bluuebunny/crossref_metadata_2025 huggingface dataset:
Eine einfache und vielseitige dirigierende Amidgruppe zur Funktionalisierung von C‐H‐Bindungen
Authors: Zhu Ru‐Yi , Farmer Marcus E. , Chen Yan‐Qiao , Yu Jin‐Quan
Published: August 2016

Die selektive C‐H‐Aktivierung an einer einzigen und strategisch wichtigen Position in Gegenwart von zahlreichen weiteren C‐H‐Bindungen kann einen leistungsfähigen und allgemein nützlichen Schritt in der Syntheseplanung darstellen. In diesem Zusammenhang dient die dirigierende Gruppe als ein “Kompass”, um – mittels Abständen und Geometrien als Erkennungsparameter zur Unterscheidung zwischen proximalen und distalen C‐H‐Bindungen – das Übergangmetall an C‐H‐Bindungen zu lenken. Die Einführung und Abspaltung dirigierender Gruppen ist allerdings ein Nachteil für die Synthesepraxis. Um diese Ansätze nützlicher zu gestalten, kann man in drei Richtungen nach Lösungen suchen. Erstens, durch Vereinfachung der dirigierenden Gruppe; zweitens, durch Verwendung von gängigen funktionellen Gruppen oder Schutzgruppen als dirigierende Gruppen; drittens, durch Anbindung der dirigierenden Gruppe an Substrate über eine transiente kovalente Bindung, um die dirigierende Gruppe zu einem Katalysator zu machen. Dieser Aufsatz beschreibt die rationale Entwicklung einer sehr einfachen und dennoch breit anwendbaren dirigierenden Gruppe für PdII‐, RhIII‐ und RuII‐Katalysatoren, nämlich die N‐Methoxyamidgruppe (CONHOMe). Eine Vielzahl von Transformationen unter C‐H‐Aktivierung wurde mithilfe dieser einfachen dirigierenden Gruppen bereits entwickelt.
Organotin(IV) complexes derived from proteinogenic amino acid: synthesis, structure and evaluation of larvicidal efficacy on Anopheles stephensi mosquito larvae
Authors: Basu Baul Tushar S. , Kehie Pelesakuo , Höpfl Herbert , Duthie Andrew , Eng George , Linden Anthony
Published: August 2016

Five new organotin(IV) complexes of composition [Bz2SnL1]n (1), [Bz3SnL1H⋅H2O] (2), [Me2SnL2⋅H2O] (3), [Me2SnL3] (4) and [Bz3SnL3H]n (5) (where L1 = (2S)‐2‐{[(E)‐(4‐hydroxypentan‐2‐ylidene)]amino}‐4‐methylpentanoate, L2 = (rac)‐2‐{[(E)‐1‐(2‐hydroxyphenyl)methylidene]amino}‐4‐methylpentanoate and L3 = (2S)‐ or (rac)‐2‐{[(E)‐1‐(2‐hydroxyphenyl)ethylidene]amino}‐4‐methylpentanoate) were synthesized and characterized using 1H NMR, 13C NMR, 119Sn NMR and infrared spectroscopic techniques. The crystal structure of 2 reveals a distorted trigonal‐bipyramidal geometry around the tin atom where the oxygen atoms of the carboxylate ligand and a water ligand occupy the axial positions, while the three benzyl ligands are located at the equatorial positions. On the other hand, the analogous derivative of enantiopure L3H (5) consists of polymeric chains, in which the ligand‐bridged tin atoms adopt the same trans‐Bz3SnO2 trigonal‐bipyramidal configuration and are now coordinated to a phenolic oxygen atom instead of H2O. In 2, the OH hydrogen of the ketoimine substituent has moved to the nearby nitrogen atom while in the salicylidene derivative 5, the OH is located almost midway between the phenolic oxygen atom and the nitrogen atom of the CN group. For the dibenzyltin derivative 1, a polymeric chain structure is observed as a result of a long intermolecular Sn⋅⋅⋅O bond involving the exocyclic carbonyl oxygen atom from the tridentate ligand of a neighbouring tin‐complex unit. The tin atom in this complex has distorted octahedral coordination geometry. In contrast, the racemic dimethyltin(IV) complexes 3 and 4 display discrete monomeric structures with a distorted octahedral‐ and trigonal‐bipyramidal geometry, respectively. The structures show that the coordination mode of the Schiff base ligand depends primarily on the number of bulky benzyl ligands (R) at the tin atom, as indeed found in the structures of related complexes where R = phenyl. With three bulky R groups, the tridentate chelating O,N,O coordination mode is preferred, whereas with fewer or less bulky R ligands, only the carboxylate and hydroxy groups are involved, which leads to polymers. Larvicidal efficacies of two of the new tribenzyltin(IV) complexes (2 and 5) were assessed on the second larval instar of Anopheles stephensi mosquito larvae and compared with two triphenyltin(IV) analogues, [Ph3SnL1H]n and [Ph3SnL3H]n. The results demonstrate that the compounds containing Sn–Ph ligands are more effective than those with Sn–Bz ligands. Copyright © 2016 John Wiley & Sons, Ltd.
Evaluation of nanoemulsions based on silicone polyethers for demulsification of asphaltene model emulsions
Authors: da Fraga Assis Koppe , Oliveira Priscila F. , Oliveira Luis Fernando S. , Magalhães Jennifer , Mansur Claudia R. E.
Published: August 2016

Asphaltenes are considered the main agents responsible for stabilizing petroleum emulsions. However, due to the complex chemical nature of crude oil, it is necessary to extract these molecules and prepare model solutions to investigate the effects of the various asphaltenes separately. In this study, the demulsification efficiency of oil‐in‐water (O/W) nanoemulsions based on silicone polyethers was evaluated using asphaltene model emulsions. The interfacial properties of the model emulsions were evaluated, with and without the presence of the nanoemulsions, by interfacial tension and inerfacial rheology measurements and correlating them with the ability and/or speed of diffusion to the interface. Dispersion/flocculation tests of the asphaltenes were performed to assess whether the nanoemulsions were modifying the aggregation state of the asphaltenes during the process of destabilizing the model emulsions. Through the interfacial rheology tests of the model asphaltene/saltwater system, with or without addition of the systems used in the demulsification tests, it was possible to determine the influence of the nanoemulsions on the mechanical properties of the interfacial film. The results of the water/oil gravitational separation tests showed that the nanoemulsions had separation efficiency between 80 and 95%, depending on the composition of the water/surfactant/oil/asphaltene system. The nanoemulsions containing xylene as the oil phase destabilized the emulsions the fastest. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44174.
Synthesis and self‐assembly study of zwitterionic amphiphilic derivatives of chitosan
Authors: Franciane Gonçalves Barbosa Hellen , Margarete Furuyama Lima Aline , Roberto Taboga Sebastião , Cesar Fernandes Júlio , Aparecida de Oliveira Tiera Vera , José Tiera Marcio
Published: August 2016

New zwitterionic derivatives of chitosan (CH) were synthesized through the Michael addition reaction of 1‐(3‐sulfopropyl)‐2‐vinylpyridine hydroxide (SPP) with primary amines of deacetylated CHs (with weight‐average molecular weights of 46 and 216 kDa) to obtain SPP‐substituted CHs. The hydrophilic derivatives were subsequently modified with 2.1, 4.6, and 9.7% of dodecyl groups [degree of substitution by dodecyl groups (DSDod)]. The SPP‐substituted CH derivatives were characterized by 1H‐NMR, Fourier transform infrared spectroscopy, and gel permeation chromatography. Aqueous solutions of SPP‐substituted CH samples remained clear, independently of the pH (3.0 < pH < 12.0). The self‐association study of the amphiphilic derivatives was performed in aqueous buffered solution at pH 5.0 and 7.4, and the critical aggregation concentration values varied from 5.6 × 10−3 to 0.02 g/L. The measurements of dynamic light scattering and ζ potentials showed that the self‐assembly behavior was dependent on the pH and DSDod. At pH 7.4, the measured ζ potentials were near zero, and colloidal stability was provided by the hydrated zwitterionic shell of the aggregates. Transmission electron microscopy revealed spherelike microsized particles of broad distribution. The amphiphilic SPP‐substituted CH samples were shown to be nontoxic with a 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay performed with HeLa cells. The remarkable water solubility and nontoxicity displayed by the new SPP‐substituted CH derivatives showed promising properties for the design of CH‐based biomaterials and nanoparticles. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44176.
Assessment of efficiency and impacts of gillnets on fish conservation in a tropical freshwater fishery
Authors: Silvano Renato A.M. , Hallwass Gustavo , Juras Anastácio A. , Lopes Priscila F.M.
Published: August 2016

Gillnets are commonly used in tropical multi‐species fisheries and there is a need to investigate the comparative efficiency and impacts of this gear on fish populations and diversity. The efficiency and the impact of gillnets of distinct mesh sizes were compared in the Lower Tocantins River (Brazilian Amazon).

Fish sampling was conducted in 12 floodplain lakes using gillnets of distinct mesh sizes and 345 fish landings were recorded. Indicators of gillnet efficiency were: (1) catch per unit of effort (CPUE) of total fish sampled; (2) CPUE of fish caught by fishers; (3) CPUE of commercial fish sampled; and (4) proportion of biomass of commercial fish sampled. Indicators of impact were: (1) the number of non‐commercial fish (by‐catch); (2) the proportion of fish above the length at first maturity; (3) mean fish size (length); (4) total number of fish species and of rare fish species caught.

Gillnets of 8 cm mesh size showed a higher CPUE in fish samples and fish landings. This mesh size also showed reduced impacts (lower numbers of non‐commercial fish caught and higher proportion of adult fish).

Gillnets of 6 cm mesh size caught a smaller proportion of adult fish, smaller fish, more species and more rare species. Therefore, intensive use of these gillnets could increase the risk of regional species extinctions and impair the provision of ecosystem services by target fish.

Gillnets of 8 cm mesh size could improve fish catches while minimizing adverse effects of gillnet fishing. The practical management recommendation would be to replace the more damaging small mesh gillnets by gillnets with intermediate mesh size. This recommendation could simultaneously protect small‐sized rare species and larger fish, being broadly applicable to other small‐scale and multi‐species fisheries that use gillnets intensively in tropical countries with high fish diversity.

Copyright © 2016 John Wiley & Sons, Ltd.
The Reinforcing Value of Lottery Tickets, and the Synergetic Effect of Distinct Reinforcements
Authors: Luria Adi , Erev Ido , Haruvy Ernan
Published: August 2016

We present two experiments that explore the reinforcing value of lottery tickets. Participants are faced with a repeated choice task between a safe alternative and a risky prospect that provides a chance to win a lottery ticket to be played at the end of the study. Study 1 considers situations in which the risky option leads to a slightly higher expected value than the safe alternative. It shows that the risk‐taking rate increases with the probability to win the lottery ticket, but it is below 50% even when this probability is high. Study 2 shows limited sensitivity to the expected value of the risky prospect. The results can be explained with the assumption that participants rely on small samples of past experiences, and that their reaction to lottery tickets reflects large variability. The relationship between the current results and previous research on the synergetic effect of distinct reinforcements and the “pat on the back paradox” is discussed. Copyright © 2016 John Wiley & Sons, Ltd.
Diminishing return for mechanistic therapeutics with neurodegenerative disease duration?
Authors: Rubinsztein David C. , Orr Harry T.
Published: August 2016

The conventional approach to developing disease‐modifying treatments for neurodegenerative conditions has been to identify drivers of pathology and inhibit such pathways. Here we discuss the possibility that the efficacy of such approaches may be increasingly attenuated as disease progresses. This is based on experiments using mouse models of spinocerebellar ataxia type 1 and Huntington's disease (HD), where expression of the dominantly acting mutations could be switched off, as well as studies in human HD, which suggest that the primary genetic driver of age‐of‐onset of disease is a much weaker determinant of disease progression in affected individuals. The idea that one may approach a point in the disease course where such rational therapeutic strategies based on targets which determine onset of disease have minimal efficacy, suggests that one needs to consider other approaches to therapies and clinical trial design, including initiation of therapies in presymptomatic individuals.
A DIRECT ESTIMATION METHOD FOR THE RUSSELL FLUID FACTOR BASED ON STOCHASTIC SEISMIC INVERSION
Authors: Rui‐Ying SUN , Xing-Yao YIN , Bao-Li WANG , Guang-Zhi ZHANG
Published: August 2016

In this paper we propose Russell fluid factor direct estimation method based on stochastic seismic inversion. It is a Monte Carlo based strategy for non‐linear inversion, which can effectively integrate the high‐frequency information of well‐logging data and have a higher resolution. And the method is formulated in a Bayesian framework. Firstly, we can calculate the Russell fluid factor using well‐logging data and get the a priori information of fluid factor through sequential Gaussian simulation (SGS). Then we construct the likelihood function. Finally, we apply Metropolis algorithm in order to obtain an exhaustive description of the posteriori probability density. In this paper, we use the sequential Gaussian simulation (SGS) in a new implementation way, which can improve the computation speed. According to the numerical calculations, we can conclude that the final results match the model and real well‐logging data well and have a higher resolution. In addition, Russell fluid factor we inverted is a sensitive indicator for reservoir fluid identification.
Genomic characterization of response to chemoradiation in urothelial bladder cancer
Authors: Desai Neil B. , Scott Sasinya N. , Zabor Emily C. , Cha Eugene K. , Hreiki Joseph , Sfakianos John P. , Ramirez Ricardo , Bagrodia Aditya , Rosenberg Jonathan E. , Bajorin Dean F. , Berger Michael F. , Bochner Bernard H. , Zelefsky Michael J. , Kollmeier Marisa A. , Ostrovnaya Irina , Al‐Ahmadie Hikmat A. , Solit David B. , Iyer Gopa
Published: August 2016

BACKGROUND

The authors characterized the genetic landscape of chemoradiation‐treated urothelial carcinoma of the bladder (UCB) with the objective of identifying potential correlates of response.

METHODS

Primary tumors with (n = 8) or without (n = 40) matched recurrent tumors from 48 patients who had non‐metastatic, high‐grade UCB and received treatment primarily with chemoradiation were analyzed using a next‐generation sequencing assay enriched for cancer‐related and canonical DNA damage response (DDR) genes. Protein expression of meiotic recombination 11 homolog (MRE11), a previously suggested biomarker, was assessed in 44 patients. Recurrent tumors were compared with primary tumors, and the clinical impact of likely deleterious DDR gene alterations was evaluated.

RESULTS

The profile of alterations approximated that of prior UCB cohorts. Within 5 pairs of matched primary‐recurrent tumors, a median of 92% of somatic mutations were shared. A median 33% of mutations were shared between 3 matched bladder‐metastasis pairs. Of 26 patients (54%) who had DDR gene alterations, 12 (25%) harbored likely deleterious alterations. In multivariable analysis, these patients displayed a trend toward reduced bladder recurrence (hazard ratio, 0.32; P = .070) or any recurrence (hazard ratio, 0.37; P = .070). The most common of these alterations, ERCC2 (excision repair cross‐complementation group 2) mutations, were associated with significantly lower 2‐year metastatic recurrence (0% vs 43%; log‐rank P = .044). No impact of MRE11 protein expression on outcome was detected.

CONCLUSIONS

A similar mutation profile between primary and recurrent tumors suggests that pre‐existing, resistant clonal populations represent the primary mechanism of chemoradiation treatment failure. Deleterious DDR genetic alterations, particularly recurrent alterations in ERCC2, may be associated with improved chemoradiation outcomes in patients with UCB. A small sample size necessitates independent validation of these observations. Cancer 2016;122:3715‐23. © 2016 American Cancer Society.
Hyper‐CVAD plus ponatinib versus hyper‐CVAD plus dasatinib as frontline therapy for patients with Philadelphia chromosome‐positive acute lymphoblastic leukemia: A propensity score analysis
Authors: Sasaki Koji , Jabbour Elias J. , Ravandi Farhad , Short Nicholas J. , Thomas Deborah A. , Garcia‐Manero Guillermo , Daver Naval G. , Kadia Tapan M. , Konopleva Marina Y. , Jain Nitin , Issa Ghayas C. , Jeanis Vicki , Moore Haim G. , Garris Rebecca S. , Pemmaraju Naveen , Cortes Jorge E. , O'Brien Susan M. , Kantarjian Hagop M.
Published: August 2016

BACKGROUND

The clinical efficacy of hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (HCVAD) plus ponatinib has not been compared with that of HCVAD plus dasatinib in patients with Philadelphia chromosome‐positive acute lymphoblastic leukemia (Ph+ ALL) in a randomized clinical trial.

METHODS

The authors analyzed 110 patients with newly diagnosed Ph+ ALL who were enrolled in 2 consecutive, prospective, phase 2 clinical trials of frontline HCVAD with either dasatinib (63 patients) or ponatinib (47 patients). Propensity score analysis with 1:1 matching with the nearest neighbor matching method and inverse probability of treatment weighting (IPTW) analysis based on the propensity scores were performed to assess response rates, event‐free survival (EFS), and overall survival (OS) between the cohorts.

RESULTS

Propensity score matching identified 41 patients in each cohort. With propensity score matching, the 3‐year EFS rates for patients treated with HCVAD plus ponatinib and HCVAD plus dasatinib were 69% and 46%, respectively (P =.04), and the 3‐year OS rates were 83% and 56%, respectively (P =.03). IPTW analysis using prematching cohorts demonstrated that patients treated with HCVAD plus ponatinib had significantly higher rates of minimal residual disease negativity by flow cytometry on day 21, complete cytogenetic response at complete response, major molecular response at complete response and at 3 months, and complete molecular response at 3 months. IPTW confirmed that treatment with HCVAD plus ponatinib was associated with longer EFS (P =.003) and OS (P =.001) compared with treatment with HCVAD plus dasatinib.

CONCLUSIONS

The clinical outcome of patients treated with HCVAD plus ponatinib appears to be superior to that of patients treated with HCVAD plus dasatinib among individuals with Ph+ ALL. Cancer 2016;122:3650‐6. © 2016 American Cancer Society.
Immunoblotting and Immunodetection
Authors: Ni Duojiao , Xu Peng , Gallagher Sean
Published: August 2016

Immunoblotting (western blotting) is used to identify specific antigens recognized by polyclonal or monoclonal antibodies. This unit provides protocols for all steps, starting with solubilization of the protein samples, usually by means of SDS and reducing agents. Following solubilization, the material is separated by SDS‐PAGE and the antigens are electrophoretically transferred to a membrane, a process that can be monitored by reversible staining with Ponceau S. The transferred proteins are bound to the surface of the membrane, providing access to immunodetection reagents. After nonspecific binding sites are blocked, the membrane is probed with the primary antibody and washed. The antibody‐antigen complexes are tagged with fluorophores, horseradish peroxidase, or alkaline phosphatase coupled to a secondary anti‐IgG antibody, and detected using appropriate fluorescent imaging technologies or with chromogenic or luminescent substrates. Finally, membranes may be stripped and reprobed. © 2016 by John Wiley & Sons, Inc.
Solid Solution Photocatalyst with Spontaneous Polarization Exhibiting Low Recombination Toward Efficient CO2 Photoreduction
Authors: Zhou Peng , Wang Xin , Yan Shicheng , Zou Zhigang
Published: August 2016

Decreasing the recombination of photogenerated carriers is a major challenge for efficiently converting solar energy into chemical energy by photocatalysis. Here, we have demonstrated that growth of a polar GaN:ZnO solid solution single crystal along its polarization axis is beneficial to efficient separation of photogenerated carriers, owing to the periodic potential barriers and wells generated from the periodically positive and negative atom arrangements in crystal structure. Local charge imbalance caused by replacing Ga3+ with Zn2+ leads to a polarization vector in the {0 0 0 1} planes of GaN:ZnO solid solution, thus forming a 1 D electron transport path along [2 
 
 0] in the {0 0 0 1} planes of GaN:ZnO solid solution to decrease recombination. Shorting the hole‐transport distance by synthesizing porous nanoplates can further decrease recombination under the polarization field and improve the performance of polar photocatalyst in photoreduction of CO2 into CH4.
Total belowground carbon flux in subalpine forests is related to leaf area index, soil nitrogen, and tree height
Authors: Berryman E. , Ryan M. G. , Bradford J. B. , Hawbaker T. J. , Birdsey R.
Published: August 2016

In forests, total belowground carbon (C) flux (TBCF) is a large component of the C budget and represents a critical pathway for delivery of plant C to soil. Reducing uncertainty around regional estimates of forest C cycling may be aided by incorporating knowledge of controls over soil respiration and TBCF. Photosynthesis, and presumably TBCF, declines with advancing tree size and age, and photosynthesis increases yet C partitioning to TBCF decreases in response to high soil fertility. We hypothesized that these causal relationships would result in predictable patterns of TBCF, and partitioning of C to TBCF, with natural variability in leaf area index (LAI), soil nitrogen (N), and tree height in subalpine forests in the Rocky Mountains, USA. Using three consecutive years of soil respiration data collected from 22 0.38‐ha locations across three 1‐km2 subalpine forested landscapes, we tested three hypotheses: (1) annual soil respiration and TBCF will show a hump‐shaped relationship with LAI; (2) variability in TBCF unexplained by LAI will be related to soil nitrogen (N); and (3) partitioning of C to TBCF (relative to woody growth) will decline with increasing soil N and tree height. We found partial support for Hypothesis 1 and full support for Hypotheses 2 and 3. TBCF, but not soil respiration, was explained by LAI and soil N patterns (r2 = 0.49), and the ratio of annual TBCF to TBCF plus aboveground net primary productivity (ANPP) was related to soil N and tree height (r2 = 0.72). Thus, forest C partitioning to TBCF can vary even within the same forest type and region, and approaches that assume a constant fraction of TBCF relative to ANPP may be missing some of this variability. These relationships can aid with estimates of forest soil respiration and TBCF across landscapes, using spatially explicit forest data such as national inventories or remotely sensed data products.
Virgin olive oil yield as affected by physicochemical talc properties and dosage
Authors: Sadkaoui Abir , Jiménez Antonio , Aguilera Maria P. , Pacheco Rafael , Beltrán Gabriel
Published: August 2016

The aim of this work was to assess the effect of physicochemical characteristics of micronized natural talc (MNT) and its dosage on the industrial oil yield (IY) during virgin olive oil (VOO) extraction of Hojiblanca fruits. For this purpose, laboratory scale experiments were performed testing four commercial MNTs differing in their particle size (D50) and carbonate rate at doses ranging from 0 to 3%. The most efficient MNT was characterized by the highest carbonate rate and the lowest particle size achieving the highest improvement of the IY for a dose of 2%. It was also found that the effect of particles size and carbonate rate depends on the MNT dose, being much more pronounced at lower doses and that the use of MNTs with low carbonate levels or high particle size could be compensated using higher doses of talc.

Practical applications: This study provides deeper insights into the clarification of the effect of the addition of different doses of MNT, with different physicochemical characteristics on oil yield of Hojiblanca olive fruits. The information contained in this study should be taken into account to choose the suitable MNT dose considering its physicochemical characteristics in order to improve the oil yield for the so‐called difficult pastes.

Physical and chemical characteristics of talc affect VOO yield.
Flavonoids in Selected Mediterranean Fruits: Extraction, Electrochemical Detection and Total Antioxidant Capacity Evaluation
Authors: Issaad Fatima Zohra , Fernandes Isabel P. G. , Enache Teodor A. , Mouats Chabane , Rodrigues Isaide A. , Oliveira‐Brett Ana Maria
Published: August 2016

Flavonoids are natural phenolic derivatives that, in low concentration, can provide health benefits by preventing biomolecules (proteins, nucleic acids, lipids, sugars) oxidative damage through free radical mediated reactions. The flavonoids, in selected Mediterranean seasonal fruits: apricot, sour cherry, plum, pomegranate, date, prickly pear (cactus fruit), and nectarine, by RP‐HPLC, coupled with photodiode array and electrochemical detectors, after microwave‐ultrasound assisted extraction, using flavonoid standards, were detected. The total antioxidant capacity in the lyophilized fruit extracts, by differential pulse voltammetry, (electrochemical index‐EI), integrated peak area, and chronoamperometry, was evaluated. In the lyophilized fruit extracts, and the catechin standard, the free radical scavenger efficient concentration (EC50), using DPPH. assay, was determined.
Effect of electrode surface properties on enhanced electron transfer activity in microbial fuel cells
Authors: Choudhury Abhinav , Barbora Lepakshi , Arya Divyanshu , Lal Banwari , Subudhi Sanjukta , Mohan S. Venkata , Ahammad Shaikh Z. , Verma Anil
Published: August 2016

The influence of electrode surface chemistry over biofilm growth was evaluated for photo‐bioelectrocatalytic fuel cell. A consortium of photosynthetic bacteria was grown onto different electrodes designed with polyethylenimine (PEI) and multiwall carbon nanotubes as hydrophilic and hydrophobic modifier, respectively. The designed electrodes were loaded with 0.08, 0.17, and 0.33 μg/cm2 of PEI to change the hydrophilicity. However, 0.56, 0.72, and 0.83 mg/cm2 of multiwall carbon nanotubes were used to alter the hydrophobicity of the electrodes. The surface chemistry of electrode and bio‐interaction was evaluated as a function of contact angle and biofilm formation. The results were compared with those obtained with a carbon paper electrode. The contact angle on the untreated electrode (carbon paper) was 118°, whereas for hydrophobic and hydrophilic electrodes, the maximum and minimum contact angles were 170° and 0°, respectively. Interestingly, the maximum biofilm growth (0.2275 g, wet basis) was observed on highly hydrophobic surface; however, the maximum electrochemical performance (246 mV) was shown by the most hydrophilic electrode surface. PEI‐based electrode with good biofilm formation showed comparatively higher electrogenic activity.
Insight into sediment transport processes on saline rangeland hillslopes using three‐dimensional soil microtopography changes
Authors: Nouwakpo Sayjro K. , Weltz Mark A. , McGwire Kenneth C. , Williams Jason C. , Osama Al‐Hamdan , Green Colleen H.M.
Published: August 2016

In arid and semi‐arid rangeland environments, an accurate understanding of runoff generation and sediment transport processes is key to developing effective management actions and addressing ecosystem response to changes. Yet, many primary processes (namely sheet and splash and concentrated flow erosion, as well as deposition) are still poorly understood due to a historic lack of measurement techniques capable of parsing total soil loss into these primary processes. Current knowledge gaps can be addressed by combining traditional erosion and runoff measurement techniques with image‐based three‐dimensional (3D) soil surface reconstructions. In this study, data (hydrology, erosion and high‐resolution surface microtopography changes) from rainfall simulation experiments on 24 plots in saline rangelands communities of the Upper Colorado River Basin were used to improve understanding on various sediment transport processes. A series of surface change metrics were developed to quantify and characterize various erosion and transport processes (e.g. plot‐wide versus concentrated flow detachment and deposition) and were related to hydrology and biotic and abiotic land surface characteristics. In general, erosivity controlled detachment and transport processes while factors modulating surface roughness such as vegetation controlled deposition. The extent of the channel network was a positive function of slope, discharge and vegetation. Vegetation may deflect runoff in many flow paths but promoted deposition. From a management perspective, this study suggests that effective runoff soil and salt load reduction strategies should aim to promote deposition of transported sediments rather than reducing detachment which might not be feasible in these resource‐limited environments. Copyright © 2016 John Wiley & Sons, Ltd.
Blind channel estimation for FBMC‐based PMR transmission
Authors: Terré M. , Féty L. , Ahriz I. , Maoudj R. , Martinod L. , Mege P.
Published: August 2016

The paper presents a blind channel estimation algorithm for an filter bank multicarriers waveform in a fast varying channel context for professional mobile radio transmissions. A fourth‐order power elevation algorithm, followed by an auto‐deconvolution step, directly leading to the channel impulse response estimation, is developed. Simulation results are adapted to the Tetra enhanced data services standard context for hilly terrain propagation model. Copyright © 2016 John Wiley & Sons, Ltd.
TGFβ regulates persistent neuroinflammation by controlling Th1 polarization and ROS production via monocyte‐derived dendritic cells
Authors: Parsa Roham , Lund Harald , Tosevski Ivana , Zhang Xing‐Mei , Malipiero Ursula , Beckervordersandforth Jan , Merkler Doron , Prinz Marco , Gyllenberg Alexandra , James Tojo , Warnecke Andreas , Hillert Jan , Alfredsson Lars , Kockum Ingrid , Olsson Tomas , Fontana Adriano , Suter Tobias , Harris Robert A.
Published: August 2016

Intracerebral levels of Transforming Growth Factor beta (TGFβ) rise rapidly during the onset of experimental autoimmune encephalomyelitis (EAE), a mouse model of Multiple Sclerosis (MS). We addressed the role of TGFβ responsiveness in EAE by targeting the TGFβ receptor in myeloid cells, determining that Tgfbr2 was specifically targeted in monocyte‐derived dendritic cells (moDCs) but not in CNS resident microglia by using bone‐marrow chimeric mice. TGFβ responsiveness in moDCs was necessary for the remission phase since LysMCreTgfbr2fl/fl mice developed a chronic form of EAE characterized by severe demyelination and extensive infiltration of activated moDCs in the CNS. Tgfbr2 deficiency resulted in increased moDC IL‐12 secretion that skewed T cells to produce IFN‐γ, which in turn enhanced the production of moDC‐derived reactive oxygen species that promote oxidative damage and demyelination. We identified SNPs in the human NOX2 (CYBB) gene that associated with the severity of MS, and significantly increased CYBB expression was recorded in PBMCs from both MS patients and from MS severity risk allele rs72619425‐A carrying individuals. We thus identify a novel myeloid cell‐T cell activation loop active in the CNS during chronic disease that could be therapeutically targeted. GLIA 2016;64:1925–1937
The system neurophysiological basis of non‐adaptive cognitive control: Inhibition of implicit learning mediated by right prefrontal regions
Authors: Stock Ann‐Kathrin , Steenbergen Laura , Colzato Lorenza , Beste Christian
Published: August 2016

Cognitive control is adaptive in the sense that it inhibits automatic processes to optimize goal‐directed behavior, but high levels of control may also have detrimental effects in case they suppress beneficial automatisms. Until now, the system neurophysiological mechanisms and functional neuroanatomy underlying these adverse effects of cognitive control have remained elusive. This question was examined by analyzing the automatic exploitation of a beneficial implicit predictive feature under conditions of high versus low cognitive control demands, combining event‐related potentials (ERPs) and source localization. It was found that cognitive control prohibits the beneficial automatic exploitation of additional implicit information when task demands are high. Bottom‐up perceptual and attentional selection processes (P1 and N1 ERPs) are not modulated by this, but the automatic exploitation of beneficial predictive information in case of low cognitive control demands was associated with larger response‐locked P3 amplitudes and stronger activation of the right inferior frontal gyrus (rIFG, BA47). This suggests that the rIFG plays a key role in the detection of relevant task cues, the exploitation of alternative task sets, and the automatic (bottom‐up) implementation and reprogramming of action plans. Moreover, N450 amplitudes were larger under high cognitive control demands, which was associated with activity differences in the right medial frontal gyrus (BA9). This most likely reflects a stronger exploitation of explicit task sets which hinders the exploration of the implicit beneficial information in case of high cognitive control demands. Hum Brain Mapp 37:4511–4522, 2016. © 2016 Wiley Periodicals, Inc.
δ15N from soil to wine in bulk samples and proline
Authors: Paolini Mauro , Ziller Luca , Bertoldi Daniela , Bontempo Luana , Larcher Roberto , Nicolini Giorgio , Camin Federica
Published: August 2016

The feasibility of using δ15N as an additional isotopic marker able to link wine to its area of origin was investigated. The whole production chain (soil–leaves–grape–wine) was considered. Moreover, the research included evaluation of the effect of the fermentation process, the use of different types of yeast and white and red vinification, the addition of nitrogen adjuvants and ultrasound lysis simulating wine ageing. The δ15N of grapes and wine was measured in bulk samples and compounds, specifically in proline, for the first time.

Despite isotopic fractionation from soil to wine, the δ15N values of leaves, grapes, wine and particularly must and wine proline conserved the variability of δ15N in the growing soil. Fermentation and ultrasound treatment did not affect the δ15N values of grape must, which was therefore conserved in wine. The addition of inorganic or organic adjuvants was able to influence the δ15N of bulk wine, depending on the amount and the difference between the δ15N of must and that of the adjuvant. The δ15N of wine proline was not influenced by adjuvant addition and is therefore the best marker for tracing the geographical origin of wine. Copyright © 2016 John Wiley & Sons, Ltd.
Climatology of cold season lake‐effect cloud bands for the North American Great Lakes
Authors: Laird Neil F. , Metz Nicholas D. , Gaudet Lauriana , Grasmick Coltin , Higgins Lindsey , Loeser Carlee , Zelinsky David A.
Published: August 2016

Geostationary Operational Environmental Satellite (GOES) visible imagery was used to identify lake‐effect (LE) clouds in the North American Great Lakes region for the cold seasons (October–March) of 1997/1998 through 2013/2014 to provide a comprehensive climatological description of the seasonal and interannual variability of LE cloud bands. During the average cold season, at least 60% of days each month had LE clouds over some portion of the Great Lakes region and nearly 75% of all LE days had LE clouds present over several lakes simultaneously. Wind‐parallel bands (WPB) are observed far more frequently than any other type of LE over Lakes Superior, Michigan, and Huron during the months of December, January, and February. Over Lake Erie, the occurrence of days per month with WPB was found to be approximately 5–10% greater than days with shore‐parallel bands (SPBs) throughout the entire cold season. The greatest frequency of SPB occurrences in the Great Lakes region was over Lake Ontario during the months of January and February (∼20% of days). In addition, Lake Ontario was the only lake where the frequencies of WPB and SPB occurrences were fairly similar each month. The annual frequency of WPB occurrences are the most variable among the Great Lakes, decreasing in frequency from the western lakes toward the eastern lakes. Lake Ontario has the largest annual frequency of SPB occurrences and the greatest variation in SPB annual frequency. Lake Huron has the second largest annual frequency of SPB days with small interannual variation. The primary differences of the annual frequency of lake‐to‐lake (L2L) LE occurrences when compared with previous research were a greater variability in the L2L annual frequency of Superior‐to‐Michigan connections, greater frequency of Michigan‐to‐Huron connections, and less frequent occurrences for Superior‐to‐Huron and Michigan‐to‐Erie connections.
Surface‐enhanced Raman scattering properties of Lewis acid–base complexes ofp‐hydroxybenzoic andp‐mercaptobenzoic acids with CO2in the presence of silver
Authors: Filho Manoel A. M. , Cunha Silvio , Rivelino Roberto
Published: August 2016

Effects of local environment on the sensitivity of surface‐enhanced Raman scattering have been recently considered as an important issue in experiments involving charge‐transfer mechanism between the adsorbed molecules and the metal surface. To theoretically investigate this issue, we consider the complexation ofp‐hydroxybenzoic acid (PHBA) andp‐mercaptobenzoic acid (PMBA) with carbon dioxide (CO2), and in contact with silver (Ag), by means of ab initio calculations. Within the Møller–Plesset perturbation theory, it is demonstrated that the carboxylic group of PHBA or PMBA can act as an electron‐donating site, binding the electron‐deficient carbon atom of CO2, via a Lewis acid–base (LA–LB) interaction. Changes in the vibrational spectra of these molecules are carefully determined and attributed to both LA–LB complexation with CO2and interaction with Ag. Calculated Raman scattering shifts for the complexes also indicate that the chemical nature of the substituent group atparaposition of the aromatic ring can dramatically alter the signal of typical shifts expected for LA–LB complexes, as well as affect surface‐enhanced Raman scattering intensities. The LA–LB complexation is also reinforced by the ultraviolet–visible absorption spectra for the complexes, calculated within time‐dependent density functional theory and combined with the polarizable continuum model, employed to simulate the local environment dielectric constant. It is demonstrated that the lowest singletπ–π* excitation of both LA–LB complexes, PHBA and PMBA weakly bound to CO2, is significantly red shifted, which gives evidence for such a complexation. Copyright © 2016 John Wiley & Sons, Ltd.
Azido Platform Surfaces for Post‐Functionalization with Aromatic Groups Using the Huisgen Reaction to Obtain High Water Adhesion
Authors: Godeau Guilhem , N'Na Jessica , Guittard Frédéric , Darmanin Thierry
Published: August 2016

In this work, platform post‐modifications using the Huisgen reaction are reported. Various platform surfaces are developed and post‐functionalized with aryl side chains. The development of different conducting polymer platforms allows the study of the impact of the starting surface on the modified surface properties. Also in this work, different aryl side chains are investigated (with one, two, three, or four aromatic rings) in order to investigate the impact of the side chain on the final surface feature. All the combinations (surface vs aryl side chain) are investigated for their wettability. Highly hydrophobic features are observed with apparent contact angles θ higher than 140° and extremely high water adhesion. Surface morphologies are also investigated and important changes in morphology are observed after surface post‐functionalization. The reported strategy to develop various highly hydrophobic surfaces with high water adhesion feature can be a powerful strategy for water trap elaboration.

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Bioinspired Polarization Sensitive Photodetector System Using Orientation‐Tunable PDA Microfibers Arrays
Authors: Liu Yingying , Xia Hongyan , Cheng Junjie , Zou Gang
Published: August 2016

Most insect eyes use microvillar photoreceptors, where the visual pigment rhodopsin is aligned within tubular microvilli, endowing the insects with amazing navigation ability through detecting the polarization of illuminating light in the sky. Herein, polydiacetylene‐polystyrene (PDA‐PS) hybrid microfibers are fabricated by electrospinning method and it is demonstrated that PDA‐PS hybrid microfibers exhibit interesting polarized waveguiding properties, which is found to be dependent on the ordered alignment of PDA chains, but not on the propagating distance or the wavelength of the excitation light. Moreover, three PDA‐PS microfibers with different polarized waveguiding behavior can be assembled together as polarization sensitive photoreceptors to mimic the natural rhabdome arrays in insect eyes, since the physical dimensions, structure, and function of single PDA‐PS microfiber are comparable to that of natural rhabdomere.

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Click Crosslinked Chitosan/Gold Nanocomposite Hydrogels
Authors: García‐Astrain Clara , Hernández Rebeca , Guaresti Olatz , Fruk Ljiljana , Mijangos Carmen , Eceiza Arantxa , Gabilondo Nagore
Published: August 2016

Preparation of novel nanocomposite hydrogels opens up new avenues to next generation of biocompatible materials to be used in bioengineering and drug delivery. Toward this goal, chitosan nanocomposite hydrogels using click chemistry inspired cross‐linking are prepared. To enable this, Diels–Alder reaction of furan‐containing chitosan and maleimide‐coated gold nanoparticles is employed. The viscoelastic properties of the obtained nanocomposites as well as the effect of the nanoparticles as cross‐linkers are studied, indicating that they play significant role in hydrogel formation and stability. Nanoparticle‐enriched hydrogels are also found to demonstrate pH‐sensitivity therefore showing their potential for future biosensing applications.

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Comparison of biomarker expression between proximal and distal colorectal adenomas: The Tennessee–Indiana Adenoma Recurrence Study
Authors: Su Timothy , Washington M. Kay , Ness Reid M. , Rex Douglas K. , Smalley Walter E. , Ulbright Thomas M. , Cai Qiuyin , Zheng Wei , Shrubsole Martha J.
Published: August 2016

It is unclear if proximal and distal traditional adenomas present with differences in molecular events which contribute to cancer heterogeneity by tumor anatomical subsite. Participants from a colonoscopy‐based study (n = 380) were divided into subgroups based on the location of their most advanced adenoma: proximal, distal, or “equivalent both sides.” Eight biomarkers in the most advanced adenomas were evaluated by immunohistochemistry (Ki‐67, COX‐2, TGFβRII, EGFR, β‐catenin, cyclin D1, c‐Myc) or TUNEL (apoptosis). After an adjustment for pathological features, there were no significant differences between proximal and distal adenomas for any biomarker. Conversely, expression levels did vary by other features, such as their size, villous component, and synchronousness. Large adenomas had higher expression levels of Ki‐67(P < 0.001), TGFβRII (P < 0.0001), c‐Myc (P < 0.001), and cyclin D1 (P < 0.001) in comparison to small adenomas, and tubulovillous/villous adenomas also were more likely to have similar higher expression levels in comparison to tubular adenomas. Adenoma location is not a major determinant of the expression of these biomarkers outside of other pathological features. This study suggests similarly important roles of Wnt/β‐catenin and TGF‐β pathways in carcinogenesis in both the proximal and distal colorectum. © 2016 Wiley Periodicals, Inc.
Effect of injection rate on contrast‐enhanced MR angiography image quality: Modulation transfer function analysis
Authors: Clark Toshimasa J. , Wilson Gregory J. , Maki Jeffrey H.
Published: August 2016

Purpose

Contrast‐enhanced (CE)‐MRA optimization involves interactions of sequence duration, bolus timing, contrast recirculation, and both R1 relaxivity and
‐related reduction of signal. Prior data suggest superior image quality with slower gadolinium injection rates than typically used.

Methods

A computer‐based model of CE‐MRA was developed, with contrast injection, physiologic, and image acquisition parameters varied over a wide gamut. Gadolinium concentration was derived using Verhoeven's model with recirculation, R1 and
calculated at each time point, and modulation transfer curves used to determine injection rates, resulting in optimal resolution and image contrast for renal and carotid artery CE‐MRA. Validation was via a vessel stenosis phantom and example patients who underwent carotid CE‐MRA with low effective injection rates.

Results

Optimal resolution for renal and carotid CE‐MRA is achieved with injection rates between 0.5 to 0.9 mL/s and 0.2 to 0.3 mL/s, respectively, dependent on contrast volume. Optimal image contrast requires slightly faster injection rates. Expected signal‐to‐noise ratio varies with both contrast volume and cardiac output. Simulated vessel phantom and clinical carotid CE‐MRA exams at an effective contrast injection rate of 0.4 to 0.5 mL/s demonstrate increased resolution.

Conclusion

Optimal image resolution is achieved at intuitively low, effective injection rates (0.2–0.9 mL/s, dependent on imaging parameters and contrast injection volume). Magn Reson Med 78:357–369, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Proteomic profiling of Gram‐negative bacterial outer membrane vesicles: Current perspectives
Authors: Lee Jaewook , Kim Oh Youn , Gho Yong Song
Published: August 2016

Outer membrane vesicles (OMVs) are extracellular vesicles derived from Gram‐negative bacteria. Recent progress in the studies of Gram‐negative bacterial extracellular vesicles implies that OMVs may function as intercellular communicasomes in bacteria–bacteria and bacteria–host interactions. Current MS‐based high‐throughput proteomic analyses of Gram‐negative bacterial OMVs have identified thousands of vesicular proteins and provided clues to reveal the biogenesis and pathophysiological functions of Gram‐negative bacterial OMVs. The future directions of proteomics of Gram‐negative bacterial OMVs may include the isolation strategy of Gram‐negative bacterial OMVs to thoroughly exclude nonvesicular contaminants and proteomics of Gram‐negative bacterial OMVs derived from diverse conditions as well as body fluids of bacterium‐infected hosts. We hope this review will shed light on future research in this emerging field of proteomics of extracellular vesicles derived from Gram‐negative bacteria and contribute to the development of OMV‐based diagnostic tools and effective vaccines.