bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct Synthesis of Enolizable N‐Sulfonyl Ketimines Under Microwave Irradiation
Authors: Pablo Ortiz  , Collados Juan F. , Harutyunyan Syuzanna R. 
Published: February 2016

AbstractN‐sulfonyl imines are widely used as substrates for a range of transformations. Access to N‐sulfonyl aldimines is straightforward through direct condensation between the parent aldehyde and the sulfonamide. However, this approach is not efficient for the synthesis of enolizable N‐sulfonyl ketimines. Herein we report a rapid and facile methodology for obtaining these products using microwave irradiation.
Azaphosphatranes as Hydrogen‐Bonding Organocatalysts for the Activation of Carbonyl Groups: Investigation of Lactide Ring‐Opening Polymerization
Authors: Zhang Dawei , Jardel Damien , Peruch Frédéric , Calin Nathalie , Dufaud Véronique , Dutasta Jean‐Pierre , Martinez Alexandre , Bibal Brigitte 
Published: February 2016

AbstractThe hydrogen‐bonding activation of C=O bonds by azaphosphatranes was explored in a model reaction, i.e., the ring‐opening polymerization of lactide. The polymerization process was controlled, and allowed the preparation of polylactides with narrow dispersity under mild conditions (20 °C, 24 h, 10 mol‐% catalyst loading). Interestingly, the steric hindrance of azaphosphatranes, as globular rigid structures, prevents any undesired interaction with the tertiary amine cocatalysts, as shown by X‐ray analysis and semi‐empirical calculations. In contrast to their organocatalytic activity in the CO2/epoxide reaction, all of the phosphonium derivatives tested were found to be efficient catalysts in this ROP benchmark reaction.
Electrochemistry on Paper‐based Analytical Devices: A Review
Authors: Mettakoonpitak Jaruwan , Boehle Katherine , Nantaphol Siriwan , Teengam Prinjaporn , Adkins Jaclyn A. , Srisa‐Art Monpichar , Henry Charles S. 
Published: February 2016

AbstractEven though they were introduced less than a decade ago, electrochemical paper‐based devices (ePADs) have attracted widespread attention because of their inherent advantages in many applications. ePADs combine the advantages of microfluidic paper‐based devices (low cost, ease of use, equipment free pumping, etc.) for sample handling and processing with the advantages of sensitive and selective detection provided by electrochemistry. As a result, ePADs provide simplicity, portability, reproducibility, low cost and high selectivity and sensitivity for analytical measurements in a variety of applications ranging from clinical diagnostics to environmental sensing. Herein, recent advances in ePAD development and application are reviewed, focusing on electrode fabrication techniques and examples of applications specially focused on environmental monitoring, biological applications and clinical assays. Finally, a summary and prospective directions for ePAD research are also provided.
High‐throughput microfluidic device for single cell analysis using multiple integrated soft lithographic pumps
Authors: Patabadige Damith E. W. , Mickleburgh Tom , Ferris Lorin , Brummer Gage , Culbertson Anne H. , Culbertson Christopher T. 
Published: February 2016

The ability to accurately control fluid transport in microfluidic devices is key for developing high‐throughput methods for single cell analysis. Making small, reproducible changes to flow rates, however, to optimize lysis and injection using pumps external to the microfluidic device are challenging and time‐consuming. To improve the throughput and increase the number of cells analyzed, we have integrated previously reported micropumps into a microfluidic device that can increase the cell analysis rate to ∼1000 cells/h and operate for over an hour continuously. In order to increase the flow rates sufficiently to handle cells at a higher throughput, three sets of pumps were multiplexed. These pumps are simple, low‐cost, durable, easy to fabricate, and biocompatible. They provide precise control of the flow rate up to 9.2 nL/s. These devices were used to automatically transport, lyse, and electrophoretically separate T‐Lymphocyte cells loaded with Oregon green and 6‐carboxyfluorescein. Peak overlap statistics predicted the number of fully resolved single‐cell electropherograms seen. In addition, there was no change in the average fluorescent dye peak areas indicating that the cells remained intact and the dyes did not leak out of the cells over the 1 h analysis time. The cell lysate peak area distribution followed that expected of an asynchronous steady‐state population of immortalized cells.
Farnesol stimulates laccase production in Trametes versicolor
Authors: Hu Jianhua , Wang Feng , Ma Anzhou , Zhuang Guoqiang , Liu Ying , Lu Jingsong , Guo Chen , Liu Chunzhao 
Published: February 2016

Farnesol, a quorum‐sensing molecule, was used successfully to improve laccase production in submerged cultures of Trametes versicolor. At the optimal farnesol concentration of 60 μM added at the beginning of the culture, the extracellular laccase activity reached 629.3 U L−1 after 6 days of cultivation, which represented a 1.92‐fold increase relative to the control without farnesol treatment. The addition of farnesol resulted in an increase in the accumulation of H2O2 and an increased expression of the laccase (lac) gene and the RhoA gene. The RhoA gene correlated with hyperbranched mycelia, which facilitated the secretion of the intracellular laccase. This study provides a basis for understanding the induction mechanism of farnesol for enhancing laccase production.
A novel power control based on a relaxed constraint in cognitive system
Authors: Ridouani Mohammed , Hayar Aawatif , Haqiq Abdelkrim 
Published: February 2016

AbstractThe next‐generation 5G networks will integrate two technologies, cognitive radio and cooperative communication, which use radio spectrum opportunistically and efficiently. In addition, they enhance the reliability and the capacity of the system. In this paper, we present a novel power control scheme based on a relaxed constraint in cognitive network under both the outage probability limit (OPL) of the primary system and the interference constraint limit (ICL). We show how to transform the optimization problem of the condition on the OPL and the ICL into a condition on the channel so that the cognitive user observes the channel from cognitive source to primary receiver and control its transmit power based on the channel condition. Moreover, we extend the studies to the cognitive relay network. We derive the closed‐form expressions of the outage probabilities over independent but not necessarily identically distributed Nakagami‐m fading channels. By using the theoretical analysis and from the numerical results, firstly, we show that the proposed power control scheme, which is based on both the OPL and the ICL, achieves better performance in underlay spectrum rather than the traditional one, which is based only on the interference constraints. Secondly, we show that the proposed scheme allows lower power consumption at cognitive side while the performance of cognitive relay network is improved, and the QoS of primary system is guaranteed in parallel. Copyright © 2016 John Wiley & Sons, Ltd.
3D seismic structure of the Zhenbei–Huangyan seamounts chain in the East Sub‐basin of the South China Sea and its mechanism of formation
Authors: Wang Jian , Zhao Minghui , Qiu Xuelin , Sibuet Jean‐Claude , He Enyuan , Zhang Jiazheng , Tao Chunhui 
Published: February 2016

AbstractThe probable N055°‐oriented extinct spreading ridge of the East Sub‐basin is cut across by the post‐spreading volcanic ridge oriented approximately E–W in its western part and called the Zhenbei–Huangyan seamounts chain. A three‐dimensional ocean bottom seismometer survey was conducted in 2011 and covered both the extinct spreading ridge and the Zhenbei–Huangyan seamounts chain in the East Sub‐basin. The comprehensive seismic record sections of 39 ocean bottom seismometers underline the high‐quality data with clear and reliable P‐wave seismic first arrivals. The three‐dimensional tomographic results show that the crust is oceanic on each side of the Zhenbei–Huangyan seamounts chain. The seafloor spreading lineaments and associated fracture zones pattern provide channels for magma migration and eruption. Based on the ratio of volcanic extrusive and intrusive materials and the shape of the upward convex 6.4 km/s iso‐velocity curve beneath the Zhenbei and Huangyan seamounts, we conclude that the Zhenbei and Huangyan seamounts appear to be dominantly formed by intra‐crustal intrusion. Combining previous geochemical studies of post‐spreading volcanic ridge outcropping samples, the formation mechanism of the seamounts chain might be explained by a buoyancy‐driven decompression melting mechanism occurring as separately evolving partial melting bodies beneath each seamount. Copyright © 2016 John Wiley & Sons, Ltd.
Preprocessing strategy influences graph‐based exploration of altered functional networks in major depression
Authors: Borchardt Viola , Lord Anton Richard , Li Meng , van der Meer Johan , Heinze Hans‐Jochen , Bogerts Bernhard , Breakspear Michael , Walter Martin 
Published: February 2016

AbstractResting‐state fMRI studies have gained widespread use in exploratory studies of neuropsychiatric disorders. Graph metrics derived from whole brain functional connectivity studies have been used to reveal disease‐related variations in many neuropsychiatric disorders including major depression (MDD). These techniques show promise in developing diagnostics for these often difficult to identify disorders. However, the analysis of resting‐state datasets is increasingly beset by a myriad of approaches and methods, each with underlying assumptions. Choosing the most appropriate preprocessing parameters a priori is difficult. Nevertheless, the specific methodological choice influences graph‐theoretical network topologies as well as regional metrics. The aim of this study was to systematically compare different preprocessing strategies by evaluating their influence on group differences between healthy participants (HC) and depressive patients. We thus investigated the effects of common preprocessing variants, including global mean‐signal regression (GMR), temporal filtering, detrending, and network sparsity on group differences between brain networks of HC and MDD patients measured by global and nodal graph theoretical metrics. Occurrence of group differences in global metrics was absent in the majority of tested preprocessing variants, but in local graph metrics it is sparse, variable, and highly dependent on the combination of preprocessing variant and sparsity threshold. Sparsity thresholds between 16 and 22% were shown to have the greatest potential to reveal differences between HC and MDD patients in global and local network metrics. Our study offers an overview of consequences of methodological decisions and which neurobiological characteristics of MDD they implicate, adding further caution to this rapidly growing field. Hum Brain Mapp 37:1422‐1442, 2016. © 2016 Wiley Periodicals, Inc.
Early developmental gene enhancers affect subcortical volumes in the adult human brain
Authors: Becker Martin , Guadalupe Tulio , Franke Barbara , Hibar Derrek P. , Renteria Miguel E. , Stein Jason L. , Thompson Paul M. , Francks Clyde , Vernes Sonja C. , Fisher Simon E. 
Published: February 2016

AbstractGenome‐wide association screens aim to identify common genetic variants contributing to the phenotypic variability of complex traits, such as human height or brain morphology. The identified genetic variants are mostly within noncoding genomic regions and the biology of the genotype–phenotype association typically remains unclear. In this article, we propose a complementary targeted strategy to reveal the genetic underpinnings of variability in subcortical brain volumes, by specifically selecting genomic loci that are experimentally validated forebrain enhancers, active in early embryonic development. We hypothesized that genetic variation within these enhancers may affect the development and ultimately the structure of subcortical brain regions in adults. We tested whether variants in forebrain enhancer regions showed an overall enrichment of association with volumetric variation in subcortical structures of >13,000 healthy adults. We observed significant enrichment of genomic loci that affect the volume of the hippocampus within forebrain enhancers (empirical P = 0.0015), a finding which robustly passed the adjusted threshold for testing of multiple brain phenotypes (cutoff of P < 0.0083 at an alpha of 0.05). In analyses of individual single nucleotide polymorphisms (SNPs), we identified an association upstream of the ID2 gene with rs7588305 and variation in hippocampal volume. This SNP‐based association survived multiple‐testing correction for the number of SNPs analyzed but not for the number of subcortical structures. Targeting known regulatory regions offers a way to understand the underlying biology that connects genotypes to phenotypes, particularly in the context of neuroimaging genetics. This biology‐driven approach generates testable hypotheses regarding the functional biology of identified associations. Hum Brain Mapp 37:1788–1800, 2016. © 2016 Wiley Periodicals, Inc.
Risk of swallowing‐related chest infections in patients with nasopharyngeal carcinoma treated with definitive intensity‐modulated radiotherapy
Authors: Xiong Jiaqing , Krishnaswamy Gita , Raynor Sharon , Loh Kwok Seng , Kwa Andrea Lay Hoon , Lim Chwee Ming 
Published: February 2016

AbstractBackgroundPulmonary complications secondary to dysphagia may be encountered in patients with nasopharyngeal carcinoma (NPC) after definitive intensity‐modulated radiotherapy. The purpose of this study was to identify patients with NPC at risk of developing swallowing‐related chest infections (SRCIs).MethodsRetrospective chart review was performed on 217 patients with stage I to IVB NPC treated definitively with radiotherapy or chemoradiotherapy.ResultsTwenty‐six patients (12.0%) developed SRCIs; 4 of these patients (15.3%) required intensive care unit (ICU) admission and 9 (34.6%) died of the complication. The median time interval between completions of radiotherapy to the development of SRCIs was 24.5 months. Advanced age, recurrent disease, and concurrent chemoradiotherapy were significantly associated with the development of SRCIs in the multivariable analysis.ConclusionSRCI is a common and potentially fatal complication for postirradiated patients with NPC. Advanced age, concurrent chemoradiotherapy, and recurrent cancer were strong risk factors for postirradiated patients with NPC to develop SRCIs. © 2016 Wiley Periodicals, Inc. Head Neck 38: E1660–E1665, 2016
Narrow band imaging for the diagnosis of head and neck squamous cell carcinoma: A systematic review
Authors: Cosway Benjamin , Drinnan Michael , Paleri Vinidh 
Published: February 2016

AbstractNarrow band imaging (NBI) is reported to improve the diagnostic accuracy of head and neck cancers. The purpose of this review was to evaluate the diagnostic accuracy of NBI in the literature. A systematic review was performed in PubMed, Web of Knowledge, and the Cochrane Library until March 2015. Two reviewers independently assessed articles and extracted data. Meta‐analyses were performed in MetaDisc 1.6. Five hundred seventeen studies were identified and 17 were included in this study. Combined use of NBI and white light imaging (WLI) showed high diagnostic accuracies for primary, recurrent, and nasopharyngeal lesions. Methodological heterogeneity exists and meta‐analyses were only appropriate for cancers of unknown primary (CUP) in which NBI performed on 115 patients across 4 studies demonstrated high sensitivity (74.1%; 95% confidence interval [CI] = 52.5% to 100%) and specificity (94.1%; 95% CI = 23.7% to 100%). NBI may further help identify lesions in CUP not seen by positron emission tomography (PET)‐CT. NBI offers a high level of diagnostic accuracy for head and neck cancers. © 2016 Wiley Periodicals, Inc. Head Neck 38: E2358–E2367, 2016
Cbfb2 Isoform Dominates More Potent Cbfb1 and Is Required for Skeletal Development
Authors: Jiang Qing , Qin Xin , Kawane Tetsuya , Komori Hisato , Matsuo Yuki , Taniuchi Ichiro , Ito Kosei , Izumi Shin-ichi , Komori Toshihisa 
Published: February 2016

ABSTRACT

Cbfb is a cotranscription factor that forms a heterodimer with Runx proteins Runx1, Runx2, and Runx3. It is required for fetal liver hematopoiesis and skeletal development. Cbfb has two functional isoforms, Cbfb1 and Cbfb2, which are formed by alternative splicing. To address the biological functions of these isoforms in skeletal development, we examined Cbfb1–/– and Cbfb2–/– mouse embryos. Intramembranous and endochondral ossification was retarded and chondrocyte and osteoblast differentiation was inhibited in Cbfb2–/– embryos but not in Cbfb1–/– embryos. Cbfb2 mRNA was upregulated in calvariae, limbs, livers, thymuses, and hearts of Cbfb1–/– embryos but Cbfb1 mRNA was not in those of Cbfb2–/– embryos, and the total amount of Cbfb1 and Cbfb2 mRNA in Cbfb1–/– embryos was similar to that in wild-type embryos but was severely reduced in Cbfb2–/– embryos. The absolute numbers of Cbfb2 mRNA in calvariae, limbs, livers, thymuses, and brains in wild-type embryos were about three times higher than those of Cbfb1 in the respective tissue. The levels of Runx proteins were reduced in calvariae, limbs, and primary osteoblasts from Cbfb2–/– embryos, but the reduction in Runx2 protein was very mild. Furthermore, the amounts of Runx proteins and Cbfb in Cbfb2–/– embryos differed similarly among skeletal tissues, livers, and thymuses, suggesting that Runx proteins and Cbfb are mutually required for their stability. Although Cbfb1–/– embryos developed normally, Cbfb1 induced chondrocyte and osteoblast differentiation and enhanced DNA binding of Runx2 more efficiently than Cbfb2. Our results indicate that modulations in the relative levels of the isoforms may adjust transcriptional activation by Runx2 to appropriate physiological levels. Cbfb2 was more abundant, but Cbfb1 was more potent for enhancing Runx2 activity. Although only Cbfb2 loss generated overt skeletal phenotypes, both may play major roles in skeletal development with functional redundancy. © 2016 American Society for Bone and Mineral Research.
Altered Hepatic Transport by Fetal Arsenite Exposure in Diet‐Induced Fatty Liver Disease
Authors: Ditzel Eric J. , Li Hui , Foy Caroline E. , Perrera Alec B. , Parker Patricia , Renquist Benjamin J. , Cherrington Nathan J. , Camenisch Todd D. 
Published: February 2016

ABSTRACTNon‐alcoholic fatty liver disease can result in changes to drug metabolism and disposition potentiating adverse drug reactions. Furthermore, arsenite exposure during development compounds the severity of diet‐induced fatty liver disease. This study examines the effects of arsenite potentiated diet‐induced fatty liver disease on hepatic transport in male mice. Changes were detected for Mrp2/3/4 hepatic transporter gene expression as well as for Oatp1a4/2b1/1b2. Plasma concentrations of Mrp and Oatp substrates were increased in arsenic exposure groups compared with diet‐only controls. In addition, murine embryonic hepatocytes and adult primary hepatocytes show significantly altered transporter expression after exposure to arsenite alone: a previously unreported phenomenon. These data indicate that developmental exposure to arsenite leads to changes in hepatic transport which could increase the risk for ADRs during fatty liver disease.
Ultrafiltration based purification strategies for surfactin produced by Bacillus subtilisLB5A using cassava wastewater as substrate
Authors: de Andrade Cristiano J , Barros Francisco FC , de Andrade Lidiane M , Rocco Silvana A , Luis Sforça Mauricio , Pastore Gláucia M , Jauregi Paula 
Published: February 2016

AbstractBACKGROUNDBacillus subtilis synthesizes surfactin, a powerful surface‐active agent. It has interesting potential applications. However, due to its high cost of production, commercial use is impracticable. The downstream processing represents ≈ 60% of production costs and the culture medium ≈ 30%. Many reports focused, separately, on production of surfactin using by‐products (reduced cost) or the purification using synthetic medium. Therefore, the aim of this work was to evaluate, for the first time, the impact of using a by‐product as fermentation medium on the downstream processing based on membrane filtration.RESULTSMembranes of PES‐100‐kDa efficiently retained surfactin micelles – the first step of ultrafiltration, whereas, the second step required membranes of 50 kDa to separate surfactin monomers from proteins. Ultrafiltration of crude biosurfactant was associated with fouling and/or concentration polarization resulting in lower purity than when synthetic medium was used. Further improvement in purity was achieved by partial removal of proteins before ultrafiltration by acid precipitation and extraction. The NMR and MALDI‐TOFMS analyses identified 11 potential surfactin homologues composed of two amino acid sequences.CONCLUSIONProduction of surfactin using cassava wastewater as a low‐cost culture medium and its purification by the 2‐step ultrafiltration process is feasible, nevertheless, the higher protein content of this medium compared with the synthetic one leads to a lower purity product; further increase in purity can be achieved by applying additional purification steps prior to ultrafiltration with subsequent increased process cost. © 2016 Society of Chemical Industry
Degradation of pollen on nanofunctionalized photocatalytic materials
Authors: Sapiña Maria , Jimenez‐Relinque Eva , Nevshupa Roman , Roman Elisa , Castellote Marta 
Published: February 2016

AbstractBACKGROUNDPhotocatalytic degradation of pollen components on titanium dioxide nanofunctionalized materials was studied for gymnosperm (Cupressus Arizonica) and angiosperm (Platanus Hybrida acerifolia).RESULTSScanning electron microscopy revealed structural degradation of both exine and intine strata. Fourier‐Transformed Infrared Spectroscopy was applied to characterize chemical modification of the pollen grains subjected to photocatalysis. Study of physical properties modification for the pollen extracts was carried out through spectrophotometry and wettability tests. It was found that photocatalysis resulted in significant decrease of C–H and C–O groups and a moderate decrease in C = O. Also, chromaticity values of the pollen extract after photocatalysis tended to approach those of the substrate. Contact angle of water dispersion of the pollen extract was not altered by photocatalysis, but adherence of the components of the pollen extract to Si substrate considerably decreased.CONCLUSIONSTaken together these results provided solid evidence for the degradation of all pollen components including exine and intine enzymes on nanofunctionalized photocatalytic materials. © 2016 Society of Chemical Industry