bluuebunny/crossref_metadata_2025 huggingface dataset:
Direct and indirect approaches to identify drug modes of action
Authors: Tulloch Lindsay B. , Menzies Stefanie K. , Coron Ross P. , Roberts Matthew D. , Florence Gordon J. , Smith Terry K.
Published: December 2017

Phenotypic assays are becoming increasingly more common among drug discovery practices, expanding drug target diversity as lead compounds identified through such screens are not limited to known targets. While increasing diversity is beneficial to the drug discovery process and the fight against disease, the unknown modes of action of new lead compounds can hamper drug discovery as, in most cases, the process of lead compound optimization is made difficult due to the unknown nature of the target; blindly changing substituents can prove fruitless due to the inexhaustible number of potential combinations, and it is therefore desirable to rapidly identify the targets of lead compounds developed through phenotypic screening. In addition, leads identified through target‐based screening often have off‐target effects that contribute towards drug toxicity, and by identifying those secondary targets, the drugs can be improved. However, the identification of a leads mode of action is far from trivial and now represents a major bottleneck in the drug discovery pipeline. This review looks at some of the recent developments in the identification of drug modes of action, focusing on phenotype‐based methods using metabolomics, proteomics, transcriptomics, and genomics to detect changes in phenotype in response to the presence of the drug, and affinity‐based methods using modified/unmodified drug as bait to capture and identify targets. © 2017 IUBMB Life, 70(1):9–22, 2018
From Situated Privilege to Dis/abilities: Developing Critical Literacies Across Social Issues
Authors: Young Sara Lewis‐Bernstein
Published: December 2017

The purpose of this study was to investigate how curriculum grounded in critical literacy strategies supports critical language awareness and activism across social issues and identities. The research is grounded in theories of critical literacies, discursive practices, and situated privilege. Critical practitioner research was used to collect classroom data, which were then coded and analyzed through critical discourse analysis to examine language, literacy, and examples of activism in the data set. Findings indicate that although strategies such as decoding discourses and ideologies, revealing connections between language and power, and engaging in social action are important to developing critical literacies across social issues, understanding privilege, power, and one's own role in maintaining oppression are also crucial to developing critical literacies around issues of situated privilege. Implications for teachers include consideration for the complexity of identities and social locations in critical literacy pedagogies.
Unlocking the Cage: Empowering Literacy Representations in Netflix'sLuke CageSeries
Authors: Toliver S.R.
Published: December 2017

Popular culture aids in the conditioning of U.S. society, assisting in the determination of who is esteemed as literate and who is disgraced with illiteracy. Unfortunately, pop culture depictions of black male literacy often reify the stereotype that black males are less literate than their peers. Although a real issue presents itself in the opportunity gap that exists between black males and other racial groups, however, focusing on the negative fails to complicate the narrative. The purpose of this article is to confound monolithic representations by acknowledging positive, nuanced, and complex black male literacy practices. The author uses critical rhetorical analysis and positioning theory to highlight Netflix'sLuke Cageseries as a site where empowering literacy practices prevail. For educators, the author suggests using a critical rhetorical analysis of popular culture to examine and question content that presents static representations of black male literacy.
Comparison of sonography and MRI in the evaluation of stability of capitellar osteochondritis dissecans
Authors: Yoshizuka Masaaki , Sunagawa Toru , Nakashima Yuko , Shinomiya Rikuo , Masuda Tetsuo , Makitsubo Manami , Adachi Nobuo
Published: December 2017

Purpose

To compare the diagnostic accuracies of ultrasonography (US) and magnetic resonance imaging (MRI) with intraoperative capitellar osteochondritis dissecans (COCD) fragment stability findings.

Methods

Patients whose International Cartilage Repair Society (ICRS) osteochondritis dissecans (OCD) classifications were I/II (stable) or III (unstable) were included. Patients underwent preoperative US and MRI. On US, lesions were evaluated as unstable when irregular contours of the chondral surface were observed. On MRI, lesions were evaluated as unstable when articular bone irregularity, a T2 high signal intensity interface, or a high signal intensity line through the articular cartilage was observed. Using the surgical assessment as the gold standard, accuracies of fragment stability diagnoses were calculated for US and MRI.

Results

Thirty‐four patients with OCD classifications of I/II (stable) or III (unstable) were included. Twenty‐four patients (stable: 12, unstable: 12) underwent preoperative US; 22 (stable: 11, unstable: 11) underwent preoperative MRI. Preoperative US and MRI stability assessments correctly matched intraoperative fragment findings in 23 of 24 patients and 16 of 22 patients, respectively. US criteria in this study achieved superior accuracy compared with MRI criteria (96% vs. 73%; P < .05).

Conclusion

US was a useful tool for evaluating fragment instability in COCD.
The effect of an urban park on the microclimate in its vicinity: a case study for Antwerp, Belgium
Authors: Toparlar Y. , Blocken B. , Maiheu B. , van Heijst G. J. F.
Published: December 2017

An urban park can exhibit a cooling effect not only in the park itself, but also in its wake with respect to the prevailing wind. This study investigates the cooling potential of an urban park in Antwerp, Belgium focusing on two parameters: (1) intensity of the cooling effect, indicating the maximum reduction in air temperature and (2) range of the cooling effect, indicating the maximum horizontal distance where a minimum of 0.1 °C cooling effect is present. Computational fluid dynamics (CFD) simulations are performed using the three‐dimensional unsteady Reynolds‐averaged Navier–Stokes equations. Coupled simulations of wind flow and heat transfer consider all the conductive, convective and radiative heat transfer processes but not the long‐wave radiation heat exchange between buildings, trees and ground. The vegetation model used in this study is evaluated with experimental data from an earlier study. Moreover, the simulated air temperatures inside the Antwerp city center are compared with available measurement data. Following the fairly‐good predictions from CFD simulations, results from the following cases are compared: (1) base case with the park, (2) a case with an open square instead of the park, and (3) a case with representative buildings instead of the park. The results indicate a maximum daytime intensity and range of the cooling effect of 3.4 °C and 498 m at 1500 LST (UTC + 2, Central European Summer Time). Further analysis shows that the cooling effect is more profound closer to the ground. Apart from the daytime cooling effect, the park investigated has the potential to lower wind velocities, resulting in increased air temperatures during the night‐time (at 0000 LST) by 0.9 °C, although this number might be slightly different given the neglect of long‐wave radiation heat exchange between buildings, trees and ground.
Simultaneous determination of polysaccharides and 21 nucleosides and amino acids in different tissues of Salvia miltiorrhiza from different areas by UV–visible spectrophotometry and UHPLC with triple quadrupole MS/MS
Authors: Xiang Xiang , Sha Xiuxiu , Su Shulan , Zhu Zhenhua , Guo Sheng , Yan Hui , Qian Dawei , Duan Jin‐ao
Published: December 2017

Salvia miltiorrhiza, a traditional Chinese medicine, is a widely used herbal medicine to treat cardiovascular and cerebrovascular diseases. In this study, ultraviolet (UV)–visible spectrophotometry and ultra‐high performance liquid chromatography with triple quadrupole tandem mass spectrometry analytical methods were used for rapid quantification of polysaccharides and 21 nucleosides and amino acids in S. miltiorrhiza to determine 17 samples of different tissues from different areas. Based on the total contents, hierarchical clustering analysis and principal components analysis were performed to classify these samples. The established methods were validated with good linearity, precision, repeatability, stability, and recovery. Chemical analysis revealed a higher content of total analytes in the sample of inflorescence from Nanjing (34.17 mg/g), sample of root and rhizome from Shaanxi (34.13 mg/g) and sample of stem and leaf from Nanjing (31.14 mg/g), respectively, indicating that root and rhizome from Shaanxi and the aerial parts from Nanjing exhibited the highest quality due to their highest content. In addition, contents of nucleosides and amino acids in the aerial parts (14.67 mg/g) were much higher than that in roots and rhizomes (9.17 mg/g). This study suggested that UV–visible spectrophotometry and ultra‐high performance liquid chromatography with triple quadrupole tandem mass spectrometry are effective techniques to analyze polysaccharides, nucleosides, and amino acids in plants, and they provided valuable information for the development and utilization value of the aerial parts of S. miltiorrhiza. This analysis would also provide useful information for the quality control of S. miltiorrhiza.
Chiral separation of lenalidomide by liquid chromatography on polysaccharide‐type stationary phases and by capillary electrophoresis using cyclodextrin selectors
Authors: Szabó Zoltán‐István , Foroughbakhshfasaei Mohammadhassan , Gál Réka , Horváth Péter , Komjáti Balázs , Noszál Béla , Tóth Gergő
Published: December 2017

Complementary techniques were applied for the investigation of the chiral recognition and enantiomeric resolution of lenalidomide using various cyclodextrins and polysaccharides as chiral selectors. The high‐performance liquid chromatography enantioseparation of the anticancer drug was achieved using polysaccharide‐type chiral stationary phases in polar organic mode. Elution order and absolute configuration were elucidated by combined circular dichroism spectroscopy and time‐dependent density functional theory calculations after the isolation of pure enantiomers. Chiral selector dependent and mobile‐phase dependent reversal of the enantiomer elution order was observed, and the nonracemic nature of the lenalidomide sample was also demonstrated. Eight anionic cyclodextrins were screened for their ability to discriminate between the uncharged enantiomers by using capillary electrophoresis. Only two derivatives presented chiral interactions, these cases being interpreted in terms of apparent stability constants and complex mobilities. The best results were delivered by sulfobutylether‐β‐cyclodextrin, where quasi‐equal stability constants were recorded and the enantiodiscrimination process was mainly driven by different mobilities of the transient diastereomeric complexes. The optimized high‐performance liquid chromatography (Chiralcel OJ column, pure ethanol with 0.6 mL/min flow rate, 40°C) and capillary electrophoresis methods (30 mM sulfobutylether‐β‐cyclodextrin, 30 mM phosphate pH 6.5, 12 kV applied voltage, 10°C) were validated for the determination of 0.1% (R)‐lenalidomide as a chiral impurity, which could be important if a racemic switch is achieved.
Hydrologic setting constrains lake heterotrophy and terrestrial carbon fate
Authors: Jones Stuart E. , Zwart Jacob A. , Kelly Patrick T. , Solomon Christopher T.
Published: December 2017

Current efforts to scale lake processes rely heavily on empirical observations and do not consider inter‐lake heterogeneity that is likely to regulate terrestrial dissolved organic carbon (tDOC) decomposition in lakes. We created a simple, analytical model of tDOC decomposition in lakes that highlights the role of lake size and catchment hydrologic export. Our model predicts a hydrologically mediated tradeoff between the instantaneous rate of tDOC decomposition and the fraction of the tDOC load that is decomposed within a lake. We also predict that variation in the importance of evaporation as a hydrologic export generates meaningful variation in tDOC decomposition at a given hydrologic residence time. These patterns of tDOC decomposition that emerge from lakes' hydrologic settings suggest that past attempts to scale lake carbon biogeochemistry may be biased. Our model provides context for empirical studies of lake carbon cycling and enables informed scaling of lake carbon biogeochemistry.
Ultrahigh Flux Composite Hollow Fiber Membrane via Highly Crosslinked PDMS for Recovery of Hydrocarbons: Propane and Propene
Authors: Liang Can Zeng , Chung Tai‐Shung
Published: December 2017

In order to make membrane separation technologies more cost‐competitive with the well‐established processes that are energy intensive for gas/vapor separation, a defect‐free membrane with a high gas permeance is necessary. However, it remains challenging to meet these needs because of the difficulties in developing a suitable material and process that are economical and practical. Herein, a novel and straightforward strategy is presented to produce a defect‐free hollow fiber composite membrane using a highly crosslinked polydimethylsiloxane (PDMS) synthesized by using a postcrosslinking method. The PDMS can be directly coated on a polyacrylonitrile (PAN) membrane substrate, and the resultant PDMS/PAN composite membrane has ultrahigh C3H8 and C3H6 permeances that are higher than 10 000 and 11 000 GPU, respectively, and the corresponding permselectivity of C3H8/N2 and C3H6/N2 are about 21 and 24, respectively. The newly developed methods and materials may open up a new cost‐effective method to fabricate next‐generation composite membranes for the recovery of hydrocarbons, organic vapors, and gases.
Supramolecular “Step Polymerization” of Preassembled Micelles: A Study of “Polymerization” Kinetics
Authors: Yang Chaoying , Ma Xiaodong , Lin Jiaping , Wang Liquan , Lu Yingqing , Zhang Liangshun , Cai Chunhua , Gao Liang
Published: December 2017

In nature, sophisticated functional materials are created through hierarchical self‐assembly of nanoscale motifs, which has inspired the fabrication of man‐made materials with complex architectures for a variety of applications. Herein, a kinetic study on the self‐assembly of spindle‐like micelles preassembled from polypeptide graft copolymers is reported. The addition of dimethylformamide and, subsequently, a selective solvent (water) can generate a “reactive point” at both ends of the spindles as a result of the existence of structural defects, which induces the “polymerization” of the spindles into nanowires. Experimental results combined with dissipative particle dynamics simulations show that the polymerization of the micellar subunits follows a step‐growth polymerization mechanism with a second‐order reaction characteristic. The assembly rate of the micelles is dependent on the subunit concentration and on the activity of the reactive points. The present work reveals a law governing the self‐assembly kinetics of micelles with structural defects and opens the door for the construction of hierarchical structures with a controllable size through supramolecular step polymerization.
Infections and the relationship to treatment in neuromuscular autoimmunity
Authors: Prior Devin E. , Nurre Emily , Roller Stephanie L. , Kline David , Panara Ramit , Stino Amro M. , Davis John A. , Freimer Miriam L. , Arnold W. David
Published: December 2017

Introduction: This study aimed to identify infections in patients with myasthenia gravis, dermatomyositis, and chronic inflammatory demyelinating polyradiculoneuropathy, and to investigate the relationship between infection and immunomodulation. Methods: A retrospective chart review examined 631 patients with myasthenia gravis (n = 358), chronic inflammatory demyelinating polyradiculoneuropathy (n = 124), and dermatomyositis (n = 149) patients over a 10‐year time period. Results: Infection rates were similar at approximately 19% in all 3 diseases. Of the infections in which a causative organism was identified, pneumonia, sepsis, and opportunistic infections were the leading diagnoses. A multivariate model demonstrated a significant association between infection and an increased dose of plasma exchange, mycophenolate mofetil, and corticosteroid therapy. Discussion: There are few large studies investigating rates of infections in patients with autoimmune neuromuscular disorders and the relationship to immunomodulation. This study not only demonstrates the remarkably similar infection rates across the 3 diseases studied, but also shows their relationship to commonly used immunotherapies. Muscle Nerve 57: 927–931, 2018
Miconazole enhances nerve regeneration and functional recovery after sciatic nerve crush injury
Authors: Lin Tao , Qiu Shuai , Yan Liwei , Zhu Shuang , Zheng Canbin , Zhu Qingtang , Liu Xiaolin
Published: December 2017

Introduction: Improving axonal outgrowth and remyelination is crucial for peripheral nerve regeneration. Miconazole appears to enhance remyelination in the central nervous system. In this study we assess the effect of miconazole on axonal regeneration using a sciatic nerve crush injury model in rats. Methods: Fifty Sprague‐Dawley rats were divided into control and miconazole groups. Nerve regeneration and myelination were determined using histological and electrophysiological assessment. Evaluation of sensory and motor recovery was performed using the pinprick assay and sciatic functional index. The Cell Counting Kit‐8 assay and Western blotting were used to assess the proliferation and neurotrophic expression of RSC 96 Schwann cells. Results: Miconazole promoted axonal regrowth, increased myelinated nerve fibers, improved sensory recovery and walking behavior, enhanced stimulated amplitude and nerve conduction velocity, and elevated proliferation and neurotrophic expression of RSC 96 Schwann cells. Discussion: Miconazole was beneficial for nerve regeneration and functional recovery after peripheral nerve injury. Muscle Nerve 57: 821–828, 2018
Estimating the global prevalence of transthyretin familial amyloid polyneuropathy
Authors: Schmidt Hartmut H. , Waddington‐Cruz Márcia , Botteman Marc F. , Carter John A. , Chopra Avijeet S. , Hopps Markay , Stewart Michelle , Fallet Shari , Amass Leslie
Published: December 2017

Introduction: This study sought to estimate the global prevalence of transthyretin familial amyloid polyneuropathy (ATTR‐FAP). Methods: Prevalence estimates and information supporting prevalence calculations was extracted from records yielded by reference‐database searches (2005–2016), conference proceedings, and nonpeer reviewed sources. Prevalence was calculated as prevalence rate multiplied by general population size, then extrapolated to countries without prevalence estimates but with reported cases. Results: Searches returned 3,006 records; 1,001 were fully assessed and 10 retained, yielding prevalence for 10 “core” countries, then extrapolated to 32 additional countries. ATTR‐FAP prevalence in core countries, extrapolated countries, and globally was 3,762 (range 3639–3884), 6424 (range, 1,887–34,584), and 10,186 (range, 5,526–38,468) persons, respectively. Discussion: The mid global prevalence estimate (10,186) approximates the maximum commonly accepted estimate (5,000–10,000). The upper limit (38,468) implies potentially higher prevalence. These estimates should be interpreted carefully because contributing evidence was heterogeneous and carried an overall moderate risk of bias. This highlights the requirement for increasing rare‐disease epidemiological assessment and clinician awareness. Muscle Nerve 57: 829–837, 2018
Feasibility of 7T MRI for imaging fascicular structures of peripheral nerves
Authors: Yoon Daehyun , Biswal Sandip , Rutt Brian , Lutz Amelie , Hargreaves Brian
Published: December 2017

Introduction: Evaluation of the nerve fascicular structure can be useful in diagnosing nerve damage, but it is a very challenging task with 3T MRI because of limited resolution. In this pilot study, we present the feasibility of high‐resolution 7T MRI for examining the nerve fascicular structure. Methods: A 3‐dimensional (3D) gradient‐spoiled sequence was used for imaging peripheral nerves in extremities. Images acquired with different in‐plane resolutions (0.42 × 0.42 mm vs. 0.12 × 0.12 mm), and different main field strengths (7T vs. 3T) were compared. Results: The individual nerve fascicles were identified at 0.12 × 0.12 mm resolution in both field strengths but not at 0.42 × 0.42 mm resolution. The fascicular structure was more sharply depicted in 7T images than in 3T images. Discussion: High‐resolution 3D imaging with 7T MRI demonstrated feasibility for imaging nerve fascicular structures. Muscle Nerve 57: 494–498, 2018
Rhodol Derivatives as Selective Fluorescent Probes for the Detection of HgII Ions and the Bioimaging of Hypochlorous Acid
Authors: Li Ling , Wang Shu , Lan Hongxia , Gong Guiyi , Zhu Yifan , Tse Yu Chung , Wong Keith Man‐Chung
Published: December 2017

Two sensors, 1 with a spirolactone group and 2 with a spirolactam group containing a phenyl isothiocyanate moiety, based on rhodol, were designed and synthesized in order to obtain materials with excellent optical properties for the detection of environmentally and biologically important Hg2+ and hypochlorous acid (HClO) ions. The crystal structure of 1 revealed two moieties, a rhodamine‐like portion with a spirolactone and a fluorescein‐like portion without a spirolactone. In the absence of analyte, 1 produced an optical output with a maximum absorption and emission at 475 and 570 nm, respectively, which was attributed to the fluorescein‐like moiety without a spirolactone. In contrast, the rhodamine‐like moiety containing a spirolactone was activated by the addition of H+ or Hg2+ ions, and 1 yielded new absorption and emission peaks at 530 and 612 nm, respectively. Further functionalization with a phenyl isothiocyanate group afforded 2, a fluorescent probe for HClO. High selectivity and sensitivity towards the hypochlorite ion were anticipated, owing to the stoichiometric and irreversible formation of a thiosemicarbazide group, which led to dramatic fluorescence responses. With good functionality at physiological pH, probe 2 was successfully used to image HClO in HeLa cells.
Synthesis and mechanical properties of dopamine modified titanium dioxide/waterborne polyurethane composites
Authors: Deng Feifei , Zhang Yuliang , Li Xia , Liu Yawei , Shi Zhiqing , Wang Yinghan
Published: December 2017

Environmentally friendly waterborne polyurethane (WPU) films were functionalized by incorporating nano‐titanium dioxide (TiO2). In order to improve the dispersion of TiO2 in the WPU matrix and intensify the interfacial interaction between TiO2 and WPU, green and biocompatible dopamine (DA) modified TiO2, that is, DA‐TiO2, was produced. Fourier transforms infrared (FTIR) and UV‐vis spectra confirmed that DA had been successfully grafted on the surface of TiO2. The structure, mechanical and thermal properties of WPU/DA modified TiO2 (WPU/DA‐TiO2) films had been carefully investigated using FTIR, transmission electron microscopy (TEM), X‐ray diffraction (XRD), tensile experiments and thermogravimetric analysis (TGA). The tensile strength and elongation at break of WPU/DA‐TiO2 containing 1 wt% DA‐TiO2 increased by 56.8% and 37.0%, respectively, compared to pure WPU. These results can be ascribed to the good dispersion of DA‐TiO2 and the strong interfacial interaction between DA‐TiO2 and WPU matrix. In addition, the thermal properties and water resistance of WPU/DA‐TiO2 films also had been improved. POLYM. COMPOS., 40:328–336, 2019. © 2017 Society of Plastics Engineers
Strong subbandgap photoconductivity in GaP implanted with Ti
Authors: Olea Javier , del Prado Alvaro , García‐Hemme Eric , García‐Hernansanz Rodrigo , Montero Daniel , González‐Díaz German , Gonzalo Jose , Siegel Jan , López Esther
Published: December 2017

Photovoltaic solar cells based on the intermediate band (IB) concept could greatly enhance the efficiency of future devices. We have analyzed the electrical and photoconductivity properties of GaP supersaturated with Ti to assess its suitability for IB solar cells. GaP:Ti was obtained by ion implantation followed by pulsed‐laser melting (PLM) using an ArF excimer laser. It was found that PLM energy densities between 0.35 and 0.55 J/cm2 produced a good recovery of the crystalline structure of GaP (both unimplanted and implanted with Ti), as evidenced by high mobility measured values (close to the reference GaP). Outside this energy density window, the PLM failed to recover the crystalline structure producing a low mobility layer that is electrically isolated from the substrate. Spectral photoconductivity measurements were performed by using the van der Pauw set up. For GaP:Ti a significant enhancement of the conductivity was observed when illuminating the sample with photon energies below 2.26 eV, suggesting that this photoconductivity is related to the presence of Ti in a concentration high enough to form an IB within the GaP bandgap. The position of the IB was estimated to be around 1.1 eV from the conduction band or the valence band of GaP, which would lead to maximum theoretical efficiencies of 25% to 35% for a selective absorption coefficients scenario and higher for an overlapping scenario.
A Comparative Study of InGaN/GaN Multiple‐Quantum‐Well Solar Cells Grown on Sapphire and AlN Template by Metalorganic Chemical Vapor Deposition
Authors: Miyoshi Makoto , Ohta Miki , Mori Takuma , Egawa Takashi
Published: December 2017

Two kinds of substrates, sapphire and AlN/sapphire template (AlN template), are used for the growth of InGaN/GaN multi‐quantum‐well solar cell structures by metalorganic chemical vapor deposition, and their material and device properties are investigated. The results show that the samples grown on AlN template have a better crystal quality with a larger in‐plane compressive strain than those on sapphire, and solar cells fabricated on sapphire mostly exhibit better performance than those on AlN template. An analysis of the photoluminescence measurements indicates that a critical InGaN well thickness related to the generation of nonradiative recombination centers, which affects the internal and external quantum efficiencies, is thinner in samples grown on AlN template than in samples on sapphire. The critical thickness is speculated to be related to the large in‐plane compressive strain in the samples on AlN template. By contrast, in comparison between samples with a sufficiently thin InGaN well thickness of 1.0 nm, the sample on AlN template exhibits better solar cell performance than on sapphire. This implies that the improved crystal quality contributes to the improvement of internal quantum efficiency as long as the well layer is thinner than the critical thickness.
Electrical and Optical Properties of Rectifying ZnO Homojunctions Fabricated by Wet Chemistry Methods
Authors: Yatskiv Roman , Tiagulskyi Stanislav , Grym Jan , Cernohorsky Ondrej
Published: December 2017

Rectifying ZnO homojunctions are fabricated by simple wet chemistry methods. The p–n junction is formed between a p‐type nanostructured seed layer deposited by sol–gel method on phosphorus doped Si substrates and an array of n‐type nanorods grown by chemical bath deposition. The p‐type conductivity in the nanostructured layer is achieved by thermal diffusion of phosphorus from the Si substrate. The diffusion of phosphorus is supported by the observation of optical transitions related to neutral acceptor bound exciton in low‐temperature photoluminescence spectra. The p–n junction shows a high value of rectification ratio. Charge transport through the p‐n junction is discussed in terms of non‐ideal interface.
Ultrathin AlN‐Based HEMTs Grown on Silicon Substrate by NH3‐MBE
Authors: Rennesson Stephanie , Leroux Mathieu , Al Khalfioui Mohamed , Nemoz Maud , Chenot Sébastien , Massies Jean , Largeau Ludovic , Dogmus Ezgi , Zegaoui Malek , Medjdoub Farid , Semond Fabrice
Published: December 2017

AlN‐based HEMTs grown on silicon by ammonia‐assisted molecular beam epitaxy (NH3‐MBE) are demonstrated and studied. As shown by photoluminescence, the very thin GaN channel (35–55 nm‐thick) is compressively strained on the 250 nm‐thick relaxed AlN buffer layer grown on silicon substrate. The structure is then completed by an 8 nm‐thick AlN barrier and 2 nm‐thick GaN cap. Despite an ultrathin total epilayer (only ≈300 nm‐thick), a high 2DEG density (≈2.7 × 1013 cm−2) is measured by Hall effect. Room temperature mobility values, as high as 636 cm2 V−1 s−1, are measured. They are higher than those reported on similar structures grown on sapphire, SiC and bulk AlN substrates, showing the interest of growing such structures on silicon substrate. Also, low contact resistance values are obtained, as low as 0.18 Ω mm, by using a basic fabrication process.
Investigation of the GaN/Al2O3 Interface by First Principles Calculations
Authors: Chokawa Kenta , Kojima Eiji , Araidai Masaaki , Shiraishi Kenji
Published: December 2017

Metal–oxide–semiconductor field effect transistors (MOSFETs) based on GaN have been studied for high‐power performance because of the wide bandgap of GaN. Although Al2O3 is a promising dielectric film for GaN power devices, the interface structure of GaN/Al2O3 has not been revealed microscopically. We prepared two interface models with Ga–O bonds and Ga–Al bonds at the interface. Because the Ga–O bond is stronger than the Ga–Al bond, the Ga–O bonds are preferentially formed at the interface. When the Ga–Al bonds appear at the interface, they introduce defect levels in the bandgap of GaN. On the other hand, when the interface consists of Ga–O bonds, some defect structures can appear depending on the oxygen density. In oxygen‐rich conditions, dangling bonds appear at the N atoms and their states appear around the valence band maximum.
Alantolactone, a sesquiterpene lactone, inhibits breast cancer growth by antiangiogenic activity via blocking VEGFR2 signaling
Authors: Liu Ya‐Rong , Cai Qin‐Yi , Gao Yun‐Ge , Luan Xin , Guan Ying‐Yun , Lu Qin , Sun Peng , Zhao Mei , Fang Chao
Published: December 2017

Alantolactone (ALA), a sesquiterpene lactone isolated from several medicinal plants such as Inula helenium, has been identified to have attractive anticancer activity. However, its role in the inhibition of angiogenesis during tumor development remains unclear. In this study, we found ALA can inhibit the proliferation, motility, migration, and tube formation of human umbilical vein endothelial cells. ALA also restrained angiogenesis in chick embryo chorioallantoic membrane and delayed the growth of human MDA‐MB‐231 breast cancer xenograft in mice through angiogenesis inhibition. Furthermore, ALA suppressed the phosphorylation of vascular endothelial growth factor receptor 2 and its downstream protein kinase including PLCγ1, FAK, Src, and Akt in endothelial cells. Taken together, the antiangiogenic activity of ALA and its molecular mechanism are identified for the first time, indicating that ALA may be a potential drug candidate or lead compound for antiangiogenic cancer therapy.
Arboviruses and their related infections in China: A comprehensive field and laboratory investigation over the last 3 decades
Authors: Liang Guodong , Li Xiaolong , Gao Xiaoyan , Fu Shihong , Wang Huanyu , Li Minghua , Lu Zhi , Zhu Wuyang , Lu Xinjun , Wang Lihua , Cao Yuxi , He Ying , Lei Wenwen
Published: December 2017

Since the 1980s, a comprehensive field and laboratory investigation has been conducted throughout China, and a total of 29 virus species belonging to 7 families and 13 genera were identified through virological, morphological, and immunological methods, as well as whole‐genome sequencing and molecular genetic analyses. Most of the virus isolates belong to 9 genera in the families Flaviviridae, Bunyaviridae, Togaviridae, and Reoviridae. Among them, 4 genera (Orthobunyavirus, Bunyavirus, Phlebovirus, and Nairovirus) belong to the family Bunyaviridae and 3 genera (Seadonavirus, Orbivirus, and Cypovirus) belong to the family Reoviridae. Analyses of the relationships between viruses and human/animal diseases indicated that Japanese encephalitis virus, dengue virus, severe fever with thrombocytopenia syndrome virus, tick‐borne encephalitis virus, Crimean‐Congo hemorrhagic fever virus, West Nile virus, and Tahyna virus can cause human and animal infections and disease epidemics in China.

This review systematically introduces the current status of the diversity and geographical distribution of arboviruses and vectors in China. In addition, our results provide strong technical support for the prevention and control of arboviral diseases, the treatment of epidemics, and the early warning and prediction of diseases, and so they are significant for the control and prevention of arboviral diseases in Asia and around the world.
A Trifunctional Linker for Purified 3D Assembled Peptide Structure Arrays
Authors: Mattes Daniela S. , Rentschler Simone , Foertsch Tobias C. , Münch Stephan W. , Loeffler Felix F. , Nesterov‐Mueller Alexander , Bräse Stefan , Breitling Frank
Published: December 2017

Microarrays are an important tool in modern research that allow the rapid screening of many different interactions simultaneously. Peptide arrays, which bear different peptides arranged in separate spots, permit high‐throughput screening to investigate linear and cyclic binding sites. To study conformational or discontinuous binding sites, protein arrays are the major choice. However, the tremendous costs for the generation of high‐density protein arrays of high purity restrict progress in protein research. Therefore, peptide‐based arrays, which can mimic assembled peptide structures, have an enormous potential. Here, a method is presented to create such structures in the array format as an alternative to protein arrays. A trifunctional linker is developed with an azide, a protected alkyne, and a carboxyl group, which can react with two or three different peptides. Due to the spatial proximity, the peptides interact and can form an assembled peptide structure. As a proof of concept, assembled peptide structures are demonstrated on beads and on a polymer surface and the approach can be validated via matrix‐assisted laser desorption/ionization spectrometry. Furthermore, a multistep transfer of peptide arrays is shown, generating purified assembled peptide structure arrays in high density.
Photovoltaic Properties of a Porphyrin‐Containing Polymer as Donor in Bulk Heterojunction Solar Cells With Low Energy Loss
Authors: Bucher Léo , Tanguy Loïc , Desbois Nicolas , Karsenti Paul‐Ludovic , Harvey Pierre D. , Gros Claude P. , Sharma Ganesh D.
Published: December 2017

A low bandgap D‐π‐A polymer (PPDPP; D = Zn‐porphyrin, A = diketopyrrolopyrrole, π = ethynyle linker) has been synthesized and used as an electron donor for the fabrication of solution processed bulk heterojunction polymer solar cells (PSCs). PC71BM is used as the electron acceptor. After the optimization of the PPDPP: PC71BM weight ratio in 2‐methyltetrahydrofuran (2‐MeTHF), the PSC based on PPDPP: PC71BM (1:2) showed an overall power conversion efficiency (PCE) of 4.18% with Jsc = 9.75 mA cm−2, Voc = 0.78 V, and FF = 0.54. After the thermal annealing (TA) and subsequent solvent vapor annealing (SVA) of the active layer, the resulting device showed an overall PCE of 6.44% (Jsc = 13.18 mA cm−2, Voc = 0.74 V, and FF = 0.66) with a small voltage loss of 0.51 eV. The improvement in PCE after the TA and SVA treatment of the active layer is attributed to an enhancement of Jsc and FF related to a more favorable nanoscale morphology for the exciton dissociation and charge transport as evidenced by the increased hole mobility.
Analysis and suppression measures of lightning transient overvoltage in the signal cable of wind turbines
Authors: Yang Qing , Tao Jiayuan , He Yanxiao , Zhang Bo
Published: December 2017

Lightning strikes are a major threat to the secure operation of wind turbines. When lightning strikes a wind turbine, the lightning current flows through the blade and the tower and then the induced overvoltage will damage sensors and signal cables. In this study, a comprehensive transient surge impedance model of a wind turbine was built to analyze the causes of the overvoltage in the signal cable. The model that studies the overvoltage caused by both capacitive coupling and electromagnetic induction included the blade, nacelle, tower, signal cable, power cable, and grounding system using π networks. The influences of the cable shielding layer, soil resistivity, and lightning current waveform on the overvoltage were also analyzed. Then, 2 overvoltage suppression measures, ie, grounding at 2 ends of the outer shielding layer and installation of a surge protective device, were tested. Results show that a signal cable with double shielding layers reduced the overvoltage in the signal cable, and higher soil resistivity resulted in increased voltage on the tower base. In addition, the peak and the front time of the lightning current significantly influenced the overvoltage on the tower and the cable. The effectiveness of the 2 suppression measures was also verified. The calculation results will provide guidance for a reasonable lightning protection design.
Operative outcome of liver resections for hepatocellular carcinoma: Retrospective case control study of a twelve-years pioneer experience in the Sudan
Authors: Elsanousi Osama Mohamed , Mohamed Murtada Abdellatief , Fadl Amira Abbas
Published: December 2017

ABSTRACT

Introduction:

Modern liver surgery in the Sudan started at our institution, The National Ribat University Hospital, in 2002. This study aimed to assess the perioperative events of hepatocellular carcinoma (HCC) resection in our institution during the period January 2002 to December 2013 compared to hepatectomies for benign liver pathologies.

Methods:

The medical records of 114 patients subjected to hepatectomy were divided into the HCC group (cases), and benign group (controls). The characteristics and perioperative events of both groups were assessed and compared.

Results:

The mean age of the HCC patients was 58.6 ± 7.7 years. The majority of liver resections in the HCC group were minor (72.7%). The mean intraoperative blood loss was 918.8 ml in the HCC group and 720 ml in benign resections group and the difference between them was not significant, p = 0.129. The mean operative duration of HCC resection was 4 hours. The major postoperative complications were encountered in 16 patients (36.4%) in the HCC group. HCC group thirty-day postoperative mortality was 9.1%, (n = 4 patients) while no patient of the benign group (n = 60) died within that duration, p = .030. Logistic regression multivariate analysis revealed massive bleeding as an independent predictor for major postoperative morbidity, Odds ratio [OR] = 5.899, 95%, Confidence Interval [95% CI], 1.129–30.830, p = .035.

Discussion:

Our results revealed outcome parameters comparable with the international reports.

Conclusion:

Further improvements in hepatic surgery in general, and HCC in particular is inevitable.

Highlights:
Sleep-Related Painful Erections: A Meta-Analysis on the Pathophysiology and Risks and Benefits of Medical Treatments
Authors: Vreugdenhil Sanne , Weidenaar Alida Cornelia , de Jong Igle Jan , van Driel Mels Frank
Published: December 2017

Background

Patients with sleep-related painful erections (SRPEs) have frequent awakenings from deep penile pain during nocturnal erections. This results in severe sleep deprivation.

Aim

To review the current literature on SRPEs and discuss the pathophysiologic theories and risks and benefits of medical treatments.

Methods

PubMed was searched using the terms sleep-related painful erections, nocturnal priapism, treatment, and sleep-related erections.

Outcome

Variables included patient demographics, medical history, diagnostics, hypotheses on pathophysiology, and treatment modalities and their effect on SRPE in the short and long term.

Results

The search yielded in 66 SRPE cases that were analyzed, including our mono-institutional series of 24 patients. The phenomenon of SRPEs is not well understood. Theories about pathophysiology concerned increased serum testosterone levels, altered autonomic function, compression of the lateral preoptic area, coexistent obstructive sleep apnea syndrome, the existence of a “compartment syndrome,” and psychosomatic factors. Except for polysomnographic findings that showed sleep fragmentation and decreased sleep efficiency in all patients, other diagnostic results varied widely. Multiple agents were tried. Baclofen and, to lesser degree, clonazepam showed noticeable results, most likely due to their influence on the γ-aminobutyric acid system and, hence, suppression of glutamate release. In addition, baclofen relaxes the ischiocavernosus and bulbospongiosus muscles, which are involved in penile erection.

Clinical Implications

By providing a critical analysis and complete overview on the limited literature about this overlooked and undermanaged condition, this review contributes to a better understanding of the pathophysiology and provides directions for future research on the treatment of SRPE.

Strengths and Limitations

Because the literature on SRPEs includes only case reports and small case series, the level of evidence of treatment advice is limited.

Conclusion

The pathophysiology of SRPEs is not yet clarified. Further diagnostic evaluation, including electromyography of the ischiocavernosus and bulbospongiosus muscles to elucidate the pathophysiology, is recommended. Prospective controlled investigations are warranted to assess the efficacy and safety of long-term use of baclofen and develop evidence-based treatment advice.
Recent deposition environments in the Chukchi Sea and adjacent areas of the Arctic Ocean: Evidence from Q-cluster analysis of sediment compositions and grain sizes
Authors: Kolesnik A.N. , Astakhov A.S. , Kolesnik O.N.
Published: December 2017

Deposition environments in the Chukchi Sea and adjacent areas of the Arctic Ocean are studied by the Q-cluster analysis of compositions, particle sizes, and other properties of surface bottom sediments. Analysis of more than 4700 numeric values allowed mapping fifteen clusters distributed over the seafloor according to deposition environments. Chemical and statistical data confirm the predominance of clastic sedimentation and mainly mechanic sorting of sedimentary material. At the same time, the major-element composition trends correspond to Si decrease and Al increase seaward. Biogenic deposition is of inferior scale and shows up as relative enrichment in total organic carbon, Ca, Mg, Ba, Sr, and some other biogenic and chemogenic components in sediments. Clastic and biogenic deposition, with accumulation of Fe, Mn, V, Ni, Cr, Co, and other elements, as well as precipitation of authigenic phases, occurs within areas of seafloor having particular water chemistry, such as the Herald Canyon, the outer shelf, and the deepwater Arctic Ocean.
Hydrogeochemical earthquake precursor in the southern Baikal region
Authors: Semenov R.M. , Kashkovskii V.V. , Lopatin M.N.
Published: December 2017

This paper presents the results of study of seismically induced variations in helium concentration in groundwater in the southern Baikal region. Unlike previous studies, data were obtained not only in Baikal deepwater but also in artesian wells in the southern Baikal region. The correlation coefficients between the data obtained at these observation stations, indicator functions, and an integrated indicator functions were calculated. They provide an objective assessment of time variations in concentrations due to changes in the stress–strain state of the Earth’s crust related to earthquake preparation and hence permit one to predict the time of an earthquake.
Thermomagnetic analysis of native iron from the upper sedimentary horizons of Lake Baikal, section GC-99 (Posolskaya Bank)
Authors: Pechersky D.M. , Kuzina D.M. , Ivanov E.V. , Kuz’min M.I. , Nurgaliev D.K. , Tsel’movich V.A.
Published: December 2017

We present results of a thermomagnetic analysis of Late Pleistocene–Holocene bottom sediments from the gravity core GC-99 of the borehole BDP-99 drilled at Posolskaya Bank of Lake Baikal in the framework of the Baikal Drilling Project. The results are compared with the earlier analytical data on the samples from the lower (Miocene) section of the BDP-98 drilled on the Akademichesky Ridge. Native-iron particles were found in only 14 of 61 samples. Their content varies from ~ 10–5 to 10–4%, and their distribution is near-bimodal, with a distinct “zero” mode. The results of the thermomagnetic analysis are confirmed by a probe microanalysis: Only occasional native-iron particles were found. Nickel was detected in only one sample. The samples have a large number of magnetite and titanomagnetite grains. It is shown that the distribution of native-iron particles in the Baikal sediments depends on the rate of sedimentation: The rate increase is accompanied by the increase in the number of the “zero” group samples (free of iron particles). The conclusion is drawn that the native-iron particles in the studied sediments are predominantly of cosmic origin.
Mixing laws and causality in high frequency induction log applications
Authors: Tabarovsky L. , Forgang S.
Published: December 2017

High frequency electromagnetic technologies for subsurface formation evaluation provide high spatial resolution and new opportunities for petrophysical interpretation of data. Dispersion of rock properties and up-scaling from pore to reservoir scale (homogenization) represent the two most challenging problems. In electrodynamics of porous media, various mixing and dispersion laws are used to homogenize rock properties and describe their frequency behavior. Mixing laws and dispersion have a close link to the fundamental physical principle of causality and therefore cannot be introduced arbitrarily. For any mixing/dispersion law, we need to prove that causality holds. For testing causality, we use Titchmarsh’s theorem and, particularly, one of its modifications—Kramers–Kronig relations. Causality is discussed for Debye, Cole–Cole, Havriliak–Negami, and CRIM models. Dispersion is closely related to wave propagation. Evaluation of phase and group velocities shed new light on the physics of phase and amplitude measurements in lossy media. We evaluated various definitions of both velocities and their dependence on spatial spectra or, in other words, on the arrangement of transmitting and receiving elements. To illustrate theoretical findings, we use dielectric logging as an exemplary technology. Usually, in modern dielectric tools, amplitude and phase data are acquired, for various frequencies and sensor positions. The measured phase is discontinuous at high frequencies and requires detection of discontinuity as well as unwrapping. Remarkably, one can determine formation attenuation and loss angle based on multifrequency/multisensor amplitude data and transform them into dielectric permittivity, resistivity, and true continuous phase. Transformations of exemplary tool data used in this paper are suitable for a conceptual study and are specific for a uniform formation. We intentionally do not address the accuracy of measurements and propagation of errors in the inversion process, since they are tool- and processing-specific. Different tools require joint analysis of all available data and special noise reduction techniques associated with the structure of the acquisition system.