptomatic xanthinuria is common in Cavalier King Charles spaniel dogs. Free catch urine samples were collected ...
Garralda María A - - 2013
The dihydridoirida-β-diketone [IrH2{(PPh2(o-C6H4CO))2H}] (2) has been used as a homogeneous catalyst for the hydrolysis of ammonia- or amine-boranes to generate up to 3 equivalents of hydrogen in the presence of air. When using 0.5 mol% loading of 2, dimethylamine-borane is hydrolysed completely within 8 min at 30 °C and maintains ...
Kozinets Ekaterina M - - 2013
The reaction of [RhCl(P,S(t)Bu)(COD)] (1) or [Rh(P,S(t)Bu)(COD)]BF4 (2) where (P,S(t)Bu) is CpFe[η(5)-1,2-C5H3(PPh2)(CH2S(t)Bu)] with H2 in MeOH gives rise to COD hydrogenation and formation of a solvent-stabilized product. The formation of hydride species cannot be observed in view of a very rapid H/D exchange between H2 and the solvent. Introduction of ...
Yang Yang Y Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, - - 2013
An orthogonal set of catalyst systems has been developed for the Suzuki-Miyaura coupling of 3,3-disubstituted and 3-monosubstituted allylboronates with (hetero)aryl halides. These methods allow for the highly selective preparation of either the α- or the γ-isomeric coupling product.
DeBergh J Robb JR Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, - - 2013
A palladium-catalyzed method for the preparation of sulfonamides is described. The process exhibits significant functional group tolerance and allows for the preparation of a number of arylsulfonyl chlorides and sulfonamides under mild conditions.
Liu Wen-Bo WB Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, - - 2013
Highly congested vicinal stereocenters comprised of tertiary and all-carbon quaternary centers were generated via Ir-catalyzed asymmetric allylic alkylation of β-ketoesters. These catalytic reactions proceed in excellent yields with a broad scope on either reaction partner and with outstanding regio-, diastereo-, and enantiocontrol. Implementation of a subsequent Pd-catalyzed alkylation affords dialkylated ...
Becerra Alexandra - - 2013
Condensation of homochiral primary amines with 1-methyl-1H-imidazole-2-carbaldehyde affords the corresponding imidazolyl-imine compounds (L1-L3) which have been employed as ligands for the preparation of half-sandwich rhodium and iridium complexes of the formula [(η(5)-C5Me5)MClLn][SbF6]. Treatment of these chloride compounds with AgSbF6 renders dicationic aqua-complexes [(η(5)-C5Me5)MLn(H2O)] [SbF6]2 which act as catalysts for the ...
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