bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tuning the Spin Coupling Interactions in the Nitroxide‐Based Bisphenol‐Like Diradicals
Authors: Song Meiyu , Song Xinyu , Bu Yuxiang 
Published: July 2017

AbstractThe intramolecular spin coupling interactions of bisphenol‐like trinary‐bridged diradicals [nitroxide‐(para/meta)phenylene‐X‐phenylene(para/meta)‐nitroxide, X=C=CH2, O, BH, NH and SO2] were explored with an emphasis on the tuning role of the X coupler at the (U)B3LYP/6‐311++G(d,p) level. Our results indicate that all designed trinary‐bridged diradicals featuring a V‐type structure with a bending angle of 104–130° and torsional angles of two phenylene rings being 20–90° exhibit different diradical character and magnetism, depending on the structures and properties of the X bridges. More interestingly, although meta/para‐phenylene supports a ferromagnetic (FM)/antiferromagnetic (AFM) coupling, their combinations by using X as a trinary bridge can mediate spin coupling, but the coupling magnitude strongly depends on X. In general, a para/para or meta/meta combination with X leads to an open‐shell singlet ground state and thus AFM, but the meta/meta combination considerably decreases the spin coupling interaction. In contrast, a para/meta combination with X produces a triplet ground state and FM. Their combination with a single‐electron conjugation end coupler (C=CH2) leads to an inverse coupling regularity. All results can be reasonably explained by the spin alternation rule, molecular structures, and properties. In particular, detailed spin coupling mechanisms are suggested to involve cooperative through‐space and through‐bond pathways with different levels of cooperativity. This is rationalized with the X‐induced bending of the diradicals not only modifying the through‐bond (extended π conjugation) pathway but also provididng a through‐space (face‐to‐face vs. side‐to‐side π–π interaction) possibility for spin coupling, in conjunction with twisting of the phenylene rings. Different contributions of the through‐space and through‐bond couplings are quantitatively distinguished and depend on the structure and property of the X coupler. Clearly, this work reports interesting aspects of the trinary bridged diradicals and also provides important information for the design of molecules for functional magnetic materials and tuning their magnetic properties.
Bifunctionalized Monomers for Surfaces with Controlled Hydrophobicity
Authors: Ben Trad Rawia , El Kout Emna , El Kateb Mejda , Beji Mohammed , Laugier Jean‐Pierre , Godeau Guilhem , Guittard Frédéric , Darmanin Thierry 
Published: July 2017

AbstractThe control of surface wettability is a key parameter for many application fields (materials, biomedical engineering, etc.). In this work, a new and efficient strategy to synthesize monomers suitable for hydrophobic surface elaboration is reported. This original approach allows the preparation of monomers and, as a consequence, surfaces bearing two different substituents by using the Staudinger reductive amination and amidification. Rough conducting polymer films were prepared by electropolymerization. The original surfaces reported here are highly structured surfaces with tunable hydrophobic features. Depending on the grafted chains, the surfaces are hydrophilic (PEDOT‐Benz‐Ph, θ=80 °; PEDOT=poly(3,4‐ethylenedioxythiophene)), hydrophobic (PEDOT‐Benz‐C12, θ=132 °), or even superhydrophobic (PEDOT‐Benz‐F8, θ=152 ° (α=5.0 °, H=0.3 °).
Hydrothermal Synthesis of ZnxNi1−xS Nanosheets for Hybrid Supercapacitor Applications
Authors: Mao Xiaoqing , Wang Weizhi , Wang Zhenghua 
Published: July 2017

AbstractNickel‐foam‐supported ZnxNi1−xS nanosheets are synthesized by a two‐step hydrothermal method. The ZnxNi1−xS nanosheets can be considered as the product of the partial substitution of Zn2+ ions by Ni2+ ions in the ZnS lattice. The resulting ZnxNi1−xS/Ni foam can be directly used as an electrode for supercapacitors. It can reach a specific capacitance of 1412 F g−1 at a current density of 1 Ag−1 with 68.0 % capacitance retention at 16 Ag−1. Control experiments show that the electrochemical performances of ZnxNi1−xS nanosheets are much better than those of ZnS and NiS prepared under the same conditions. Furthermore, a hybrid supercapacitor device was assembled by using the ZnxNi1−xS nanosheets as the positive electrode and porous carbon as the negative electrode; the device exhibited high power and energy densities. This study demonstrates that the construction of bimetal sulfides is a strategy to develop high‐performance supercapacitor electrode materials.
Fusing tree‐ring and forest inventory data to infer influences on tree growth
Authors: Evans Margaret E. K. , Falk Donald A. , Arizpe Alexis , Swetnam Tyson L. , Babst Flurin , Holsinger Kent E. 
Published: July 2017

AbstractBetter understanding and prediction of tree growth is important because of the many ecosystem services provided by forests and the uncertainty surrounding how forests will respond to anthropogenic climate change. With the ultimate goal of improving models of forest dynamics, here we construct a statistical model that combines complementary data sources, tree‐ring and forest inventory data. A Bayesian hierarchical model was used to gain inference on the effects of many factors on tree growth—individual tree size, climate, biophysical conditions, stand‐level competitive environment, tree‐level canopy status, and forest management treatments—using both diameter at breast height (dbh) and tree‐ring data. The model consists of two multiple regression models, one each for the two data sources, linked via a constant of proportionality between coefficients that are found in parallel in the two regressions. This model was applied to a data set of ~130 increment cores and ~500 repeat measurements of dbh at a single site in the Jemez Mountains of north‐central New Mexico,USA. The tree‐ring data serve as the only source of information on how annual growth responds to climate variation, whereas both data types inform non‐climatic effects on growth. Inferences from the model included positive effects on growth of seasonal precipitation, wetness index, and height ratio, and negative effects of dbh, seasonal temperature, southerly aspect and radiation, and plot basal area. Climatic effects inferred by the model were confirmed by a dendroclimatic analysis. Combining the two data sources substantially reduced uncertainty about non‐climate fixed effects on radial increments. This demonstrates that forest inventory data measured on many trees, combined with tree‐ring data developed for a small number of trees, can be used to quantify and parse multiple influences on absolute tree growth. We highlight the kinds of research questions that can be addressed by combining the high‐resolution information on climate effects contained in tree rings with the rich tree‐ and stand‐level information found in forest inventories, including projection of tree growth under future climate scenarios, carbon accounting, and investigation of management actions aimed at increasing forest resilience.
Detect and exploit hidden structure in fatty acid signature data
Authors: Bromaghin Jeffrey F. , Budge Suzanne M. , Thiemann Gregory W. 
Published: July 2017

AbstractEstimates of predator diet composition are essential to our understanding of their ecology. Although several methods of estimating diet are practiced, methods based on biomarkers have become increasingly common. Quantitative fatty acid signature analysis (QFASA) is a popular method that continues to be refined and extended. Quantitative fatty acid signature analysis is based on differences in the signatures of prey types, often species, which are recognized and designated by investigators. Similarly, predator signatures may be structured by known factors such as sex or age class, and the season or region of sample collection. The recognized structure in signature data inherently influences QFASA results in important and typically beneficial ways. However, predator and prey signatures may contain additional, hidden structure that investigators either choose not to incorporate into an analysis or of which they are unaware, being caused by unknown ecological mechanisms. Hidden structure also influences QFASA results, most often negatively. We developed a new method to explore signature data for hidden structure, called divisive magnetic clustering (DIMAC). Our DIMAC approach is based on the same distance measure used in diet estimation, closely linking methods of data exploration and parameter estimation, and it does not require data transformation or distributional assumptions, as do many multivariate ordination methods in common use. We investigated the potential benefits of the DIMAC method to detect and subsequently exploit hidden structure in signature data using two prey signature libraries with quite different characteristics. We found that the existence of hidden structure in prey signatures can increase the confusion between prey types and thereby reduce the accuracy and precision of QFASA diet estimates. Conversely, the detection and exploitation of hidden structure represent a potential opportunity to improve predator diet estimates and may lead to new insights into the ecology of either predator or prey. The DIMAC algorithm is implemented in the R diet estimation package qfasar.
The inflammatory cytokine interferon‐gamma inhibits sortilin‐1 expression in hepatocytes via the JAK/STAT pathway
Authors: Pirault John , Polyzos Konstantinos A. , Petri Marcelo H. , Ketelhuth Daniel F. J. , Bäck Magnus , Hansson Göran K. 
Published: July 2017

AbstractSortilin‐1, a receptor of the VPS10p family, has been associated with cardiovascular disease in genome‐wide association studies. It is implicated in lipoprotein metabolism, secretion of proprotein convertase subtilisin/kexin type 9 (PCSK9) and secretion of inflammatory cytokines. However, its own regulation remains unclear. Chronic inflammation is a hallmark of atherosclerosis and the absence of regulatory T (Treg) cells is associated with reduced protein expression of sortilin‐1 in the liver. Therefore, we postulated that mediator(s) of inflammation known to be downregulated by Treg cells may modulate sortilin‐1 expression. In this study, we identify interferon‐gamma (IFN‐γ) as the key inflammatory mediator controlling sortilin‐1 levels. In vitro cultures of murine hepatocytes cell line and in silico experiments showed that the transcription factor Signal transducer and activator of transcription 1 was activated and bound to the Sort‐1 gene upon IFN‐γ treatment. This reduced the expression of sortilin‐1, while disrupting the IFN‐γ signaling pathway prevented the effect. These data unravel an intricate mechanism by which inflammation modulates receptors involved in lipoprotein turnover.
IL‐33‐expanded human Vγ9Vδ2 T cells have anti‐lymphoma effect in a mouse tumor model
Authors: Duault Caroline , Betous Delphine , Bezombes Christine , Roga Stéphane , Cayrol Corinne , Girard Jean‐Philippe , Fournié Jean‐Jacques , Poupot Mary 
Published: July 2017

AbstractFrom several years, the anticancer effects of Vγ9 T lymphocytes make these cells good candidates for cancer immunotherapies. However, the proved efficacy of γδ Τ cell‐based cancer immunotherapies in some clinical trials was minimized due to the inherent toxicity of IL‐2, which is essential for the combination therapy with Phosphoantigen (PAg). Recently, we showed that IL‐33, a γ chain receptor‐independent cytokine, was able to induce the in vitro proliferation of PAg‐activated Vγ9 T cells, which were fully functional expressing IFN‐γ and TNF‐α and showing in vitro anti‐tumor cytotoxicity. We proposed IL‐33 as an alternative to IL‐2 for Vγ9 T cell‐based cancer immunotherapies, and have therefore evaluated the efficacy of this cytokine in preclinical investigations. This study shows that human Vγ9 T cells are able to proliferate in a mouse model with the combination of PAg and rhIL‐33, and that IL‐33‐expanded Vγ9 T cells can prevent tumor growth in a mouse lymphoma model.
Transient electroosmosis of a Maxwell fluid in a rotating microchannel
Authors: Kaushik Prasad , Mandal Shubhadeep , Chakraborty Suman 
Published: July 2017

AbstractThe transient electroosmotic flow of Maxwell fluid in a rotating microchannel is investigated both analytically and numerically. We bring out the complex dynamics of the flow during the transience due to the combination of rotation and rheological effects. We show the regimes of operation under which our analysis holds the most significance. We also shed some light on the volumetric flow rate characteristics as dictated by the underlying flow physics. Mainly we show and analyze the various regimes of operation under which viscoelastic effects actuated by electroosmotic forcing dominate over Coriolis forces and vice versa, which has not been studied before. We also observe that the analytical solution compares well with the numerical solution. We believe that the results from the present study could potentially have far reaching applications in bio‐fluidic microsystems where fluids such as blood, mucus and saliva may be involved.
The fractal properties of topography as controlled by the interactions of tectonic, lithological, and geomorphological processes
Authors: Liucci Luisa , Melelli Laura 
Published: July 2017

AbstractLandscape topography widely exhibits fractal structure. Because of the complexity of relief geometry this structure is not homogeneous in space, and the study of its spatial characteristics represents a powerful method for investigating the interrelationships between landforms and underlying processes. We explore these interrelationships using the digital elevation model (DEM) of an area located in central Italy, where landscape topography is strongly linked to its geological evolution, being characterized by alternating intermountain basins and mountain ranges trending NW–SE. A modified version of the method based on the standard deviation of relief elevations is used to evaluate the fractal parameters of relief after tiling the DEM in spatial units characterized by homogeneous fractal geometry, and statistical methods in conjunction with spatial analysis techniques are applied to the resulting terrain datasets. Both the lowest and (to a lesser extent) the highest values of fractal dimension are found to follow the ridge‐and‐valley trend. Low fractal dimension is observed in the mountain ranges characterized by massive strata of limestone, and along the fault scarps defining the contact between the intermountain basins and the surrounding slopes, where sediment deposition prevails. High fractal dimension is observed in regions characterized by highly erodible terrigenous lithology, and in areas where tectonic activity favors erosional processes mainly by rivers. The analysis of the (fractal) power law parameters also suggests that each major lithological complex has its own characteristic fractal signature. These results provide new insights into the link between the fractal properties of topography and the tectonic, lithological, and geomorphological features of the area, and show that the analysis approach proposed is useful to depict key aspects about the geomorphological and geological setting of an area, using only a DEM. Copyright © 2017 John Wiley & Sons, Ltd.
Characterization of OmcA Mutants from Shewanella oneidensis MR‐1 to Investigate the Molecular Mechanisms Underpinning Electron Transfer Across the Microbe‐Electrode Interface
Authors: Neto S. E. , de Melo‐Diogo D. , Correia I. J. , Paquete C. M. , Louro R. O. 
Published: July 2017

AbstractElectricity production in microbial fuel cells (MFCs) is an emerging green alternative to the use of fossil fuels. Shewanella oneidensis MR‐1 (SOMR‐1) is a Gram‐negative bacterium, adapted to MFCs due to its ability to link its bioenergetic metabolism through the periplasm to reduce extracellular electron acceptors. OmcA is a highly abundant outer‐membrane cytochrome of SOMR‐1 cells and is involved in the extracellular electron transfer to solid acceptors and electron shuttles. To investigate electron transfer performed by OmcA towards final acceptors, site directed mutagenesis was used to disturb the axial coordination of hemes. Interactions between OmcA and redox partners such as iron and graphene oxides, and electron shuttles were characterized using nuclear magnetic resonance and stopped‐flow experiments. Results showed that solid electron acceptors do not come into close proximity to the hemes, in agreement with experimentally observed slow electron transfer. In contrast, mutation of the distal axial ligand of heme VII changes the driving force of OmcA towards electron shuttles and reduces the affinity of the FMN:OmcA complex. Overall, these results reveal a functional specificity of particular hemes of OmcA and provide guidance for the rational design of mutated SOMR‐1 strains optimized for operating in different microbial electrochemical devices.
The relationship between vision impairment and well‐being among centenarians: findings from the Georgia Centenarian Study
Authors: Toyoshima Aya , Martin Peter , Sato Shinichi , Poon Leonard W. 
Published: July 2017

ObjectiveThe current study evaluated the visual function among centenarians and assessed the relationship between vision, social support, and well‐being.MethodsThis study used the data set of the Georgia Centenarian Study including 106 centenarians (18 men and 88 women). We used scores of the Snellen chart for objective vision and self‐reports for subjective vision. Social support, depression, and loneliness were also assessed.ResultsApproximately 75% of the centenarians showed some level of objective visual impairment, and 56% of them reported that they had visual impairment. Objective vision impairment was significantly related to depression. Multiple regression analysis revealed that both variables of visual function were significantly associated with depression, but not loneliness. In the model including depression, a significant interaction was obtained for social support and objective vision. Centenarians reported lower level of depression when they had social support. However, centenarians who had low level of visual function tended to report higher depression even if they had social support.ImplicationsThese results indicated that vision function was related to centenarians' well‐being, especially depression. Copyright © 2017 John Wiley & Sons, Ltd.
Analysis of the incidence and factors predictive of outcome in patients with head and neck cancer with pulmonary nodules
Authors: Green Richard , Macmillan Mark T. , Tikka Theofano , Bruce Lorna , Murchison John T. , Nixon Iain J. 
Published: July 2017

AbstractBackgroundThe management of pulmonary nodules is challenging; unfortunately, little is known about the incidence and significance of pulmonary nodules in patients with head and neck cancer.MethodsA review was conducted of 400 consecutive patients with head and neck cancer. Imaging was reviewed to identify the incidence of nodules and patient, tumor, and radiological factors associated with the risk of malignancy.ResultsNodules were found in 58% of patients, with a malignant rate of 6%. Age was the only predictor of having a nodule and advanced‐stage III + IV was a predictor of malignancy (P = .023; odds ratio [OR] 10.64; confidence interval 1.33‐84.98).ConclusionPatients presenting with head and neck cancer have a higher incidence of pulmonary nodules and a higher risk of malignancy. In contrast to the British Thoracic Society (BTS) guidelines, which use size to guide the need for serial scans, we would recommend follow‐up imaging in all patients with head and neck cancer with nodules, irrespective of size.
Effect of Chenopodium ambrosioides on the healing process of the in vivo bone tissue
Authors: Penha Elizandra Silva da , Lacerda‐Santos Rogério , Carvalho Maria Goretti Freire de , Oliveira Patrícia Teixeira de 
Published: July 2017

AbstractThe focus of this double‐blind randomized study was on evaluating the effect of an aqueous extract of Mastruz (Chenopodium ambrosioides L.) on the bone repair process in vivo. In total, 36 male Wistar rats were randomly selected for this study, and divided into 3 groups (n = 12): Group HS (Hemostatic Sponge), Group SM (Hemostatic Sponge with Mastruz) and Group BC (Blood Clot). In each animal, bone defects measuring 2 mm in diameter were performed in both tibias for placement of the substances. After 3 and 10 days, the animals were sacrificed, and the tissues were analyzed under an optical microscope relative to the following events: inflammatory infiltrate; necrosis; young fibroblasts; osteoclastic and osteoblastic activity; endosteal and periosteal bone formation; and bone repair. The results were assessed by using Kruskal–Wallis and Mann–Whitney tests (p < .05). Inflammatory infiltrate demonstrated difference between Groups SM and BC in the time interval of 3 days (p = .004); an event related to the presence of the fibrin sponge and liquid of the extract, which induced a foreign body initial reaction. The presence of young fibroblasts (p = .003), osteoclastic (p = .003), and osteoblastic (p = .020) activity was statistically significant between Groups HS and BC in the time interval of 10 days; performance was related to the presence of the sponge within bone. As regards injured bone tissue repair, Group SM demonstrated a higher level of regenerative capacity (p = 0.004), due to a larger quantities of endosteal and periosteal bone formation, demonstrated in Group SM. The aqueous extract of mastruz stimulated bone neoformation, presenting wound closure with bone tissue at the end of 10 days.
A mass spectrometry and DFT study of pyrithione complexes with transition metals in the gas phase
Authors: Butler Matias , Cabrera Gabriela M. 
Published: July 2017

Abstract2‐Mercaptopyridine N‐oxide (pyrithione, PTOH) along with several transition metal ions forms coordination compounds displaying notable biological activities. Gas‐phase complexes formed between pyrithione and manganese (II), cobalt (II), nickel (II), copper (II), and zinc (II) were investigated by infusion in the electrospray source of a quadrupole‐time of flight mass spectrometer. Remarkably, positive ion mode spectra displayed the singly charged metal adduct ion [C10H8MN2O2S2]2+ ([M(PTO)2]+• or [M(DPTO)]+•), where DPTO is dipyrithione, 2,2′‐dithiobis(pyridine N‐oxide), among the most abundant peaks, implying a change in the oxidation state of whether the metal ion or the ligands. In addition, doubly charged ions were recognized as metal adduct ions containing DPTO ligands, [M(DPTO)n]2+. Generation of [M(PTO)2]+• / [M(DPTO)]+• could be traced by CID of [M(DPTO)2]2+, by observation of the sequential losses of a charged (PTO+) and a radical (PTO•) deprotonated pyrithione ligand. The fragmentation pathways of [M(PTO)2]+• / [M(DPTO)]+• were compared among the different metal ions, and some common features were noticed. Density functional theory (DFT) calculations were employed to study the structures of the observed adduct ions, and especially, to decide in the adduct ion [M(PTO)2]+• / [M(DPTO)]+• whether the ligands are 2 deprotonated pyrithiones or a single dipyrithione as well as the oxidation state of the metal ion in the complex. Characterization of gas‐phase pyrithione metal ion complexes becomes important, especially taking into account the presence of a redox‐active ligand in the complexes, because redox state changes that produce new species can have a marked effect on the overall toxicological/biological response elicited by the metal system.