bluuebunny/crossref_metadata_2025 huggingface dataset:
Observed evidence of the anomalous South China Sea western boundary current during the summers of 2010 and 2011
Authors: Shu Yeqiang , Xue Huijie , Wang Dongxiao , Xie Qiang , Chen Ju , Li Jian , Chen Rongyu , He Yunkai , Li Daning
Published: January 2016

Seven years of directly measured current data from a mooring in the Xisha area of the South China Sea (SCS), together with shipboard ADCP and satellite data, have shown the western boundary current (WBC) anomaly and its vertical structure during the summers of 2010 and 2011. The observed WBC presented obvious year‐to‐year variability, especially in the summer. Overall, the summer mean velocity at the mooring site over 7‐year (2007–2013) was northeastward. The moored ADCP showed that the northeastward velocity was particularly strong in the summer of 2010, but the increase was confined in the upper 120 m. In contrast, the northeastward current disappeared throughout the observed depth range (from 50 to 450 m) in the summer of 2011. Even at the deepest observed position, the monthly velocity anomalies reached 14 cm s−1 westward and 12 cm s−1 southward in the zonal and meridional directions, respectively. Both the Vietnam offshore current (VOC) and double gyres in the western SCS disappeared and the southern anticyclonic gyre expanded to strengthened the northward WBC in the summer of 2010. However, in summer of 2011, the VOC intensified, and the northern cyclonic gyre enlarged with its northern edge reaching 18°N, slightly north of mooring site, which weakened the northeastward WBC. The observed SCS circulation anomalies during 2010 and 2011 were mainly induced by the basin‐scale wind field anomalies associated with the 2009/2010 El Niño and 2010/2011 La Niña.
High‐resolution NU‐WRF simulations of a deep convective‐precipitation system during MC3E: Further improvements and comparisons between Goddard microphysics schemes and observations
Authors: Tao Wei‐Kuo , Wu Di , Lang Stephen , Chern Jiun‐Dar , Peters‐Lidard Christa , Fridlind Ann , Matsui Toshihisa
Published: January 2016

The Goddard microphysics was recently improved by adding a fourth ice class (frozen drops/hail). This new 4ICE scheme was developed and tested in the Goddard Cumulus Ensemble (GCE) model for an intense continental squall line and a moderate, less organized continental case. Simulated peak radar reflectivity profiles were improved in intensity and shape for both cases, as were the overall reflectivity probability distributions versus observations. In this study, the new Goddard 4ICE scheme is implemented into the regional‐scale NASA Unified‐Weather Research and Forecasting (NU‐WRF) model, modified and evaluated for the same intense squall line, which occurred during the Midlatitude Continental Convective Clouds Experiment (MC3E). NU‐WRF simulated radar reflectivities, total rainfall, propagation, and convective system structures using the 4ICE scheme modified herein agree as well as or significantly better with observations than the original 4ICE and two previous 3ICE (graupel or hail) versions of the Goddard microphysics. With the modified 4ICE, the bin microphysics‐based rain evaporation correction improves propagation and in conjunction with eliminating the unrealistic dry collection of ice/snow by hail can replicate the erect, narrow, and intense convective cores. Revisions to the ice supersaturation, ice number concentration formula, and snow size mapping, including a new snow breakup effect, allow the modified 4ICE to produce a stronger, better organized system, more snow, and mimic the strong aggregation signature in the radar distributions. NU‐WRF original 4ICE simulated radar reflectivity distributions are consistent with and generally superior to those using the GCE due to the less restrictive domain and lateral boundaries.
Robust boundary stabilization of a vibrating rectangular plate using disturbance adaptation
Authors: Tavasoli Ali
Published: January 2016

This paper considers robust boundary control with disturbance adaptation to stabilize the vibration of a rectangular plate under disturbances with unknown upper‐bounds. Disturbances are considered to be distributed both over the plate interior domain and along the boundary (in‐domain and boundary distributed disturbances). Applying Hamilton's principle, the dynamics of the plate is represented in the form of a fourth‐order partial differential equation subject to static and dynamic boundary conditions. The proposed model considers the membrane effect of axial force and the effect of actuator mass dynamics on the plate vibration. A robust boundary control is established that stabilizes the plate in presence of both in‐domain and boundary disturbances. A rigorous Lyapunov stability analysis shows that the vibration of the plate is uniformly ultimately bounded and converges to the vicinity of zero by proper selection of control gains. For the vanishing in‐domain disturbances, it is seen that exponential stability is achieved by the proposed control. Next, a disturbance adaptation law is introduced to stabilize the plate vibration in response to disturbances with unknown bounds, and the stability of the robust boundary control with disturbance adaptation is studied using Lyapunov. Simulation results verify the efficiency of the suggested control. Copyright © 2016 John Wiley & Sons, Ltd.
Mobility Enhancement in Solution‐Processed Transparent Conductive Oxide TFTs due to Electron Donation from Traps in High‐k Gate Dielectrics
Authors: Zeumault Andre , Subramanian Vivek
Published: January 2016

High‐mobility ZnO thin films are deposited onto solution‐processed ZrO2 dielectrics in order to investigate the large differences between experimental field‐effect mobility values obtained when transparent conductive oxide (TCO) materials are deposited onto high‐k dielectrics as opposed to thermally grown SiO2. Through detailed electrical characterization, the mobility enhancement in ZnO is correlated to the presence of electron traps in ZrO2 serving to provide an additional source of electrons to the ZnO. Furthermore, as a consequence of the general tendency for solution‐processed high‐k dielectrics to exhibit similar behavior, the broad applicability is suggested to other TCO/high‐k material combinations in agreement with experimental observations.
Catalytic One‐Pot Oxetane to Carbamate Conversions: Formal Synthesis of Drug Relevant Molecules
Authors: Guo Wusheng , Laserna Victor , Rintjema Jeroen , Kleij Arjan W.
Published: January 2016

Oxetanes are versatile building blocks in drug‐related synthesis to induce property‐modulating effects. Whereas related oxiranes are widely used in coupling chemistry with carbon dioxide (CO2) to afford value‐added commodity chemicals, oxetane/CO2 couplings remain extremely limited despite the recent advances in the synthesis of these four‐membered heterocycles. Here we report an effective one‐pot three‐component reaction (3CR) strategy for the coupling of (substituted) oxetanes, amines and CO2 to afford a variety of functionalized carbamates with excellent chemoselectivity and good yields. The process is mediated by an aluminium‐based catalyst under relatively mild conditions and the developed catalytic methodology can be applied to the formal synthesis of two pharmaceutically relevant carbamates with the 3CR being a key step.

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Ultrasonically enhanced bulk ATRP of methyl methacrylate at high conversion with good livingness and control
Authors: Rabea Ali Mohammad , Zhu Shiping
Published: January 2016

A great challenge in controlled radical polymerization such as atom transfer radical polymerization (ATRP) has been related to keep the livingness and molecular weight control of the reaction at high conversion, especially in bulk polymerization. The objective of this work is to investigate the effects of ultrasound power on the polymerization at high conversion. The initiator for continuous activator regeneration ATRP is used for bulk polymerization of methyl methacrylate (MMA) as the model system. Good livingness and control up to high conversion are obtained through employing ultrasonic waves. By this method, MMA is polymerized in bulk up to “glass state” (88%) at 70°C with polydispersity about 1.2 under an operating frequency of 40 kHz and output power of 100 W. Chain extension reaction proves the livingness of the synthesized polymers at glassy state. © 2016 American Institute of Chemical Engineers AIChE J, 62: 1683–1687, 2016
Multiple copy number variants in a pediatric patient with Hb H disease and intellectual disability
Authors: Scheps Karen G. , Francipane Liliana , Nevado Julián , Basack Nora , Attie Myriam , Bergonzi María Fernanda , Cerrone Gloria E. , Lapunzina Pablo , Varela Viviana
Published: January 2016

Two distinct syndromes that link α‐thalassemia and intellectual disability (ID) have been described: ATR‐X, due to mutations in the ATRX gene, and ATR‐16, a contiguous gene deletion syndrome in the telomeric region of the short arm of chromosome 16. A critical region where the candidate genes for the ID map has been established. In a pediatric patient with Hemoglobin H disease, dysmorphic features and ID, 4 novel and clinically relevant Copy Number Variants were identified. PCR‐GAP, MLPA and FISH analyses established the cause of the α‐thalassemia. SNP‐array analysis revealed the presence of 4 altered loci: 3 deletions (arr[hg19]Chr16(16p13.3; 88,165‐1,507,988) x1; arr[hg19]Chr6(6p21.1; 44,798,701‐45,334,537) x1 and arr[hg19]Chr17(17q25.3; 80,544,855‐81,057,996) x1) and a terminal duplication (arr[hg19]Chr7(7p22.3‐p22.2; 4,935‐4,139,785) x3). The ‐α3.7 mutation and the ∼1.51 Mb in 16p13.3 are involved in the alpha‐thalassemic phenotype. However, the critical region for ATR‐16 cannot be narrowed down. The deletion affecting 6p21.1 removes the first 2 exons and part of intron 2 of the RUNX2 gene. Although heterozygous loss of function mutations affecting this gene have been associated with cleidocranial dysplasia, the patient does not exhibit pathognomonic signs of this syndrome, possibly due to the fact that the isoform d of the transcription factor remains unaffected. This work highlights the importance of searching for cryptic deletions in patients with ID and reiterates the need of the molecular analysis when it is associated to microcytic hypochromic anemia with normal iron status. © 2016 Wiley Periodicals, Inc.
Clinical, cytogenetic, and molecular outcomes in a series of 66 patients with Pierre Robin sequence and literature review: 22q11.2 deletion is less common than other chromosomal anomalies
Authors: Gomez‐Ospina Natalia , Bernstein Jonathan A.
Published: January 2016

Pierre Robin sequence (PRS) is an important craniofacial anomaly that can be seen as an isolated finding or manifestation of multiple syndromes. 22q11.2 deletion and Stickler syndrome are cited as the two most common conditions associated with PRS, but their frequencies are debated. We performed a retrospective study of 66 patients with PRS and reviewed their genetic testing, diagnoses, and clinical findings. The case series is complemented by a comprehensive literature review of the nature and frequency of genetic diagnosis in PRS. In our cohort 65% of patients had associated anomalies; of these, a genetic diagnosis was established in 56%. Stickler syndrome was the most common diagnosis, comprising approximately 11% of all cases, followed by Treacher Collins syndrome (9%). The frequency of 22q11.2 deletion was 1.5%. Chromosome arrays, performed for 72% of idiopathic PRS with associated anomalies, revealed two cases of 18q22→qter deletion, a region not previously reported in association with PRS. A review of the cytogenetic anomalies identified in this population supports an association between the 4q33‐qter, 17q24.3, 2q33.1, and 11q23 chromosomal loci and PRS. We found a low frequency of 22q11.2 deletion in PRS, suggesting it is less commonly implicated in this malformation. Our data also indicate a higher frequency of cytogenetic anomalies in PRS patients with associated anomalies, and a potential new link with the 18q22→qter locus. The present findings underscore the utility of chromosomal microarrays in cases of PRS with associated anomalies and suggest that delaying testing for apparently isolated cases should be considered. © 2016 Wiley Periodicals, Inc.
Longitudinal predictors of cannabis use and dependence in offspring from families at ultra high risk for alcohol dependence and in control families
Authors: Hill Shirley Y. , Jones Bobby L. , Steinhauer Stuart R. , Zezza Nicholas , Stiffler Scott
Published: January 2016

Cannabis use is common among adolescents. Identification of the factors associated with continued heavy use into young adulthood and development of cannabis abuse and dependence is of considerable importance. The role of familial risk for addiction and an associated endophenotype, P300 amplitude, has not previously been related to cannabis use and dependence. A prospective longitudinal study spanning childhood and young adulthood provided the opportunity for exploring these factors, along with genetic variation, in the cannabis use behaviors of 338 young adult offspring from high and low familial risk for alcohol dependence families (ages 19–30). P300 data were collected multiple times in childhood. The association between young adult patterns of cannabis use or cannabis abuse/dependence was tested with genetic variation in the cannabinoid gene, CNR1, the ANKK1‐DRD2 gene, and childhood developmental trajectories of P300. Young adult patterns of cannabis use was characterized by three patterns: (i) no use throughout; (ii) declining use from adolescence through young adulthood; and (iii) frequent use throughout. Following the low P300 trajectory in childhood predicted cannabis abuse and dependence by young adulthood. A four SNP ANKK1‐DRD2 haplotype (G‐G‐G‐C) was found to be significantly associated with the frequency of use patterns (P = 0.0008). Although CNR1 variation overall was not significantly associated with these patterns, among individuals with cannabis abuse/dependence the presence of one or both copies of the rs806368 A > G minor allele conferred a 5.4‐fold increase (P = 0.003) in the likelihood that they would be in the frequent and persistent use group rather than the declining use group. © 2016 Wiley Periodicals, Inc.
The impact of CACNA1C allelic variation on regional gray matter volume in Chinese population
Authors: Huang Liang , Mo Yin , Sun Xuejin , Yu Hualin , Li Hao , Wu Lichuan , Li Ming
Published: January 2016

The SNP rs1006737 in CACNA1C gene has been significantly associated with psychiatric disorders (e.g., schizophrenia and bipolar disorder) in European populations. In Han Chinese, rs1006737 is also strongly associated with schizophrenia, although the effects of the psychosis risk SNP on related brain functions and structures in this population remain unclear. Here, we examined the association of rs1006737 with gray matter volume in a sample of 278 healthy Han Chinese. A whole‐brain voxel‐based morphometry (VBM) analysis revealed a significant association in the region around right superior occipital gyrus (family‐wise error corrected, P = 0.023). Our data provides initial evidence for the involvement of this psychosis genetic risk locus in brain structure variations in Chinese population, and calls for further investigations. © 2016 Wiley Periodicals, Inc.
Midazolam dose correlates with abnormal hippocampal growth and neurodevelopmental outcome in preterm infants
Authors: Duerden Emma G. , Guo Ting , Dodbiba Lorin , Chakravarty M. Mallar , Chau Vann , Poskitt Kenneth J. , Synnes Anne , Grunau Ruth E. , Miller Steven P.
Published: January 2016

Objective

Very preterm‐born neonates (24–32 weeks of gestation) are exposed to stressful and painful procedures during neonatal intensive care. Analgesic and sedation therapies are essential, and opiates and benzodiazepines are commonly used. These medications may negatively impact brain development. The hippocampus may be especially vulnerable to the effects of pain and analgesic and/or sedative therapies and contribute to adverse outcomes. The effect of invasive procedures and analgesic–sedative exposure on hippocampal growth was assessed, as was that of hippocampal growth on neurodevelopmental outcome.

Methods

A total of 138 neonates (51% male, median gestational age = 27.7 weeks) underwent magnetic resonance imaging and diffusion tensor imaging (DTI) scans, early in life (postmenstrual age [PMA] = 32.3 weeks) and at term‐equivalent age (PMA = 40.2 weeks). Volumes and DTI measures of axial diffusivity, radial diffusivity, and mean diffusivity (MD) were obtained from the hippocampus. Cognitive, language, and motor abilities were assessed using the Bayley Scales of Infant Development–III at 18.7 months median corrected age. Models testing the association of invasive procedures with hippocampal volumes and DTI measures accounted for birth gestational age, sex, PMA, dose of analgesics/sedatives (fentanyl, morphine, midazolam), mechanical ventilation, hypotension, and surgeries.

Results

Total midazolam dose predicted decreased hippocampal volumes (β = −1.8, p < 0.001) and increased MD (β = 0.002, p = 0.02), whereas invasive procedures did not (β = 0, p > 0.5 each). Lower cognitive scores were associated with hippocampal growth (β = −0.31, p = 0.003), midazolam dose (β = −0.27, p = 0.03), and surgery (β = −8.32, p = 0.04).

Interpretation

Midazolam exposure was associated with macro‐ and microstructural alterations in hippocampal development and poorer outcomes consistent with hippocampal dysmaturation. Use of midazolam in preterm neonates, particularly those not undergoing surgery, is cautioned. Ann Neurol 2016;79:548–559
Visualisierung proteinspezifischer Glycosylierung in lebenden Zellen
Authors: Doll Franziska , Buntz Annette , Späte Anne‐Katrin , Schart Verena F. , Timper Alexander , Schrimpf Waldemar , Hauck Christof R. , Zumbusch Andreas , Wittmann Valentin
Published: January 2016

Die Glycosylierung von Proteinen ist eine weit verbreitete posttranslationale Modifikation, die an der Regulation vieler Proteinfunktionen beteiligt ist. Um die biologischen Funktionen dieser Modifikation zu verstehen, wäre die Visualisierung des Glycosylierungszustandes spezifischer Proteine in lebenden Zellen von entscheidender Bedeutung. Bisher wurde dies noch nicht erreicht. Hier zeigen wir die Detektion proteinspezifischer Glycosylierung der intrazellulären Proteine OGT, Foxo1, p53 und Akt1 in lebenden Zellen. Unser breit anwendbarer Ansatz beruht auf der Fluoreszenzmarkierung intrazellulärer, metabolisch eingebauter Kohlenhydrate durch Diels‐Alder‐Chemie. Die gewählten Proteine sind mit grün fluoreszierendem Protein (EGFP) markiert. Fluoreszenzlebenszeitmikroskopie (FLIM) gestattet die Detektion von Förster‐Resonanzenergietransfer (FRET) zwischen EGFP und dem am Glycan gebundenen Fluorophor mit hohem Kontrast selbst in Gegenwart des großen Überschusses an Akzeptorfluorophor.
Optimal Synthetic Glycosylation of a Therapeutic Antibody
Authors: Parsons Thomas B. , Struwe Weston B. , Gault Joseph , Yamamoto Keisuke , Taylor Thomas A. , Raj Ritu , Wals Kim , Mohammed Shabaz , Robinson Carol V. , Benesch Justin L. P. , Davis Benjamin G.
Published: January 2016

Glycosylation patterns in antibodies critically determine biological and physical properties but their precise control is a significant challenge in biology and biotechnology. We describe herein the optimization of an endoglycosidase‐catalyzed glycosylation of the best‐selling biotherapeutic Herceptin, an anti‐HER2 antibody. Precise MS analysis of the intact four‐chain Ab heteromultimer reveals nonspecific, non‐enzymatic reactions (glycation), which are not detected under standard denaturing conditions. This competing reaction, which has hitherto been underestimated as a source of side products, can now be minimized. Optimization allowed access to the purest natural form of Herceptin to date (≥90 %). Moreover, through the use of a small library of sugars containing non‐natural functional groups, Ab variants containing defined numbers of selectively addressable chemical tags (reaction handles at Sia C1) in specific positions (for attachment of cargo molecules or “glycorandomization”) were readily generated.
A Mononuclear CoII Coordination Complex Locked in a Confined Space and Acting as an Electrochemical Water‐Oxidation Catalyst: A “Ship‐in‐a‐Bottle” Approach
Authors: Manna Paulami , Debgupta Joyashish , Bose Suranjana , Das Samar K.
Published: January 2016

Preparing efficient and robust water oxidation catalyst (WOC) with inexpensive materials remains a crucial challenge in artificial photosynthesis and for renewable energy. Existing heterogeneous WOCs are mostly metal oxides/hydroxides immobilized on solid supports. Herein we report a newly synthesized and structurally characterized metal–organic hybrid compound [{Co3(μ3‐OH)(BTB)2(dpe)2} {Co(H2O)4(DMF)2}0.5]n⋅n H2O (Co‐WOC‐1) as an effective and stable water‐oxidation electrocatalyst in an alkaline medium. In the crystal structure of Co‐WOC‐1, a mononuclear CoII complex {Co(H2O)4(DMF)2}2+ is encapsulated in the void space of a 3D framework structure and this translationally rigid complex cation is responsible for a remarkable electrocatalytic WO activity, with a catalytic turnover frequency (TOF) of 0.05 s−1 at an overpotential of 390 mV (vs. NHE) in 0.1 m KOH along with prolonged stability. This host–guest system can be described as a “ship‐in‐a‐bottle”, and is a new class of heterogeneous WOC.
Use of a “Catalytic” Cosolvent, N,N‐Dimethyl Octanamide, Allows the Flow Synthesis of Imatinib with no Solvent Switch
Authors: Yang Jeffrey C. , Niu Dawen , Karsten Bram P. , Lima Fabio , Buchwald Stephen L.
Published: January 2016

A general, efficient method for C−N cross‐coupling has been developed using N,N‐dimethyloctanamide as a catalytic cosolvent for biphasic continuous‐flow applications. The described method was used to generate a variety of biarylamines and was integrated into a two‐step sequence which converted phenols into biarylamines via either triflates or tosylates. Additionally, the method was applied to a three‐step synthesis of imatinib, the API of Gleevec, in good yield without the need of solvent switches.
Stereoselective Synthesis of Polycycles Containing an Aziridine Group: Intramolecular aza‐Diels–Alder Reactions of Unactivated 2H‐Azirines with Unactivated Dienes
Authors: Xu Hua‐Dong , Zhou Hao , Pan Ying‐Peng , Ren Xin‐Tao , Wu Hao , Han Mei , Han Run‐Ze , Shen Mei‐Hua
Published: January 2016

Vinyl azide with a pendent diene can undergo thermal decomposition to a related azirine intermediate, which was used immediately in an intramolecular aza‐Diels–Alder reaction to furnish an aziridine‐containing trans‐fused tricyclic core structure with excellent stereoselectivity. The method provides a facile entry to complex polycyclic alkaliods which can be further elaborated by ring‐opening reactions and ring expansion of the aziridine moiety, as well as by dihydroxylation of the alkene group.
Total Synthesis of (±)‐Alstoscholarisine A
Authors: Bihelovic Filip , Ferjancic Zorana
Published: January 2016

The first total synthesis of the neuroactive indole alkaloid (±)‐alstoscholarisine A is reported. The key step of the concise synthesis is an efficient domino sequence that was used to assemble the 2,8‐diazabicyclo[3.3.1]nonane core through the formation of two C−N bonds and one C−C bond in a single step.
Strong‐Coupled Cobalt Borate Nanosheets/Graphene Hybrid as Electrocatalyst for Water Oxidation Under Both Alkaline and Neutral Conditions
Authors: Chen Pengzuo , Xu Kun , Zhou Tianpei , Tong Yun , Wu Junchi , Cheng Han , Lu Xiuli , Ding Hui , Wu Changzheng , Xie Yi
Published: January 2016

Developing highly active catalysts for the oxygen evolution reaction (OER) is of paramount importance for designing various renewable energy storage and conversion devices. Herein, we report the synthesis of a category of Co‐Pi analogue, namely cobalt‐based borate (Co‐Bi) ultrathin nanosheets/graphene hybrid by a room‐temperature synthesis approach. Benefiting from the high surface active sites exposure yield, enhanced electron transfer capacity, and strong synergetic coupled effect, this Co‐Bi NS/G hybrid shows high catalytic activity with current density of 10 mA cm−2 at overpotential of 290 mV and Tafel slope of 53 mV dec−1 in alkaline medium. Moreover, Co‐Bi NS/G electrocatalysts also exhibit promising performance under neutral conditions, with a low onset potential of 235 mV and high current density of 14.4 mA cm−2 at 1.8 V, which is the best OER performance among well‐developed Co‐based OER electrocatalysts to date. Our finding paves a way to develop highly active OER electrocatalysts.
Visualization of Protein‐Specific Glycosylation inside Living Cells
Authors: Doll Franziska , Buntz Annette , Späte Anne‐Katrin , Schart Verena F. , Timper Alexander , Schrimpf Waldemar , Hauck Christof R. , Zumbusch Andreas , Wittmann Valentin
Published: January 2016

Protein glycosylation is a ubiquitous post‐translational modification that is involved in the regulation of many aspects of protein function. In order to uncover the biological roles of this modification, imaging the glycosylation state of specific proteins within living cells would be of fundamental importance. To date, however, this has not been achieved. Herein, we demonstrate protein‐specific detection of the glycosylation of the intracellular proteins OGT, Foxo1, p53, and Akt1 in living cells. Our generally applicable approach relies on Diels–Alder chemistry to fluorescently label intracellular carbohydrates through metabolic engineering. The target proteins are tagged with enhanced green fluorescent protein (EGFP). Förster resonance energy transfer (FRET) between the EGFP and the glycan‐anchored fluorophore is detected with high contrast even in presence of a large excess of acceptor fluorophores by fluorescence lifetime imaging microscopy (FLIM).
Small‐Molecule PROTACS: New Approaches to Protein Degradation
Authors: Toure Momar , Crews Craig M.
Published: January 2016

The current inhibitor‐based approach to therapeutics has inherent limitations owing to its occupancy‐based model: 1) there is a need to maintain high systemic exposure to ensure sufficient in vivo inhibition, 2) high in vivo concentrations bring potential for off‐target side effects, and 3) there is a need to bind to an active site, thus limiting the drug target space. As an alternative, induced protein degradation lacks these limitations. Based on an event‐driven model, this approach offers a novel catalytic mechanism to irreversibly inhibit protein function by targeting protein destruction through recruitment to the cellular quality control machinery. Prior protein degrading strategies have lacked therapeutic potential. However, recent reports of small‐molecule‐based proteolysis‐targeting chimeras (PROTACs) have demonstrated that this technology can effectively decrease the cellular levels of several protein classes.
Reactive Oxygen Species Play an Important Role in the Bactericidal Activity of Quinolone Antibiotics
Authors: Kottur Jithesh , Nair Deepak T.
Published: January 2016

Recent studies posit that reactive oxygen species (ROS) contribute to the cell lethality of bactericidal antibiotics. However, this conjecture has been challenged and remains controversial. To resolve this controversy, we adopted a strategy that involves DNA polymerase IV (PolIV). The nucleotide pool of the cell gets oxidized by ROS and PolIV incorporates the damaged nucleotides (especially 8oxodGTP) into the genome, which results in death of the bacteria. By using a combination of structural and biochemical tools coupled with growth assays, it was shown that selective perturbation of the 8oxodGTP incorporation activity of PolIV results in considerable enhancement of the survival of bacteria in the presence of the norfloxacin antibiotic. Our studies therefore indicate that ROS induced in bacteria by the presence of antibiotics in the environment contribute significantly to cell lethality.
Direct Observation of Self‐Organized Water‐Containing Structures in the Liquid Phase and Their Influence on 5‐(Hydroxymethyl)furfural Formation in Ionic Liquids
Authors: Kashin Alexey S. , Galkin Konstantin I. , Khokhlova Elena A. , Ananikov Valentine P.
Published: January 2016

Water‐containing organic solutions are widespread reaction media in organic synthesis and catalysis. This type of multicomponent liquid system has a number of unique properties because of the tendency for water to self‐organize in mixtures with other liquids. The characterization of these water domains is a challenging task because of their soft and dynamic nature. In the present study, the morphology and dynamics of micrometer‐ and nanometer‐scale water‐containing compartments in ionic liquids were directly observed by electron microscopy. A variety of morphologies, including isolated droplets, dense structures, aggregates, and 2D meshworks, have been experimentally detected and studied. Using the developed method, the impact of water on the acid‐catalyzed biomass conversion reaction was studied at the microscopic level. The process that produced nanostructured domains in solution led to better yields and higher selectivities compared with reactions involving the bulk system.
Single‐Cell Mass Spectrometry for Discovery Proteomics: Quantifying Translational Cell Heterogeneity in the 16‐Cell Frog (Xenopus) Embryo
Authors: Lombard‐Banek Camille , Moody Sally A. , Nemes Peter
Published: January 2016

We advance mass spectrometry from a cell population‐averaging tool to one capable of quantifying the expression of diverse proteins in single embryonic cells. Our instrument combines capillary electrophoresis (CE), electrospray ionization, and a tribrid ultrahigh‐resolution mass spectrometer (HRMS) to enable untargeted (discovery) proteomics with ca. 25 amol lower limit of detection. CE‐μESI‐HRMS enabled the identification of 500–800 nonredundant protein groups by measuring 20 ng, or <0.2% of the total protein content in single blastomeres that were isolated from the 16‐cell frog (Xenopus laevis) embryo, amounting to a total of 1709 protein groups identified between n=3 biological replicates. By quantifying ≈150 nonredundant protein groups between all blastomeres and replicate measurements, we found significant translational cell heterogeneity along multiple axes of the embryo at this very early stage of development when the transcriptional program of the embryo has yet to begin.
Catalyst‐Controlled Switch in Chemo‐ and Diastereoselectivities: Annulations of Morita–Baylis–Hillman Carbonates from Isatins
Authors: Zhan Gu , Shi Ming‐Lin , He Qing , Lin Wei‐Jia , Ouyang Qin , Du Wei , Chen Ying‐Chun
Published: January 2016

Regulating both the chemo‐ and diastereoselectivity, divergently, of a reaction is highly attractive but extremely challenging. Presented herein is a catalyst‐controlled switch in the chemo‐ and diastereodivergent annulation reactions of Morita–Baylis–Hillman carbonates, derived from isatins and 2‐alkylidene‐1H‐indene‐1,3(2H)‐diones, in exclusive α‐regioselectivity. α‐Isocupreine efficiently catalyzed [2+1] reactions to access cyclopropane derivatives, and the diastereodivergent [3+2] annulations were accomplished by employing either a chiral phosphine or a DMAP‐type molecule. All reactions exhibited excellent chemoselectivities, and good to remarkable stereoselectivities were furnished, thus leading to a collection of compounds with skeletal and stereogenic diversity. Moreover, DFT computational calculations elucidated the catalyst‐based switch in mechanism.
Electroresponsive Structurally Colored Materials: A Combination of Structural and Electrochromic Effects
Authors: Kuno Tomoya , Matsumura Yoshimasa , Nakabayashi Koji , Atobe Mahito
Published: January 2016

Electroresponsive structurally colored materials composed of ordered arrays of polyaniline@poly(methyl methacrylate) (PANI@PMMA) core–shell nanoparticles have been successfully prepared. The core–shell nanoparticles were synthesized by deposition of PANI shells on the surfaces of the PMMA cores by the oxidative polymerization of anilinium chloride. Ordered arrays were then fabricated by using the fluidic cell method. Because the ordered arrays and the PANI shells generate structural and electrochromic colors, respectively, these core–shell colloidal crystals exhibited colors resulting from the combined effects of these materials. The crystal colors depended greatly on the size of PANI@PMMA particles and could also be varied by the application of a voltage. The electrochromic colors of these arrays were found to be quite different from those exhibited by pure PANI films prepared by electrochemical oxidation.
Synthesis of a perfluorooctanoic acid molecularly imprinted polymer for the selective removal of perfluorooctanoic acid in an aqueous environment
Authors: Cao Fengmei , Wang Lei , Ren Xinhao , Sun Hongwen
Published: January 2016

Perfluorooctanoic acid (PFOA) contamination in the environment is a global problem. The aqueous phase is the main medium for PFOA because of its moderate solubility. Adsorption is a feasible way to remove PFOA because of its chemical and biological stability. In this study, a new type of molecularly imprinted polymer (MIP) for the selective adsorption of PFOA in aqueous solutions was synthesized by the precipitation polymerization method with PFOA as the template molecule after optimization. The adsorption kinetics and isotherms of the MIP adsorbent toward PFOA were studied, and the effects of the pH and cations on the adsorption were investigated with batch experiments. The results show that acrylamide (AAM) was the best functional monomer, and the optimal molar ratio of PFOA to AAM to ethylene glycol dimethacrylate (crosslinker) was 1:6:25. The optimized MIP adsorbent had a high affinity for PFOA, and the uptake percentage by the MIP adsorbent was 1.3–2.5 times that of the nonimprinted polymer (NIP) when PFOA existed alone. A maximum PFOA sorption capacity of 5.45 mg/g based on the Langmuir isotherm model was achieved with the MIP adsorbent. The MIP adsorbent exhibited a high selectivity for PFOA over competitive compounds (other perfluorinated alkyl carboxylic and sulfonic acids), whereas the NIP did not. Approximately 90% of the PFOA in the mixture was removed by the MIP adsorbent; this was 18 times that of the NIP. Moreover, the regenerability of the MIP adsorbent was confirmed in five sequential adsorption–desorption cycles without a significant reduction in the PFOA uptake. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43192.
Tissue Levels of Stefin A and Stefin B in Hepatocellular Carcinoma
Authors: Lin Yang‐Yuan , Chen Zhi‐Wei , Lin Zhi‐Ping , Lin Li‐Bin , Yang Xue‐Ming , Xu Li‐Yan , Xie Qun
Published: January 2016

Stefins have been reported to be associated with the progression and metastasis of various malignant tumors. However, the expressions of stefins in hepatocellular carcinoma (HCC) have not been well‐defined. In this study, the protein levels of stefin A and stefin B were assessed by immunohistochemical staining, and the mRNA levels were quantified by real‐time polymerase chain reaction in 85 primary HCC tissues, 85 surrounding non‐cancerous tissues, and 9 normal hepatic tissues. The immunohistochemical staining of cathepsin B and cathepsin D, and the ratio of cathepsins to stefins were assessed. The mRNA expressions of stefin A and stefin B in HCC tissues were significantly higher than surrounding noncancerous tissues and normal hepatic tissues, respectively. A significant positive relationship of stefin A and stefin B was found with node metastasis, tumor size, and Edmondson grade for HCC. Univariate and multivariate analyses revealed that Edmondson grade and stefin B expression were independent factors associated with the risk of lymph node metastasis in HCC. The ratios of cathepsin B to stefin A, cathepsin D to stefin A, cathepsin B to stefin B and cathepsin D to stefin B of the HCC group were significantly higher than that of the surrounding noncancerous group. A significant positive correlation between the ratio of cathepsins to stefins (cathepsin B/stefin A, cathepsin B/stefin B and cathepsin D/stefin B) and node metastasis was demonstrated. We concluded that high expressions of stefin A and stefin B may be an important factor contributing to the development and metastasis of HCC. Anat Rec, 299:428–438, 2016. © 2016 Wiley Periodicals, Inc.
Free‐Standing Membranes to Study the Optical Properties of Anodic TiO2 Nanotube Layers
Authors: Cha Gihoon , Schmuki Patrik , Altomare Marco
Published: January 2016

In the present work we investigate various optical properties (such as light absorption and reflectance) of anodic TiO2 nanotube layers directly transferred as self‐standing membranes onto quartz substrates. This allows investigation in a transmission geometry which provides significantly more reliable data than measurements on the metallic Ti substrate. Light transmission and reflectance measurements were carried out for layers of thickness varying from 1.8 to 50 μm, and the layers were investigated in their amorphous and crystalline forms. A series of wavelength‐dependent light attenuation coefficients are extrapolated and found to match the photocurrent versus irradiation wavelength behavior. A feature specific to anodic nanotubes is that their intrinsic carbon contamination content causes a proportional sub‐bandgap response. Overall, the extracted data provide a valuable basis and understanding for the design of photo‐electrochemical devices based on TiO2 nanotubes.
Optimization and modeling for the synthesis of sterol esters from deodorizer distillate by lipase‐catalyzed esterification
Authors: Zhang Xinyu , Yu Jiang , Zeng Aiwu
Published: January 2016

In this paper, cotton seed oil deodorizer distillate (CSODD), was recovered to obtain fatty acid sterol ester (FASE), which is one of the biological activated substances added as human therapeutic to lower cholesterol. Esterification reactions were carried out using Candida rugosa lipase as a catalyst, and the conversion of phytosterol was optimized using response surface methodology. The highest conversion (90.8 ± 0.4%) was reached at 0.84 wt% enzyme load, 1:25 solvent/CSODD mass ratio, and 44.2 °C after 12 H reaction. A kinetic model based on the reaction rate equation was developed to describe the reaction process. The activation energy of the reaction was calculated to be 56.9 kJ/mol and the derived kinetic parameters provided indispensable basics for further study. The optimization and kinetic research of synthesizing FASE from deodorizer distillate provided necessary information for the industrial applications in the near future. Experimental results showed that the proposed process is a promising alternative to recycle sterol esters from vegetable oil deodorizer distillates in a mild, efficient, and environmental friendly method.
Optimization of a cytochrome P450 oxidation system for enhancing protopanaxadiol production in Saccharomyces cerevisiae
Authors: Zhao Fanglong , Bai Peng , Liu Ting , Li Dashuai , Zhang Xiangmei , Lu Wenyu , Yuan Yingjin
Published: January 2016

Ginsenosides, the major bioactive components of Panax ginseng, are regarded as promising high‐value pharmaceutical compounds. In ginseng, ginsenosides are produced from their precursor protopanaxadiol. Recently, an artificial biosynthetic pathway of protopanaxadiol was built in Saccharomyces cerevisiae by introducing a P. ginseng dammarenediol‐II synthase, a P. ginseng cytochrome P450‐type protopanaxadiol synthase (PPDS), and a Arabidopsis thaliana NADPH‐cytochrome P450 reductase (ATR1). In this engineered yeast strain, however, the low metabolic flux through PPDS resulted in a low productivity of protopanaxadiol. Moreover, health of the yeast cells was significantly affected by reactive oxygen species released by the pool coupling between PPDS and ATR1. To overcome the obstacles in protopanaxadiol production, PPDS was modified through transmembrane domain truncation and self‐sufficient PPDS–ATR1 fusion construction in this study. The fusion enzymes conferred approximately 4.5‐fold increase in catalytic activity, and 71.1% increase in protopanaxadiol production compared with PPDS and ATR1 co‐expression. Our in vivo experiment indicated that the engineered yeast carrying fusion protein effectively converted 96.8% of dammarenediol‐II into protopanaxadiol. Protopanaxadiol production in a 5 L bioreactor in fed‐batch fermentation reached 1436.6 mg/L. Our study not only improved protopanaxadiol production in yeast, but also provided a generic method to improve activities of plant cytochrome P450 monooxygenases. This method is promising to be applied to other P450 systems in yeast. Biotechnol. Bioeng. 2016;113: 1787–1795. © 2016 Wiley Periodicals, Inc.
Quantifying brain volumes for Multiple Sclerosis patients follow‐up in clinical practice – comparison of 1.5 and 3 Tesla magnetic resonance imaging
Authors: Lysandropoulos Andreas P. , Absil Julie , Metens Thierry , Mavroudakis Nicolas , Guisset François , Van Vlierberghe Eline , Smeets Dirk , David Philippe , Maertens Anke , Van Hecke Wim
Published: January 2016

Introduction

There is emerging evidence that brain atrophy is a part of the pathophysiology of Multiple Sclerosis (MS) and correlates with several clinical outcomes of the disease, both physical and cognitive. Consequently, brain atrophy is becoming an important parameter in patients' follow‐up. Since in clinical practice both 1.5Tesla (T) and 3T magnetic resonance imaging (MRI) systems are used for MS patients follow‐up, questions arise regarding compatibility and a possible need for standardization.

Methods

Therefore, in this study 18 MS patients were scanned on the same day on a 1.5T and a 3T scanner. For each scanner, a 3D T1 and a 3D FLAIR were acquired. As no atrophy is expected within 1 day, these datasets can be used to evaluate the median percentage error of the brain volume measurement for gray matter (GM) volume and parenchymal volume (PV) between 1.5T and 3T scanners. The results are obtained with MSmetrix, which is developed especially for use in the MS clinical care path, and compared to Siena (FSL), a widely used software for research purposes.

Results

The MSmetrix median percentage error of the brain volume measurement between a 1.5T and a 3T scanner is 0.52% for GM and 0.35% for PV. For Siena this error equals 2.99%. When data of the same scanner are compared, the error is in the order of 0.06–0.08% for both MSmetrix and Siena.

Conclusions

MSmetrix appears robust on both the 1.5T and 3T systems and the measurement error becomes an order of magnitude higher between scanners with different field strength.
Restabilization of Acrylic Acid in Isoperibolic Reactors
Authors: Pfeifer Christian A. , Vizer Artur , Vogel Herbert
Published: January 2016

The spontaneous polymerization, i.e, runaway, of acrylic acid during storage is a serious problem which may endanger life and facilities. In respond to a starting polymerization, effective emergency measures are necessary. For these investigations, a polytropic reactor setup, namely, an isoperibolic reactor is introduced to offer a rational access to restabilization studies. Furthermore, safety diagrams are created where the used amount of stabilizer is plotted against the polymerization progress in terms of the rising temperature. Such diagrams display the minimum required amount of the shortstopper (RESTAB™) for terminating a runaway polymerization. The suitability of the reaction setup is investigated using unstabilized acrylic acid.
Bismuth Nanoparticles Embedded in Carbon Spheres as Anode Materials for Sodium/Lithium‐Ion Batteries
Authors: Yang Fuhua , Yu Fan , Zhang Zhian , Zhang Kai , Lai Yanqing , Li Jie
Published: January 2016

Sodium‐ion batteries (SIBs) are regarded as an attractive alternative to lithium‐ion batteries (LIBs) for large‐scale commercial applications, because of the abundant terrestrial reserves of sodium. Exporting suitable anode materials is the key to the development of SIBs and LIBs. In this contribution, we report on the fabrication of Bi@C microspheres using aerosol spray pyrolysis technique. When used as SIBs anode materials, the Bi@C microsphere delivered a high capacity of 123.5 mAh g−1 after 100 cycles at 100 mA g−1. The rate performance is also impressive (specific capacities of 299, 252, 192, 141, and 90 mAh g−1 are obtained under current densities of 0.1, 0.2, 0.5, 1, and 2 A g−1, respectively). Furthermore, the Bi@C microsphere also proved to be suitable LIB anode materials. The excellent electrochemical performance for both SIBs and LIBs can attributed to the Bi@C microsphere structure with Bi nanoparticles uniformly dispersed in carbon spheres.
Peroxide Coordination of Tellurium in Aqueous Solutions
Authors: Mikhaylov Alexey A. , Medvedev Alexander G. , Churakov Andrei V. , Grishanov Dmitry A. , Prikhodchenko Petr V. , Lev Ovadia
Published: January 2016

Tellurium–peroxo complexes in aqueous solutions have never been reported. In this work, ammonium peroxotellurates (NH4)4Te2(μ‐OO)2(μ‐O)O4(OH)2 (1) and (NH4)5Te2(μ‐OO)2(μ‐O)O5(OH)⋅1.28 H2O⋅0.72 H2O2 (2) were isolated from 5 % hydrogen peroxide aqueous solutions of ammonium tellurate and characterized by single‐crystal and powder X‐ray diffraction analysis, by Raman spectroscopy and thermal analysis. The crystal structure of 1 comprises ammonium cations and a symmetric binuclear peroxotellurate anion [Te2(μ‐OO)2(μ‐O)O4(OH)2]4−. The structure of 2 consists of an unsymmetrical [Te2(μ‐OO)2(μ‐O)O5(OH)]5− anion, ammonium cations, hydrogen peroxide, and water. Peroxotellurate anions in both 1 and 2 contain a binuclear Te2(μ‐OO)2(μ‐O) fragment with one μ‐oxo‐ and two μ‐peroxo bridging groups. 125Te NMR spectroscopic analysis shows that the peroxo bridged bitellurate anions are the dominant species in solution, with 3–40 %wt H2O2 and for pH values above 9. DFT calculations of the peroxotellurate anion confirm its higher thermodynamic stability compared with those of the oxotellurate analogues. This is the first direct evidence for tellurium–peroxide coordination in any aqueous system and the first report of inorganic tellurium–peroxo complexes. General features common to all reported p‐block element peroxides could be discerned by the characterization of aqueous and crystalline peroxotellurates.
The Chemical Bond in C2
Authors: Hermann Markus , Frenking Gernot
Published: January 2016

Quantum chemical calculations using the complete active space of the valence orbitals have been carried out for HnCCHn (n=0–3) and N2. The quadratic force constants and the stretching potentials of HnCCHn have been calculated at the CASSCF/cc‐pVTZ level. The bond dissociation energies of the C−C bonds of C2 and HC≡CH were computed using explicitly correlated CASPT2‐F12/cc‐pVTZ‐F12 wave functions. The bond dissociation energies and the force constants suggest that C2 has a weaker C−C bond than acetylene. The analysis of the CASSCF wavefunctions in conjunction with the effective bond orders of the multiple bonds shows that there are four bonding components in C2, while there are only three in acetylene and in N2. The bonding components in C2 consist of two weakly bonding σ bonds and two electron‐sharing π bonds. The bonding situation in C2 can be described with the σ bonds in Be2 that are enforced by two π bonds. There is no single Lewis structure that adequately depicts the bonding situation in C2. The assignment of quadruple bonding in C2 is misleading, because the bond is weaker than the triple bond in HC≡CH.
Hydrazine‐Assisted Liquid Exfoliation of MoS2 for Catalytic Hydrodeoxygenation of 4‐Methylphenol
Authors: Liu Guoliang , Ma Hualong , Teixeira Ivo , Sun Zhenyu , Xia Qineng , Hong Xinlin , Tsang Shik Chi Edman
Published: January 2016

A simple but effective method to exfoliate bulk MoS2 in a range of solvents is presented for the preparation of colloid flakes consisted of one to a few molecular layers by application of ultrasonic treatment in N2H4. Their high yield in solution and exposure of more active surface sites allows the synthesis of corresponding solid catalysts with remarkably high activity in hydrodeoxygenation of 4‐methylphenol and this method can also be applied to other two dimensional materials.