bluuebunny/crossref_metadata_2025 huggingface dataset:
High‐resolution records of climate change in arid eastern central Asia during MIS 3 (51 600–25 300 cal a BP) from Wulungu Lake, north‐western China
Authors: Zhang Xiaonan , Zhou Aifeng , Zhang Can , Hao Shengtun , Zhao Yongtao , An Chengbang
Published: August 2016

Detailed records of climate change during the Last Glaciation in arid central Asia are scarce. Here we present a sedimentological and geochemical record from Wulungu Lake in north‐western China, providing the first high‐resolution, continuous sedimentary records in this region covering Marine Isotope Stage (MIS) 3 (51 600–25 300 cal a BP). High lake power (end‐member 2 values) and bioproductivity concurrent with low terrigenous clastic input unanimously indicate high lake water levels during 46 180–39 770, 31 680–30 080 and 27 780–26 540 cal a BP, and moderately wet conditions during 51 600–46 180 and 39 770–31 680 cal a BP. The lake attained its lowest water levels after 30 080 cal a BP. Few dry events characterized by high pool power (end‐member 3 values) and terrigenous input are documented for the studied interval and three of them are correlative with Heinrich events 5–3. Our study supports the hypothesis for a positive Northern Hemisphere July insolation anomaly which increased the temperature gradient between low and high latitudes, increasing the strength of Westerlies and increasing sea surface temperatures in the North Atlantic, resulting in more moisture transported to arid central Asian by Westerlies.
A comparison of pollen extraction methods confirms dense‐media separation as a reliable method of pollen preparation
Authors: Campbell J. F. E. , Fletcher W. J. , Hughes P. D. , Shuttleworth E. L.
Published: August 2016

Palynology is a crucial proxy for understanding Quaternary environmental change. A range of laboratory preparation techniques has been developed to deal with the extraction of pollen in different sedimentary contexts. Here, we present a comparison of the conventional hydrofluoric acid method and the dense‐media separation method using sodium polytungstate. We examine pollen, non‐pollen palynomorphs (NPPs) and microcharcoal by undertaking parallel preparation and counting of 30 paired samples from three sites in the Middle Atlas Mountains, Morocco, with contrasting environmental and sedimentary conditions. Differences between microfossil counts are assessed visually and statistically, using ANOVA and linear regression. We observe that the typical offset between counts for the five most common pollen and NPPs produced by the two methods (µ = 1.6%, SD = 0.9%) is considerably smaller than the 95% uncertainty associated with the standard counting procedure (µ = 6.8%, SD = 2.7%). There is no statistically significant difference associated with the preparation methods, and no significant deviation from a linear relationship between the results obtained by the two methods. There are advantages and disadvantages to both methods in terms of preparation time and visual characteristics. This study confirms that results for pollen, NPPs and microcharcoal obtained by either preparation method can be directly compared.
The role of upper airway stimulation therapy in the multidisciplinary management approach of obstructive sleep apnea in the adult patient
Authors: Doghramji Karl , Boon Maurits
Published: August 2016

Upper airway stimulation therapy (UAS) is a novel and effective treatment modality for obstructive sleep apnea (OSA). It is indicated for patients who are intolerant to traditional forms of therapy such as CPAP, and who have moderate to severe disease. Its success also relies upon the absence of certain upper airway structural and functional abnormalities. Therefore, the implementation of UAS necessitates a comprehensive evaluation with the coordinated efforts of otolaryngologist and sleep specialist, utilizing the consultative input of various other specialists. This same collaborative process also underlies the successful long‐term followup care of patients following implantation surgery. Laryngoscope, 126:S9–S11, 2016
Maintain Spatial Heterogeneity, Maintain Biodiversity—A Seed Bank Study in a Grazed Alpine Fen Meadow
Authors: Xu Ling‐xiang , Cao Yu , Li Wei , Cheng Yu , Qin Tong‐chun , Zhou Yuan‐chang , Liu Fan
Published: August 2016

Wetland degradation is a source of anxiety and is more severe in cold regions than other areas. The soil seed bank acts as a propagule source for revegetation to affiliate the restoration of degraded wetlands. However, the effects of this approach are controversial and depend on the traits of the seed bank and its interactions with the environment. The seed bank in an alpine fen meadow was studied to determine its exact role in revegetation. The surveyed shore of a Tibetan lake, Gahai Lake, was divided into three sites under different levels of grazing pressure. Each site was separated into six transects along a water‐depth gradient to collect soil cores to determine the pattern of biodiversity through a germination experiment in a greenhouse. After an analysis of heterogeneity‐related diversity, partitioning of 58 discovered species indicated that 39.5 could be contributed to beta‐diversity, which was mainly contributed to water depth. Overgrazing (0.607 sheep unit/acre, November—March) decreased seed bank diversity in many respects, especially through decreasing spatial heterogeneity and homogenizing biota. A lightly grazed, well‐protected site had not only the highest beta‐diversity and species abundance but also the highest inter‐site species turnover rate compared with other sites under moderate grazing intensity. Despite the lack of target species, the seed bank serves as (i) a species‐rich pool; (ii) an extant legacy seed source for sustaining heterogeneity and floristic diversity; and (iii) an ecological indicator, and its effect can be reinforced by appropriate grazing practices (multiple intensity) and hydrological modifications. Copyright © 2016 John Wiley & Sons, Ltd.
The fractional natural decomposition method: theories and applications
Authors: Rawashdeh Mahmoud S.
Published: August 2016

In this paper, we propose a new method called the fractional natural decomposition method (FNDM). We give the proof of new theorems of the FNDM, and we extend the natural transform method to fractional derivatives. We apply the FNDM to construct analytical and approximate solutions of the nonlinear time‐fractional Harry Dym equation and the nonlinear time‐fractional Fisher's equation. The fractional derivatives are described in the Caputo sense. The effectiveness of the FNDM is numerically confirmed. Copyright © 2016 John Wiley & Sons, Ltd.
Modeling of Polyolefin Polymerization in Semibatch Slurry Reactors: Experiments and Simulations
Authors: Casalini Tommaso , Visscher Frans , Janssen Erik , Bertola Francesco , Storti Giuseppe , Morbidelli Massimo
Published: August 2016

In this work, a well‐known single‐particle model (the multigrain model) is applied to simulate size growth and morphology evolution of polyethylene particles obtained through a slurry phase, catalytic polymerization in semibatch reactor. The model explicitly accounts for diffusion limitations within the polymer particle and between the particle and the solvent, as well as void fraction variations due to the particle growth. Catalyst behavior is described assuming a two‐site model, a good compromise between accuracy and simplicity, along with a conventional kinetic scheme, whose kinetic parameters are determined by fitting the model predictions to the experimental data. Polymer molecular weight is evaluated from population balances, solved through the method of moments. The semibatch reactor is modeled by means of fundamental mass conservation equations. Simulations show that the proposed model is able to describe not only the polymer properties of interest but also the evolution of the average particle size, thus providing a comprehensive overview of the system behavior. The model is further validated through regression‐free simulation of additional sets of experimental data, including materials with a bimodal molar mass distribution: the good agreement also found in this case confirms the robustness of the model and the estimated parameter values.

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Chemie als Zukunftswissenschaft
Authors: Lindhorst Thisbe K.
Published: August 2016

Im Jahr 1867 gründete sich in Berlin die Deutsche Chemische Gesellschaft, die ältere der beiden Vorgängerorganisationen der Gesellschaft Deutscher Chemiker. Doch der Blick zurück reicht nicht aus, denn die Frage lautet: Was bringt die Zukunft uns und was bringen wir der Zukunft?
Hydrostatic pressure and muscarinic receptors are involved in the release of inflammatory cytokines in human bladder smooth muscle cells
Authors: Liang Zhou , Xin Wei , Qiang Liu , Xiang Cai , Bang‐Hua Liao , Jin Yang , De‐Yi Luo , Hong Li , Kun‐Jie Wang
Published: August 2016

Aims

Abnormal intravesical pressure results in a series of pathological changes. We investigated the effects of hydrostatic pressure and muscarinic receptors on the release of inflammatory cytokines in rat and human bladder smooth muscle cells (HBSMCs).

Methods

Animal model of bladder outlet obstruction was induced by urethra ligation. HBSMCs were subjected to elevated hydrostatic pressure and/or acetylcholine (Ach). Macrophage infiltration in the bladder wall was determined by immunohistochemical staining. The expression of inflammatory genes was measured by RT‐PCR, ELISA and immunofluorescence.

Results

In obstructed bladder, inflammatory genes and macrophage infiltration were remarkably induced. When HBSMCs were subjected to 200–300 cm H2O pressure for 2–24 h in vitro, the expressions of IL‐6 and RANTES were significantly increased. Hydrostatic pressure promoted the protein levels of phospho‐NFκB p65 and phospho‐ERK1/2 as well as muscarinic receptors. Moreover, NFκB or ERK1/2 inhibitors suppressed pressure‐induced inflammatory genes mRNA. When cells were treated with 1 μM acetylcholine for 6 h, a significant increase in IL‐6 mRNA expression was detected. Acetylcholine also enhanced pressure‐induced phospho‐NFκB p65 and IL‐6 protein expression. Additionally, pressure‐induced IL‐6 was partially suppressed by muscarinic receptors antagonists.

Conclusions

Hydrostatic pressure and muscarinic receptors were involved in the secretion of inflammatory cytokines in HBSMCs, indicating a pro‐inflammatory effect of the two factors in the pathological process of BOO.
Establishing stable time‐steps for DEM simulations of non‐collinear planar collisions with linear contact laws
Authors: Burns Shane J. , Hanley Kevin J.
Published: August 2016

The discrete element method, developed by Cundall and Strack, typically uses some variations of the central difference numerical integration scheme. However, like all explicit schemes, the scheme is only conditionally stable, with the stability determined by the size of the time‐step. The current methods for estimating appropriate discrete element method time‐steps are based on many assumptions; therefore, large factors of safety are usually applied to the time‐step to ensure stability, which substantially increases the computational cost of a simulation. This work introduces a general framework for estimating critical time‐steps for any planar rigid body subject to linear damping and forcing. A numerical investigation of how system damping, coupled with non‐collinear impact, affects the critical time‐step is also presented. It is shown that the critical time‐step is proportional to
if a linear contact model is adopted, where m and k represent mass and stiffness, respectively. The term which multiplies this factor is a function of known physical parameters of the system. The stability of a system is independent of the initial conditions. © 2016 The Authors. International Journal for Numerical Methods in Engineering Published by John Wiley & Sons Ltd.
Error estimates to smooth solutions of semi‐discrete discontinuous Galerkin methods with quadrature rules for scalar conservation laws
Authors: Huang Juntao , Shu Chi‐Wang
Published: August 2016

In this article, we focus on error estimates to smooth solutions of semi‐discrete discontinuous Galerkin (DG) methods with quadrature rules for scalar conservation laws. The main techniques we use are energy estimate and Taylor expansion first introduced by Zhang and Shu in (Zhang and Shu, SIAM J Num Anal 42 (2004), 641–666). We show that, with
(piecewise polynomials of degree k) finite elements in 1D problems, if the quadrature over elements is exact for polynomials of degree
, error estimates of
are obtained for general monotone fluxes, and optimal estimates of
are obtained for upwind fluxes. For multidimensional problems, if in addition quadrature over edges is exact for polynomials of degree
, error estimates of
are obtained for general monotone fluxes, and
are obtained for monotone and sufficiently smooth numerical fluxes. Numerical results validate our analysis. © 2016 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 33: 467–488, 2017
Prospective study of neuropathic pain after definitive surgery for extremity osteosarcoma in a pediatric population
Authors: Anghelescu Doralina L. , Steen Brenda D. , Wu Huiyun , Wu Jianrong , Daw Najat C. , Rao Bhaskar N. , Neel Michael D. , Navid Fariba
Published: August 2016

Background

Neuropathic pain (NP) after definitive surgery for extremity osteosarcoma (OS) has not been previously characterized. This study prospectively investigates the incidence, duration, and treatment of NP in limb sparing surgery and amputation groups.

Procedure

In patients treated for OS on a chemotherapy and definitive surgery (limb sparing vs. amputation) protocol (OS08), we prospectively collected the following data: (i) demographical data (age, sex, race); (ii) NP time of onset and duration; and (iii) dose (starting, maximum) and duration of gabapentin, amitriptyline, and methadone treatment.

Results

Thirty‐seven patients underwent 38 definitive surgeries: limb sparing (26, 68.4%) or amputations (12, 31.6%). Localization included lower extremity (30, 81%), upper extremity (6, 16%), or pelvis (1, 3%). Thirty patients (81%) developed NP and 26 of them required NP‐specific medications (87.7%). The mean [standard deviation (SD)] duration of NP was 6.5 weeks (7.2) (median 4.4, range 0.3–29.9). All 26 patients (27 surgeries) treated with NP medications received gabapentin, either as single therapy (65.4%) (17 patients, 18 surgeries), dual therapy with gabapentin and amitriptyline (five patients), or triple therapy with gabapentin, amitriptyline, and methadone (four patients). The mean starting (maximum) doses of gabapentin, amitriptyline, and methadone (mg/kg/day) were 20.2 (43.8), 0.5 (0.7), and 0.3 (0.3), respectively. The incidence and duration of NP, duration of treatment, and NP‐specific dose regimens were similar in the limb sparing and the amputation groups.

Conclusions

NP after definitive surgery for OS is frequently encountered, can persist for a significant time, and NP outcomes are similar in limb sparing and amputation groups.
Development and evaluation of iManage: A self‐management app co‐designed by adolescents with sickle cell disease
Authors: Crosby Lori E. , Ware Russell E. , Goldstein Alana , Walton Ashley , Joffe Naomi E. , Vogel Craig , Britto Maria T.
Published: August 2016

Background

Adolescents and young adults (AYAs) with sickle cell disease (SCD) are a vulnerable population with high risk of morbidity that could be decreased with effective self‐management. Previous research suggests that mobile applications (apps) may facilitate AYA engagement in health‐promoting behaviors. The objectives of this study were: (i) describe Internet access and use in AYA with SCD; (ii) identify barriers for self‐management in this population; (iii) collaborate with AYA to co‐design a mobile app that would minimize barriers; and (iv) evaluate the feasibility and acceptability of the app.

Procedure

In phase 1, 46 AYAs with SCD 16–24 years of age completed a survey of Internet access and use. During phase 2, 19 AYAs with SCD (average age 20 ± 2.5 years) and eight healthcare providers participated in interviews to identify barriers and co‐design sessions to develop the app. In phase 3, five AYAs with SCD completed app feasibility and usability testing.

Results

AYAs with SCD had daily Internet access (69%) using their computers (84%) or mobile phones (70%). Participants went online for health information (71%) and preferred Web sites with interactive/social features (83%). Barriers to self‐management included failing to believe that their health would suffer, lack of tailored self‐management support, lack of a mechanism to visualize self‐management progress, and limited opportunities for peer interaction around self‐management. The prototype app (iManage) was rated as highly feasible and beneficial.

Conclusions

A mobile app prototype co‐designed by AYAs with SCD may be a useful tool for engaging them in self‐management strategies designed to improve health.
Reducing ocean model imbalances in the equatorial region caused by data assimilation
Authors: Waters J. , Bell M. J. , Martin M. J. , Lea D. J.
Published: August 2016

The equatorial region is a particularly challenging area for ocean data assimilation. In this region the dominant balance near the surface is between the ocean pressure gradients and the applied wind stress. When increments are applied to an ocean model near the Equator, the pressure gradients are modified and this can cause an imbalance with the unchanged wind stress. This can lead to an initialization shock where spurious equatorial waves and vertical velocities are triggered. The equatorial waves can degrade the performance of the ocean model while the increased vertical velocities have a significant negative impact on biogeochemical models forced by these physical ocean fields. Previous studies have proposed a scheme to reduce the ocean biases associated with slowly varying errors in the applied wind stress by applying a pressure correction calculated from accumulated temperature and salinity increments. This scheme has previously been shown to reduce the mean vertical velocities and improve modelled circulation. However, when applying this scheme, we still see equatorial imbalances from data assimilation on shorter time‐scales.

We consider a new method which is an extension of the pressure correction and aims to act as a balance to the equatorial increments and reduce intialization shock. We refer to this as an incremental pressure correction. We provide a description of this method and an analysis of its energetics. In initial experiments with a global ocean data assimilation system, this new method is shown to suppress the generation of equatorial waves in a single observation experiment and to significantly reduce the standard deviation of vertical velocities in a re‐analysis experiment.
Computational approaches to the prediction of the redox potentials of iron and copper bioinorganic systems
Authors: Bruschi Maurizio , Breglia Raffaella , Arrigoni Federica , Fantucci Piercarlo , De Gioia Luca
Published: August 2016

Aim of this contribution is to review some recent quantum mechanical approaches used to compute the redox potentials of transition metal complexes, with the emphasis on copper and iron species, which are particularly relevant in inorganic biochemistry and in synthetic chemistry of bio‐mimetic compounds. The paper presents also new DFT results obtained on Cu and Fe aquo ions in the framework of the Thermodynamic Integration and Grand Canonical Ensemble approaches. Such results show that without explicit inclusion of water molecules in the external solvation shells (even using a continuum solvation model) also very advanced methodologies fail to predict the redox potential in an acceptable manner. This is a confirmation of some previous studies which however never addressed this specific problem along the aforementioned approaches. Better results are obtained, on the contrary, on a series of Cu(II) complexes with Gly, Ala, en, Im, and water ligands with coordination type
or N4. In this case, the complexes are surrounded by nine water molecules which may partially alleviate the inadequacy of the continuum solvent models, especially in the case of highly positively charged species.
Towards a secure hybrid adaptive gateway discovery mechanism for intelligent transportation systems
Authors: Boukerche Azzedine , Aljeri Noura , Abrougui Kaouther , Wang Yan
Published: August 2016

In the recent years, we are witnessing a growing interest into the design of smart vehicles and smart roads for Intelligent transportation systems. Vehicles as part of the Internet of Things should provide to the driver and passenger with a variety of services using efficient gateway discovery mechanism while maintaining a certain level of security and authentication to avoid potential malicious attacks. In this paper, we propose a secure hybrid adaptive gateway discovery and communication protocol for smart vehicular networks, which we refer to as SEGAL. Our proposed SEGAL protocol is based upon building a secure clustered vehicular network, and permits the exchange of gateway discovery messages through authenticated clusterheads and cluster members. We shall present the design of our protocol, and describe how it can overcome the possible malicious attacks that might harm the network. Then, we report its efficiency and scalability using an extensive set of simulation experiments using Ns‐2 simulator. Our results indicate that the proposed SEGAL protocol is scalable while achieving high success rate, low response time and dropping rate. Copyright © 2016 John Wiley & Sons, Ltd.
Theoretical and Experimental Study of the Antioxidant Behaviors of 5‐O‐Caffeoylquinic, Quinic and Caffeic Acids Based on Electronic and Structural Properties
Authors: Uranga Jorge G. , Podio Natalia S. , Wunderlin Daniel A. , Santiago Ana N.
Published: August 2016

The aim of this study was to elucidate the structural and electronic factors that determine the antioxidant capacity of 5‐O‐caffeoylquinic, caffeic and quinic acids under different experimental conditions. Antioxidant capacity was measured using different in vitro assays, involving diverse mechanisms of antioxidant action, namely, radical scavenging or reduction. The mechanisms of these reactions were analyzed by a theoretical study using the Density Functional Theory. Results allow relating in vitro antioxidant capacity of these three compounds with their chemical structures. The antioxidant capacity experimentally observed for these three acids was interpreted considering the reaction mechanism involved, the nature and stability of the intermediate formed, the formation and reaction of secondary compounds, and the effect of the reaction medium. The main goal of this report is presenting a theoretical analysis of reactions implicated in the antioxidant capacity, identifying the causes that increase or decrease such property. Thus, we present a quantum mechanical description of the antioxidant properties involved with these three compounds, considering equilibria and secondary oxidations involved.
Influence of Halogen Atoms on Spin‐Crossover Properties of 1,2,4‐Triazole‐Based 1D Iron(II) Polymers
Authors: Luo Yang‐Hui , Sun Yu , Liu Qing‐ling , Yang Li‐Jing , Wen Gao‐Ju , Wang Ming‐Xin , Sun Bai‐Wang
Published: August 2016

The introduce of halogen atoms (F, Cl, Br, I) to the triazole‐based ligand N‐benzyl‐4‐amino‐1, 2, 4‐triazole (L) have shown a significant effect on the spin‐crossover (SCO) properties of the corresponding one‐dimensional (1D) coordination Fe (II) polymers with chemical formula [Fe(4‐X–L)3](BF4)2 (X=F, Cl, Br, and I). Compared with the [FeL3](BF4)2, the electronegative halogen atoms have increased the π‐acceptor character of these ligands, which thus improved the ligand field strength and induced the occurrence of SCO for the Fe (II) polymers at higher temperatures. The SCO transition temperatures T1/2 have changed from 200 K to 249 (I), 250 (Br), 252 (Cl) and 275 (F) K, respectively. More importantly, the UV‐Vis absorption spectrum and density functional theory (DFT) calculations indicated that the transition temperatures and the width of thermal hysteresis loops have shown a positive correlation with the electronegativity of the halogen atoms.
Functionalized Multi‐Walled Carbon Nanotubes (f‐MWCNT) as Highly Efficient and Reusable Heterogeneous Catalysts for the Synthesis of Acridinedione Derivatives
Authors: Ulus Ramazan , Yıldız Yunus , Eriş Sinan , Aday Burak , Şen Fatih , Kaya Muharrem
Published: August 2016

Addressed herein, carboxylic acid groups were immobilized onto carbon nanotubes and their catalytic properties were examined for the first time for the synthesis of acridinedione derivatives, opening new paths in the investigation of catalysis and their comparison with carbon‐based materials. An efficient methodology for the synthesis of acridinedione derivatives has been achieved by one‐pot, multi‐component condensation of dimedone, substitute aromatic aldehydes, various aromatic amines and, in the presence of the easily available, inexpensive, and nontoxic f‐MWCNTs as versatile biodegradable catalysts. At this method, f‐MWCNTs carrying simple carboxylic acid functionalities catalyze the model reaction in ethanol providing the product in a quantitative yield. This highly monodisperse catalyst is one of the most efficient catalysts which gives the highest yield of products in the shortest time. Its high‐yield efficiency, clean, eco‐friendly, simple work‐up procedure, and easy purification are regarded to be the main advantages of this method. The synthesized compounds are characterized using spectroscopic (IR, 1H‐NMR, 13C‐NMR and HRMS) techniques.
The Quantitative Evaluations of the Luminescent Sensing Ability to Cu2+ Based on Two Homologous Crystalline Coordination Polymers
Authors: Pang Ling‐Yan , Bai Nan‐Nan , Jin Jun‐Cheng , Yang Guo‐Ping , Wu Yun‐Long , Luan Xin‐Jun , Wang Yao‐Yu
Published: August 2016

A systematic study has been well conducted on two new homologous Cd(II)‐based luminescent coordination polymers (LCPs), [Cd3(Httac)2(H2O)8]⋅(H2O)2 (1) and [Cd2(ttac)(H2O)6]⋅(H2O)6 (2), (H4ttac=1,1′,2′,1′′‐terphenyl‐4,4′,4′′,5′‐tetracarboxylic acid), to explore their sensing mechanisms to Cu2+. Both 1 and 2 are able to respond to Cu(NO3)2 through luminescent quenching but with the distinct quenching modes. The Stern‐Volmer curves of 1 and 2 both deviate from the linearity, indicating the coexistence of the dynamic and static quenching. Concentration‐dependent lifetime experiments have been carried out carefully to confirm the dynamic quenching and to calculate the dynamic constants quenching Kc; the static quenching is supported by time‐dependent intensity measurements where the intensities of 1 decrease along with time, while for 2, it's a constant in time; the corresponding constants Ks have also been obtained, thus achieving the quantitative evaluations of quenching processes. More importantly, the relationships between the sensing efficiency and inherent structures of two LCPs have been discussed, and the promotion suggestions have also been given finally.
Assessment of Antimicrobial Activity, Reactivity and Non‐Linear Optical Properties of New Pyrazoline Derivatives having Pyrrole moiety
Authors: Rawat Poonam , Singh R. N. , Sahu Sangeeta , Niranjan Priydarshni , Rani Himanshu , Saxena Rajat , Ahmad Sartaj
Published: August 2016

The purpose of this work is to study antimicrobial activity, chemical reactivity and non‐linear optical properties of newly synthesized and characterized 2‐pyrazoline derivatives having pyrrole moiety (4a–d). 1,3,5‐trisubstituted pyrazoline derivatives (4a–c) and 3, 5‐di‐aryl N‐substituted carbonyl pyrazoline derivative (4 d) were synthesized by simple and efficient approach using cyclization reaction of chalcones (3a–c) and aromatic hydrazine (AH) / aromatic acid hydrazide (AAH) in the presence of acid catalyst. The conformational investigation has been performed with the help of potential energy surface scan to understand and find out the stable conformers. All synthesized compounds have been characterized by spectroscopic (1H and13C NMR, UV–Visible, FT–IR) techniques. Using self‐consistent reaction field (SCRF) method, the solvent‐induced effects on dipole moment (μ0), mean polarizability (|α0|), anisotropy of polarizability (Δα) and the first hyperpolarizability were studied for all compounds and found that theβ0values increase monotonically as the polarity increases. Theβ0values of compounds are higher than the standardp‐nitroaniline (p‐NA) in solvent as well as in gas phase. The screening of the synthesized compounds for antimicrobial activity was performed againstS. aureus, E. coli, C. AlbicansandA. niger. The assayed compounds showed a good antibacterial (against gram positive and negative bacteria) and antifungal activity.
Efficient Production of Hydrogen from Decomposition of Formic Acid over Zeolite Incorporated Gold Nanoparticles
Authors: Gallas‐Hulin Agata , Mielby Jerrik , Kegnæs Søren
Published: August 2016

Formic acid has a great potential as a safe and convenient source of hydrogen for sustainable chemical synthesis and renewable energy storage. Here, we report a heterogeneous gold nanoparticles catalyst for efficient production of hydrogen from vapor phase decomposition of formic acid using zeolite incorporated gold nanoparticles. The catalyst is prepared by pressure assisted impregnation and reduction (PAIR), which results in a uniform distribution of small gold nanoparticles that are incorporated into zeolite silicalite‐1 crystals. Consequently, the incorporated nanoparticles exhibit increased sintering stability. Based on these results, we believe that incorporation of metal nanoparticles in zeolites may find use as highly active and selective heterogeneous catalysts for the production of hydrogen in future renewable energy applications.
Direct Enzymatic Synthesis of 1‐Phosphatidyl‐β‐D‐glucose by Engineered Phospholipase D
Authors: Inoue Arisa , Adachi Masaatsu , Damnjanović Jasmina , Nakano Hideo , Iwasaki Yugo
Published: August 2016

A simple, direct method for the synthesis of 1‐phosphatidyl‐β‐D‐glucose (1‐PGlc) was established, being the first example of direct enzymatic synthesis of this recently discovered, highly important bioactive phospholipid. The method employs phospholipase D (PLD, E.C. 3.1.4.4)‐catalyzed transphosphatidylation, in which the polar head group of phosphatidylcholine is exchanged to glucose. Although wild‐type PLD can catalyze the transfer reaction, it provides only 6‐phosphatidyl‐glucose, a positional isomer of 1‐PGlc, due to its strong preference towards the primary hydroxyl group. To synthesize 1‐PGlc, engineered PLD variants, previously isolated as the ones active on secondary hydroxyls of inositol, were screened for the ability to catalyze the reaction. One of the variants, 187K/191W/385Y (KWY), was identified as the best‐performing in 1‐PGlc synthesis, however, in addition to 1‐PGlc the reaction with KWY also afforded undesired positional isomers as byproducts. To facilitate the isolation of 1‐PGlc, the isomers were converted into the corresponding amines by reductive amination. Following the column chromatography, the desired product was isolated with the overall yield of 12.5 %. The structure of the product was confirmed by 1H‐NMR analysis.
A Novel Protocol for the Cu‐Catalyzed Sonogashira Coupling Reaction between Aryl Halides and Terminal Alkynes using trans‐1,2‐Diaminocyclohexane Ligand
Authors: Asha Sujatha , Thomas Anns Maria , Ujwaldev Sankuviruthiyil M. , Anilkumar Gopinathan
Published: August 2016

An efficient Sonogashira coupling reaction has been reported using cost effective and easily accessible CuI/trans‐1,2‐diaminocyclohexane catalytic system. The newly developed method can be successfully employed for the coupling between aryl and heteroaryl halides with terminal acetylenes. Furthermore this methodology can be extended for the one pot synthesis of biologically active benzofuran derivatives.
Iron‐Mediated Direct Ortho‐ Nitration of Anilides and Aromatic Sulfonamides under Aerobic Oxidation Conditions.
Authors: Botla Vinayak , Ramana Daggupati V. , Chiranjeevi Barreddi , Chandrasekharam Malapaka
Published: August 2016

Direct ortho‐nitration of anilides and aromatic sulfonamides employing inexpensive, nontoxic and readily available iron reagent is described. It is proposed that the aromatic nitration reaction operates through a single electron transfer (SET) mechanism and is effective in the absence of additive. The reaction produced a variety of mono nitrated derivatives with moderate to excellent yields. The reaction provides a practical method for the synthesis of nitro compounds owing to its simple experimental procedure, mild reaction conditions, broad substrate scope and the functional group compatibility.
Syntheses of Hierarchical MnO2via H2O2 Selectively Reducing KMnO4 for Catalytic Combustion of Toluene
Authors: Chen Jin , Chen Xi , Xu Zhen , Xu Wen‐Jian , Li Juan‐Juan , Jia Hong‐Peng , Chen Jing
Published: August 2016

MnO2 materials were facilely prepared via the rapid redox reactions of KMnO4 and H2O2 in acidic medium, which exhibit the significant improvement of catalytic activity in the degradation of gaseous toluene compared to commercial MnO2. It was found that the molar ratio of H2O2/KMnO4 has a great influence on the crystalline phase, morphology and average oxidation state of the as‐prepared MnO2. The 3‐MnO2 sample prepared by using three equivalents of stoichiometric H2O2 displays the best catalytic activity for the total combustion of toluene (concentration is up to 1000 ppm) at 300 oC. The mechanism of the influence of different H2O2 addition amount has also been discussed by catalytic performance and nature of materials.
Pine Wood Extracted Activated Carbon through Self‐Activation Process for High‐Performance Lithium‐Ion Battery
Authors: Xia Changlei , Kang Chiwon , Patel Mumukshu D. , Cai Liping , Gwalani Bharat , Banerjee Rajarshi , Shi Sheldon Q. , Choi Wonbong
Published: August 2016

Self‐activation is an ecological friendly and inexpensive process for the fabrication of large scale activated carbon (AC), which precludes the use of activating agents and takes advantage of the emitted gases from the simple pyrolysis of pine wood to stimulate the converted carbon. The tailoring of process parameters such as dwelling time assists in optimizing the pore size distribution comprised of meso‐ and micropores, offering favorable physical properties including specific surface area of 2738 m2 g−1 and specific pore volume of 2.209 cm3 g−1 for superior electrochemical performance of Li‐ion batteries. The AC‐based anode shows a high cycling stability with a reversible specific capacity of 384 mAh g−1 at 1C after 200 cycles, which is close to the theoretical specific capacity of graphite. The finding suggests that the self‐activation process, a green, scalable, and efficient process, has great potential to be developed into next‐generation high‐performance electrode materials for electrochemical energy storage devices.
Dual Behaviour of Amorphous Carbon Released Electrochemically from Graphite
Authors: Oliveira Maria C. , Viana Ana S. , Botelho do Rego Ana M. , Ferraria Ana M. , Tavares Pedro B. , Veloso Andreia D. , Videira Romeu A.
Published: August 2016

Here we show that the main product released from graphite in the early stages of the anodic polarization is a carbon‐based salt comprised of an amorphous carbonaceous material with delocalized negative charge, counterbalanced by sodium cations. Remarkably, this material shows a dual behaviour: it behaves as an electrolyte in aqueous medium, which has the ability to enhance the capacitive properties of the electrode‐solution interface and in the solid state it can be used as an electrode material with meaningful capacitive properties.
Extremely Small Iron Oxide Nanoparticles Stabilized with Catechol‐Functionalized Multidentate Block Copolymer for Enhanced MRI
Authors: Li Puzhen , Xiao Wangchuan , Chevallier Pascale , Biswas Depannita , Ottenwaelder Xavier , Fortin Marc‐André , Oh Jung Kwon
Published: August 2016

An effective mussel‐inspired multidentate block copolymer strategy having pendant anchoring catechol groups (Cat‐MDBC) to stabilize extremely small iron oxide nanoparticles (ESNPs) in water is reported. The resultant aqueous Cat‐MDBC/ESNP colloids with diameter ≈16 nm and core diameter ≈2 nm were non‐toxic to cells up to 200 μg/mL and exhibit excellent colloidal stability in physiological condition (pH=7) as well as in the presence of IgG model protein. More promisingly, they had the relaxivity ratio to be r2/r1=1.5, which is significantly lower than PEG‐coated SNPs with core diameter=1.5‐6 nm; further which is similar to those of Gd‐DOTA T1‐weighted contrast agents. These results suggest that aqueous Cat‐MDBC/ESNP colloids could be a promising candidate for T1‐weighted MRI contrast enhancement.
Versatile, Fast, and Easy One‐Step Method for the Synthesis of Hydrophilic Lanthanide‐Doped Nanoparticles
Authors: Graña‐Suárez Laura , Verboom Willem , Sarkar Shyam , Mahalingam Venkataramanan , Huskens Jurriaan
Published: August 2016

The preparation of hydrophilic lanthanide‐doped nanoparticles (NPs) following a versatile one‐step colloidal method at low temperature and short reaction time with different doped lanthanides, capping ligands, and fluoride sources is presented. The photoluminescence of the particles, via both downshifting (DS) and up‐conversion (UC), was easily tuned from blue or green by simply changing the lanthanides used. When using the same core type of particles, the size and the photoluminescence intensity were tuned by changing the fluoride source or the capping ligand used: the size of the DSNPs varied from 9 nm (PAA) to 24 nm (PEI) when changing the capping ligand, while if PAA was used as capping ligand, the nanoparticles presented the most intense emission bands. Supramolecular host groups were introduced on the surface of the UCNPs by grafting cyclodextrin (CD) groups onto the capping ligand PiBMA prior to particle synthesis, reaching a CD surface density of 0.28 CD nm‐2. In this case, a small particle size (11.7 nm) and strong UC emission bands were observed.
Phase‐Transfer Catalysis with Ionene Polymers
Authors: Tiffner Maximilian , Zielke Katharina , Mayr Judith , Häring Marleen , Díaz Díaz David , Waser Mario
Published: August 2016

Ionene polymers were found to be versatile phase‐transfer catalysts for a variety of different reactions like α‐alkylation reactions or Michael addition reactions. Reasonably low catalyst loadings allowed us to obtain the target products under operationally simple biphasic conditions at ambient temperature and the ionenes can be recovered and reused by simple filtration.
Size‐Tunable Olive‐Like Anatase TiO2 Coated with Carbon as Superior Anode for Sodium‐Ion Batteries
Authors: Chen Jun , Zhang Yan , Zou Guoqiang , Huang Zhaodong , Li Simin , Liao Hanxiao , Wang Jufeng , Hou Hongshuai , Ji Xiaobo
Published: August 2016

Olive‐shaped anatase TiO2 with tunable sizes in nanoscale are designed employing polyvinyl alcohol (PVA) as structure directing agents to exert dramatic impacts on structure shaping and size manipulation. Notably, the introduced PVA simultaneously serves as carbon sources, bringing about a homogenous carbon layer with intimate coupling interfaces for boosted electronic conductivity. Constructed from tiny crystalline grains, the uniformly dispersed carbon‐coated TiO2 nano‐olives (TOC) possess subtle loose structure internally for prompt Na+ transportations. When utilized for sodium‐ion storage, the size effects are increasingly significant at high charge–discharge rates, leading to the much superior rate performances of TOC with the smallest size. Bestowed by the improved Na+ adsorption and diffusion kinetics together with the promoted electron transfer, it delivers a high specific capacity of 267 mAh g−1 at 0.1 C (33.6 mA g−1) and sustains 110 mAh g−1 at a rather high rate of 20 C. Even after cycled at 10 C over 1000 cycles, a considerable capacity of 125 mAh g−1 with a retention of 94.6% is still obtained, highlighting its marvelous long‐term cyclability and high‐rate capabilities.
A Catalyst for Change: Service‐Learning for TESOL Graduate Students
Authors: Cho Hyesun , Gulley Jeremy
Published: August 2016

This study explores ways in which TESOL graduate students were engaged in service‐learning at a public university in the midwestern United States. It describes the experiences of both domestic and international students with service‐learning that was incorporated into a hybrid graduate‐level TESOL course. Data were collected throughout the semester through weekly discussions on Blackboard, three reflective journals in which students wrote about their experiences on‐site, and in‐person discussions in the classroom, as well as through a focus group interview at the end of the semester. Findings reveal how service‐learning contributed to developing students’ intercultural awareness, civic responsibility, and teacher identity. Students also appreciated the opportunity to share their experience with the class and receive support from their peers. Overall, service‐learning gave students hands‐on experience that allowed them to translate theory into practice, thus making their learning authentic, creative, and meaningful. The findings raise important questions for TESOL educators and researchers to address as we reimagine and reconceptualize the curriculum for promoting diversity and social justice. The article concludes with suggestions for implementing service‐learning in a TESOL program.
Building the drains: the lymphatic vasculature in health and disease
Authors: Venero Galanternik Marina , Stratman Amber N. , Jung Hyun Min , Butler Matthew G. , Weinstein Brant M.
Published: August 2016

The lymphatic vasculature is comprised of a network of endothelial vessels found in close proximity to but separated from the blood vasculature. An essential tissue component of all vertebrates, lymphatics are responsible for the maintenance of fluid homeostasis, dissemination of immune cells, and lipid reabsorption under healthy conditions. When lymphatic vessels are impaired due to invasive surgery, genetic disorders, or parasitic infections, severe fluid build‐up accumulates in the affected tissues causing a condition known as lymphedema. Malignant tumors can also directly activate lymphangiogenesis and use these vessels to promote the spread of metastatic cells. Although their first description goes back to the times of Hippocrates, with subsequent anatomical characterization at the beginning of the 20th‐century, the lack of identifying molecular markers and tools to visualize these translucent vessels meant that investigation of lymphatic vessels fell well behind research of blood vessels. However, after years under the shadow of the blood vasculature, recent advances in imaging technologies and new genetic and molecular tools have accelerated the pace of research on lymphatic vessel development. These new tools have facilitated both work in classical mammalian models and the emergence of new powerful vertebrate models like zebrafish, quickly driving the field of lymphatic development back into the spotlight. In this review, we summarize the highlights of recent research on the development and function of the lymphatic vascular network in health and disease. WIREs Dev Biol 2016, 5:689–710. doi: 10.1002/wdev.246

This article is categorized under:

Gene Expression and Transcriptional Hierarchies > Cellular Differentiation

Signaling Pathways > Cell Fate Signaling

Vertebrate Organogenesis > Musculoskeletal and Vascular
Four Gadolinium Coordination Compounds Derived from Various Tetrazole‐Containing Carboxylic Acids
Authors: Shen Lei , Min Yu‐Ting , Bai Xue , Wang Jing , Wu Qi , Yang Jie , Chen Hong‐Jian , Geng Fei , Yang Gao‐Wen , Li Qiao‐Yun
Published: August 2016

Reactions of four different tetrazole‐containing carboxylic acids with GdCl3·6H2O, produced the coordination compounds, [Gd4(pytza)5(H2O)10(μ‐O) Cl]·4H2O·2Cl (1) [pytza = 2‐(5‐(pyridine‐4‐yl)‐2H‐tetrazole‐2‐yl)acetato], [Gd(pztza)2(H2O)6]·pztza·3H2O (2), [pztza = 2‐(5‐(pyrazin‐2‐yl)‐2H‐tetrazol‐2‐yl) acetato], [Gd(pmtza)2(H2O)6]Cl·2H2O (3), [pmtza = 2‐(5‐(pyrimidyl‐2‐yl)‐2H‐tetrazol‐2‐yl) acetato], and Gd(tzpya)2(H2O)5]Cl·4H2O (4) [tzpya = 2‐(4‐(5H‐tetrazol‐5‐yl)pyridin‐1(4H)‐yl) acetato]. The compounds were structurally characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction. X‐ray diffraction analysis reveals that compound 1 displays a 2D single layered network and compounds 2–4 are mononuclear. Compounds 1–4 are self‐assembled to form 3D networks by hydrogen bonding interactions. Furthermore, the luminescent properties in the solid state at room temperature were investigated.
For Economic Advantage or Something Else? A Case for Racial Identification Switching
Authors: Contreras Salvador
Published: August 2016

The identity choices people take on serve as a filter for viewing the world. It is believed that race identity formation is in part a response to economic and social incentives. Using NELS 1988 dataset we evaluate at the individual level factors that affect changes in self-reported racial identity. We find that being multiracial, living in a non-affirmative action ban state, and relative income/education measures within race groups have an effect on racial identity switching. We find strong evidence that the social-political environments surrounding an affirmative action ban alters the likelihood that an individual will change race. Our results suggest that social factors when present dominate economic incentives to take on a different racial identity.
Réévaluation du sexe et de l'âge au décès du sujet azilien Le Peyrat 5, Saint-Rabier (Dordogne, France)
Authors: Samsel M. , Knüsel C.J. , Villotte S.
Published: August 2016

Cette note propose une réévaluation de la diagnose sexuelle et de la détermination de l'âge au décès de l'individu azilien Le Peyrat 5 (LP5) [Dordogne, France] daté directement à 11430 ± 150 BP (GifA-99117 ; 13566–13017 cal. BP) à partir de méthodes fiables appliquées à l'os coxal. Cette étude confirme que le squelette LP5 est celui d'un homme adulte vraisemblablement décédé entre 30 et 49 ans. La détermination fiable du sexe de vestiges du Paléolithique supérieur est notamment importante pour la construction d'un corpus de référence visant à mieux appréhender le dimorphisme sexuel extra-pelvien des individus de cette période.
Effect of combined spinal–epidural analgesia in labor on frequency of emergency cesarean delivery among nulliparous Chinese women
Authors: Wang Fen , Cao Yun‐xia , Ke Shan‐gao , Zhu Tao‐hua , Zhang Miao
Published: August 2016

Objective

To determine whether combined spinal–epidural analgesia (CSEA) during labor increases the frequency of emergency cesarean delivery among Chinese nulliparous women.

Methods

In a retrospective study, the medical records of nulliparous women with a singleton fetus in cephalic presentation who delivered at term at Tongling Maternity Hospital, China, between January 2012 and December 2014 were reviewed. Information about CSEA, mode of delivery, labor duration, oxytocin augmentation, and neonatal outcome was obtained. Logistic regression was used to examine independent associations between CSEA and emergency cesarean after controlling for confounding variables.

Results

Among 3456 women included, 1786 (51.7%) received CSEA and 1670 (48.3%) received no labor analgesia. Emergency cesarean was more frequent among CSEA users (219/1786 [12.3%]) than non‐users (119/1670 [7.1%]; P < 0.001). Among the maternal–fetal variables included in multivariate regression, maternal age, maternal height, cervical dilatation at admission, birth weight, and CSEA use were significantly associated with emergency cesarean. After adjustment, women with CSEA maintained a slightly increased risk for cesarean (adjusted odds ratio 1.54, 95% confidence interval 1.20–2.00).

Conclusion

Among Chinese nulliparous women, use of CSEA for labor pain was associated with an increased risk of emergency cesarean delivery; moreover, this effect was maintained after adjustment for other potential obstetric risk factors.