bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of captivity on the skin microbial symbionts in threeAtelopusspecies from the lowlands of Colombia and Ecuador
Authors: Flechas Sandra V. , Blasco-Zúñiga Ailin , Merino-Viteri Andrés , Ramírez-Castañeda Valeria , Rivera Miryan , Amézquita Adolfo
Published: July 2017

Many amphibian species are at risk of extinction in their natural habitats due to the presence of the fungal pathogenBatrachochytrium dendrobatidis(Bd). For the most highly endangered species,captive assurance colonies have been established as an emergency measure to avoid extinction. Experimental research has suggested that symbiotic microorganisms in the skin of amphibians play a key role againstBd. While previous studies have addressed the effects of captivity on the cutaneous bacterial community, it remains poorly studied whether and how captive conditions affect the proportion of beneficial bacteria or their anti-Bdperformance on amphibian hosts. In this study we sampled three amphibian species of the highly threatened genus,Atelopus, that remain in the wild but are also part ofex situbreeding programs in Colombia and Ecuador. Our goals were to (1) estimate the diversity of culturable bacterial assemblages in these three species ofAtelopus, (2) describe the effect of captivity on the composition of skin microbiota, and (3) examine how captivity affects the bacterial ability to inhibitBdgrowth. Using challenge assays we tested each bacterial isolate againstBd, and through sequencing of the 16S rRNA gene, we identified species from thirteen genera of bacteria that inhibitedBdgrowth. Surprisingly, we did not detect a reduction in skin bacteria diversity in captive frogs. Moreover, we found that frogs in captivity still harbor bacteria with anti-Bdactivity. Although the scope of our study is limited to a few species and to the culturable portion of the bacterial community, our results indicate that captive programs do not necessarily change bacterial communities of the toad skins in a way that impedes the control ofBdin case of an eventual reintroduction.
Maxent-directed field surveys identify new populations of narrowly endemic habitat specialists
Authors: Rhoden Cody M. , Peterman William E. , Taylor Christopher A.
Published: July 2017

Background

Rare or narrowly endemic organisms are difficult to monitor and conserve when their total distribution and habitat preferences are incompletely known. One method employed in determining distributions of these organisms is species distribution modeling (SDM).

Methods

Using two species of narrowly endemic burrowing crayfish species as our study organisms, we sought to ground validate Maxent, a commonly used program to conduct SDMs. We used fine scale (30 m) resolution rasters of pertinent habitat variables collected from historical museum records in 2014. We then ground validated the Maxent model in 2015 by randomly and equally sampling the output from the model.

Results

The Maxent models for both species of crayfish showed positive relationships between predicted relative occurrence rate and crayfish burrow abundance in both a Receiver Operating Characteristic and generalized linear model approach. The ground validation of Maxent led us to new populations and range extensions of both species of crayfish.

Discussion

We conclude that Maxent is a suitable tool for the discovery of new populations of narrowly endemic, rare habitat specialists and our technique may be used for other rare, endemic organisms.
Laminarin protects against hydrogen peroxide-induced oxidative damage in MRC-5 cells possibly via regulating NRF2
Authors: Liu Xue , Liu Huaman , Zhai Yi , Li Yan , Zhu Xue , Zhang Wei
Published: July 2017

Oxidative damage is a major cause of lung diseases, including pulmonary fibrosis. Laminarin is a kind of polysaccharide extracted from brown algae and plays vital roles in various biological processes. However, the functions and mechanisms of laminarin in pulmonary oxidative damage are poorly understood. This study aimed at investigating the protective effect of laminarin against pulmonary oxidative damage and underlying mechanisms. Human lung fibroblasts MRC-5 cells were treated with hydrogen peroxide to induce oxidative damage. Laminarin treatment was performed before or after hydrogen peroxide treatment, and then major indexes of oxidative damage, including superoxide dismutase (SOD), malondialdehyde (MDA), reduced glutathione (GSH) and catalase (CAT), were quantified by biochemical assays. The expression of oxidation-related factor, nuclear factor erythroid 2 like 2 (NRF2) was analyzed by qPCR, Western blot and immunofluorescence assay. NRF2 knockdown and overexpression were performed by cell transfection to reveal possible mechanisms. Results showed that laminarin treatment of 0.020 mg/mL for 24 h, especially the pre-treatment, could significantly relieve changes in SOD, MDA, GSH and CAT that were altered by hydrogen peroxide, and promote NRF2 mRNA (P < 0.001). NRF2 protein was also elevated by laminarin, and nuclear translocation was observed. Factors in NRF2 signaling pathways, including KEAP1, NQO1, GCLC and HO1, were all regulated by laminarin. Roles of NRF2 were tested, suggesting that NRF2 regulated the concentration of SOD, MDA, GSH and CAT, suppressed KEAP1, and promoted NQO1, GCLC and HO1. These findings suggested the protective role of laminarin against pulmonary oxidative damage, which might involve the regulation of NRF2 signaling pathways. This study provided information for the clinical application of laminarin to pulmonary diseases like pulmonary fibrosis.
The competition between coastal trace metal fluxes and oceanic mixing from the 10Be/9Be ratio: Implications for sedimentary records
Authors: Wittmann H. , von Blanckenburg F. , Mohtadi M. , Christl M. , Bernhardt A.
Published: July 2017

At an ocean margin site 37°S offshore Chile, we use the meteoric cosmogenic 10Be/9Be ratio to trace changes in terrestrial particulate composition due to exchange with seawater. We analyzed the marine authigenic phase in surface sediments along a coast‐perpendicular transect and compared to samples from their riverine source. We find evidence for growth of authigenic rims through coprecipitation, not via reversible adsorption, that incorporate an open ocean 10Be/9Be signature from a deep water source only 30 km from the coast, overprinting terrestrial 10Be/9Be signatures. Together with increasing 10Be/9Be ratios, particulate‐bound Fe concentrations increase, which we attribute to release of Fe‐rich pore waters during boundary exchange in the sediment. The implications for the use of 10Be/9Be in sedimentary records for paleodenudation flux reconstructions are the following: in coast‐proximal sites the authigenic record will likely preserve local riverine ratios unaffected by exchange with seawater, whereas sites beneath well‐mixed seawater will preserve global flux signatures.
Toluene, ethylbenzene and phenol – Determination of o‐cresol, m‐cresol, 2‐ethylphenol, 4‐ethylphenol and phenol in urine using gas chromatography‐mass spectrometry [Biomonitoring Methods, 2011]
Authors: Schettgen T. , Alt A. , Dewes P.
Published: July 2017

The article contains sections titled:

General principles

Equipment, chemicals and solutions

Equipment

Chemicals

Solutions

Internal standard

Calibration standards

Specimen collection and sample preparation

Sample preparation for the determination of cresols and ethylphenols

Sample preparation for the determination of phenol

Operational parameters

Gas chromatography

Mass spectrometry

Analytical determination

Calibration

Calculation of the analytical results

Standardisation and quality control

Evaluation of the method

Precision

Accuracy

Absolute recovery

Detection limits and quantitation limits

Sources of error

Discussion of the method
Origin of Hysteresis in CH3NH3PbI3 Perovskite Thin Films
Authors: Seol Daehee , Jeong Ahreum , Han Man Hyung , Seo Seongrok , Yoo Tae Sup , Choi Woo Seok , Jung Hyun Suk , Shin Hyunjung , Kim Yunseok
Published: July 2017

Organic–inorganic hybrid perovskite solar cells are attracting the attention of researchers owing to the high level of performance they exhibit in photovoltaic device applications. However, the attainment of an even higher level of performance is hindered by their anomalous current–voltage (I–V) hysteresis behavior. Even though experimental and theoretical studies have suggested that the perovskite materials may have a ferroelectric nature, it is still far from being fully understood. In this study, the origin of the hysteresis behavior in CH3NH3PbI3 perovskite thin films is investigated. The behavior of ferroelectricity using piezoresponse force microscopy is first examined. Then, by comparing the scan‐rate‐dependent nano/macroscopic I–V curves, it is found that ion migration assisted by the grain boundaries is a dominant origin of I–V hysteresis from a macroscopic viewpoint. Consequently, the observations suggest that, even though ferroelectricity exists in the CH3NH3PbI3 perovskite materials, ion migration primarily contributes to the macroscopic I–V hysteresis. The presented results can provide fundamental guidelines to the resolution of hysteresis issues in organic–inorganic hybrid perovskite materials.
Disordered Topography Mediates Filopodial Extension and Morphology of Cells on Stiff Materials
Authors: Yang Lei , Gong Ze , Lin Yuan , Chinthapenta Viswanath , Li Qunyang , Webster Thomas J. , Sheldon Brian W.
Published: July 2017

In cell–material interactions, cells use filopodia to sense external biochemical and mechanical cues, and subsequently dictate their survival. In an effort toward understanding how disordered topography of stiff materials influences filopodial recognition, diamond films with grain sizes varying from nano‐ to micrometers are fabricated for the investigation of osteoblast filopodial extension. Interestingly, straight filopodia with pronounced cell–substrate adhesion are observed on a nanocrystalline diamond (NCD) region, whereas filopodia on a microcrystalline diamond (MCD) surface only adhere to, and get deflected by, large diamond grains. More importantly, filopodia on NCD keep propagating with a constant velocity, whereas the same process takes place in a slow and intermittent manner on MCD. A theoretical model is also developed and it suggests that the contact between the disordered topography and the filopodial tip plays a key role in altering filopodial growth dynamics. In particular, it is predicted that large surface asperities can block the movement of the filopodial tip, delay its extension, and cause bending of the structure, in quantitative agreement with experimental observations. These findings reveal previously underappreciated effects of random, stiff topographies on the response of cells, and hence can provide new insights for the design of future implant biomaterials.
Retracted: 3D Printing of Bilineage Constructive Biomaterials for Bone and Cartilage Regeneration
Authors: Deng Cuijun , Yao Qingqiang , Feng Chun , Li Jiayi , Wang Liming , Cheng Guofeng , Shi Mengchao , Chen Lei , Chang Jiang , Wu Chengtie
Published: July 2017

Owing to the different biological properties of articular cartilage and subchondral bone, it remains significant challenge to construct a bi‐lineage constructive scaffold. In this study, manganese (Mn)‐doped β‐TCP (Mn‐TCP) scaffolds with varied Mn contents are prepared by a 3D‐printing technology. The effects of Mn on the physicochemical properties, bioactivity, and corresponding mechanism for stimulating osteochondral regeneration are systematically investigated. The incorporation of Mn into β‐TCP lowers the lattices parameters and crystallization temperatures, but improves the scaffold density and compressive strength. The ionic products from Mn‐TCP significantly improve the proliferation of both rabbit chondrocytes and mesenchymal stem cells (rBMSCs), as well as promote the differentiation of chondrocytes and rBMSCs. The in vivo study shows that Mn‐TCP scaffolds distinctly improve the regeneration of subchondral bone and cartilage tissues as compared to TCP scaffolds, upon transplantation in rabbit osteochondral defects for 8 and 12 weeks. The mechanism is closely related to the Mn2+ ions significantly stimulated the proliferation and differentiation of chondrocytes through activating HIF pathway and protected chondrocytes from the inflammatory osteoarthritis environment by activating autophagy. These findings suggest that 3D‐printing of Mn‐containing scaffolds with improved physicochemical properties and bilineage bioactivities represents an intelligent strategy for regenerating osteochondral defects.
Supercapacitive Iontronic Nanofabric Sensing
Authors: Li Ruya , Si Yang , Zhu Zijie , Guo Yaojun , Zhang Yingjie , Pan Ning , Sun Gang , Pan Tingrui
Published: July 2017

The study of wearable devices has become a popular research topic recently, where high‐sensitivity, noise proof sensing mechanisms with long‐term wearability play critical roles in a real‐world implementation, while the existing mechanical sensing technologies (i.e., resistive, capacitive, or piezoelectric) have yet offered a satisfactory solution to address them all. Here, we successfully introduced a flexible supercapacitive sensing modality to all‐fabric materials for wearable pressure and force sensing using an elastic ionic–electronic interface. Notably, an electrospun ionic fabric utilizing nanofibrous structures offers an extraordinarily high pressure‐to‐capacitance sensitivity (114 nF kPa−1), which is at least 1000 times higher than any existing capacitive sensors and one order of magnitude higher than the previously reported ionic devices, with a pressure resolution of 2.4 Pa, achieving high levels of noise immunity and signal stability for wearable applications. In addition, its fabrication process is fully compatible with existing industrial manufacturing and can lead to cost‐effective production for its utility in emerging wearable uses in a foreseeable future.
Controlled Pinning of Conjugated Polymer Spherulites and Its Application in Detectors
Authors: Dörling Bernhard , Sánchez‐Díaz Antonio , Arteaga Oriol , Veciana Andrea , Alonso Maria Isabel , Campoy‐Quiles Mariano
Published: July 2017

The nucleation of single macroscopic spherulites at desired positions, as well as ordered arrays of multiple spherulites, is demonstrated by combining the use of crystallizable solvents with local control of solvent evaporation during solution deposition. Moreover, the temperature assisted localized frustration of molecular orientation is shown, enabling the fabrication of samples containing both isotropic areas and spherulites. These macroscopic circular polycrystalline structures are characterized using a range of polarized spectroscopic techniques that allow quantifying their large degree of chain orientation. In order to show the potential of these large conjugated polymer spherulites centered at desired locations, graded bilayer organic photovoltaic devices were fabricated to be used as polarimeters, solid state light polarization detectors with no moving parts, and position sensitive photodetectors.
Self‐Assembled Luminescent Quantum Dots To Generate Full‐Color and White Circularly Polarized Light
Authors: Huo Shengwei , Duan Pengfei , Jiao Tifeng , Peng Qiuming , Liu Minghua
Published: July 2017

The design and fabrication of quantum dots (QDs) with circularly polarized luminescence (CPL) has been a great challenge in developing chiroptical materials. We herein propose an alternative to the use of chiral capping reagents on QDs for the fabrication of CPL‐active QDs that is based on the supramolecular self‐assembly of achiral QDs with chiral gelators. Full‐color‐tunable CPL‐active QDs were obtained by simple mixing or gelation of a chiral gelator and achiral 3‐mercaptopropionic acid capped QDs. In addition, the handedness of the CPL can be controlled by the supramolecular chirality of the gels. Moreover, QDs with circularly polarized white light emission were fabricated for the first time by tuning the blending ratio of colorful QDs in the gel. The chirality transfer in the co‐assembly of the achiral QDs with the gelator and the spacer effect of the capping reagents on the QD surface are also discussed. This work provides new insight into the design of functional chiroptical materials.
Multiple Metal–Metal Bond or No Bond? The Electronic Structure of V2O2
Authors: Hübner Olaf , Himmel Hans‐Jörg
Published: July 2017

Detailed knowledge of the electronic structure of vanadium oxide clusters provides the basis for understanding and tuning their significant catalytic properties. However, already for the simple four‐atom V2O2 molecule, there are contradictory reports in the literature regarding the electronic ground state and a possible vanadium–vanadium bond. We herein show through a combination of experimental (matrix isolation) studies and theoretical results that there is a multiple vanadium–vanadium bond in this benchmark vanadium oxide molecule.
Model Free Adaptive Control for a Class of Nonlinear Systems Using Quantized Information
Authors: Bu Xuhui , Qiao Yingxu , Hou Zhongsheng , Yang Junqi
Published: July 2017

This paper considers the stability of model free adaptive control systems with quantized information. Two quantized model free adaptive control (QMFAC) algorithms are proposed by using different signal quantization schemes, and here the logarithmic quantizer is introduced to decode these signals with a number of quantization levels. By using the sector bound method, the stability conditions of proposed QMFAC algorithms can be given and the effect of quantization error for such systems can also be discussed. It is shown that the tracking error under the QMFAC algorithm with system output quantized signal is proved to converge to a bound, and the bound depending on quantization density and desired trajectory. Thus, the tracking error under the QMFAC algorithm with tracking error quantized signal converges to zero. Two illustrative examples are given to validate the theoretical results.
Thyroid Medication Use and Birth Defects in the National Birth Defects Prevention Study
Authors: Howley Meredith M. , Fisher Sarah C. , Van Zutphen Alissa R. , Waller Dorothy K. , Carmichael Suzan L. , Browne Marilyn L. ,   The National Birth Defects Prevention Study
Published: July 2017

Background

Thyroid disorders are common among reproductive‐aged women, with hypothyroidism affecting 2 to 3% of pregnancies, and hyperthyroidism affecting an additional 0.1 to 1%. We examined associations between thyroid medications and individual birth defects using data from the National Birth Defects Prevention Study (NBDPS).

Methods

The NBDPS is a multisite, population‐based, case–control study that included pregnancies with estimated delivery dates from 1997 to 2011. We analyzed self‐reported thyroid medication use from mothers of 31,409 birth defect cases and 11,536 unaffected controls. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression for birth defects with five or more exposed cases, controlling for maternal age, race/ethnicity, and study center. Crude ORs and exact 95% CIs were estimated for defects with 3 to 4 exposed cases.

Results

Thyroid hormone was used by 738 (2.3%) case and 237 (2.1%) control mothers, and was associated with anencephaly (OR = 1.68; 95% CI, 1.03–2.73), holoprosencephaly (OR = 2.48; 95% CI, 1.13–5.44), hydrocephaly (1.77; 95% CI, 1.07–2.95) and small intestinal atresia (OR = 1.81; 95% CI, 1.04–3.15). Anti‐thyroid medication was used by 34 (0.1%) case and 10 (<0.1%) control mothers, and was associated with aortic valve stenosis (OR = 6.91; 95% CI, 1.21–27.0).

Conclusion

While new associations were identified, our findings are relatively consistent with previous NBDPS analyses. Our findings suggest thyroid medication use is not associated with most birth defects studied in the NBDPS, but may be associated with some specific birth defects. These results should not be interpreted to suggest that medications used to treat thyroid disease are teratogens, as the observed associations may reflect effects of the underlying thyroid disease. Birth Defects Research 109:1471–1481, 2017.© 2017 Wiley Periodicals, Inc.
A Rapid Screening of Ligand Binding by Measuring Intrinsic Fluorescence Changes of Proteins
Authors: Nguyen Tien Duc , Jeong Kwangjun , Ryu Juyeon , Jung Che‐Hun
Published: July 2017

High‐throughput analysis of genomic and proteomic information lead to large numbers of target molecules. The bottlenecks are generally subsequent verification steps, which require development of efficient screening tools. Protein–protein and protein–ligand interactions constitute the basis of most biological processes in living organisms. In general, proteins are labeled with fluorescent dyes to enhance sensitivities and the fluorescence changes are widely utilized for determining protein–protein and protein–ligand bindings. This study is to demonstrate that the intrinsic fluorescence of proteins by tryptophan and tyrosine and its change accompanied by ligand binding is sufficiently sensitive for studying protein–ligand interactions. Malate dehydrogenase catalyzes inter‐conversion of oxaloacetate and NADH to malate and NAD+, respectively. Malate did not change the fluorescence of malate dehydrogenase. But, the dissociation constants (KD) for NADH and NAD+ could be measured by fluorescence changes and they are comparable to KM determined by enzyme kinetics. The high KD (1.5 mM) for oxaloacetate agreed well with the ordered Bi Bi mechanism of malate dehydrogenase, in which NADH bound first and generated a binding site for oxaloacetate. The dissociation constant for cyclic di‐GMP to malate dehydrogenase was also determined by fluorescence changes and it was comparable to that collected from computational molecular docking analysis. The KD for cyclic di‐GMP to methionine aminopeptidase, glycerol dehydrogenase, and peptidase B could also be determined by intrinsic fluorescence changes as 58, 58, 52 μM, respectively. These results suggest that the intrinsic fluorescence of proteins by tryptophan and tyrosine is sensitive enough to determine protein–ligand interactions. It provides a label‐free, quick‐and‐easy tool for screening the ligands to proteins.
Tailoring the Sodium Storage Performance of Carbon Nanowires by Microstructure Design and Surface Modification with N, O and S Heteroatoms
Authors: Qiao Yun , Ma Mengyue , Liu Yang , Han Ruimin , Cheng Xiaoguang , Li Qingling , Li Xiangnan , Dong Hongyu , Yin Yanhong , Yang Shuting
Published: July 2017

The electronic environment and physicochemical property of carbon materials can be easily tailored and modulated by heteroatom doping. Herein, we demonstrate that net‐like N, O, S triple‐doped microporous carbon nanowires (NOS‐MCNs) as an anode can be designed to improve the electrochemical performance of sodium ion batteries. Ammonium persulfate as oxidant can also provide a nitrogen and sulfur source for S‐containing PPy. The N, O and S atoms are introduced into the carbon skeleton with activation and carbonization processes to modify the surface properties. As an anode, the material exhibits a high specific capacity and a long lifespan (≈301 mA h g−1 at 0.2 A g−1 after 1000 cycles) as well as an excellent rate capability (158 mA h g−1 at an extremely high current density of 10 A g−1). This work offers a facile strategy to synthesize triple‐doped porous carbon materials for sodium ion batteries and other energy‐storage fields.
What is a “unimodal” cell population? Using statistical tests as criteria for unimodality in automated gating and quality control
Authors: Johnsson Kerstin , Linderoth Magnus , Fontes Magnus
Published: July 2017

Many automated gating algorithms for flow cytometry data are based on the concept of unimodal cell populations. However, in this article, we show that criteria previously used to make decisions on unimodality cannot adequately distinguish unimodal from bimodal densities. We show that dip and bandwidth tests for unimodality, taken from the statistics literature, can do this with consistent and low error rates. These tests also have the possibility to adjust the significance level to handle the trade‐off between failing to detect a second mode and seeing a second mode when there is none. The differences between the dip and bandwidth tests are elucidated using real data from the FlowCAP I challenge, also guidelines for flow cytometry data preprocessing are given. © 2017 International Society for Advancement of Cytometry
Sharing is caring? Measurement error and the issues arising from combining 3D morphometric datasets
Authors: Fruciano Carmelo , Celik Mélina A. , Butler Kaylene , Dooley Tom , Weisbecker Vera , Phillips Matthew J.
Published: July 2017

Geometric morphometrics is routinely used in ecology and evolution and morphometric datasets are increasingly shared among researchers, allowing for more comprehensive studies and higher statistical power (as a consequence of increased sample size). However, sharing of morphometric data opens up the question of how much nonbiologically relevant variation (i.e., measurement error) is introduced in the resulting datasets and how this variation affects analyses. We perform a set of analyses based on an empirical 3D geometric morphometric dataset. In particular, we quantify the amount of error associated with combining data from multiple devices and digitized by multiple operators and test for the presence of bias. We also extend these analyses to a dataset obtained with a recently developed automated method, which does not require human‐digitized landmarks. Further, we analyze how measurement error affects estimates of phylogenetic signal and how its effect compares with the effect of phylogenetic uncertainty. We show that measurement error can be substantial when combining surface models produced by different devices and even more among landmarks digitized by different operators. We also document the presence of small, but significant, amounts of nonrandom error (i.e., bias). Measurement error is heavily reduced by excluding landmarks that are difficult to digitize. The automated method we tested had low levels of error, if used in combination with a procedure for dimensionality reduction. Estimates of phylogenetic signal can be more affected by measurement error than by phylogenetic uncertainty. Our results generally highlight the importance of landmark choice and the usefulness of estimating measurement error. Further, measurement error may limit comparisons of estimates of phylogenetic signal across studies if these have been performed using different devices or by different operators. Finally, we also show how widely held assumptions do not always hold true, particularly that measurement error affects inference more at a shallower phylogenetic scale and that automated methods perform worse than human digitization.
Making the most of survey data: Incorporating age uncertainty when fitting growth parameters
Authors: Spence Michael A. , Turtle Alan J.
Published: July 2017

Individual growth is an important parameter and is linked to a number of other biological processes. It is commonly modeled using the von Bertalanffy growth function (VBGF), which is regularly fitted to age data where the ages of the animals are not known exactly but are binned into yearly age groups, such as fish survey data. Current methods of fitting the VBGF to these data treat all the binned ages as the actual ages. We present a new VBGF model that combines data from multiple surveys and allows the actual age of an animal to be inferred. By fitting to survey data for Atlantic herring (Clupea harengus) and Atlantic cod (Gadus morhua), we compare our model with two other ways of combining data from multiple surveys but where the ages are as reported in the survey data. We use the fitted parameters as inputs into a yield‐per‐recruit model to see what would happen to advice given to management. We found that each of the ways of combining the data leads to different parameter estimates for the VBGF and advice for policymakers. Our model fitted to the data better than either of the other models and also reduced the uncertainty in the parameter estimates and models used to inform management. Our model is a robust way of fitting the VBGF and can be used to combine data from multiple sources. The model is general enough to fit other growth curves for any taxon when the age of individuals is binned into groups.
Marine dock pilings foster diverse, native cryptobenthic fish assemblages across bioregions
Authors: Brandl Simon J. , Casey Jordan M. , Knowlton Nancy , Duffy James Emmett
Published: July 2017

Anthropogenic habitats are increasingly prevalent in coastal marine environments. Previous research on sessile epifauna suggests that artificial habitats act as a refuge for nonindigenous species, which results in highly homogenous communities across locations. However, vertebrate assemblages that live in association with artificial habitats are poorly understood. Here, we quantify the biodiversity of small, cryptic (henceforth “cryptobenthic”) fishes from marine dock pilings across six locations over 35° of latitude from Maine to Panama. We also compare assemblages from dock pilings to natural habitats in the two southernmost locations (Panama and Belize). Our results suggest that the biodiversity patterns of cryptobenthic fishes from dock pilings follow a Latitudinal Diversity Gradient (LDG), with average local and regional diversity declining sharply with increasing latitude. Furthermore, a strong correlation between community composition and spatial distance suggests distinct regional assemblages of cryptobenthic fishes. Cryptobenthic fish assemblages from dock pilings in Belize and Panama were less diverse and had lower densities than nearby reef habitats. However, dock pilings harbored almost exclusively native species, including two species of conservation concern absent from nearby natural habitats. Our results suggest that, in contrast to sessile epifaunal assemblages on artificial substrates, artificial marine habitats can harbor diverse, regionally characteristic assemblages of vertebrates that follow macroecological patterns that are well documented for natural habitats. We therefore posit that, although dock pilings cannot function as a replacement for natural habitats, dock pilings may provide cost‐effective means to preserve native vertebrate biodiversity, and provide a habitat that can be relatively easily monitored to track the status and trends of fish biodiversity in highly urbanized coastal marine environments.
Socio‐economic, scientific, and political benefits of mycotourism
Authors: Büntgen Ulf , Latorre Joaquin , Egli Simon , Martínez‐Peña Fernando
Published: July 2017

Rural areas particularly suffer from economic crises where they overlap with long‐term negative effects of climate change. Here, we introduce the concept of mycotourism by means of mushroom‐related industries in central‐northeastern Spain. We describe how this novel branch of eco‐tourism can help stabilize social and political structures. Likewise, we illuminate the potential of mycotourism to compensate for some losses related to widespread unemployment and summer drought, as well as to generate unexpectedly fruitful research opportunities. Focussing on Spain's emerging black truffle industry, we recommend a stronger involvement of natural sciences, conservation services, and management strategies in commercial endeavors. We emphasize the relevance of direct and indirect climatic impacts on ecological and societal systems as well as on economic markets. Moreover, we stress the importance of a vital science–policy interface at various scales, with immediate opportunities for sustainable landscape protection and the preservation of biological diversity.
Nitrogen‐induced terrestrial eutrophication: cascading effects and impacts on ecosystem services
Authors: Clark Christopher M. , Bell Michael D. , Boyd James W. , Compton Jana E. , Davidson Eric A. , Davis Christine , Fenn Mark E. , Geiser Linda , Jones Laurence , Blett Tamara F.
Published: July 2017

Human activity has significantly increased the deposition of nitrogen (N) on terrestrial ecosystems over pre‐industrial levels leading to a multitude of effects including losses of biodiversity, changes in ecosystem functioning, and impacts on human well‐being. It is challenging to explicitly link the level of deposition on an ecosystem to the cascade of ecological effects triggered and ecosystem services affected, because of the multitude of possible pathways in the N cascade. To address this challenge, we report on the activities of an expert workshop to synthesize information on N‐induced terrestrial eutrophication from the published literature and to link critical load exceedances with human beneficiaries by using the STressor–Ecological Production function–final ecosystem Services Framework and the Final Ecosystem Goods and Services Classification System (FEGS‐CS). We found 21 N critical loads were triggered by N deposition (ranging from 2 to 39 kg N·ha−1·yr−1), which cascaded to distinct beneficiary types through 582 individual pathways in the five ecoregions examined (Eastern Temperate Forests, Marine West Coast Forests, Northwestern Forested Mountains, North American Deserts, Mediterranean California). These exceedances ultimately affected 66 FEGS across a range of final ecosystem service categories (21 categories, e.g., changes in timber production, fire regimes, and native plant and animal communities) and 198 regional human beneficiaries of different types. Several different biological indicators were triggered in different ecosystems, including grasses and/or forbs (33% of all pathways), mycorrhizal communities (22%), tree species (21%), and lichen biodiversity (11%). Ecoregions with higher deposition rates for longer periods tended to have more numerous and varied ecological impacts (e.g., Eastern Temperate Forests, eight biological indicators) as opposed to other ecoregions (e.g., North American Deserts and Marine West Coast Forests each with one biological indicator). Nonetheless, although ecoregions differed by ecological effects from terrestrial eutrophication, the number of FEGS and beneficiaries impacted was similar across ecoregions. We found that terrestrial eutrophication affected all ecosystems examined, demonstrating the widespread nature of terrestrial eutrophication nationally. These results highlight which people and ecosystems are most affected according to present knowledge, and identify key uncertainties and knowledge gaps to be filled by future research.
Detecting population–environmental interactions with mismatched time series data
Authors: Ferguson Jake M. , Reichert Brian E. , Fletcher Robert J. , Jager Henriëtte I.
Published: July 2017

Time series analysis is an essential method for decomposing the influences of density and exogenous factors such as weather and climate on population regulation. However, there has been little work focused on understanding how well commonly collected data can reconstruct the effects of environmental factors on population dynamics. We show that, analogous to similar scale issues in spatial data analysis, coarsely sampled temporal data can fail to detect covariate effects when interactions occur on timescales that are fast relative to the survey period. We propose a method for modeling mismatched time series data that couples high‐resolution environmental data to low‐resolution abundance data. We illustrate our approach with simulations and by applying it to Florida's southern Snail kite population. Our simulation results show that our method can reliably detect linear environmental effects and that detecting nonlinear effects requires high‐resolution covariate data even when the population turnover rate is slow. In the Snail kite analysis, our approach performed among the best in a suite of previously used environmental covariates explaining Snail kite dynamics and was able to detect a potential phenological shift in the environmental dependence of Snail kites. Our work provides a statistical framework for reliably detecting population–environment interactions from coarsely surveyed time series. An important implication of this work is that the low predictability of animal population growth by weather variables found in previous studies may be due, in part, to how these data are utilized as covariates.
Composition and structure of porcine digital flexor tendon‐bone insertion tissues
Authors: Chandrasekaran Sandhya , Pankow Mark , Peters Kara , Huang Hsiao‐Ying Shadow
Published: July 2017

Tendon‐bone insertion is a functionally graded tissue, transitioning from 200 MPa tensile modulus at the tendon end to 20 GPa tensile modulus at the bone, across just a few hundred micrometers. In this study, we examine the porcine digital flexor tendon insertion tissue to provide a quantitative description of its collagen orientation and mineral concentration by using Fast Fourier Transform (FFT) based image analysis and mass spectrometry, respectively. Histological results revealed uniformity in global collagen orientation at all depths, indicative of mechanical anisotropy, although at mid‐depth, the highest fiber density, least amount of dispersion, and least cellular circularity were evident. Collagen orientation distribution obtained through 2D FFT of histological imaging data from fluorescent microscopy agreed with past measurements based on polarized light microscopy. Results revealed global fiber orientation across the tendon‐bone insertion to be preserved along direction of physiologic tension. Gradation in the fiber distribution orientation index across the insertion was reflective of a decrease in anisotropy from the tendon to the bone. We provided elemental maps across the fibrocartilage for its organic and inorganic constituents through time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS). The apatite intensity distribution from the tendon to bone was shown to follow a linear trend, supporting past results based on Raman microprobe analysis. The merit of this study lies in the image‐based simplified approach to fiber distribution quantification and in the high spatial resolution of the compositional analysis. In conjunction with the mechanical properties of the insertion tissue, fiber, and mineral distribution results for the insertion from this may potentially be incorporated into the development of a structural constitutive approach toward computational modeling. Characterizing the properties of the native insertion tissue would provide the microstructural basis for developing biomimetic scaffolds to recreate the graded morphology of a fibrocartilaginous insertion. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3050–3058, 2017.
Some metals inhibit the glutathione S‐transferase from Van Lake fish gills
Authors: Özaslan M. Serhat , Demir Yeliz , Küfrevioğlu O. Irfan , Çiftci Mehmet
Published: July 2017

Glutathione S‐transferases (GSTs) are the superfamily of multifunctional detoxification isoenzymes and play important role cellular signaling. The present article focuses on the role of Cd2+, Cu2+, Zn2+, and Ag+ in vitro inhibition of GST. For this purpose, GST was purified from Van Lake fish (Chalcalburnus tarichii Pallas) gills with 110.664 EU mg−1 specific activity and 79.6% yield using GSH‐agarose affinity chromatographic method. The metal ions were tested at various concentrations on in vitro GST activity. IC50 values were found for Cd+2, Cu+2, Zn+2, Ag+ as 450.32, 320.25, 1510.13, and 16.43 μM, respectively. Ki constants were calculated as 197.05 ± 105.23, 333.10 ± 152.76, 1670.21 ± 665.43, and 0.433 ± 0.251 μM, respectively. Ag+ showed better inhibitory effect compared with the other metal ions. The inhibition mechanisms of Cd2+ and Cu2+ were non‐competitive, whereas Zn2+ and Ag+ were competitive. Co2+, Cr2+, Pb2+, and Fe3+ had no inhibitory activity on GST.
Effects of early combinatorial treatment of autologous split‐thickness skin grafts in red duroc pig model using pulsed dye laser and fractional CO2 laser
Authors: Bailey J. Kevin , Blackstone Britani N. , DeBruler Danielle M. , Kim Jayne Y. , Baumann Molly E. , McFarland Kevin L. , Imeokparia Folasade O. , Supp Dorothy M. , Powell Heather M.
Published: July 2017

Background and Objective

The use of pulsed dye laser (PDL) and fractional CO2 (FX CO2) laser therapy to treat and/or prevent scarring following burn injury is becoming more widespread with a number of studies reporting reduction in scar erythema and pruritus following treatment with lasers. While the majority of studies report positive outcomes following PDL or FX CO2 therapy, a number of studies have reported no benefit or worsening of the scar following treatment. The objective of this study was to directly compare the efficacy of PDL, FX CO2, and PDL + FX CO2 laser therapy in reducing scarring post burn injury and autografting in a standardized animal model.

Materials and Methods

Eight female red Duroc pigs (FRDP) received 4 standardized, 1 in. x 1 in. third degree burns that were excised and autografted. Wound sites were treated with PDL, FX CO2, or both at 4, 8, and 12 weeks post grafting. Grafts receiving no laser therapy served as controls. Scar appearance, morphology, size, and erythema were assessed and punch biopsies collected at weeks 4, 8, 12, and 16. At week 16, additional tissue was collected for biomechanical analyses and markers for inflammatory cytokines, extracellular matrix (ECM) proteins, re‐epithelialization, pigmentation, and angiogenesis were quantified at all time points using qRT‐PCR.

Results

Treatment with PDL, FX CO2, or PDL + FX CO2 resulted in significantly less contraction versus skin graft only controls with no statistically significant difference among laser therapy groups. Scars treated with both PDL and FX CO2 were visually more erythematous than other groups with a significant increase in redness between two and three standard deviations above normal skin redness. Scars treated with FX CO2 were visually smoother and contained significantly fewer wrinkles. In addition, hyperpigmentation was significantly reduced in scars treated with FX CO2.

Conclusions

The use of fractional carbon dioxide or pulsed dye laser therapy within 1 month of autografting significantly reduced scar contraction versus control, though no statistically significant difference was detected between laser modalities or use of both modalities. Overall, FX CO2 therapy appears to be modestly more effective at reducing erythema, and improving scar texture and biomechanics. The current data adds to prior studies supporting the role of laser therapy in the treatment of burn scars and indicates more study is needed to optimize delivery protocols for maximum efficacy. Lasers Surg. Med. 50:78–87, 2018. © 2017 Wiley Periodicals, Inc.
Intersection Poincaré Polynomial for Nagaraj–Seshadri moduli space
Authors: Barik Pabitra , Dey Arijit , Suhas B. N.
Published: July 2017

We compute Betti numbers of both the components of the moduli space of rank 2 semi‐stable torsion‐free sheaves with fixed determinant over a reducible nodal curve with two smooth components intersecting at a node. We also compute the intersection Betti numbers of the moduli space.
Serine alleviates oxidative stress via supporting glutathione synthesis and methionine cycle in mice
Authors: Zhou Xihong , He Liuqin , Wu Canrong , Zhang Yumei , Wu Xin , Yin Yulong
Published: July 2017

Scope

Serine lies at the central node linking biosynthetic flux from glycolysis to glutathione synthesis and one‐carbon metabolic cycle which are closely related to antioxidant capacity. The present study was conducted to determine the effects of serine supplementation on oxidative stress and its relative mechanisms.

Methods and results

Diquat treatment was performed to induce oxidative stress in mice and primary hepatocytes. The results showed that hepatic glutathione anti‐oxidant systems were impaired and reactive oxygen species and homocysteine were increased in diquat‐induced mice and hepatocytes, while such disadvantageous changes were diminished by serine supplementation both in vivo and in vitro. However, when cystathionine β‐synthase expression was inhibited by interference RNA in hepatocytes, the effects of serine supplementation on the improvement of glutathione synthesis and the alleviation of oxidative stress were diminished. Moreover, when hepatocytes were treated with cycloleucine, an inhibitor of methionine adenosyltransferase, the effects of serine supplementation on the improvement of methionine cycle and the alleviation of DNA hypomethylation and oxidative stress were also diminished.

Conclusion

Our results indicated that serine supplementation alleviated oxidative stress via supporting glutathione synthesis and methionine cycle, mostly by condensing with homocysteine to synthesize cysteine and providing one‐carbon units for homocysteine remethylation.
Fabrication of poly(vinyl alcohol) nanocomposites having different contents of modified SiO2 by vitamin B1 as biosafe and novel coupling agent to improve mechanical and thermal properties
Authors: Mallakpour Shadpour , Khani Zahra
Published: July 2017

In this study, at first, owing to the excessive surface energy and inclination for aggregation, surface treatment of silica (SiO2) nanoparticles (NP)s was performed by vitamin B1 (VB1) as a biodegradable and biocompatible coupling agent. The divergent extent of modified SiO2 (SiO2‐VB1) was incorporated into poly(vinyl alcohol) (PVA) matrix and PVA/SiO2‐VB1 nanocomposites (NC)s were prepared. TGA analysis showed that the insertion of SiO2‐VB1 into the PVA improved its thermal resistance. Microscopic observations showed that SiO2‐VB1 was in average size about 24 nm and was homogeneously dispersed in the PVA matrix. As reported by UV‐Vis spectra, the absorption was raised by increasing the percentage of SiO2 NPs. Water contact angle analysis indicated that the obtained NCs showed more hydrophilicity property than the neat PVA. Also, a mechanical tensile test of the NCs showed more flexibility than that of the pure PVA. POLYM. COMPOS., 39:E1589–E1597, 2018. © 2017 Society of Plastics Engineers
One patient at a time, please!
Authors: Delvin David
Published: July 2017

‘Two for the price of one’ is not a tempting offer when it comes to patient appointments, as Dr David Delvin explains.
A wavelet threshold denoising procedure for multimodel predictions: An application to economic time series
Authors: Fenga Livio
Published: July 2017

Noise‐affected economic time series, realizations of stochastic processes exhibiting complex and possibly nonlinear dynamics, are dealt with. This is often the case of time series found in economics, which notoriously suffer from problems such as low signal‐to‐noise ratios, asymmetric cycles and multiregimes patterns. In such a framework, even sophisticated statistical models might generate suboptimal predictions, whose quality can further deteriorate unless time consuming updating or deeper model revision procedures are carried out on a regular basis. However, when the models' outcomes are expected to be disseminated in timeliness manner (as in the case of Central Banks or national statistical offices), their modification might not be a viable solution, due to time constraints. On the other hand, if the application of simpler linear models usually entails relatively easier tuning‐up procedures, this would come at the expenses of the quality of the predictions yielded. A mixed, self‐tuning forecasting method is therefore proposed. This is an automatic, 2‐stage procedure, able to generate predictions by exploiting the denoising capabilities provided by the wavelet theory in conjunction with a compounded forecasting generator. Its out‐of‐sample performances are evaluated through an empirical study carried out on macroeconomic time series.
25 years post‐Calman: the state of men's health in the UK
Authors: Baker Peter
Published: July 2017

25 years have passed since the then Chief Medical Officer, Sir Kenneth Calman, included men's health as a ‘special topic’ in his annual public health report.1 Peter Baker reflects on what has been achieved in the men's health field during this time and what issues remain in need of attention.