bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of gold nanoparticles on extracellular nutrient-cycling enzyme activity and bacterial community in soil slurries: role of nanoparticle size and surface coating
Authors: Asadishad Bahareh , Chahal Shawninder , Cianciarelli Vanessa , Zhou Kevin , Tufenkji Nathalie
Published: February 2017

Engineered nanoparticles such as gold that are considered to be relatively chemically inert can influence soil enzyme activities and the composition of microbial communities that play an important role in nutrient cycling and soil health.
Catalytic hydrodeoxygenation of anisole: an insight into the role of metals in transalkylation reactions in bio-oil upgrading
Authors: Wang Hongliang , Feng Maoqi , Yang Bin
Published: February 2017

High temperature and metal catalysts with moderate hydrogenolysis and hydrogenation activity facilitated transalkylation during HDO upgrading of lignin-derived bio-oil compounds.
A new method for high-precision palladium isotope analyses of iron meteorites and other metal samples
Authors: Ek Mattias , Hunt Alison C. , Schönbächler Maria
Published: February 2017

We present a new method for separation of Pd from an iron meteorite matrix and high precision analyses of all isotopes via multi collector ICP-MS.
Biologically inspired self-assembly of bacitracin-based platinum nanoparticles with anti-tumor effects
Authors: Yin Tian , Wang Zi , Li Xiaoling , Li Yanji , Bian Kexin , Cao Weiwei , He Yuchu , Liu Huan , Niu Kang , Gao Dawei
Published: February 2017

The green synthesis of bacitracin-based platinum nanoparticles with excellent antitumor efficacyin vitroandin vivo.
Physagulide Q suppresses proliferation and induces apoptosis in human hepatocellular carcinoma cells by regulating the ROS-JAK2/Src-STAT3 signaling pathway
Authors: Yang Yan-Wei , Yang Lei , Zhang Chao , Gao Cai-Yun , Ma Ting , Kong Ling-Yi
Published: February 2017

Physagulide Q (PQ), a new natural compound, was isolated from Physalis angulata L. in our laboratory.
The marriage of AIE and interface engineering: convenient synthesis and enhanced photovoltaic performance
Authors: Wang Can , Liu Zhiyang , Li Mengshu , Xie Yujun , Li Bingshi , Wang Shuo , Xue Shan , Peng Qian , Chen Bin , Zhao Zujin , Li Qianqian , Ge Ziyi , Li Zhen
Published: February 2017

The first example of an AIE interfacial material is developed, with a high PCE of 8.94% being achieved for the TPE-2 modified conventional PC71BM:PTB7-based PSC.
Structure and luminescence properties of a Nd3+doped Bi4Ge3O12scintillation crystal: new insights from a comprehensive study
Authors: Chen Feiyang , Ju Meng , Gutsev Gennady L. , Kuang Xiaoyu , Lu Cheng , Yeung Yauyuen
Published: February 2017

We have, for the first time, identified a unique semiconducting phase of theR3 space group where impurity Nd3+ions occupy exactly the host Bi3+ion sites with trigonal symmetry.
Dynamic behaviours of a rationally prepared flexible MOF by postsynthetic modification of ligand struts
Authors: Xu Xiaoyan , Yang Fei , Chen Shi-Lu , He Jieya , Xu Yanqing , Wei Wei
Published: February 2017

A rationally prepared flexible MOF exhibits interesting dynamic behaviours such as reversible structural deformation, vapour sorption hysteresis and unexpected adsorption of bulky guest molecules.
Catalytic asymmetric Meerwein–Ponndorf–Verley reduction of glyoxylates induced by a chiral N,N′-dioxide/Y(OTf)3complex
Authors: Wu Wangbin , Zou Sijia , Lin Lili , Ji Jie , Zhang Yuheng , Ma Baiwei , Liu Xiaohua , Feng Xiaoming
Published: February 2017

An asymmetric MPV reduction of glyoxylates was for the first time achieved with excellent results and the mechanism of the reaction was probed.
Reversible DNA micro-patterning using the fluorous effect
Authors: Flynn Gabriella E. , Withers Jamie M. , Macias Gerard , Sperling Justin R. , Henry Sarah L. , Cooper Jonathan M. , Burley Glenn A. , Clark Alasdair W.
Published: February 2017

We described the use of the fluorous effect as a simple and reversible immobilisation technique for DNA.
A new and potentially prebiotic α-cytidine derivative
Authors: Tsanakopoulou Maria , Xu Jianfeng , Bond Andrew D. , Sutherland John D.
Published: February 2017

A new α-cytidine derivative was synthesised from the prebiotic reaction of ribose aminooxazoline and dicyanoacetylene.
Non-ionic surfactants from renewables – amphiphilic ligands in biphasic reactions
Authors: Faßbach Thiemo A. , Sommer Fridolin O. , Behr Arno , Romanski Steffen , Leinweber Dirk , Vorholt Andreas J.
Published: February 2017

Using the water-soluble N-methylglucamine and the non-polar β-myrcene in a biphasic telomerisation with the amphiphilic TPPMS ligand, new surfactants are obtained.
Aqueous extracts from asparagus stems prevent memory impairments in scopolamine-treated mice
Authors: Sui Zifang , Qi Ce , Huang Yunxiang , Ma Shufeng , Wang Xinguo , Le Guowei , Sun Jin
Published: February 2017

Aqueous extracts fromAsparagus officinalisL. reversed scopolamine-induced cognitive impairments by increasing acetylcholine and expression of BDNF and CREB.
Halogenated conjugated molecules for ambipolar field-effect transistors and non-fullerene organic solar cells
Authors: Yang Fan , Li Cheng , Lai Wenbin , Zhang Andong , Huang Hui , Li Weiwei
Published: February 2017

Halogenated conjugated molecules containing F, Cl, Br and I with high crystallinity were developed to show high electron mobilities of 1.3 cm2 V−1 s−1 in field-effect transistors and power conversion efficiencies above 9% in non-fullerene solar cells.
Experimental evidence of electronic polarization in a family of photo-ferroelectrics
Authors: Borkar Hitesh , Rao Vaibhav , Tomar M. , Gupta Vinay , Scott J. F. , Kumar Ashok
Published: February 2017

Anomalous change in ferroelectric polarization under illumination of monochromatic light.
A convergent synthesis of 1,3,4-oxadiazoles from acyl hydrazides under semiaqueous conditions
Authors: Tokumaru Kazuyuki , Johnston Jeffrey N.
Published: February 2017

An innovative new synthesis approach to disubstituted 1,3,4-oxadiazoles is described, inspired by Umpolung Amide Synthesis (UmAS).
Nanofiber networks of Na3V2(PO4)3 as a cathode material for high performance all-solid-state sodium-ion batteries
Authors: Gao Rongtan , Tan Rui , Han Lei , Zhao Yan , Wang Zijian , Yang Luyi , Pan Feng
Published: February 2017

NVP with nanofiber network structure was used as cathode material for all-solid-state sodium ion batteries, exhibiting outstanding electrochemical performances.
Critical study of the distribution of rotational velocities of Be stars
Authors: Zorec J. , Frémat Y. , Domiciano de Souza A. , Royer F. , Cidale L. , Hubert A.-M. , Semaan T. , Martayan C. , Cochetti Y. R. , Arias M. L. , Aidelman Y. , Stee P.
Published: February 2017

Aims.We assume that stars may undergo surface differential rotation to study its impact on the interpretation ofVsiniand on the observed distributionΦ(u) of ratios of true rotational velocitiesu=V/Vc(Vcis the equatorial critical velocity). We discuss some phenomena affecting the formation of spectral lines and their broadening, which can obliterate the information carried byVsiniconcerning the actual stellar rotation.

Methods.We studied the line broadening produced by several differential rotational laws, but adopted Maunder’s expression Ω(θ) = Ω0(1 +αcos2θ) as an attempt to account for all of these laws with the lowest possible number of free parameters. We studied the effect of the differential rotation parameterαon the measuredVsiniparameter and on the distributionΦ(u) of ratiosu=V/Vc.

Results.We conclude that the inferredVsiniis smaller than implied by the actual equatorial linear rotation velocityVeqif the stars rotate withα< 0, but is larger if the stars haveα> 0. For a given |α| the deviations ofVsiniare larger whenα< 0. If the studied Be stars have on averageα< 0, the number of rotators withVeq≃ 0.9Vcis larger than expected from the observed distributionΦ(u); if these stars have on averageα> 0, this number is lower than expected. We discuss seven phenomena that contribute either to narrow or broaden spectral lines, which blur the information on the rotation carried byVsiniand, in particular, to decide whether the Be phenomenon mostly rely on the critical rotation. We show that two-dimensional radiation transfer calculations are needed in rapid rotators to diagnose the stellar rotation more reliably.
A Highly Efficient Copper-Catalyzed Three-Component Synthesis of 4-Aminoquinazolines
Authors: Yang Lei , Luo Honghua , Sun Yan , Shi Zhenyu , Ni Kaidong , Li Fei , Chen Dongyin
Published: February 2017

A highly efficient copper-catalyzed one-pot protocol is developed for the synthesis of 4-aminoquinazolines from easily available 2-iodo- or 2-bromobenzimidamides, aldehydes, and sodium azide. This one-pot approach proceeds via consecutive copper-catalyzed SNAr substitution, reduction, cyclization, oxidation and tautomerization. The corresponding target products (26 examples) are obtained in 50–90% yield.
Revision of the Structure and Total Synthesis of Topsentin C
Authors: Golantsov Nikita , Festa Alexey , Varlamov Alexey , Voskressensky Leonid
Published: February 2017

An efficient synthetic approach to access (indol-3-yl)ethane-1,2-diamines with a protecting group at the indole N atom from readily available 3-(2-nitrovinyl)indoles is reported. This approach includes solvent-free conjugate addition of O-pivaloylhydroxylamines to 1-Boc-3-(2-nitrovinyl)indoles followed by mild reduction of the adducts. The obtained (indol-3-yl)ethane-1,2-diamines are convenient synthetic precursors for several classes of marine alkaloids. The first total synthesis of racemic topsentin C, a secondary metabolite from Hexadella sp., based on this approach is reported. The initially proposed structure for topsentin C has been revised.
Validation of the 36-item version of the WHO Disability Assessment Schedule 2.0 (WHODAS 2.0) for assessing women's disability and functioning associated with maternal morbidity
Authors: Silveira Carla , Parpinelli Mary Angela , Pacagnella Rodolfo Carvalho , Andreucci Carla Betina , Angelini Carina Robles , Ferreira Elton Carlos , Cecatti José Guilherme ,   the COMMAG study group
Published: February 2017

Objective To validate the translation and adaptation to Brazilian Portuguese of 36 items from the World Health Organizaton Disability Assessment Schedule 2.0 (WHODAS 2.0), regarding their content and structure (construct), in a female population after pregnancy.

Methods This is a validation of an instrument for the evaluation of disability and functioning and an assessment of its psychometric properties, performed in a tertiary maternity and a referral center specialized in high-risk pregnancies in Brazil. A sample of 638 women in different postpartum periods who had either a normal or a complicated pregnancy was included. The structure was evaluated by exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), while the content and relationships among the domains were assessed through Pearson's correlation coefficient. The sociodemographic characteristics were identified, and the mean scores with their standard deviations for the 36 questions of the WHODAS 2.0 were calculated. The internal consistency was evaluated byCronbach's α.

Results Cronbach's α was higher than 0.79 for both sets of questons of the questionnaire. The EFA and CFA for the main 32 questions exhibited a total variance of 54.7% (Kaiser-Meyer-Olkin [KMO] measure of sampling adequacy =  0.934; p < 0.001) and 53.47% (KMO = 0.934; p < 0.001) respectively. There was a significant correlation among the 6 domains (r = 0.571–0.876), and a moderate correlation among all domains (r = 0.476–0.694).

Conclusion The version of the WHODAS 2.0 instrument adapted to Brazilian Portuguese showed good psychometric properties in this sample, and therefore could be applied to populations of women regarding their reproductive history.
Upper Limb Functionality and Quality of Life in Women with Five-Year Survival after Breast Cancer Surgery
Authors: Recchia Thaís Lunardi , Prim Amably Cristiny , Luz Clarissa Medeiros da
Published: February 2017

Objective To evaluate the correlation between upper limb functionality and quality of life in women with five-year survival following breast cancer surgical treatment. The secondary objective was to evaluate the function of the ipsilateral upper limb and the quality of life in relation to the type of surgery and the presence of pain.

Methods The Disabilities of Arm, Shoulder and Hand (DASH), and the Functional Assessment of Cancer Therapy – Breast plus Arm Morbidity (FACTB + 4) questionnaires were used to evaluate upper limb function and quality of life respectively. Data distribution was verified by the Shapiro-Wilk test. Pearson's correlation coefficient was used for the parametric variables, and Spearman's rank correlation coefficient was used for the distribution of non-parametric variables. The statistical significance was set at 5% (p < 0.05).

Results The study included 30 patients, with a mean age of 51.23 (±8.72) years. The most common complications were: pain (50%), adherence (33.3%), and nerve lesion (20.0%). There was a moderate negative correlation between the instruments DASH and FACTB + 4 (total score), r = -0.634, and a strong negative correlation between the DASH and the FACTB + 4 arm subscale, r = -0.829. The scores of both questionnaires showed significant difference on the manifestation of pain. However, there was no significant difference found when comparing the scores considering the type of surgery performed.

Conclusions Five years after surgery, the patients showed regular functionality levels on the ipsilateral upper limb and decreased quality of life, especially in the group manifesting pain.
Predictors of cesarean delivery in pregnant women with gestational diabetes mellitus
Authors: Gascho Carmem Luiza Lucht , Leandro Danieli Mayumi Kimura , Ribeiro e Silva Thiago , Silva Jean Carl
Published: February 2017

Purpose The aim of this study was to evaluate which risk factors may lead patients with gestational diabetes mellitus to cesarean delivery.

Methods This was a retrospective, descriptive study. The subjects of the study were pregnant women with gestational diabetes mellitus attending a public maternity hospital in the south of Brazil. The primary outcomes assessed were based on maternal and fetal characteristics. The data were correlated using an odds ratio (OR) with a 95% confidence interval (95%CI), calculated using multinomial logistic regression.

Results A total of 392 patients with gestational diabetes mellitus were analyzed, and 57.4% of them had cesarean deliveries. Among the maternal characteristics, the mean age of the patients and the pregestational body mass index were greater when a cesarean delivery was performed (p = 0.029 and p < 0.01 respectively). Gestational age at birth, newborn weight, weight class according to gestational age, and Apgar score were not significant. The analysis of the OR showed that the chance of cesarean delivery was 2.25 times (95%CI = 1.49–2.39) greater if the pregnant woman was obese, 4.6 times (95%CI = 3.017–7.150) greater if she was a primigravida, and 5.2 times (95%CI = 2.702–10.003) greater if she had a previous cesarean delivery. The other parameters analyzed showed no differences.

Conclusion The factors that led to an increase in the occurrence of cesarean deliveries included history of a prior cesarean section, first pregnancy, and obesity.
Resolving Tussles in Service Automation Deployments: Service Automation at Blue Cross Blue Shield North Carolina (BCBSNC)
Authors: Dunlap Rod , Lacity Mary
Published: February 2017

This teaching case study provides a rich and realistic story of automating knowledge work within the context of a large, non-profit company. As an early pioneer in robotic process automation that built their own tool, the automation team at Blue Cross Blue Shield North Carolina (BCBSNC) sought to improve business performance through automation, which they accomplished in the form of a triple digit return on investment. However, BCBSNC managers had to mitigate the consequences of such success, such as deciding how to deal with redundant staff in an organization that values its employees and how to evaluate the work of the retained staff whose jobs became more challenging after automation. This case offers an opportunity to diagnose and to prescribe practices for resolving automation tussles among organizational stakeholders, including senior management vs middle managers, IT departments vs business operations, management vs labor, and ultimately man vs machine.
On the mixing enhancement in annular flows
Authors: Moradi H. V. , Floryan J. M.
Published: February 2017

The potential for mixing enhancement associated with the use of axisymmetric ribs in annular flows has been analyzed. The enhancement relies on the use of streamwise vortices produced by the centrifugal instability. Conditions leading to the formation of such vortices have been established for a wide range of geometric parameters of interest using linear stability theory. It has been demonstrated that vortices can be formed only in the presence of ribs with O(1) wavelengths. Slopes of the bounding walls in the case of the long wavelength ribs are too small to create centrifugal forces sufficient for flow destabilization. In the case of short wavelength ribs, the slopes become excessively large, resulting in the stream moving away from the wall and becoming rectilinear and, thus, reducing the magnitude of the centrifugal force field. It has been shown that decreasing the annulus’ radius reduces the critical Reynolds number when ribs are placed at the inner cylinder but increases when the ribs are placed at the outer cylinder. The onset of the shear-driven instability has been investigated as the resulting travelling waves may interfere with the formation of vortices. It has been shown that the axisymmetric waves play the critical role for annuli with large radii while the spiral waves play the critical role for annuli with small radii. The ribs always reduce the critical Reynolds number for the travelling waves when compared with the onset conditions for smooth annuli. The conduit geometries giving preference to the formation of vortices while avoiding creation of the travelling waves have been identified. It is demonstrated that predictions of flow characteristics determined through the analysis of sinusoidal ribs provide a good approximation of the flow response to ribs of arbitrary shape.
Efficient stochastic simulation of biochemical reactions with noise and delays
Authors: Thanh Vo Hong , Zunino Roberto , Priami Corrado
Published: February 2017

The stochastic simulation algorithm has been used to generate exact trajectories of biochemical reaction networks. For each simulation step, the simulation selects a reaction and its firing time according to a probability that is proportional to the reaction propensity. We investigate in this paper new efficient formulations of the stochastic simulation algorithm to improve its computational efficiency. We examine the selection of the next reaction firing and reduce its computational cost by reusing the computation in the previous step. For biochemical reactions with delays, we present a new method for computing the firing time of the next reaction. The principle for computing the firing time of our approach is based on recycling of random numbers. Our new approach for generating the firing time of the next reaction is not only computationally efficient but also easy to implement. We further analyze and reduce the number of propensity updates when a delayed reaction occurred. We demonstrate the applicability of our improvements by experimenting with concrete biological models.
Proton implantation for electrical insulation of the InGaAs/InAlAs superlattice material used in 8–15 μm-emitting quantum cascade lasers
Authors: Kirch J. D. , Kim H. , Boyle C. , Chang C.-C. , Mawst L. J. , Lindberg D. , Earles T. , Botez D. , Helm M. , von Borany J. , Akhmadaliev S. , Böttger R. , Reyner C.
Published: February 2017

We demonstrate the conversion of lattice-matched InGaAs/InAlAs quantum-cascade-laser (QCL) active-region material into an effective current-blocking layer via proton implantation. A 35-period active region of an 8.4 μm-emitting QCL structure was implanted with a dose of 5 × 1014 cm−2 protons at 450 keV to produce a vacancy concentration of ∼1019 cm−3. At room temperature, the sheet resistance, extracted from the Hall measurements, increases by a factor of ∼240 with respect to that of an unimplanted material. Over the 160–320 K temperature range, the activation energy of the implanted-material Hall sheet-carrier density is 270 meV. The significant increase in room-temperature sheet resistance indicates that upon implantation deep carrier traps have been formed in the InAlAs layers of the superlattice. Fabricated mesas show effective current blocking, at voltages ≥10 V, up to at least 350 K. Thus, the implanted InGaAs/InAlAs superlattices are highly resistive to at least 350 K heat sink temperature. Such implanted material should prove useful for effective current confinement in 8–15 μm-emitting InP-based single-emitter QCL structures as well as in resonant leaky-wave coupled phase-locked arrays of QCLs.
Early detection of clinical mastitis from electrical conductivity data in an automatic milking system
Authors: Khatun Momena , Clark Cameron E. F. , Lyons Nicolas A. , Thomson Peter C. , Kerrisk Kendra L. , García Sergio C.
Published: February 2017

Mastitis adversely affects profit and animal welfare in the Australian dairy industry. Electrical conductivity (EC) is increasingly used to detect mastitis, but with variable results. The aim of the present study was to develop and evaluate a range of indexes and algorithms created from quarter-level EC data for the early detection of clinical mastitis at four different time windows (7 days, 14 days, 21 days, 27 days). Historical longitudinal data collected (4-week period) for 33 infected and 139 healthy quarters was used to compare the sensitivity (Se; target >80%), specificity (Sp; target >99%), accuracy (target >90%) and timing of ‘alert’ by three different approaches. These approaches involved the use of EC thresholds (range 7.5– 10 mS/cm), testing of over 250 indexes (created ad hoc), and a statistical process-control method. The indexes were developed by combining factors (and levels within each factor), such as conditional rolling average increase, percentage of variation, mean absolute deviation, mean error %; infected to non-infected ratio, all relative to the rolling average (3–9 data points) of either the affected quarter or the average of the four quarters. Using EC thresholds resulted in Se, Sp and accuracy ranging between 47% and 92%, 39% and 92% and 51% and 82% respectively (threshold 7.5 mS/cm performed best). The six highest performing indexes achieved Se, Sp and accuracy ranging between 68% and 84%, 60% and 85% and 56% and 81% respectively. The statistical process-control approach did not generate accurate predictions for early detection of clinical mastitis on the basis of EC data. Improved Sp was achieved when the time window before treatment was reduced regardless of the test approach. We concluded that EC alone cannot provide the accuracy required to detect infected quarters. Incorporating other information (e.g. milk yield, milk flow, number of incomplete milking) may increase accuracy of detection and ability to determine early onset of mastitis.
Facultative crassulacean acid metabolism (CAM) in four small C3 and C4 leaf-succulents
Authors: Winter Klaus , Holtum Joseph A. M.
Published: February 2017

Measurements of whole-plant gas exchange and titratable acidity demonstrate that the Australian native species Anacampseros australiana J.M.Black (Anacampserotaceae), Crassula sieberiana (Schult. & Schult.f.) Druce (Crassulaceae) and Portulaca australis Endl. (Portulacaceae) and the widespread naturalised tropical exotic, Portulaca pilosa L., exhibit facultative crassulacean acid metabolism (CAM). In well-watered plants, net CO2 uptake was restricted to the daylight hours and occurred via the C3 pathway (A. australiana and C. sieberiana) or the C4 pathway (P. australis and P. pilosa). Leaves of well-watered plants did not accumulate titratable acidity during the night. Following drought treatment, CO2 uptake in the light by shoots decreased markedly, nocturnal gas-exchange shifted from net CO2 loss to a CAM-type pattern that included net CO2 uptake, and leaves acidified at night. Nocturnal CO2 uptake by shoots and leaf acidification were most pronounced in A. australiana and least so in C. sieberiana. The induction of dark CO2 uptake and tissue acidification was fully reversible in all four species: upon rewatering, nocturnal CO2 uptake and acidification ceased and the rates of CO2 incorporation in the light were restored. We suggest that, hitherto considered relatively exceptional globally, facultative CAM may be more common than previously suspected, particularly among the generally small ephemeral leaf-succulents that characterise Australia’s succulent flora.
Localisation of stem cell factor, stanniocalcin-1, connective tissue growth factor and heparin-binding epidermal growth factor in the bovine uterus at the time of blastocyst formation
Authors: Muñoz M. , Martin D. , Carrocera S. , Alonso-Guervos M. , Mora M. I. , Corrales F. J. , Peynot N. , Giraud-Delville C. , Duranthon V. , Sandra O. , Gómez E.
Published: February 2017

Early embryonic losses before implantation account for the highest rates of reproductive failure in mammals, in particular when in vitro-produced embryos are transferred. In the present study, we used molecular biology techniques (real-time quantitative polymerase chain reaction), classical immunohistochemical staining coupled with confocal microscopy and proteomic analysis (multiple reaction monitoring and western blot analysis) to investigate the role of four growth factors in embryo–uterine interactions during blastocyst development. Supported by a validated embryo transfer model, the study investigated: (1) the expression of stem cell factor (SCF), stanniocalcin-1 (STC1), connective tissue growth factor (CTGF) and heparin-binding epidermal growth factor-like growth factor (HB-EGF) in bovine uterine fluid; (2) the presence of SCF, STC1, CTGF and HB-EGF mRNA and protein in the bovine endometrium and embryos; and (3) the existence of reciprocal regulation between endometrial and embryonic expression of SCF, STC1, CTGF and HB-EGF. The results suggest that these growth factors most likely play an important role during preimplantation embryo development in cattle. The information obtained from the present study can contribute to improving the performance of in vitro culture technology in cattle and other species.
Vpx overcomes a SAMHD1-independent block to HIV reverse transcription that is specific to resting CD4 T cells
Authors: Baldauf Hanna-Mari , Stegmann Lena , Schwarz Sarah-Marie , Ambiel Ina , Trotard Maud , Martin Margarethe , Burggraf Manja , Lenzi Gina M. , Lejk Helena , Pan Xiaoyu , Fregoso Oliver I. , Lim Efrem S. , Abraham Libin , Nguyen Laura A. , Rutsch Frank , König Renate , Kim Baek , Emerman Michael , Fackler Oliver T. , Keppler Oliver T.
Published: February 2017

Significance

HIV infection can be restricted by different host cell proteins. One such restriction factor is SAM domain and HD domain-containing protein 1 (SAMHD1), a triphosphohydrolase that cleaves dNTPs, which are required for HIV reverse transcription. The accessory lentiviral protein X (Vpx) from simian immunodeficiency viruses (SIV) of sooty mangabeys and rhesus macaques or from HIV-2 degrade SAMHD1. Here we show that Vpx proteins from SIVs of red-capped mangabeys and mandrills enhance HIV infection of resting CD4 T cells, but not macrophages, without affecting levels of either SAMHD1 or dNTPs. These Vpx proteins overcome a previously unrecognized SAMHD1-independent, cell-type–specific restriction at the level of reverse transcription and highlight the plasticity of lentiviruses to counteract the innate immune system.
Structural insights into the activation mechanism of dynamin-like EHD ATPases
Authors: Melo Arthur Alves , Hegde Balachandra G. , Shah Claudio , Larsson Elin , Isas J. Mario , Kunz Séverine , Lundmark Richard , Langen Ralf , Daumke Oliver
Published: February 2017

Significance

Eps15 (epidermal growth factor receptor pathway substrate 15)-homology domain containing proteins (EHDs) are molecular machines that use the energy of ATP binding and ATP hydrolysis to remodel shallow membranes into highly curved membrane tubules. This activity is required in many cellular membrane trafficking pathways. In this work, we have determined a high-resolution structure of an EHD machine in the active state. The structure indicates how EHDs assemble at the membrane surface into ring-like scaffolds that deform the underlying membrane. By comparing this active state with a previously determined autoinhibited conformation, we can deduce the mechanistic details how recruitment of EHDs to membranes is regulated. A comparison with other membrane-associated molecular machines reveals commonalities and differences in the activation mechanism.
Activation mechanism of the G protein-coupled sweet receptor heterodimer with sweeteners and allosteric agonists
Authors: Kim Soo-Kyung , Chen Yalu , Abrol Ravinder , Goddard William A. , Guthrie Brian
Published: February 2017

Significance

We report a dynamical study of sweet receptor heterodimer, for which there are abundant data for various sweeteners. Because there is no crystal structure of a complete G protein-coupled receptor (GPCR) dimer of class C, we predicted the three-dimensional structure and carried out molecular dynamics with and without the sweetener agonists. We found that binding the sweetener induces major conformational changes during which the transmembrane domain (TMD) transforms from the TMD 56 interface to the TMD 6 interface, which is consistent with biophysical studies on activation of metabotropic glutamate receptor 2 homodimers, also class C. These results provide insights for how GPCRs are activated, which may have a major impact on understanding activation of other GPCR therapeutic targets.
In Vitro Inhibition of Saprolegnia sp. by an Antifungal Peptide from Pseudomonas protegens XL03
Authors: Wang Feifei , Zhang Qizhong
Published: February 2017

Saprolegniasis, a fungal fish disease, is an important challenge in the aquaculture industry. To find a natural agent to control saprolegniasis, an anti-Saprolegnia bacterium, named XL03, was isolated from the sediment of the Baimang River in Xili, Guangzhou, China. The bacterium was identified as Pseudomonas protegens by means of 16S rDNA gene sequence and its fluorescent character. Saprolegnia sp. was used to evaluate the antifungal activity of the P. protegens strain XL03. The cell-free disruption supernatant (CFDS) showed an antifungal zone of 19.34 ± 1.20 mm against the Saprolegnia hyphae on the potato dextrose agar (20% potato extract, 2% glucose, 2% agar) medium plate and depicted a minimum inhibitory concentration (MIC = 12.5 mg/mL) against the Saprolegnia spore germination in vitro. To purify the antifungal substance from the CFDS, ammonium sulphate precipitation, gel filtration, and ion-exchange chromatography were applied, and the purified peptide exhibited a single band at molecular weight about 58 kDa on a SDS-PAGE gels. Furthermore, the MIC of the purified peptide was identified as 0.0625 mg/mL against Saprolegnia spores, and the activity of peptide showed thermal stability between 30°C and 60°C but retained activity only in a narrow pH range of 5.0–9.0. These findings demonstrate that P. protegens strain XL03 has the potential to be used in biocontrol of saprolegniasis in aquaculture.
Soreness‐related changes in three‐dimensional running biomechanics following eccentric knee extensor exercise
Authors: Paquette Max R. , Peel Shelby A. , Schilling Brian K. , Melcher Dan A. , Bloomer Richard J.
Published: February 2017

Runners often experience delayed onset muscle soreness (DOMS), especially of the knee extensors, following prolonged running. Sagittal knee joint biomechanics are altered in the presence of knee extensor DOMS but it is unclear how muscle soreness affects lower limb biomechanics in other planes of motion. The purpose of this study was to assess the effects of knee extensor DOMS on three‐dimensional (3D) lower limb biomechanics during running. Thirty‐three healthy men (25.8 ± 6.8 years; 84.1 ± 9.2 kg; 1.77 ± 0.07 m) completed an isolated eccentric knee extensor damaging protocol to elicit DOMS. Biomechanics of over‐ground running at a set speed of 3.35 m s−1±5% were measured before eccentric exercise (baseline) and, 24 h and 48 h following exercise in the presence of knee extensor DOMS. Knee flexion ROM was reduced at 48 h (P = 0.01; d = 0.26), and peak knee extensor moment was reduced at 24 h (P = 0.001; d = 0.49) and 48 h (P < 0.001; d = 0.68) compared to baseline. Frontal and transverse plane biomechanics were unaffected by the presence of DOMS (P > 0.05). Peak positive ankle and knee joint powers and, peak negative knee joint power were all reduced from baseline to 24 h and 48 h (P < 0.05). These findings suggest that knee extensor DOMS greatly influences sagittal knee joint angular kinetics and, reduces sagittal power production at the ankle joint. However, knee extensor DOMS does not affect frontal and transverse plane lower limb joint biomechanics during running.
Liberalism and shadow interventionism in post-revolutionary Georgia (2003–2012)
Authors: Rekhviashvili Lela , Polese Abel
Published: February 2017

This article looks at the informal governance practice of Georgia’s post-revolution (2003-2012) reformers. Empirically, we argue that the deployment of informal governance strategies became necessary for the Georgian government precisely because its official liberal reform course was politically constraining and incapacitated it from coping with the social costs of marketization and political-economic crisis. The analysed case, we submit, has major implications for theories of governance and informality. As it stands now, the literature is predominantly preoccupied with improvements in the state’sinstitutional quality. The Georgian case, in contrast, highlights the importance ofinstitutional design. Utilizing perspectives from Polanyian institutionalist analysis, we problematise the ongoing propagation of market-enhancing institutional design and underline the importance of marketconstraining and social regulation. Arguing that reliance on informality cannot be reduced to profit seeking, or even to formal systemic institutional weakness, we attempt to shift the focus of the literature on governance and institutions from quality of institutional performance back to the once dominant question of development studies, namely the content of institutional design.
Cysteine residues in a yeast viral A/B toxin crucially control host cell killing via pH-triggered disulfide rearrangements
Authors: Suzuki Yutaka , Schwartz Sara L. , Mueller Nina C. , Schmitt Manfred J.
Published: February 2017

K28 is a viral A/B protein toxin that intoxicates yeast and fungal cells by endocytosis and retrograde transport to the endoplasmic reticulum (ER). Although toxin translocation into the cytosol occurs on the oxidized α/β heterodimer, the precise mechanism of how the toxin crosses the ER membrane is unknown. Here we identify pH-triggered, toxin-intrinsic thiol rearrangements that crucially control toxin conformation and host cell killing. In the natural habitat and low-pH environment of toxin-secreting killer yeasts, K28 is structurally stable and biologically active as a disulfide-bonded heterodimer, whereas it forms inactive disulfide-bonded oligomers at neutral pH that are caused by activation and thiol deprotonation of β-subunit cysteines. Because such pH increase reflects the pH gradient during compartmental transport within target cells, potential K28 oligomerization in the ER lumen is prevented by protein disulfide isomerase. In addition, we show that pH-triggered thiol rearrangements in K28 can cause the release of cytotoxic α monomers, suggesting a toxin-intrinsic mechanism of disulfide bond reduction and α/β heterodimer dissociation in the cytosol.
Angel: a new large-scale machine learning system
Authors: Jiang Jie , Yu Lele , Jiang Jiawei , Liu Yuhong , Cui Bin
Published: February 2017

Machine Learning (ML) techniques now are ubiquitous tools to extract structural information from data collections. With the increasing volume of data, large-scale ML applications require an efficient implementation to accelerate the performance. Existing systems parallelize algorithms through either data parallelism or model parallelism. But data parallelism cannot obtain good statistical efficiency due to the conflicting updates to parameters while the performance is damaged by global barriers in model parallel methods. In this paper, we propose a new system, named Angel, to facilitate the development of large-scale ML applications in production environment. By allowing concurrent updates to model across different groups and scheduling the updates in each group, Angel can achieve a good balance between hardware efficiency and statistical efficiency. Besides, Angel reduces the network latency by overlapping the parameter pulling and update computing and also utilizes the sparseness of data to avoid the pulling of unnecessary parameters. We also enhance the usability of Angel by providing a set of efficient tools to integrate with application pipelines and provisioning efficient fault tolerance mechanisms. We conduct extensive experiments to demonstrate the superiority of Angel.
Metal nanoparticles induced photocatalysis
Authors: Liu Lequan , Zhang Xinnan , Yang Lufeng , Ren Liteng , Wang Defa , Ye Jinhua
Published: February 2017

Photocatalysis induced by light absorption of metal nanoparticles (NPs) has emerged as a promising strategy for exploiting efficient visible-light-responsive composites for solar-energy conversion. In this review, we first introduce the light absorption of metal NPs and the mechanisms proposed in metal-induced photocatalysis (MIP). Then, its applications in water splitting, artificial photosynthesis and inert molecular activation are summarized. To address the challenge of low efficiency in this field, strategies in promoting catalytic activity are reviewed, and particular attention is paid to the particle-size effect of metal. Finally, the challenges and possible development directions of MIP are briefly discussed.
Outcomes of Women With High-Grade and Low-Grade Advanced-Stage Serous Epithelial Ovarian Cancer
Authors: Gockley Allison , Melamed Alexander , Bregar Amy J. , Clemmer Joel T. , Birrer Michael , Schorge John O. , del Carmen Marcela G. , Rauh-Hain J. Alejandro
Published: February 2017

OBJECTIVE:

To compare outcomes of women with advanced-stage low-grade serous ovarian cancer and high-grade serous ovarian cancer and identify factors associated with survival among patients with advanced-stage low-grade serous ovarian cancer.

METHODS:

A retrospective study of patients diagnosed with grade 1 or 3, advanced-stage (stage IIIC and IV) serous ovarian cancer between 2003 and 2011 was undertaken using the National Cancer Database, a large administrative database. The effect of grade on survival was analyzed using the Kaplan-Meier method. Factors predictive of outcome were compared using the Cox proportional hazards model. Among women with low-grade serous ovarian cancer, propensity score matching was used to compare all-cause mortality among similar women who underwent chemotherapy and lymph node dissection and those who did not.

RESULTS:

A total of 16,854 (95.7%) patients with high-grade serous ovarian cancer and 755 (4.3%) patients with low-grade serous ovarian cancer were identified. Median overall survival was 40.7 months among high-grade patients and 90.8 months among women with low-grade tumors (P<.001). Among patients with low-grade serous ovarian cancer in the propensity score-matched cohort, the median overall survival was 88.2 months among the 140 patients who received chemotherapy and 95.9 months among the 140 who did not receive chemotherapy (P=.7). Conversely, in the lymph node dissection propensity-matched cohort, median overall survival was 106.5 months among the 202 patients who underwent lymph node dissection and 58 months among the 202 who did not (P<.001).

CONCLUSION:

When compared with high-grade serous ovarian cancer, low-grade serous ovarian cancer is associated with improved survival. In patients with advanced-stage low-grade serous ovarian cancer, lymphadenectomy but not adjuvant chemotherapy was associated with improved survival.
Filled Prescriptions for Opioids After Vaginal Delivery
Authors: Jarlenski Marian , Bodnar Lisa M. , Kim Joo Yeon , Donohue Julie , Krans Elizabeth E. , Bogen Debra L.
Published: February 2017

OBJECTIVE:

To estimate the prevalence of filled opioid prescriptions after vaginal delivery.

METHODS:

We conducted a retrospective cohort study of 164,720 Medicaid-enrolled women in Pennsylvania who delivered a liveborn neonate vaginally from 2008 to 2013, excluding women who used opioids during pregnancy or who had an opioid use disorder. We assessed overall filled prescriptions as well as filled prescriptions in the presence or absence of the following pain-inducing conditions: bilateral tubal ligation, perineal laceration, or episiotomy. Outcomes included a binary measure of whether a woman had any opioid prescription fill 5 days or less after delivery and, among those women, a second opioid prescription fill 6–60 days after delivery. Among women with no coded pain-inducing conditions at delivery, we used multivariable logistic regression with standard errors clustered to account for within-hospital correlation to assess the association between patient characteristics and odds of a filled opioid prescription.

RESULTS:

Twelve percent of women (n=18,131) filled an outpatient opioid prescription 5 days or less after vaginal delivery; among those women, 14% (n=2,592, or 1.6% of the total) filled a second opioid prescription 6–60 days after delivery. Of the former, 5,110 (28.2%) had one or more pain-inducing conditions. Predictors of filled opioid prescriptions with no observed pain-inducing condition at delivery included tobacco use (adjusted odds ratio [OR] 1.3, 95% confidence interval [CI] 1.2–1.4) and a mental health condition (adjusted OR 1.3, 95% CI 1.2–1.4). Having a diagnosis of substance use disorder other than opioid use disorder was not associated with filling an opioid prescription 5 days or less after delivery, but was associated with having a second opioid prescription 6–60 days after delivery (adjusted OR 1.4, 95% CI 1.2–1.6).

CONCLUSION:

More than 1 in 10 Medicaid-enrolled women fill an outpatient opioid prescription after vaginal delivery. National opioid-prescribing recommendations for common obstetrics procedures such as vaginal delivery are warranted.
Pulmonary Hypertension in Pregnancy
Authors: Meng Marie-Louise , Landau Ruth , Viktorsdottir Olof , Banayan Jennifer , Grant Tamila , Bateman Brian , Smiley Richard , Reitman Elena
Published: February 2017

OBJECTIVE:

To identify whether pregnancy outcomes vary by etiology and severity of pulmonary hypertension and whether contemporary therapies influence outcomes.

METHODS:

A retrospective review of medical records at four academic institutions was conducted to identify pregnant women with pulmonary hypertension (2001–2015). International Classification of Diseases, 9th Revision codes for pulmonary hypertension and pregnancy were used to identify potential participants. Medical records were abstracted for demographics, management, and outcomes. Women were classified according to the 2013 World Health Organization (WHO) pulmonary hypertension classification groups 1–5. Mild pulmonary hypertension was defined as a mean pulmonary artery pressure 25–49 mm Hg and severe pulmonary hypertension as mean pulmonary artery pressure 50 mm Hg or greater or systolic pulmonary artery pressure 70 mm Hg or greater. Descriptive statistics were used to compare outcomes.

RESULTS:

Forty-nine women were identified. Mortality rate was 16% (n=8/49); all deaths occurred postpartum, and seven of eight deaths occurred in women with WHO group 1 pulmonary hypertension (mortality rate 23%, n=7/30). Of the women who had documented live births with known mode of delivery (n=41), mortality was 4 of 22 among women with severe pulmonary hypertension and 1 of 19 among women with mild pulmonary hypertension. Mortality among women who delivered by cesarean was 4 of 22 and was 1 of 19 among women who delivered vaginally. Neuraxial anesthesia was performed in 20 of 22 cesarean and 17 of 19 vaginal deliveries with no anesthesia-related adverse events. Women with severe pulmonary hypertension needed more advanced therapies such as inotropes, pulmonary vasodilators, and extracorporeal membrane oxygenation than did women with mild pulmonary hypertension, 19 of 26 compared with 7 of 22. Preterm delivery was more common in women with severe compared with mild pulmonary hypertension, 19 of 23 compared with 8 of 17. There was one 25-week intrauterine fetal demise, but no neonatal deaths.

CONCLUSION:

In this large series of pulmonary hypertension in pregnancy, mortality remained high despite advanced therapies. Maternal mortality was specific to WHO group 1 pulmonary hypertension and possibly associated with severe pulmonary hypertension. In selected patients with a favorable prognosis for vaginal birth, a trial of labor can be considered.
Risk Factors for Postcesarean Maternal Infection in a Trial of Extended-Spectrum Antibiotic Prophylaxis
Authors: Boggess Kim A. , Tita Alan , Jauk Victoria , Saade George , Longo Sherri , Clark Erin A. S. , Esplin Sean , Cleary Kristin , Wapner Ronald , Letson Kelli , Owens Michelle , Blackwell Sean , Beamon Carmen , Szychowski Jeffrey M. , Andrews William ,   for the Cesarean Section Optimal Antibiotic Prophylaxis Trial Consortium
Published: February 2017

OBJECTIVE:

To identify maternal clinical risk factors for postcesarean maternal infection in a randomized clinical trial of preincision extended-spectrum antibiotic prophylaxis.

METHODS:

We conducted a planned secondary analysis of a randomized clinical trial. Patients were 24 weeks of gestation or greater and delivered by cesarean after a minimum of 4 hours of ruptured membranes or labor. All participants received standard preincision prophylaxis and were randomized to receive azithromycin or placebo. The primary outcome for this analysis is maternal infection: a composite outcome of endometritis, wound infection (superficial or deep), or other infections occurring up to 6 weeks postpartum. Maternal clinical characteristics associated with maternal infection, after controlling for azithromycin assignment, were identified. These maternal factors were included in a multivariable logistic regression model for maternal infection.

RESULTS:

Of 2,013 patients, 1,019 were randomized to azithromycin. Overall, 177 (8.8%) had postcesarean maternal infection. In the final adjusted model, compared with the reference groups, women of black race–ethnicity, with a nontransverse uterine incision, with duration of membrane rupture greater than 6 hours, and surgery duration greater than 49 minutes, were associated higher odds of maternal infection (all with adjusted odds ratios [ORs] of approximately 2); azithromycin was associated with lower odds of maternal infection (adjusted OR 0.4, 95% confidence interval 0.3–0.6).

CONCLUSION:

Despite preincision azithromycin-based extended-spectrum antibiotic prophylaxis, postcesarean maternal infection remains a significant source of morbidity. Recognition of risk factors may help guide innovative prevention strategies.

CLINICAL TRIAL REGISTRATION:

ClinicalTrials.gov, https://clinicaltrials.gov, NCT012235546.