bluuebunny/crossref_metadata_2025 huggingface dataset:
Ce1−xCrxO2−δ Nanocrystals as Efficient Catalysts for the Selective Oxidation of Cyclohexane to KA Oil at Low Temperature under Ambient Pressure
Authors: Huang Xiubing , Zhao Guixia , Wang Peng , Zheng Haiyan , Dong Wenjun , Wang Ge
Published: November 2017

The selective oxidation of C−H bonds in saturated hydrocarbons at low temperature with noble‐metal‐free heterogeneous catalysts is a profound challenge for the catalysis community. Here we report the facile synthesis of Ce1−xCrxO2−δ (x=0, 0.1, 0.2, 0.3, and 0.4) nanocrystals through a low‐temperature hydrothermal method. The catalytic activity of the as‐prepared catalysts was evaluated in the selective oxidation of cyclohexane to cyclohexanone/cyclohexanol using H2O2 as an oxidant at room temperature and 45 °C. The activity results were correlated with their phase structure, composition, surface areas, and surface element states with the help of X‐ray diffraction, N2 adsorption, transmission electron microscopy, X‐ray photoelectron spectroscopy, and UV/Vis spectroscopy. It was found that these Ce0.7Cr0.3O2−δ nanocrystals are highly active for the selective oxidation of cyclohexane to cyclohexanone/cyclohexanol using H2O2 as an oxidant at low temperature. In the presence of H2O2 at 45 °C for 5 h using Ce0.7Cr0.3O2−δ as a catalyst, the conversion of cyclohexane reaches 50.3 % and the total selectivity of cyclohexanol/cyclohexanone is 94.4 % with relative good reversibility for at least four cycles. Mechanistic investigation results show that the high activity can be attributed to the high Cr6+ content in the Ce1−xCrxO2−δ solid solutions and the formation of highly oxidative intermediates with H2O2.
Platinum–Copper Rhombic Dodecahedral Nanoframes with Tunable Channels as Efficient Bifunctional Electrocatalysts for Fuel‐Cell Reactions
Authors: Sun Xiuhui , Huang Bin , Cui Xiaoneng , E Bin , Feng Yonggang , Huang Xiaoqing
Published: November 2017

Three‐dimensional (3 D) nanoframes (NFs) with interconnected edges and large surface areas represent a new class of nanostructures with advanced catalytic performance. Herein, we report an efficient chemical strategy for the controlled synthesis of platinum–copper (Pt–Cu) rhombic dodecahedral nanocrystals (RDH NCs) with highly composition‐segregated features. These solid Pt–Cu RDH NCs could be readily transformed into highly open Pt–Cu RDH nanoframes (NFs) with shapes and sizes that were not markedly changed after FeCl3 etching. All of the different Pt–Cu RDH NFs have the same PtCu3 phase but tunable sizes and different channel sizes. These important characteristics of the NFs provide them with much better performance than that observed for commercial Pt/C and Pt–Cu RDH NCs towards both the oxygen reduction reaction (ORR) and the methanol oxidation reaction (MOR). In particular, PtCu5 RDH NFs with the largest channel size of all the samples investigated exhibited the best activity towards the ORR and MOR and showed much less activity decay after durability tests. This work highlights the importance of precise control of 3 D NF structures in enhancing electrocatalysis electrooxidations.
Surface Fluorination to Boost the Stability of the Fe/N/C Cathode in Proton Exchange Membrane Fuel Cells
Authors: Wang Yu‐Cheng , Zhu Peng‐Fei , Yang Hong , Huang Long , Wu Qi‐Hui , Rauf Muhammad , Zhang Jun‐Yu , Dong Jiao , Wang Kun , Zhou Zhi‐You , Sun Shi‐Gang
Published: November 2017

The ternary Fe/N/C material is a promising non‐precious‐metal oxygen reduction electrocatalyst for proton exchange membrane cells (PEMFCs). However, its practical application is severely hampered by poor stability under PEMFC working conditions, especially at a cell voltage higher than 0.5 V. Herein, we report a new strategy to significantly improve the stability of the Fe/N/C catalyst in PEMFCs by covalent grafting of a trifluoromethylphenyl (Ar‐CF3) group. The hydrophobic character of Ar‐CF3 can effectively prevent water flooding of the Fe/N/C catalyst layer, and thus form robust mass‐transport channels for gas−liquid two‐phase flow. Simultaneously, both electron‐withdrawing and hydrophobic properties considerably suppress the oxidative corrosion of the carbon matrix that hosts the catalytically active sites. Therefore, fluorinated Fe/N/C could perform stably over 100 h at 0.5 V with a current density of 0.56 A cm−2 in a H2−O2 PEMFC. Even when the cell voltage increased to 0.6 V, only 15 % performance was lost after 100 h operation.
Comparing the Relative Reactivities of Structurally Varied Alcohols toward Electrochemically Generated Superoxide
Authors: Lauw Sherman J. L. , Chiang Zhong , Lee Jazreen H. Q. , Webster Richard D.
Published: November 2017

Superoxide (O2.−) is a free‐radical anion of the reactive oxygen species (ROS) family. In the present study, the relative reactivities of 14 structurally varied aliphatic alcohols toward electrochemically generated O2.− were investigated in solutions of N,N‐dimethylformamide by using cyclic voltammetry (CV). Upon the stepwise addition of each substrate, the chemical reversibility of the one‐electron voltammetric reduction of the dioxygen (O2) to O2.− was found to decrease, which enabled the extent of radical inhibition to be determined by measuring the resultant oxidative peak current (Ipa) magnitudes on the reverse scan of the CV. Based on the electrochemical responses gathered, best fit plots of the percentage decrease in the anodic peak current (%ΔIpa) against the concentration of substrate added were obtained and compared according to the different classes of alcohols that were examined (linear, fluorinated, branched, and poly‐hydroxylated). In addition, different parameters, such as electronic effects, steric effects, degree of hydroxylation, and kinetic effects that affect the O2.− scavenging abilities of the alcohols, are also discussed.
NIR hyperspectral imaging spectroscopy and chemometrics for the discrimination of roots and crop residues extracted from soil samples
Authors: Eylenbosch Damien , Bodson Bernard , Baeten Vincent , Fernández Pierna Juan Antonio
Published: November 2017

Roots play a major role in plant development. Their study in field conditions is important to identify suitable soil management practices for sustainable crop productions. Soil coring, which is a common method in root production measurement, is limited in sampling frequency due to the hand‐sorting step. This step, needed to sort roots from other elements extracted from soil cores like crop residues, is time consuming, tedious, and vulnerable to operator ability and subjectivity. To get rid of the cumbersome hand‐sorting step, avoid confusion between these elements, and reduce the time needed to quantify roots, a new procedure, based on near‐infrared hyperspectral imaging spectroscopy and chemometrics, has been proposed. It was tested to discriminate roots of winter wheat (Triticum aestivum L.) from crop residues and soil particles. Two algorithms (support vector machine and partial least squares discriminant analysis) have been compared for discrimination analysis. Models constructed with both algorithms allowed the discrimination of roots from other elements, but the best results were reached with models based on support vector machine. The ways to validate models, with selected spectra or with hyperspectral images, provided different kinds of information but were complementary. This new procedure of root discrimination is a first step before root quantification in soil samples with near‐infrared hyperspectral imaging. The results indicate that the methodology could be an interesting tool to improve the understanding of the effect of tillage or fertilization, for example, on root system development.
A General Asymmetric Formal Synthesis of Aza‐Baylis–Hillman Type Products under Bifunctional Catalysis
Authors: Frías María , Carrasco Ana Cristina , Fraile Alberto , Alemán José
Published: November 2017

A new organocatalytic strategy for the synthesis of enantioenriched aza‐Baylis–Hillman type products via a frustrated vinylogous reaction is presented. This process proceeds under mild conditions with good yields, completed Z/E selectivity and excellent enantioselectivities. Moreover, easy derivatizations of the final products led to important building blocks of organic synthesis such as 1,3‐aminoalcohols and Lewis base catalysts.
Difunctionalization of Alkynes: Synthesis of Novel Fluoropolymer Materials
Authors: Wang Qiang , Yu Xiwen , Jin Jiani , Wu Yang , Liang Yongmin
Published: November 2017

A Pd‐catalyzed multi‐component carbonylative difluoroalkylation/perfluoroalkylation through the alkyne difunctionalization process has been developed. Besides, new functional fluoropolymer materials have been successfully synthesized. Owing to the presence of the fluorine element, the materials present excellent chemical resistance, high‐temperature‐resistance and outstanding hydrophobicity simultaneously, which may significantly make them great appealing in the industrial production and life science as well.
AquaMMapS: An Alternative Tool to Monitor the Role of Water Molecules During Protein–Ligand Association
Authors: Cuzzolin Alberto , Deganutti Giuseppe , Salmaso Veronica , Sturlese Mattia , Moro Stefano
Published: November 2017

Unquestionably, water appears to be an active player in the noncovalent protein–ligand binding process, as it can either bridge interactions between protein and ligand or can be replaced by the bound ligand. Accordingly, in the last decade, alternative computational methodologies have been sought with the aim of predicting the position and thermodynamic profile of water molecules (i.e., hydration sites) in the binding site using either the ligand‐bound or ligand‐free protein conformation. Herein, we present an alternative approach, named AquaMMapS, that provides a three‐dimensional sampling of putative hydration sites. Interestingly, AquaMMapS can post‐inspect molecular dynamics (MD) trajectories obtained from different MD engines using indifferently crystallographic or docking‐driven structures as a starting point. Moreover, AquaMMapS is naturally integrated into supervised molecular dynamics (SuMD) simulations, presenting the possibility to inspect hydration sites during the ligand–protein association process. Finally, a penalty scoring method, named AquaMMapScoring(AMS), was developed to evaluate the number and nature of the water molecules displaced by a ligand approaching its binding site during the binding event, guiding a medicinal chemist to explore the most suitable regions of a ligand that can be decorated either with or without interfering with the interaction networks mediated by water molecules with specific recognition regions of the protein.
Preliminary Evaluation of Artemisinin–Cholesterol Conjugates as Potential Drugs for the Treatment of Intractable Forms of Malaria and Tuberculosis
Authors: Morake Mokhitli , Coertzen Dina , Ngwane Andile , Wentzel Johannes F. , Wong Ho Ning , Smit Frans J. , Birkholtz Lyn‐Marie , Pietersen Ray‐Dean , Baker Bienyameen , Wiid Ian , N'Da David D. , Haynes Richard K.
Published: November 2017

To evaluate the feasibility of developing drugs that may be active against both malaria and tuberculosis (TB) by using in part putative cholesterol transporters in the causative pathogens and through enhancement of passive diffusion in granulomatous TB, artemisinin–cholesterol conjugates were synthesized by connecting the component molecules through various linkers. The compounds were screened in vitro against Plasmodium falciparum (Pf) and Mycobacterium tuberculosis (Mtb). Antimalarial activities (IC50) against Pf drug‐sensitive NF54, and drug‐resistant K1 and W2 strains ranged from 0.03–2.6, 0.03–1.9, and 0.02–1.7 μm. Although the compounds are less active than the precursor artemisinin derivatives, the cholesterol moiety renders the compounds relatively insoluble in the culture medium, and variation in solubilities among the different compounds may reflect in the range of efficacies observed. Activities against Mtb H37Rv were assessed using a standardized colony‐forming unit (CFU) assay after 24 h pretreatment of cultures with each of the compounds. Percentage inhibition ranged from 3–38 % and 18–52 % at 10 and 80 μm, respectively. Thus, in contrast to the comparator drug artemether, the conjugates display enhanced activities. The immediate aims include the preparation of conjugates with enhanced aqueous solubilities, assays against malaria and TB in vivo, and for TB, assays using an infected macrophage model and assessment of granuloma influx.
Lung cancer incidence and the strength of municipal smoke‐free ordinances
Authors: Hahn Ellen J. , Rayens Mary Kay , Wiggins Amanda T. , Gan Wenqi , Brown Holly M. , Mullett Timothy W.
Published: November 2017

BACKGROUND

Smoke‐free laws reduce disease prevalence. The impact of municipal smoke‐free laws on lung cancer incidence in Kentucky was examined. The authors hypothesized that lung cancer incidence rates would be associated with the strength of smoke‐free laws.

METHODS

This was a secondary analysis of 83,727 Kentucky residents aged ≥ 50 years who were newly diagnosed with lung cancer from 1995 to 2014. In 2014, 33 municipalities had 1 or more smoke‐free laws. County‐level characteristics included adult smoking rate, sex, race/ethnicity, income, physician supply, observed radon values, and rurality.

RESULTS

Individuals living in communities with comprehensive smoke‐free laws were 7.9% less likely than those living in communities without smoke‐free protections to be diagnosed with lung cancer. The difference in lung cancer incidence between counties with moderate/weak laws and those without laws was not significant.

CONCLUSIONS

Comprehensive smoke‐free laws were associated with fewer new cases of lung cancer, whereas weak or moderate smoke‐free laws did not confer the same benefit. One hundred percent smoke‐free laws, covering all workers and the public with few or no exceptions, may be key in reducing new cases of lung cancer. Cancer 2018;124:374‐80. © 2017 American Cancer Society.
The Role of Copper Speciation in the Low Temperature Oxidative Upgrading of Short Chain Alkanes over Cu/ZSM‐5 Catalysts
Authors: Armstrong Robert D. , Peneau Virginie , Ritterskamp Nadine , Kiely Christopher J. , Taylor Stuart H. , Hutchings Graham J.
Published: November 2017

Partial oxidative upgrading of C1–C3alkanes over Cu/ZSM‐5 catalysts prepared by chemical vapour impregnation (CVI) has been studied. The undoped ZSM‐5 support is itself able to catalyse selective oxidations, for example, methane to methanol, using mild reaction conditions and the green oxidant H2O2. Addition of Cu suppresses secondary oxidation reactions, affording methanol selectivities of up to 97 %. Characterisation studies attribute this ability to population of specific Cu sites below the level of total exchange (Cu/Al<0.5). These species also show activity for radical‐based methane oxidation, with productivities exceeding those of the parent zeolite supports. When tested for ethane and propane oxidation reactions, comparable trends are observed.
Design and optical study of a microwave plasma torch in nitrogen used for the evaporation of aluminium wires
Authors: Pipa A.V. , Sushentsev D. , Hamann S. , Dufloux C. , Ionikh Yu.Z. , Hannemann M. , Wiese M. , Röpcke J. , Wollweber J.
Published: November 2017

A microwave torch in nitrogen has been designed for the evaporation of aluminium (Al) wires potentially to be used for the synthesis of aluminium nitride (AlN). The torch, created on the tip of a metallic nozzle, is compatible with vacuum conditions and can be operated in continuous mode up to atmospheric pressure. Al wires to be evaporated are fed through the axis of the nozzle. Time‐resolved photography is applied to analyse the time evolution and stability of the interaction of the Al wire with the discharge. Optical emission spectroscopy is used (a) for the determination of the gas temperature of the active discharge, which is found to be in the range 1500–3500 K depending on the experimental conditions, and (b) for the estimation of the densities of Al and N atoms in the afterglow region, which are in the range 1011–1012 and of 1013–1014 cm−3, respectively. It is found that the part of the Al wire that is directly exposed to the nitrogen torch absorbs a considerable amount of the microwave energy, supporting its evaporation. In addition, the dissociation of molecular nitrogen has to be considered as an important process of power dissipation. Further technical development of the torch is necessary for the envisaged synthesis of AlN.
The beneficial effects of probiotic administration on wound healing and metabolic status in patients with diabetic foot ulcer: A randomized, double‐blind, placebo‐controlled trial
Authors: Mohseni Sima , Bayani Masomeh , Bahmani Fereshteh , Tajabadi‐Ebrahimi Maryam , Bayani Mohammad Ali , Jafari Parvaneh , Asemi Zatollah
Published: November 2017

Background

This study was conducted to evaluate the effects of probiotic supplementation on wound healing and metabolic status in subjects with diabetic foot ulcer (DFU).

Methods

This randomized, double‐blind, placebo‐controlled trial was conducted among 60 subjects (aged 40‐85 years old) with grade 3 diabetic foot ulcer. Individuals were randomly divided into 2 groups (30 subjects each group) to receive either probiotic or placebo daily for 12 weeks.

Results

After the 12‐week intervention, compared with the placebo, probiotic supplementation led to significant reductions in ulcer length (−1.3 ± 0.9 vs. −0.8 ± 0.7 cm, P = .01), width (−1.1 ± 0.7 vs. −0.7 ± 0.7 cm, P = .02), and depth (−0.5 ± 0.3 vs. −0.3 ± 0.3 cm, P = .02). Furthermore, significant reductions in fasting plasma glucose (−29.6 ± 30.3 vs. −5.8 ± 39.8 mg/dL, P = .01), serum insulin concentrations (−4.3 ± 7.9 vs. +0.4 ± 8.5 μIU/mL, P = .03), and haemoglobin A1c (−0.6 ± 0.5 vs. −0.2 ± 0.4%, P = .003) and a significant rise in the quantitative insulin sensitivity check index (+0.01 ± 0.01 vs. −0.01 ± 0.02, P = .003) were seen following supplementation of probiotic compared with the placebo. Additionally, compared with the placebo, probiotic supplementation resulted in significant decreases in serum total cholesterol (−4.8 ± 16.1 vs. +7.0 ± 27.1 mg/dL, P = .04), high‐sensitivity C‐reactive protein (−9.0 ± 14.7 vs. −1.7 ± 8.6 mg/L, P = .02), plasma malondialdehyde (−0.8 ± 0.8 vs. −0.2 ± 0.8 μmol/L, P = .001), and significant increases in plasma nitric oxide (+6.2 ± 8.2 vs. +0.8 ± 8.0 μmol/L, P = .01) and total antioxidant capacity concentrations (+179.3 ± 97.2 vs. −85.1 ± 203.4 mmol/L, P < .001).

Conclusions

Overall, probiotic supplementation for 12 weeks among subjects with diabetic foot ulcer had beneficial effects on ulcer size, glycaemic control, total cholesterol, high‐sensitivity C‐reactive protein, plasma nitric oxide, total antioxidant capacity, and malondialdehyde levels.
An approach based on the total‐species accumulation curve and higher taxon richness to estimate realistic upper limits in regional species richness
Authors: Bevilacqua Stanislao , Ugland Karl Inne , Plicanti Adriana , Scuderi Danilo , Terlizzi Antonio
Published: November 2017

Most of accumulation curves tend to underestimate species richness, as they do not consider spatial heterogeneity in species distribution, or are structured to provide lower bound estimates and limited extrapolations. The total‐species (T–S) curve allows extrapolations over large areas while taking into account spatial heterogeneity, making this estimator more prone to attempt upper bound estimates of regional species richness. However, the T–S curve may overestimate species richness due to (1) the mismatch among the spatial units used in the accumulation model and the actual units of variation in β‐diversity across the region, (2) small‐scale patchiness, and/or (3) patterns of rarity of species. We propose a new framework allowing the T–S curve to limit overestimation and give an application to a large dataset of marine mollusks spanning over 11 km2 of subtidal bottom (W Mediterranean). As accumulation patterns are closely related across the taxonomic hierarchy up to family level, improvements of the T–S curve leading to more realistic estimates of family richness, that is, not exceeding the maximum number of known families potentially present in the area, can be considered as conducive to more realistic estimates of species richness. Results on real data showed that improvements of the T–S curve to accounts for true variations in β‐diversity within the sampled areas, small‐scale patchiness, and rarity of families led to the most plausible richness when all aspects were considered in the model. Data on simulated communities indicated that in the presence of high heterogeneity, and when the proportion of rare species was not excessive (>2/3), the procedure led to almost unbiased estimates. Our findings highlighted the central role of variations in β‐diversity within the region when attempting to estimate species richness, providing a general framework exploiting the properties of the T–S curve and known family richness to estimate plausible upper bounds in γ‐diversity.
Relative contribution of neutral and deterministic processes in shaping fruit‐feeding butterfly assemblages in Afrotropical forests
Authors: Aduse‐Poku Kwaku , Molleman Freerk , Oduro William , Oppong Samuel K. , Lohman David J. , Etienne Rampal S.
Published: November 2017

The unified neutral theory of biodiversity and biogeography has gained the status of a quantitative null model for explaining patterns in ecological (meta)communities. The theory assumes that individuals of trophically similar species are functionally equivalent. We empirically evaluate the relative contribution of neutral and deterministic processes in shaping fruit‐feeding butterfly assemblages in three tropical forests in Africa, using both direct (confronting the neutral model with species abundance data) and indirect approaches (testing the predictions of neutral theory using data other than species abundance distributions). Abundance data were obtained by sampling butterflies using banana baited traps set at the forest canopy and understorey strata. Our results indicate a clear consistency in the kind of species or species groups observed at either the canopy or understorey in the three studied communities. Furthermore, we found significant correlation between some flight‐related morphological traits and species abundance at the forest canopy, but not at the understorey. Neutral theory's contribution to explaining our data lies largely in identifying dispersal limitation as a key process regulating fruit‐feeding butterfly community structure. Our study illustrates that using species abundance data alone in evaluating neutral theory can be informative, but is insufficient. Species‐level information such as habitat preference, host plants, geographical distribution, and phylogeny is essential in elucidating the processes that regulate biodiversity community structures and patterns.
Timescale effects on the environmental control of carbon and water fluxes of an apple orchard
Authors: Montagnani Leonardo , Zanotelli Damiano , Tagliavini Massimo , Tomelleri Enrico
Published: November 2017

Model parameterization and validation of earth–atmosphere interactions are generally performed using a single timescale (e.g., nearly instantaneous, daily, and annual), although both delayed responses and hysteretic effects have been widely recognized. The lack of consideration of these effects hampers our capability to represent them in empirical‐ or process‐based models. Here we explore, using an apple orchard ecosystem in the North of Italy as a simplified case study, how the considered timescale impacts the relative importance of the single environmental variables in explaining observed net ecosystem exchange (NEE) and evapotranspiration (ET). Using 6 years of eddy covariance and meteorological information as input data, we found a decay of the relative importance of the modeling capability of photosynthetically active radiation in explaining both NEE and ET moving from half‐hourly to seasonal timescale and an increase in the relative importance of air temperature (T) and VPD. Satellite NDVI, used as proxy of leaf development, added little improvement to overall modeling capability. Increasing the timescale, the number of variables needed for parameterization decreased (from 5 to 1), while the proportion of variance explained by the model increased (r2 from 0.56–0.78 to 0.85–0.90 for NEE and ET respectively). The wavelet coherence and the phase analyses showed that the two variables that increased their relative importance when the scale increased (T, VPD) were not in phase at the correlation peak of both ET and NEE. This phase shift in the time domain corresponds to a hysteretic response in the meteorological variables domain. This work confirms that the model parameterization should be performed using parameters calculated at the appropriate scale. It suggests that in managed ecosystems, where the interannual variability is minimized by the agronomic practices, the use of timescales large enough to include hysteretic and delayed responses reduces the number of required input variables and improves their explanatory capacity.
Drivers of apoplastic freezing in gymnosperm and angiosperm branches
Authors: Lintunen Anna , Mayr Stefan , Salmon Yann , Cochard Hervé , Hölttä Teemu
Published: November 2017

It is not well understood what determines the degree of supercooling of apoplastic sap in trees, although it determines the number and duration of annual freeze–thaw cycles in a given environment. We studied the linkage between apoplastic ice nucleation temperature, tree water status, and conduit size. We used branches of 10 gymnosperms and 16 angiosperms collected from an arboretum in Helsinki (Finland) in winter and spring. Branches with lower relative water content froze at lower temperatures, and branch water content was lower in winter than in spring. A bench drying experiment with Picea abies confirmed that decreasing branch water potential decreases apoplastic ice nucleation temperature. The studied angiosperms froze on average 2.0 and 1.8°C closer to zero Celsius than the studied gymnosperms during winter and spring, respectively. This was caused by higher relative water content in angiosperms; when branches were saturated with water, apoplastic ice nucleation temperature of gymnosperms increased to slightly higher temperature than that of angiosperms. Apoplastic ice nucleation temperature in sampled branches was positively correlated with xylem conduit diameter as shown before, but saturating the branches removed the correlation. Decrease in ice nucleation temperature decreased the duration of freezing, which could have an effect on winter embolism formation via the time available for gas escape during ice propagation. The apoplastic ice nucleation temperature varied not only between branches but also within a branch between consecutive freeze–thaw cycles demonstrating the stochastic nature of ice nucleation.
CXCL4 is a novel inducer of human Th17 cells and correlates with IL‐17 and IL‐22 in psoriatic arthritis
Authors: Affandi Alsya J. , Silva‐Cardoso Sandra C. , Garcia Samuel , Leijten Emmerik F. A. , van Kempen Tessa S. , Marut Wioleta , van Roon Joel A. G. , Radstake Timothy R. D. J.
Published: November 2017

CXCL4 regulates multiple facets of the immune response and is highly upregulated in various Th17‐associated rheumatic diseases. However, whether CXCL4 plays a direct role in the induction of IL‐17 production by human CD4+ T cells is currently unclear. Here, we demonstrated that CXCL4 induced human CD4+ T cells to secrete IL‐17 that co‐expressed IFN‐γ and IL‐22, and differentiated naïve CD4+ T cells to become Th17‐cytokine producing cells. In a co‐culture system of human CD4+ T cells with monocytes or myeloid dendritic cells, CXCL4 induced IL‐17 production upon triggering by superantigen. Moreover, when monocyte‐derived dendritic cells were differentiated in the presence of CXCL4, they orchestrated increased levels of IL‐17, IFN‐γ, and proliferation by CD4+ T cells. Furthermore, the CXCL4 levels in synovial fluid from psoriatic arthritis patients strongly correlated with IL‐17 and IL‐22 levels. A similar response to CXCL4 of enhanced IL‐17 production by CD4+ T cells was also observed in patients with psoriatic arthritis. Altogether, we demonstrate that CXCL4 boosts pro‐inflammatory cytokine production especially IL‐17 by human CD4+ T cells, either by acting directly or indirectly via myeloid antigen presenting cells, implicating a role for CXCL4 in PsA pathology.
From Heptacoordinated CrIII Complexes with Cyanide or Isothiocyanate Apical Groups to 1D Heterometallic Assemblages with All‐Pentagonal‐Bipyramid Coordination Geometries
Authors: Pichon Céline , Elrez Bahjat , Béreau Virginie , Duhayon Carine , Sutter Jean‐Pascal
Published: November 2017

A series of heptacoordinated CrIII complexes with either cyano or thiocyanato ligands in the apical positions are described and their ability to act as metallo‐ligands is illustrated. These compounds contain a pentadentate ligand, H2LN3O2R [H2LN3O2R = 2,6‐diacetylpyridinebis(benzoylhydrazone) for R = Ph, 2,6‐diacetylpyridinebis(4‐biphenylylcarbonylhydrazone) for R = biPh], chelated in the equatorial positions of the Cr metal center, thus imposing a bipyramidal‐pentagonal geometry on the complexes. The two axial water molecules of the precursor complexes [Cr(HLN3O2Ph)(H2O)2](NO3)2 (1) and [Cr(HLN3O2biPh)(H2O)2](NO3)2 (2) were easily exchanged with coordinating substituents such as CN– or NCS– to yield K[Cr(LN3O2Ph)(CN)2] (3), K[Cr(LN3O2biPh)(CN)2] (4), and [Cr(HLN3O2Ph)(NCS)2] (5). The reaction of 3 with MnII complexes [Mn(LN5)(H2O)2]Cl2 and [Mn(LN5R,R)Cl2] (LN5 and LN5RR represent macrocyclic pentadentate ligands: LN5 = 2,13‐dimethyl‐3,6,9,12,18‐pentaazabicyclo[12.3.1]octadeca‐1(18),2,12,14,16‐pentaene, and LN5RR = 2,21‐dimethyl‐(4R,9R,14R,‐19R)‐3,10,13,20,26‐pentaazatetracyclo[20.3.1.04,9.014,19]hexacosa‐1(26),22(23),24‐triene) yielded the 1D coordination polymers [Cr(LN3O2Ph)(CN)2Mn(LN5)](PF6) (6a,b) and the chiral chain [Cr(LN3O2Ph)(CN)2Mn(LN5R,R)](PF6)0.75Cl0.25 (7), which are constructed of only heptacoordinated metal centers. The assembly of 4 with [Mn(LN5)(H2O)2]Cl2 gave the neutral trinuclear complex [{Cr(LN3O2biPh)(CN)2}2Mn(LN5)] (8), whereas the association of 3 with the NiII Schiff‐base complex [Ni(valpn)] [H2(valpn) = 1,3‐propanediylbis(2‐iminomethylene‐6‐methoxyphenol] led to the discrete compound K[Ni(valpn)Cr(LN3O2Ph)(CN)2] (9). The crystal structures and magnetic properties of all the compounds are reported.
Electronic Interactions between Ferrocenyl Units Facilitated by the Cobalt Bis(dicarbollide) Anion Linker: An Experimental and DFT Study
Authors: Pichaandi Kothanda Rama , Safronov Lakshmi Nilakantan, Alexander V. , Sevryugina Yulia V. , Jalisatgi Satish S. , Hawthorne M. Frederick
Published: November 2017

The electronic interaction between two terminal ferrocenyl units connected by the cobalt bis(dicarbollide) anion linker was investigated. The bis(ferrocenylethynyl)cobalt bis(dicarbollide) anion (3) linking the two ferrocenyl units with the cobalt bis(dicarbollide) anion was synthesized by the reaction of a zinc derivative of ethynylferrocene with the diiodocobalt bis(dicarbollide) anion using Pd0 catalyst in 75 % yield. Complex 3 was unambiguously characterized by NMR and IR spectroscopy, mass spectrometry, and single‐crystal X‐ray crystallography. The X‐ray structure of 3 reveals that the two ferrocenyl units are perpendicular to each other with a total distance of 1.86 nm between the two Fe metal centers. The cyclic voltammogram of 3 shows a single oxidation potential corresponding to the two ferrocenyl units. Time‐dependent density functional theory (TD‐DFT) studies on complex 3 in tandem with UV/Vis spectroscopic analysis indicate the dominance of the dicarbollide moiety in the LUMOs, and HOMO→LUMO transitions at 435 nm illustrate the charge transfer from the two ferrocenyl units to the cobalt bis(dicarbollide) linker.
Mononuclear and One‐Dimensional Cobalt(II) Complexes with the 3,6‐Bis(picolylamino)‐1,2,4,5‐tetrazine Ligand
Authors: Stetsiuk Oleh , El‐Ghayoury Abdelkrim , Lloret Francesc , Julve Miguel , Avarvari Narcis
Published: November 2017

We describe herein the synthesis and structural characterization of a tetrazine‐based bis(picolylamine) ligand, namely, N3,N6‐bis(pyridin‐2‐ylmethyl)‐1,2,4,5‐tetrazine‐3,6‐diamine (L, 1), which was prepared by the direct reaction between 2 equiv. of picolylamine and 3,6‐dichloro‐1,2,4,5‐tetrazine. Its reaction with cobalt(II) hexafluoroacetylacetonate hydrate afforded the mononuclear complex [Co(hfac)2L]·CH3CN (2, Hhfac = hexafluoroacetylacetone) and the chain compound {[Co(hfac)2(µ‐L)][Co(hfac)2(CH3OH)2]}n (3). The crystal structures of 1–3 were determined by X‐ray structure analysis. The metal centre in 2 is trischelated by two hfac ligands and one picolylamine unit. The two crystallographically independent cobalt(II) ions in 3 (Co1 and Co2) are six‐coordinate. Two bidentate hfac groups in equatorial positions and two trans‐positioned pyridine nitrogen atoms build the coordination polyhedron around Co1 to form a neutral zigzag chain compound, which cocrystallizes with the mononuclear species trans‐[Co2(hfac)2(CH3OH)2]. The magnetic properties of 2 and 3 were investigated in the temperature range 1.9–300 K. The decrease of the χMT values of 2 and 3 upon cooling is mainly due to the depopulation of the higher energy Kramers doublets of the magnetically isolated six‐coordinate cobalt(II) ions. Alternating‐current (ac) magnetic susceptibility measurements of 2 and 3 revealed the occurrence of frequency‐dependent out‐of‐phase signals under applied direct‐current (dc) fields at very low temperatures, and this result is indicative of single‐ion magnet (SIM) behaviour.
Basicity of N‐(Tetramesityltetraphosphacyclopentylidene)cyclohexylamine: An Unusual Diphospha(III)guanidine Derivative
Authors: Adhikari Anup Kumar , Grell Toni , Lönnecke Peter , Hey‐Hawkins Evamarie
Published: November 2017

Invited for the cover of this issue is the group of Evamarie Hey‐Hawkins at the University of Leipzig, Germany. The cover image shows the pKa value of the unusual cyclic hetero‐oligophosphane cyclo‐P4Mes4C(NCy).
The unique effects of blatant dehumanization on attitudes and behavior towards Muslim refugees during the European ‘refugee crisis’ across four countries
Authors: Bruneau Emile , Kteily Nour , Laustsen Lasse
Published: November 2017

Blatant dehumanization has recently been demonstrated to predict negative outgroup attitudes and behaviors. Here, we examined blatant dehumanization of Muslim refugees during the ‘Refugee Crisis’ among large samples in four European countries: the Czech Republic (N = 1307), Hungary (N = 502), Spain (N = 1049), and Greece (N = 934). Our results suggest that blatant dehumanization of Muslim refugees is (a) prevalent among Europeans, and (b) uniquely associated with anti‐refugee attitudes and behavior, beyond political ideology, prejudice, and—of particular relevance to the refugee crisis—empathy. We also find that blatant dehumanization of Muslim refugees is significantly higher and more strongly associated with intergroup behavior in the Eastern European countries (especially the Czech Republic) than in Spain and Greece. Examining a range of outgroup targets beyond refugees, our results further illustrate that blatant dehumanization is not purely an ethnocentric bias: while individuals across contexts feel warmer towards their group than all others, they rate several high‐status outgroups as equally or more fully ‘evolved and civilized’ than the ingroup. Our research extends theoretical understanding of blatant dehumanization, and suggests that blatant dehumanization plays an important and independent role in the rejection of Muslim refugees throughout Europe.
Use of Screen‐printed Electrodes Modified by Prussian Blue and Analogues in Sensing of Cysteine
Authors: Bonacin Juliano A. , Dos Santos Pãmyla L. , Katic Vera , Foster Christopher W. , Banks Craig E.
Published: November 2017

The utilisation of screen‐printing technology allows for a mass scalable approach for the production of electrochemical screen‐printed electrodes (SPEs) and the presence of a redox mediator can add new possibilities to the electrochemical properties of the SPEs. Among the materials used as redox mediators, cyanidoferrates polymers can be used for electro‐oxidation of cysteine. In this work, two monomers, namely, [Fe(CN)6]4− and [Fe(CN)5NH3]3− were used to produce Prussian blue (PB) and Prussian blue‐Ammine (PB‐Ammine), respectively. In addition, two modification methods were compared, firstly via a drop‐casting and secondly by the incorporation of these materials into a printable ink. The SPE modified by PB‐Ammine (drop‐casting) exhibits the highest electroactive area, however the highest heterogeneous rate constant was found with the SPE modified by PB‐Ammine that was incorporated into the ink. The highest value of the constant of electro‐oxidation of cysteine and lowest limit of detection was also observed in the SPE modified by PB incorporated into the ink. These studies suggest that the electrocatalytic properties of SPE modified by PB and PB‐Ammine are dependent upon the availability of Fe3+ catalytic sites and the increased kinetics of the chemical reaction between the catalytic sites and the analyte.
Proteomics analysis of human breast milk to assess breast cancer risk
Authors: Aslebagh Roshanak , Channaveerappa Devika , Arcaro Kathleen F. , Darie Costel C.
Published: November 2017

Detection of breast cancer (BC) in young women is challenging because mammography, the most common tool for detecting BC, is not effective on the dense breast tissue characteristic of young women. In addition to the limited means for detecting their BC, young women face a transient increased risk of pregnancy‐associated BC. As a consequence, reproductively active women could benefit significantly from a tool that provides them with accurate risk assessment and early detection of BC. One potential method for detection of BC is biochemical monitoring of proteins and other molecules in bodily fluids such as serum, nipple aspirate, ductal lavage, tear, urine, saliva and breast milk. Of all these fluids, only breast milk provides access to a large volume of breast tissue, in the form of exfoliated epithelial cells, and to the local breast environment, in the form of molecules in the milk. Thus, analysis of breast milk is a non‐invasive method with significant potential for assessing BC risk. Here we analyzed human breast milk by mass spectrometry (MS)‐based proteomics to build a biomarker signature for early detection of BC. Ten milk samples from eight women provided five paired‐groups (cancer versus control) for analysis of dysregulatedproteins: two within woman comparisons (milk from a diseased breast versus a healthy breast of the same woman) and three across women comparisons (milk from a woman with cancer versus a woman without cancer). Despite a wide range in the time between milk donation and cancer diagnosis (cancer diagnosis occurred from 1 month before to 24 months after milk donation), the levels of some proteins differed significantly between cancer and control in several of the five comparison groups. These pilot data are supportive of the idea that molecular analysis of breast milk will identify proteins informative for early detection and accurate assessment of BC risk, and warrant further research. Data are available via ProteomeXchange with identifier PXD007066.
Integrated microfluidic biosensing platform for simultaneous confocal microscopy and electrophysiological measurements on bilayer lipid membranes and ion channels
Authors: Schulze Greiving Verena C. , de Boer Hans L. , Bomer Johan G. , van den Berg Albert , Le Gac Séverine
Published: November 2017

Combining high‐resolution imaging and electrophysiological recordings is key for various types of experimentation on lipid bilayers and ion channels. Here, we propose an integrated biosensing platform consisting of a microfluidic cartridge and a dedicated chip‐holder to conduct such dual measurements on suspended lipid bilayers, in a user‐friendly manner. To illustrate the potential of the integrated platform, we characterize lipid bilayers in terms of thickness and fluidity while simultaneously monitoring single ion channel currents. For that purpose, POPC lipid bilayers are supplemented with a fluorescently‐tagged phospholipid (NBD‐PE, 1% mol) for Fluorescence Recovery After Photobleaching (FRAP) measurements and a model ion channel (gramicidin, 1 nM). These combined measurements reveal that NBD‐PE has no effect on the lipid bilayer thickness while gramicidin induces thinning of the membrane. Furthermore, the presence of gramicidin does not alter the lipid bilayer fluidity. Surprisingly, in lipid bilayers supplemented with both probes, a reduction in gramicidin open probability and lifetime is observed compared to lipid bilayers with gramicidin only, suggesting an influence of NBD‐PE on the gramicidin ion function. Altogether, our proposed microfluidic biosensing platform in combination with the herein presented multi‐parametric measurement scheme paves the way to explore the interdependent relationship between lipid bilayer properties and ion channel function.
CE‐XRF–initial steps toward a non‐invasive elemental sensitive detector for liquid separations
Authors: Tyssebotn Inger Marie Bergø , Fittschen Andreas , Fittschen Ursula Elisabeth Adriane
Published: November 2017

The toxicity, bioavailability, and mobilization of elements within the biosphere is dependent on its species. CE has emerged as a strong separation technique for elemental speciation. Conventionally, CE has been coupled with UV‐vis, C4D, PIXE (proton‐induced X‐ray emission), and ICP‐MS. UV‐vis and C4D are not elemental sensitive detection methods, PIXE requires the etching of the detection window resulting in a very brittle capillary, and ICP‐MS is an expensive large footprint instrument. Here, we aim to develop an elemental specific detector, XRF (X‐ray fluorescence spectrometry), for use with CE. A custom‐built micro‐XRF was tested and static LODs were determined for 19 elements (Ca‐U) with both unmodified (20‐926 ppm) and modified capillaries (20‐291 ppm). A custom‐built CE was combined with the micro‐XRF and separation of Ca2+ and Co2+ was obtained. Sr2+ coeluted with Ca2+ in the mixture, but because of the elemental sensitivity of XRF, the Sr and Ca signals could be separated. After successful testing of the micro‐XRF, the feasibility of using a low‐cost X‐ray source and detector was tested. Even lower LODs were obtained for Ga and Rb, showing the feasibility of a smaller, low‐cost XRF unit as an elemental specific detector. However, the buffer selection that can be conveniently used with XRF is currently limited due to capillary corrosion, likely correlated to radiolysis.
Parallel probing of drug uptake of single cancer cells on a microfluidic device
Authors: Yang Yoonsun , Le Gac Séverine , Terstappen Leon WMM , Rho Hoon Suk
Published: November 2017

Drug resistance is frequently developing during treatment of cancer patients. Intracellular drug uptake is one of the important characteristics to understand mechanism of drug resistance. However, the heterogeneity of cancer cells requires the investigation of drug uptake at the single cell level. Here, we developed a microfluidic device for parallel probing of drug uptake. We combined a v‐type valve and peristaltic pumping to select individual cells from a pool of prostate cancer cells (PC3) and place them successively in separate cell chambers in which they were exposed to the drug. Six different concentrations of doxorubicin, a naturally fluorescent anti‐cancer drug, were created in loop‐shaped reactors and exposed to the cell in closed 2 nL volume chambers. Monitoring every single cell over time in 18 parallel chambers revealed increased intracellular fluorescence intensity according to the dose of doxorubicin, as well as nuclear localization of the fluorescent drug after 2 h of incubation. The herein proposed technology demonstrated a first series of proof of concept experiments and it shows high potential to use for probing drug sensitivity of single cancer cell.
Egg chemoattractants moderate intraspecific sperm competition
Authors: Lymbery Rowan A. , Kennington W. Jason , Evans Jonathan P.
Published: November 2017

Interactions among eggs and sperm are often assumed to generate intraspecific variation in reproductive fitness, but the specific gamete-level mechanisms underlying competitive fertilization success remain elusive in most species. Sperm chemotaxis–the attraction of sperm by egg-derived chemicals—is a ubiquitous form of gamete signaling, occurring throughout the animal and plant kingdoms. The chemical cues released by eggs are known to act at the interspecific level (e.g., facilitating species recognition), but recent studies have suggested that they could have roles at the intraspecific level by moderating sperm competition. Here, we exploit the experimental tractability of a broadcast spawning marine invertebrate to test this putative mechanism of gamete-level sexual selection. We use a fluorescently labeled mitochondrial dye in mussels to track the real-time success of sperm as they compete to fertilize eggs, and provide the first direct evidence in any species that competitive fertilization success is moderated by differential sperm chemotaxis. Furthermore, our data are consistent with the idea that egg chemoattractants selectively attract ejaculates from genetically compatible males, based on relationships inferred from both nuclear and mitochondrial genetic markers. These findings for a species that exhibits the ancestral reproductive strategy of broadcast spawning have important implications for the numerous species that also rely on egg chemoattractants to attract sperm, including humans, and have potentially important implications for our understanding of the evolutionary cascade of sexual selection.
Balancing board? The effects of board independence and capital on firms offering work‐family benefits
Authors: Mullins Frank , Holmes Jeanne
Published: November 2017

While prior research demonstrates the strategic human resource (HR) advantages associated with offering work–family benefits (WFBs), firms continue to be reluctant in providing their employees with these benefits. Drawing on the corporate governance and stakeholder orientation literatures, this study examines the role of board independence and capital for WFBs being offered in publicly‐traded firms. Our results demonstrate that various director independence and capital attributes are related to the firm offering WFBs. Specifically, board directors who are outsiders, women, and holders of additional directorships, with their broad stakeholder orientation, increase the likelihood of WFBs being offered by the firm [Correction added on December 14, 2017, after first online publication: the preceding sentence has been updated to clarify the findings of the study.]. These findings are of importance to HR practitioners considering the influence that corporate boards can have on the firm's use of HR practices, such as WFBs, that affect all employees, not just the executives.