bluuebunny/crossref_metadata_2025 huggingface dataset:
Dielectric and thermal behaviors of fluorine‐containing dianhydride‐modified polybenzoxazine: A molecular design flexibility
Authors: Pattharasiriwong Patcharat , Jubsilp Chanchira , Mora Phattarin , Rimdusit Sarawut
Published: May 2017

Fluorine‐containing copolybenzoxazines were successfully prepared by reacting bisphenol‐AF/aniline‐based benzoxazine resin (BAF‐a) with 4,4′‐(hexafluoroisopropylidene) diphthalic anhydride (6FDA) in N,N‐dimethylacetamide solvent. The dielectric and thermal properties as well as flexibility of the resulting copolymer films were investigated. The incorporation of fluorine groups into polybenzoxazine was found to substantially decrease the dielectric constant of the resulting copolybenzoxazine to as low as 2.6. The formation of ester linkages between the hydroxyl groups in the poly(BAF‐a) and the carbonyl groups in the 6FDA resulted in substantially enhanced flexibility of the copolybenzoxazines. Moreover, the copolymers showed superior degradation temperature and significant improvement in char yield, up to 464 °C and 56%, respectively. The glass‐transition temperature of the copolybenzoxazines was increased with increasing dianhydride content and exhibited a maximum value of 290 °C at 2.5/1 mole ratio of poly(BAF‐a) to 6FDA. Therefore, the fluorine‐containing dianhydride‐modified polybenzoxazines are appropriate for applications as polymeric films for coatings and as a good electrical insulation material with high thermal resistance. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45204.
Visualization of stereoscopic anatomic models of the paranasal sinuses and cervical vertebrae from the surgical and procedural perspective
Authors: Chen Jian , Smith Andrew D. , Khan Majid A. , Sinning Allan R. , Conway Marianne L. , Cui Dongmei
Published: May 2017

Recent improvements in three‐dimensional (3D) virtual modeling software allows anatomists to generate high‐resolution, visually appealing, colored, anatomical 3D models from computed tomography (CT) images. In this study, high‐resolution CT images of a cadaver were used to develop clinically relevant anatomic models including facial skull, nasal cavity, septum, turbinates, paranasal sinuses, optic nerve, pituitary gland, carotid artery, cervical vertebrae, atlanto‐axial joint, cervical spinal cord, cervical nerve root, and vertebral artery that can be used to teach clinical trainees (students, residents, and fellows) approaches for trans‐sphenoidal pituitary surgery and cervical spine injection procedure. Volume, surface rendering and a new rendering technique, semi‐auto‐combined, were applied in the study. These models enable visualization, manipulation, and interaction on a computer and can be presented in a stereoscopic 3D virtual environment, which makes users feel as if they are inside the model. Anat Sci Educ 10: 598–606. © 2017 American Association of Anatomists.
A Computational Study of a Single‐Walled Carbon‐Nanotube‐Based Ultrafast High‐Capacity Aluminum Battery
Authors: Bhauriyal Preeti , Mahata Arup , Pathak Biswarup
Published: May 2017

Exploring suitable electrode materials is a fundamental step toward developing Al batteries with enhanced performance. In this work, we explore using density functional theory calculations the feasibility of single‐walled carbon nanotubes (SWNTs) as a cathode material for Al batteries. Carbon nanotubes with hollow structures and large surface area are able to overcome the difficulty of activating the opening of interlayer spaces as observed in graphite electrode during the first intercalation cycle. Our results show that AlCl4 binds strongly with the SWNT to result in an energetically and thermally stable AlCl4‐adsorbed SWNT system. Diffusion calculations show that the SWNT system allows ultrafast diffusion of AlCl4 with a more favorable inner surface diffusion than outer surface diffusion. Our charge‐density difference and Bader atomic charge analysis confirm the oxidation of SWNT upon adsorption of AlCl4, which shows a similar behavior to the previously studied graphite cathode. The average open‐circuit voltage and AlCl4 storage capacity increases with increasing SWNT diameter and can be as high as 1.96 V and 275 mA h g−1 in (25,25) SWNT relative to graphite (70 mA h g−1). All of these properties show that SWNTs are a potential cathode material for high‐performance Al batteries and should be explored further.
Nitrogen‐Doped Graphitic Porous Carbon Nanosheets Derived from In Situ Formed g‐C3N4 Templates for the Oxygen Reduction Reaction
Authors: Li Qi , Xu Dan , Ou Xu , Yan Feng
Published: May 2017

Heteroatom‐doped carbon materials have been considered as potential substitutes for Pt‐based electrocatalysts for the oxygen reduction reaction (ORR) in alkaline fuel cells. Here we report the synthesis of oxygen‐containing nitrogen‐doped carbon (ONC) nanosheets through the carbonization of a mixture that contained glucose and dicyandiamide (DCDA). In situ formed graphitic carbon nitride (g‐C3N4) derived from DCDA provided a nitrogen‐rich template, thereby facilitating the formation of ONC nanosheets. The resultant ONC materials with high nitrogen content, high specific surface areas, and highly mesoporous total volume displayed excellent electrochemical performance, including a similar ORR onset potential, half‐potential, a higher diffusion‐limited current, and excellent tolerance to methanol than that of the commercial Pt/C catalyst, respectively. Moreover, the ONC‐850 nanosheet displayed high long‐term durability even after 1000 cycles as well as a high electron transfer number of 3.92 (4.0 for Pt/C). Additionally, this work provides deeper insight into these materials and a versatile strategy for the synthesis of cost‐effective 2D N‐doped carbon electrocatalysts.
Monoubiquitination joins polyubiquitination as an esteemed proteasomal targeting signal
Authors: Livneh Ido , Kravtsova‐Ivantsiv Yelena , Braten Ori , Kwon Yong Tae , Ciechanover Aaron
Published: May 2017

A polyubiquitin chain attached covalently to the target substrate has been recognized for long as the “canonical” proteasomal degradation signal. However, several proteins have been shown to be targeted for degradation following monoubiquitination, indicating that the proteasome can recognize signals other than a ubiquitin polymer. A comprehensive screen aiming at determining the extent of this mode of recognition revealed that ∼40% of mammalian and ∼20% of yeast proteins are degraded following monoubiquitination. Characterization of these proteins showed that on average, the monoubiquitinated proteins are smaller than the polyubiquitinated ones, and in humans, are less disordered. Further, proteins degraded by the two different modes belong to distinct functional groups. These findings along with detailed structural analysis of the proteasome, its ubiquitin receptors and deubiquitinating enzymes, suggest that the ubiquitin signal – its formation, recognition, editing, and removal – is far more complex and diverse than originally assumed. Also see the video abstract here: https://youtu.be/QKpN9c6Rg20
Structural identification of degradants of moexipril by LC–MS/MS
Authors: Challa Purushotham Reddy , K. Ramakrishna , K. M. V. Narayana Rao
Published: May 2017

A gradient LC–MS method was developed for the identification and characterization of degradants of moexipril using liquid chromatography electrospray ionization tandem mass spectrometry (LC/ESI‐MS/MS). Moexipril was subjected to hydrolysis (acid, base and neutral), oxidation, photolytic and thermal degradation conditions as mentioned in ICH guidelines Q1A (R2). The drug degraded under hydrolysis, oxidation and photolytic conditions, but it was stable under thermal conditions. In total, five degradants were formed and separated on an Agilent XDB C‐18 column (4.6 × 150 mm, 5 μm) in a gradient elution method. Four degradants (D1, D2, D4 and D5) under acidic conditions, three degradants (D2, D3 and D4) under basic conditions and three degradants (D1, D4 and D5) under neutral and oxidative stress conditions were formed. In addition, two degradants (D4 and D5) were formed under photolytic stress conditions. To elucidate the structures of degradants, fragmentation of moexipril and its degradants was studied using LC–MS/MS experiments and accurate mass measurements (HRMS) data. The fragment ions in the product ion tandem mass spectra of all the degradants were compared with those of moexipril and assigned the probable structures for the degradants.
Suitability of selected chromatographic columns for analysis of fatty acids in dialyzed patients
Authors: Pazda Magdalena , Stepnowski Piotr , Sledzinski Tomasz , Chmielewski Michal , Mika Adriana
Published: May 2017

Gas chromatography–mass spectrometry is a preferred method for fatty acid (FA) analysis in biofluids from patients with metabolic diseases. Complex characteristics of FAs make their analysis particularly challenging. Selection of an appropriate chromatographic column is particularly important component of the process as it provides optimal separation and detection of possibly all FAs present in the sample. However, no accurate protocol for comparative evaluation of capillary columns for the analysis of whole serum FA profile in patients with chronic kidney disease (CKD) has been developed thus far. Therefore, in the present study four columns were examined to select the one providing optimal separation and determination of FA profiles in this group of patients. Moreover, serum FA profiles obtained with the selected column in CKD patients subjected to peritoneal dialysis and healthy controls were compared. Thirty‐seven component FAME Mix and sera from CKD patients were used to optimize chromatographic conditions and to select the most appropriate column. The ZB‐5 column turned out to be the most appropriate for the analysis of whole FA profile in CKD patients' sera. Then, this column was used to compare FA profiles in patients subjected to peritoneal dialysis and in healthy controls. The analysis demonstrated many abnormalities in the FA profile of CKD patients. Further studies involving larger groups of patients presenting with other stages of CKD are required to explain the impact of the disease progression on composition of serum FAs.
M2 macrophages induce EMT through the TGF‐β/Smad2 signaling pathway
Authors: Zhu Liangying , Fu Xiao , Chen Xiang , Han Xiaodong , Dong Ping
Published: May 2017

IPF is characterized by fibroblast accumulation, collagen deposition, and ECM remodeling, with myofibroblasts believed to be the effector cell type. Myofibroblasts develop due to EMT of lung alveolar epithelial cells, which can be induced by TGF‐β. M2 macrophages, a macrophage subpopulation, secrete large amounts of TGF‐β. To clarify the relationship between IPF, EMT, TGF‐β, and M2 macrophages, a bleomycin‐induced pulmonary fibrosis mouse model was used. Seventeen days after mice were treated with bleomycin, the successful establishment of a pulmonary fibrosis model was confirmed by HE stain and Masson's trichrome stain. We found evidence in support of EMT, such as elevated protein levels of α‐SMA in lung tissue and decreased levels of E‐cadherin and CK‐18. Additionally, increased TGF‐β levels and TGF‐β/Smad2 signaling activation was observed. Macrophages were recruited to pulmonary alveoli. Alveolar macrophages were phenotyped and identified as M2 macrophages, with up‐regulated CD206 on the cell surfaces. For in vitro studies, we treated RAW 264.7 cells with IL‐4 for 24 h, and the cells were then utilized as M2 macrophages. TGF‐β levels increased significantly in the culture supernatant. Forty‐eight hours after lung epithelial cells (MLE‐12) were co‐cultured with the M2 macrophages, the expression of α‐SMA increased, and E‐cadherin and CK‐18 decreased. When a TGF‐β receptor inhibitor, LY2109761 was used, the EMT induced by M2 macrophages was blocked. In conclusion, we demonstrated that M2 macrophages induce EMT through the TGF‐β/Smad2 signaling pathway.
Transcatheter interventions in adults with congenital heart disease: Surveys from the Society for Cardiovascular Angiography and Interventions to identify current patterns of care and perception on training requirements
Authors: Wadia Subeer K. , Accavitti Michael J. , Morgan Gareth J. , Kenny Damien , Hijazi Ziyad M. , Jones Thomas K. , Cabalka Allison K. , McElhinney Doff B. , Kavinsky Clifford J.
Published: May 2017

Background

Interventional catheterization is central to the care of Adults with Congenital Heart Disease (ACHD). Current standards for care provision and training in ACHD intervention are lacking. We sought to examine trends in current practice and training among interventionalists.

Methods

We analyzed the results of two separate international surveys in June 2016. One was sent to all active members from the Society of Cardiovascular Angiography and Interventions (SCAI) who self‐identified Structural Heart Disease or Congenital Heart Disease as a practice area. The second survey was conducted through the Pediatric Interventional Early Career Society (PICES) aimed at pediatric and adult congenital interventionalists in their first seven years after training. The total survey sample sizes were 1,535 and 112, respectively.

Results

Response rates for the SCAI and PICES surveys were 15% (237/1,535) and 75% (84/112), respectively. Most respondents (74%) worked at institutions with pediatric and adult facilities in proximity (major medical centers). While 75% of SCAI respondents believed complex transcatheter procedures should be performed by ACHD‐trained interventionalists or multidisciplinary teams, only 32% reported such care is being provided at the present time. Most pediatric and adult cardiologists surveyed (73%) do not believe current interventional fellowships provide adequate training for proficiency in ACHD interventions.

Conclusions

ACHD management remains underdeveloped in relative terms, particularly in the United States. Significant gaps in interventional standards of practice and future training needs were recognized by this study. Our survey should serve as an impetus to establish training guidelines for physicians who seek to perform ACHD interventions.
Quasi‐Steady‐State Polarization Reveals the Interplay of Capacitive and Faradaic Processes in Capacitive Deionization
Authors: Holubowitch Nicolas , Omosebi Ayokunle , Gao Xin , Landon James , Liu Kunlei
Published: May 2017

We employ slow cyclic voltammetry to study the quasi‐steady‐state capacitive deionization (CDI) of aerated 10 mM NaCl from Vcell=−0.2 to 2 V. The method allows for the deconvolution of capacitive and faradaic processes, which are significant even at low voltage, in conjunction with pH, conductivity, dissolved oxygen (DO), and electrode potential measurements. The pH at three locations and effluent DO data identify asymmetric electrosorption in the cell configured with pristine activated carbon electrodes, where charge is irreversibly consumed to produce H+/OH− instead of reversibly adsorbing Cl−/Na+. Implementing a reference electrode resolves ion adsorption as a function of the individual potential at each electrode. Near‐electrode pH probes reveal pH environments that diverge by up to 8 units during cell polarization and allow more accurate calculation of faradaic redox potentials in a flow‐by CDI cell. In the aerated NaCl solution that will be relevant to industrial‐scale water treatment, we find that DO reduction occurs to a greater degree than Na+ adsorption at the cathode until DO removal becomes mass transfer limited at <−0.2 V vs. SHE. Two cell architectures – flow‐by and flow‐through – corroborate our findings. Finally, we reconcile all measurements to generate a map displaying how the potential is partitioned amongst the capacitive and faradaic processes occurring during CDI operation over a 2.2 V window.
Electrochemical Performance of Cobalt‐Free Nb and Ta Co‐Doped Perovskite Cathodes for Intermediate‐Temperature Solid Oxide Fuel Cells
Authors: Liang Fengli , Wang Zaixing , Wang Zhuoran , Mao Junkui , Sunarso Jaka
Published: May 2017

This work characterizes a series of Ta and Nb co‐doped cobalt‐free perovskite oxides with the compositions of SrNb0.2‐xTaxFe0.8O3‐δ (x=0, 0.05, 0.1, 0.15, and 0.2) for intermediate‐temperature solid oxide fuel cell (IT‐SOFC) applications. Their electronic conductivities displayed semiconducting behavior (i. e. increase with temperature rise) between 300 and 500 °C and metallic behavior (i. e. decrease with temperature rise) from 500 to 900 °C. SrNb0.1Ta0.1Fe0.8O3–δ provided the highest electrical conductivity that reaches 300 S cm−1 at 500 °C. The thermal expansion coefficients for SrNb0.2‐xTaxFe0.8O3–δ were lower than those reported for cobalt‐containing perovskite cathodes. They varied from 12.83×10−6 to 16.31×10−6 K−1 between 30 and 810 °C. Among the five tested cathodes, SrNb0.1Ta0.1Fe0.8O3–δ exhibited the lowest area‐specific resistance between 550 and 750 °C, with a minimum of 0.046 Ω cm2 at 750 °C, when tested in its symmetric cell configuration of cathode|Sm0.2Ce0.8O1.9 (SDC)|cathode. A peak power density of 1223 mW cm−2 was achieved on a SrNb0.1Ta0.1Fe0.8O3‐δ|SDC|yttria‐stabilized zirconia (YSZ)|Ni‐YSZ anode‐supported fuel cell at 700 °C. This work highlights the opportunity to create new perovskite cathode compositions with improved electrochemical performance through a co‐doping strategy.
Using the Lewis Acid Me3Si−F−Al(ORF)3 To Prepare Phosphino‐Phosphonium Cations with the Least‐Coordinating Anion [(RFO)3Al−F−Al(ORF)3]−
Authors: Possart Josephine , Martens Arthur , Schleep Mario , Ripp Alexander , Scherer Harald , Kratzert Daniel , Krossing Ingo
Published: May 2017

By reaction of two equivalents of Me3Si−F−Al(ORF)3 1 with an equimolar amount of PPh2Cl, the salt [Ph2P−PPh2Cl]+[(RFO)3Al−F−Al(ORF)3]− 2 is prepared smoothly in 91 % yield (NMR, XRD). The synthesis of [Ph2P−PPh3]+[(RFO)3Al−F−Al(ORF)3]− 3 is best achieved by a two‐step reaction: first, two equivalents of 1 react with one PPh3 to give [Me3Si−PPh3]+[(RFO)3Al−F−Al(ORF)3]− 4 (NMR, XRD), which, upon reaction with PPh2Cl, yields pure 3 and Me3SiCl (NMR, XRD). Typically, a stoichiometry of two equivalents of 1 with respect to one equivalent of the chloride donor should be used. Otherwise, the residual strong Lewis acidity of the [(RFO)3Al−F−Al(ORF)3]− anion in the presence of the [F−Al(ORF)3]− anion—that forms with less than two equivalents of 1—leads to further chloride exchange reactions that complicate work‐up. This route presents the easiest way to introduce the least‐coordinating [(RFO)3Al−F−Al(ORF)3]− anion into a system. We expect a wide use of this route in all areas, in which chloride‐bond heterolysis in combination with very weakly coordinating anions is desirable. Additionally, we performed calculations on the bond dissociation mechanisms of [R2P−PMe3]+ and the isoelectronic Me2P−SiMe3 and Me2Si−PMe3 in dependence of the solvent permittivity. These calculations show, especially for the neutral reference compounds, a heavy influence of the solvent on the dissociation mechanism, which is why we suggest investigating these properties in solution instead of gas phase.
Influence of the Substrate/Inoculum Ratio on Process Stability and Performance during Batch Digestion of Grass Silage
Authors: Benito Patricia C. , Greger Manfred
Published: May 2017

The impact of the substrate/inoculum ratio on the performance and process stability during batch digestion of grass silage, an important substrate in biogas plants, was investigated. The methane yield, degradability, and evolution of intermediary products were monitored in mesophilic reactors fed with increasing amounts of grass silage. A first‐order kinetics model was also applied. Signs of inhibition were observed for the highest loadings, but the system recovered and process failure was not observed. The methane yield decreased with increasing loading but the system was resilient to high loadings under batch conditions.
Facile Synthesis of Nitrogen‐Doped Graphene Aerogels for Electrode Materials in Supercapacitors
Authors: Zhang Yong , Zhu Jiayi , Ren Hongbo , Bi Yutie , Zhang Lin
Published: May 2017

Three‐dimensional porous nitrogen‐doped graphene aerogels (NGAs) were synthesized by using graphene oxide (GO) and chitosan (CS) via a self‐assembly process by one‐pot hydrothermal method. The morphology and structure of the as‐prepared materials were characterized by means of scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, XPS spectroscopy, Raman spectroscopy, nitrogen adsorption/desorption measurement and Fourier transform infrared spectroscopy. The electrochemical performance of NGAs was studied by cyclic voltammetry, galvanostatic charge/discharge and impedance spectroscopy measurements. The microstructure, surface area and capacitance of NGAs could be facilely controlled by adding different amounts of chitosan. The prepared NGA‐4 showed a specific capacitance of 148.0 F/g at the discharge current density of 0.5 A/g and also retained 95.3% of the initial capacitance after 5000 cycles at the scan rate of 10 mV/s. It provided a possible way to obtain graphene based materials with high surface area and capacitance.
A LoCATe‐based visual place recognition system for mobile robotics and GPGPUs
Authors: Bampis Loukas , Chatzichristofis Savvas , Iakovidou Chryssanthi , Amanatiadis Angelos , Boutalis Yiannis , Gasteratos Antonios
Published: May 2017

In this paper, a novel visual Place Recognition approach is evaluated based on a visual vocabulary of the Color and Edge Directivity Descriptor (CEDD) to address the loop closure detection task. Even though CEDD was initially designed so as to globally describe the color and texture information of an input image addressing Image Indexing and Retrieval tasks, its scalability on characterizing single feature points has already been proven. Thus, instead of using CEDD as a global descriptor, we adopt a bottom‐up approach and use its localized version, Local Color And Texture dEscriptor, as an input to a state‐of‐the‐art visual Place Recognition technique based on Visual Word Vectors. Also, we use a parallel execution pipeline based on a previous work of ours using the well established General Purpose Graphics Processing Unit (GPGPU) computing. Our experiments show that the usage of CEDD as a local descriptor produces high accuracy visual Place Recognition results, while the parallelization used allows for a real‐time implementation even in the case of a low‐cost mobile device.
Nitrogen Fixation by Gliding Arc Plasma: Better Insight by Chemical Kinetics Modelling
Authors: Wang Weizong , Patil Bhaskar , Heijkers Stjin , Hessel Volker , Bogaerts Annemie
Published: May 2017

Invited for this month's cover is the group of Prof. Dr. Annemie Bogaerts at the University of Antwerp and their collaborators at Eindhoven University of Technology in the laboratory of Prof. Dr. Volker Hessel. The cover image shows that gliding arc plasma leads to energy efficient nitrogen fixation by promoting the vibrational excitation of N2. The Full Paper itself is available at 10.1002/cssc.201700095.
New insights into the genetic composition and phylogenetic relationship of wolves and dogs in the Iberian Peninsula
Authors: Pires Ana Elisabete , Amorim Isabel R. , Borges Carla , Simões Fernanda , Teixeira Tatiana , Quaresma Andreia , Petrucci‐Fonseca Francisco , Matos José
Published: May 2017

This study investigates the gene pool of Portuguese autochthonous dog breeds and their wild counterpart, the Iberian wolf subspecies (Canis lupus signatus), using standard molecular markers. A combination of paternal and maternal molecular markers was used to investigate the genetic composition, genetic differentiation and genetic relationship of native Portuguese dogs and the Iberian wolf. A total of 196 unrelated dogs, including breed and village dogs from Portugal, and other dogs from Spain and North Africa, and 56 Iberian wolves (wild and captive) were analyzed for nuclear markers, namely Y chromosome SNPs, Y chromosome STR loci, autosomal STR loci, and a mitochondrial fragment of the control region I. Our data reveal new variants for the molecular markers and confirm significant genetic differentiation between Iberian wolf and native domestic dogs from Portugal. Based on our sampling, no signs of recent introgression between the two subspecies were detected. Y chromosome data do not reveal genetic differentiation among the analyzed dog breeds, suggesting they share the same patrilineal origin. Moreover, the genetic distinctiveness of the Iberian wolf from other wolf populations is further confirmed with the description of new mtDNA variants for this endemism. Our research also discloses new molecular markers for wolf and dog subspecies assignment, which might become particularly relevant in the case of forensic or noninvasive genetic studies. The Iberian wolf represents a relic of the once widespread wolf population in Europe and our study reveals that it is a reservoir of unique genetic diversity of the grey wolf, Canis lupus. These results stress the need for conservation plans that will guarantee the sustainability of this threatened top predator in Iberia.
Tracking a single pigeon using a shadowing filter algorithm
Authors: Zaitouny Ayham , Stemler Thomas , Small Michael
Published: May 2017

Miniature GPS devices now allow for measurement of the movement of animals in real time and provide high‐ quality and high‐resolution data. While these new data sets are a great improvement, one still encounters some measurement errors as well as device failures. Moreover, these devices only measure position and require further reconstruction techniques to extract the full dynamical state space with the velocity and acceleration. Direct differentiation of position is generally not adequate. We report on the successful implementation of a shadowing filter algorithm that (1) minimizes measurement errors and (2) reconstructs at the same time the full phase‐space from a position recording of a flying pigeon. This filter is based on a very simple assumption that the pigeon's dynamics are Newtonian. We explore not only how to choose the filter's parameters but also demonstrate its improvements over other techniques and give minimum data requirements. In contrast to competing filters, the shadowing filter's approach has not been widely implemented for practical problems. This article addresses these practicalities and provides a prototype for such application.
Couch potatoes do better: Delayed dispersal and territory size affect the duration of territory occupancy in a monogamous mammal
Authors: Mayer Martin , Zedrosser Andreas , Rosell Frank
Published: May 2017

In territorial, socially monogamous species, the establishment and defense of a territory are an important strategy to maximize individual fitness, but the factors responsible for the duration of territory occupancy are rarely studied, especially in long‐lived mammals. A long‐term monitoring program in southeast Norway spanning over 18 years allowed us to follow the individual life histories of Eurasian beavers (Castor fiber) from adolescence in their natal family group to dispersal and territory establishment until the end of territory occupancy. We investigated whether territory size, resource availability, population density, and dispersal age could explain the duration of territory occupancy, which ranged from 1 to 11 years. The duration of territory occupancy was positively related to dispersal age, suggesting that individuals that delayed dispersal had a competitive advantage due to a larger body mass. This is in support with the maturation hypothesis, which states that an animal should await its physical and behavioral maturation before the acquisition of a territory. Further, we found that individuals that established in medium‐sized territories occupied them longer as compared to individuals in small or large territories. This suggests that large territories are more costly to defend due to an increased patrolling effort, and small territories might not have sufficient resources. The lifetime reproductive success ranged from zero to six kits and generally increased with an increasing duration of territory occupancy. Our findings show the importance of holding a territory and demonstrate that dispersal decisions and territory selection have important consequences for the fitness of an individual.
Global realized niche divergence in the African clawed frog Xenopus laevis
Authors: Rödder Dennis , Ihlow Flora , Courant Julien , Secondi Jean , Herrel Anthony , Rebelo Rui , Measey G. J. , Lillo Francesco , De Villiers F. A. , De Busschere Charlotte , Backeljau Thierry
Published: May 2017

Although of crucial importance for invasion biology and impact assessments of climate change, it remains widely unknown how species cope with and adapt to environmental conditions beyond their currently realized climatic niches (i.e., those climatic conditions existing populations are exposed to). The African clawed frog Xenopus laevis, native to southern Africa, has established numerous invasive populations on multiple continents making it a pertinent model organism to study environmental niche dynamics. In this study, we assess whether the realized niches of the invasive populations in Europe, South, and North America represent subsets of the species’ realized niche in its native distributional range or if niche shifts are traceable. If shifts are traceable, we ask whether the realized niches of invasive populations still contain signatures of the niche of source populations what could indicate local adaptations. Univariate comparisons among bioclimatic conditions at native and invaded ranges revealed the invasive populations to be nested within the variable range of the native population. However, at the same time, invasive populations are well differentiated in multidimensional niche space as quantified via n‐dimensional hypervolumes. The most deviant invasive population are those from Europe. Our results suggest varying degrees of realized niche shifts, which are mainly driven by temperature related variables. The crosswise projection of the hypervolumes that were trained in invaded ranges revealed the south‐western Cape region as likely area of origin for all invasive populations, which is largely congruent with DNA sequence data and suggests a gradual exploration of novel climate space in invasive populations.
Driving factors and temporal fluctuation of Collembola communities and reproductive mode across forest types and regions
Authors: Pollierer Melanie M. , Scheu Stefan
Published: May 2017

Despite the major role of Collembola in forest soil animal food webs, ecological and evolutionary determinants of their community composition are not well understood. We investigated abundance, community structure, life forms, and reproductive mode of Collembola in four different forest types (coniferous, young managed beech, old managed beech, and unmanaged beech forests) representing different management intensities. Forest types were replicated within three regions across Germany: the Schorfheide‐Chorin, the Hainich, and the Swabian Alb, differing in geology, altitude, and climate. To account for temporal variation, samples were taken twice with an interval of 3 years. To identify driving factors of Collembola community structure, we applied structural equation modeling, including an index of forest management intensity, abiotic and biotic factors such aspH, C‐to‐N ratio of leaf litter, microbial biomass, and fungal‐to‐bacterial ratio. Collembola abundance, biomass, and community composition differed markedly between years, with most pronounced differences in the Schorfheide, the region with the harshest climatic conditions. There, temporal fluctuations of parthenogenetic Collembola were significantly higher than in the other regions. In the year with the more favorable conditions, parthenogenetic species flourished, with their abundance depending mainly on abiotic, density‐independent factors. This is in line with the “Structured Resource Theory of Sexual Reproduction,” stating that parthenogenetic species are favored if density‐independent factors, such as desiccation, frost or flooding, prevail. In contrast, sexual species in the same year were mainly influenced by resource quality‐related factors such as the fungal‐to‐bacterial ratio and the C‐to‐N ratio of leaf litter. The influence of forest management intensity on abundances was low, indicating that disturbance through forest management plays a minor role. Accordingly, differences in community composition were more pronounced between regions than between different forest types, pointing to the importance of regional factors.
Monitoring for Adaptive Management or Modernity: Lessons from recent initiatives for holistic environmental management
Authors: Waylen Kerry A. , Blackstock Kirsty L.
Published: May 2017

Recommendations for improving environmental management often advocate a holistic approach that supports both social and environmental objectives. This should be reflected in approaches to monitoring and evaluation; however, monitoring is often inadequate and hence limits our ability to implement adaptive management. It is important to understand if monitoring practices are changing, and if not, why. Thus, this paper considers the monitoring practices and priorities of 24 ‘Ecosystem Approach’ projects implementing holistic and participatory environmental management. We found project monitoring was often focused on biophysical indicators, such as indicators of water pollution, even when adaptive management might prioritize understanding different issues or using different data‐types. By contrast, aspects of social and economic aspects were monitored infrequently. Procedural aspects were rarely tracked. Project managers' aspirations did sometimes include such issues, but these were seen as more difficult or even impossible to measure. Schema were also shaped by the need to demonstrate accountability and quantify progress to funders. Our study suggests monitoring still falls short of theoretical recommendations. This is partially due to the misfit between new understandings of socio‐ecological systems and pre‐existing modernist paradigms, whose conceptions and expectations still have pervasive effects of our ways of thinking and working. Tackling this requires explicit attention to sticking points across the levels of institutions that shape environmental management. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment
Halogen Bonds Involved in Copper(I) Complexes: A Study Based on the Electronic Charge Density
Authors: Piltan Mohammad , Farshadfar Kaveh , Roe S. Mark
Published: May 2017

This communication describes the crystal structures of CuI complexes and their topological analysis with an emphasis on the Laplacian of the electron density to investigate the characteristics of halogen bonding. To gain insight into the halogen bonds (XBs), we survey wavefunction and DFT methods. The different XBs, that is, Cl···Cl–, I···I–, Br···N3–, and I···SCN–, in the crystal packing of these compounds are categorized as a combination of a region of charge depletion and a region of charge concentration in the valence‐shell charge concentration or hole–lump interactions. The full quantum potential based lump–hole concept is more useful than the σ‐hole concept, in which the electrostatic portion of the potential is merely considered. Such a view of halogen bonding can rationalize the geometry around the XBs. The noncovalent interaction reduced density gradient (NCI‐RDG) approach was applied to the real‐space visualization and quantitative investigation of the XBs as well.
Transformation of Chlorohydrocarbons and Amines in the Coordination Sphere of [(µ‐H)2Os3(CO)10]
Authors: Afonin M. Yu. , Savkov B. Yu. , Virovets A. V. , Korenev V. S. , Golovin A. V. , Maksakov V. A.
Published: May 2017

A reaction has been found and investigated that demonstrates the potential for coordination, activation, and transformation of three organic molecules, namely, two dichloromethane molecules and one amine molecule, in the coordination sphere of the [(µ‐H)Os3(CO)10]– carbonylate anion, which is formed in situ from the deprotonation of [(µ‐H)2Os3(CO)10]. This reaction is very intricate and comprises such steps as the nucleophilic substitution of chloride ions by cluster carbonylate anions in the halocarbons, C–H, C–N, and C–Cl bond cleavage, and C–C and C–N bond formation under unusually mild conditions for such reactions leading to the formation of the CH=CH2‐ or CH=CHNR2‐bearing complexes [(µ‐Cl)Os3(µ2‐σ,π‐CH=CH2)(CO)10] and [(µ‐H)Os3(µ‐CH=CHNR2)(CO)10]. The reaction is sensitive to the nature of the halogen in the halocarbon. When bromine or iodine was used in place of chlorine in the halohydrocarbons, [(µ‐H)Os3(µ‐X)(CO)10] (X = Br, I) clusters were obtained in good yields, which apparently indicates the replacement of the SN2 mechanism by SN2Hal.
Direct estimation of the spontaneous mutation rate by short-term mutation accumulation lines inChironomus riparius
Authors: Oppold Ann-Marie , Pfenninger Markus
Published: May 2017

Mutations are the ultimate basis of evolution, yet their occurrence rate is known only for few species. We directly estimated the spontaneous mutation rate and the mutational spectrum in the nonbiting midge C. riparius with a new approach. Individuals from ten mutation accumulation lines over five generations were deep genome sequenced to count de novo mutations that were not present in a pool of F1 individuals, representing parental genotypes. We identified 51 new single site mutations of which 25 were insertions or deletions and 26 single nucleotide mutations. This shift in the mutational spectrum compared to other organisms was explained by the high A/T content of the species. We estimated a haploid mutation rate of 2.1 × 10−9 (95% confidence interval: 1.4 × 10−9 – 3.1 × 10-9) that is in the range of recent estimates for other insects and supports the drift barrier hypothesis. We show that accurate mutation rate estimation from a high number of observed mutations is feasible with moderate effort even for nonmodel species.
Nanoporous UHMWPE Membrane Separators for Safer and High‐Power‐Density Rechargeable Batteries
Authors: Li Runlai , Gao Ping
Published: May 2017

Battery safety has been of critical concerns and there are renewed interest in developing safer membranes for enhancing the inherent safety of lithium ion batteries. In this paper, the synthesis of a robust and safer self‐reinforced composite ultrahigh molecular weight polyethylene (UHMWPE) membrane is described. The self‐reinforced composite membrane consists of ≈200 nm nanopores homogeneously embedded inside interpenetrating nanofibrillar “shish kebab” networks. It performs thermal fuse function by selectively melting its kebab crystals while the elongated shish fibrillary backbones remain intact. Simulated thermal fuse function tests show that the newly prepared separator displays a 300% increase in tensile strength (550 MPa), 300% increase in puncture resistance (1.5 N μm−1), as well as an 18 000 times increase in impedance when lateral dimensions are kept constant. Cells prepared using the UHMWPE separators also exhibit a 10% higher energy density and better cyclability than those using commercial separators. Hence, the newly prepared ultrathin and dimensionally stable membrane will enhance the safety protections for rechargeable batteries with low impedance for high energy and power density.
Optical coherence elastography for strain dynamics measurements in laser correction of cornea shape
Authors: Zaitsev Vladimir Y. , Matveyev Alexander L. , Matveev Lev A. , Gelikonov Grigory V. , Omelchenko Alexander I. , Baum Olga I. , Avetisov Sergey E. , Bolshunov Andrey V. , Siplivy Vladimir I. , Shabanov Dmitry V. , Vitkin Alex , Sobol Emil N.
Published: May 2017

We describe the use of elastographic processing in phase‐sensitive optical coherence tomography (OCT) for visualizing dynamics of strain and tissue‐shape changes during laser‐induced photothermal corneal reshaping, for applications in the emerging field of non‐destructive and non‐ablative (non‐LASIK) laser vision correction. The proposed phase‐processing approach based on fairly sparse data acquisition enabled rapid data processing and near‐real‐time visualization of dynamic strains. The approach avoids conventional phase unwrapping, yet allows for mapping strains even for significantly supra‐wavelength inter‐frame displacements of scatterers accompanied by multiple phase‐wrapping. These developments bode well for real‐time feedback systems for controlling the dynamics of corneal deformation with 10–100 ms temporal resolution, and for suitably long‐term monitoring of resultant reshaping of the cornea. In ex‐vivo experiments with excised rabbit eyes, we demonstrate temporal plastification of cornea that allows shape changes relevant for vision‐correction applications without affecting its transparency. We demonstrate OCT's ability to detect achieving of threshold temperatures required for tissue plastification and simultaneously characterize transient and cumulative strain distributions, surface displacements, and scattering tissue properties. Comparison with previously used methods for studying laser‐induced reshaping of cartilaginous tissues and numerical simulations is performed.
Bone Loss at the Hip and Subsequent Mortality in Older Men: The Osteoporotic Fractures in Men (MrOS) Study
Authors: Cawthon Peggy M , Patel Sheena , Ewing Susan K , Lui Li‐Yung , Cauley Jane A , Lyons Jennifer G , Fredman Lisa , Kado Deborah M , Hoffman Andrew R , Lane Nancy E , Ensrud Kristine E , Cummings Steven R , Orwoll Eric S ,   for the Osteoporotic Fractures in Men (MrOS) Study Research Group
Published: May 2017

Low bone mineral density (BMD) is associated with increased mortality risk, yet the impact of BMD loss on mortality is relatively unknown. We hypothesized that greater BMD loss is associated with increased mortality risk in older men. Change in femoral neck BMD was assessed in 4400 Osteoporotic Fractures in Men (MrOS) study participants with two to three repeat dual‐energy X‐ray absorptiometry scans over an average of 4.6 ± 0.4 (mean ± SD) years. Change in femoral neck BMD was estimated using mixed effects models; men were grouped into three categories of BMD change: maintenance (n = 1087; change ≥ 0 g/cm2); expected loss (n = 2768; change between 0 g/cm2 and <1 SD below mean change [>–0.034 g/cm2]); and accelerated loss (n = 545; change 1 SD below mean change or worse [≤–0.034 g/cm2]). Multivariate proportional hazards models adjusted for potential confounders estimated the risk of all‐cause mortality over 8.1 ± 2.8 years following visit 2. Mortality was centrally adjudicated by physician review of death certificates. At visit 1, mean age was 72.9 ± 5.5 years. Men who maintained BMD were less likely to die during the subsequent follow‐up period (33.7%) than men who had accelerated BMD loss (60.6%) (p < 0.001). Compared to men who had maintained BMD, those who had accelerated BMD loss had a 44% greater risk of mortality in multivariate‐adjusted models (HR, 1.44; 95% CI, 1.23 to 1.68). Compared to men who had maintained BMD, there was no significant difference in mortality risk for men with expected loss of BMD (36.9% died) (multivariate HR, 1.00; 95% CI, 0.89 to 1.13). Further adjustment for visit 1 or visit 2 BMD measurement did not substantially alter these associations. Results for total hip BMD were similar. In conclusion, accelerated loss of BMD at the hip is a risk factor for mortality in men that is not explained by comorbidity burden, concurrent change in weight, or physical activity. © 2017 The Authors. JBMR Plus is published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.
Emotion Reactivity, Comfort Expressing Emotions, and Future Suicidal Ideation in Emerging Adults
Authors: Polanco‐Roman Lillian , Moore Alyssa , Tsypes Aliona , Jacobson Colleen , Miranda Regina
Published: May 2017

Objective

Emotion reactivity and difficulties in expressing emotions have been implicated in risk for suicidal behavior. This study examined comfort in expressing emotions (positive vs. negative) and depressive symptoms as mediators of the prospective relation between emotion reactivity and suicidal ideation.

Design

Emerging adults (N = 143; 72% female; 28% White) completed measures of emotion reactivity, comfort expressing emotions, and suicidal ideation at baseline and of depressive symptoms and suicidal ideation 12 months later.

Results

Emotion reactivity predicted suicidal ideation at follow‐up through depressive symptoms. Difficulty expressing love–but not happiness, sadness, and anger–partially mediated the relationship between emotion reactivity and suicidal ideation at follow‐up before but not after adjusting for baseline ideation.

Conclusion

The relation between high emotion reactivity and suicidal ideation may be explained by discomfort in the expression of positive emotions and by depressive symptoms. Promotion of comfort in positive emotion expression may reduce vulnerability to suicidal ideation.
Beta‐hydroxy‐beta‐methylbutyrate supplementation and skeletal muscle in healthy and muscle‐wasting conditions
Authors: Holeček Milan
Published: May 2017

Beta‐hydroxy‐beta‐methylbutyrate (HMB) is a metabolite of the essential amino acid leucine that has been reported to have anabolic effects on protein metabolism. The aims of this article were to summarize the results of studies of the effects of HMB on skeletal muscle and to examine the evidence for the rationale to use HMB as a nutritional supplement to exert beneficial effects on muscle mass and function in various conditions of health and disease.

The data presented here indicate that the beneficial effects of HMB have been well characterized in strength‐power and endurance exercise. HMB attenuates exercise‐induced muscle damage and enhances muscle hypertrophy and strength, aerobic performance, resistance to fatigue, and regenerative capacity. HMB is particularly effective in untrained individuals who are exposed to strenuous exercise and in trained individuals who are exposed to periods of high physical stress. The low effectiveness of HMB in strength‐trained athletes could be due to the suppression of the proteolysis that is induced by the adaptation to training, which may blunt the effects of HMB. Studies performed with older people have demonstrated that HMB can attenuate the development of sarcopenia in elderly subjects and that the optimal effects of HMB on muscle growth and strength occur when it is combined with exercise. Studies performed under in vitro conditions and in various animal models suggest that HMB may be effective in treatment of muscle wasting in various forms of cachexia. However, there are few clinical reports of the effects of HMB on muscle wasting in cachexia; in addition, most of these studies evaluated the therapeutic potential of combinations of various agents. Therefore, it has not been possible to determine whether HMB was effective or if there was a synergistic effect. Although most of the endogenous HMB is produced in the liver, there are no reports regarding the levels and the effects of HMB supplementation in subjects with liver disease. Several studies have suggested that anabolic effects of HMB supplementation on skeletal muscle do not occur in healthy, non‐exercising subjects.

It is concluded that (i) HMB may be applied to enhance increases in the mass and strength of skeletal muscles in subjects who exercise and in the elderly and (ii) studies examining the effects of HMB administered alone are needed to obtain conclusions regarding the specific effectiveness in attenuating muscle wasting in various muscle‐wasting disorders.
Change of left ventricular “rigid body rotation” during dipyridamole‐induced vasodilation: A case from the three‐dimensional speckle tracking echocardiographic MAGYAR‐Stress Study
Authors: Nemes Attila , Szántó Gyula , Domsik Péter , Kormányos Árpád , Kalapos Anita , Ambrus Nóra , Forster Tamás
Published: May 2017

A patient with previous coronary stenting presented with stable angina and positive exercise treadmill test. Echocardiography with three‐dimensional speckle‐tracking demonstrated left ventricular rigid body rotation (near absence of left ventricular twist), whose characteristics changed dramatically during dipyridamole‐induced vasodilatation. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46:152–156, 2018