bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plant nurse effects rely on combined hydrological and ecological components in a semiarid ecosystem
Authors: Pueyo Yolanda , Moret‐Fernández David , Arroyo Antonio I. , de Frutos Angel , Kéfi Sonia , Saiz Hugo , Charte Raquel , Giner María de la Luz , Alados Concepción L. 
Published: October 2016

AbstractPlant establishment in semiarid ecosystems is affected by the limited spatial and temporal availability of resources and adequate microsites provided by nurse plants. There has been little research on plant establishment in these ecosystems that consider both the ecological roles of different plant types and the abiotic properties of their microsites. Such studies could provide important insights about the functioning of semiarid ecosystems. Here, we investigated the links between the patterns of plant establishment and the hydrological and microsite properties of shrubs and grasses in a semiarid ecosystem northeastern Spain. For ecological experiments, we measured the spatial patterns of the establishment of shrubs and grasses in eight 6 × 6 m2 quadrats over 2 years; we also sowed seeds of Salsola vermiculata (a dominant shrub) and Lygeum spartum (the dominant perennial grass) under adult shrubs (S. vermiculata) and grasses (L. spartum) and in bare soil and then examined seedling germination, survival, and growth over 4 years. For hydrological experiments, we analyzed soil water content under the two codominant shrubs (S. vermiculata and Artemisia herba‐alba), the dominant perennial grass (L. spartum), and in bare soil over 18 months; we also measured water infiltration and solar radiation at the same four microsites to identify the hydrological processes responsible for the observed ecohydrological patterns. The three potential nurse plants greatly improved the hydrological and microsite conditions. They increased soil water content after rainfall relative to bare soil. Moreover, S. vermiculata and L. spartum slowed the drying process. However, only S. vermiculata acted as a nurse plant. It improved plant density, diversity, performance, and survival during the whole study period. L. spartum facilitated plant establishment during early stages, but interfered with seedling performance and survival during later stages, probably because of the increasing competition for water with seedlings. A. herba‐alba did not facilitate plant establishment at any stage, most likely because of water scarcity during prolonged dry periods and its allelopathic effects. We conclude that the ecological role of a plant cannot be directly inferred from its hydrological or microsite properties. Long‐term ecohydrological studies are required to understand the role of nurse plants on seedling establishment.
Forecasting climate change impacts on plant populations over large spatial extents
Authors: Tredennick Andrew T. , Hooten Mevin B. , Aldridge Cameron L. , Homer Collin G. , Kleinhesselink Andrew R. , Adler Peter B. 
Published: October 2016

AbstractPlant population models are powerful tools for predicting climate change impacts in one location, but are difficult to apply at landscape scales. We overcome this limitation by taking advantage of two recent advances: remotely sensed, species‐specific estimates of plant cover and statistical models developed for spatiotemporal dynamics of animal populations. Using computationally efficient model reparameterizations, we fit a spatiotemporal population model to a 28‐year time series of sagebrush (Artemisia spp.) percent cover over a 2.5 × 5 km landscape in southwestern Wyoming while formally accounting for spatial autocorrelation. We include interannual variation in precipitation and temperature as covariates in the model to investigate how climate affects the cover of sagebrush. We then use the model to forecast the future abundance of sagebrush at the landscape scale under projected climate change, generating spatially explicit estimates of sagebrush population trajectories that have, until now, been impossible to produce at this scale. Our broadscale and long‐term predictions are rooted in small‐scale and short‐term population dynamics and provide an alternative to predictions offered by species distribution models that do not include population dynamics. Our approach, which combines several existing techniques in a novel way, demonstrates the use of remote sensing data to model population responses to environmental change that play out at spatial scales far greater than the traditional field study plot.
Association of beta‐blocker treatment with mortality following myocardial infarction in patients with chronic obstructive pulmonary disease and heart failure or left ventricular dysfunction: a propensity matched‐cohort analysis from the High‐Risk Myocardial Infarction Database Initiative
Authors: Coiro Stefano , Girerd Nicolas , Rossignol Patrick , Ferreira João Pedro , Maggioni Aldo , Pitt Bertram , Tritto Isabella , Ambrosio Giuseppe , Dickstein Kenneth , Zannad Faiez 
Published: October 2016

AimsTo determine the influence of baseline beta‐blocker use on long‐term prognosis of myocardial infarction (MI) survivors complicated with heart failure (HF) or with left ventricular dysfunction and with history of chronic obstructive pulmonary disease (COPD).Methods and resultsAmong the 28 771 patients from the High‐Risk MI Database Initiative we identified 1573 patients with a baseline history of COPD. We evaluated the association between beta‐blocker use at baseline (822 with beta‐blocker and 751 without) on the rates of all‐cause and cardiovascular mortality. On univariable Cox analysis, beta‐blocker use was found to be associated with lower rates of both all‐cause [hazard ratio (HR) = 0.61, 95% confidence interval (CI) 0.51–0.75, P < 0.0001] and cardiovascular mortality (HR = 0.63, 95% CI 0.51–0.78, P < 0.0001). After extensive adjustment for confounding, including 24 baseline covariates, COPD patients still benefited from beta‐blocker usage (HR = 0.73, 95% CI 0.60–0.90, P = 0.002 for all‐cause mortality; HR = 0.77, 95% CI 0.61–0.97, P = 0.025 for cardiovascular mortality). Adjusting for propensity scores (PS) constructed from the 24 aforementioned baseline characteristics provided similar results. In a cohort of 561 pairs of patients taking or not taking beta‐blocker matched on PS using a 1:1 nearest‐neighbour matching method, patients treated with beta‐blocker experienced fewer all‐cause deaths (HR = 0.71, 95% CI 0.56–0.89, P = 0.003) and cardiovascular deaths (HR = 0.76, 95% CI 0.59–0.97, P = 0.032).ConclusionsIn the specific setting of a well‐treated cohort of high‐risk MI survivors, beta‐blockers were associated with better outcomes in patients with COPD.
Studying the effect of microwave heating on the digestion process and identification of proteins
Authors: Devi Shobha , Wu Bo‐Hung , Chu Pei‐Yu , Liu Yue‐Pei , Wu Hsin‐Lin , Ho Yen‐Peng 
Published: October 2016

The impact of microwave irradiation on the in‐solution digestion processes and the detection limit of proteins are systematically studied. Kinetic processes of many peptides produced through the trypsin digestion of various proteins under microwave heating at 50°C were investigated with MALDI‐MS. This study also examines the detection limits and digestion completeness of individual proteins under microwave heating at 50°C and at different time intervals (1, 5 and 30 min) using LC‐MS. We conclude that if the peptides without missed cleavage dictate the detection limit, conventional digestion will lead to a better detection limit. The detection limit may not differ between the microwave and conventional heating if the peptides with missed cleavage sites and strong intensity are formed at the very early stage (i.e., less than 1 min) and are not further digested throughout the entire digestion process. The digestion of Escherichia coli lysate was compared under conventional and short time (microwave) conditions. The number of proteins identified under conventional heating exceeded that obtained from microwave heating over heating periods less than 5 min. The overall results show that the microwave‐assisted digestion is not complete. Although the sequence coverage might be better, the detection limit might be worse than that under conventional heating.
Constant denudation rates in a high alpine catchment for the last 6 kyrs
Authors: Grischott R. , Kober F. , Lupker M. , Hippe K. , Ivy‐Ochs S. , Hajdas I. , Salcher B. , Christl M. 
Published: October 2016

AbstractTerrestrial cosmogenic nuclides (TCN) have widely been used as proxies in determining denudation rates in catchments. Most studies were limited to samples from modern active streams, thus little is known about the magnitude and causes of TCN variability on millennial time scales. In this work we present a 6 kyrs long, high resolution record of 10Be concentrations (n = 18), which were measured in sediment cores from an alluvial fan delta at the outlet of the Fedoz Valley in the Swiss Alps. This record is paired with a 3‐year time series (n = 4) of 10Be measured in sediment from the active stream currently feeding this fan delta. The temporal trend in the 10Be concentrations after correction for postdepositional production of 10Be was found to be overall constant and in good agreement with the modern river 10Be concentration. The calculated mean catchment‐wide denudation rate amounts to 0.73 ± 0.18 mm yr−1. This fairly constant level of 10Be concentrations can be caused by a constant denudation rate over time within the catchment or alternatively by a buffered signal. In this contribution we suggest that the large alluvial floodplain in the Fedoz Valley may act as an efficient buffer on Holocene time scales in which sediments with different 10Be signatures are mixed. Therefore, presumable variations in the 10Be signals derived from changes in denudation under a fluctuating Holocene climate are only poorly transferred to the catchment outlet and not recorded in the 10Be record. However, despite the absence of high frequency signals, we propose that the buffered and averaged 10Be signal could be meaningfully and faithfully interpreted in terms of long‐term catchment‐averaged denudation rate. Our study suggests that alluvial buffers play an important role in regulating the 10Be signal exported by some alpine settings that needs to be taken into account and further investigated. Copyright © 2016 John Wiley & Sons, Ltd.
Climate change and soil erosion in a small alpine lake basin on the Loess Plateau, China
Authors: Yu Keke , Xu Hai , Lan Jianghu , Sheng Enguo , Liu Bin , Wu Huixian , Tan Liangcheng , Yeager Kevin M. 
Published: October 2016

AbstractMulti‐proxy indices retrieved from sediments in Lake Chaonaqiu, an alpine lake on the western Loess Plateau (LP) of China, were used to reconstruct a precipitation history over the last ~300 years. The results correlate well with records from tree rings and historical documents in neighboring regions. We show that the lake oscillated between two states, i.e. wetter climatic conditions, which favored denser vegetation cover, and promoted weaker catchment soil erosion; and drier climatic conditions, which lead to less vegetation coverage, correlate with stronger surface soil erosion. Several intensive soil erosion events were identified in the sediment cores, and most of these occurred during decadal/multi‐decadal dry periods, and correlate well with flood events documented in historical literature. The results of this study show that soil erosion by flood events is particularly intense during dry periods, and further highlights the role of vegetation cover in the conservation of water and soil in small lake basins on the Chinese LP. Copyright © 2016 John Wiley & Sons, Ltd.
Combined effects of road salt and an insecticide on wetland communities
Authors: Stoler Aaron B. , Walker Brent M. , Hintz William D. , Jones Devin K. , Lind Lovisa , Mattes Brian M. , Schuler Matthew S. , Relyea Rick A. 
Published: October 2016

Abstract

As the numbers of chemical contaminants in freshwater ecosystems increase, it is important to understand whether contaminants interact in ecologically important ways. The present study investigated the independent and interactive effects of 2 contaminants that frequently co-occur in freshwater environments among higher latitudes, including a commonly applied insecticide (carbaryl) and road salt (NaCl). The hypothesis was that the addition of either contaminant would result in a decline in zooplankton, an algal bloom, and the subsequent decline of both periphyton and periphyton consumers. Another hypothesis was that combining the contaminants would result in synergistic effects on community responses. Outdoor mesocosms were used with communities that included phytoplankton, periphyton, zooplankton, amphipods, clams, snails, and tadpoles. Communities were exposed to 4 environmentally relevant concentrations of salt (27 mg Cl– L−1, 77 mg Cl– L−1, 277 mg Cl– L−1, and 727 mg Cl– L−1) fully crossed with 4 carbaryl treatments (ethanol, 0 µg L−1, 5 µg L−1, and 50 µg L−1) over 57 d. Contaminants induced declines in rotifer and cladoceran zooplankton, but only carbaryl induced an algal bloom. Consumers exhibited both positive and negative responses to contaminants, which were likely the result of both indirect community interactions and direct toxicity. In contrast to the hypothesis, no synergistic effects were found, although copepod densities declined when high concentrations of both chemicals were combined. The results suggest that low concentrations of salt and carbaryl are likely to have mostly independent effects on aquatic communities. Environ Toxicol Chem 2017;36:771–779. © 2016 SETAC
Improved quantification of collagen anisotropy with polarization‐resolved second harmonic generation microscopy
Authors: Hristu Radu , Stanciu Stefan G. , Tranca Denis E. , Stanciu George A. 
Published: October 2016

Imaging tissue samples by polarization‐resolved second harmonic generation microscopy provides both qualitative and quantitative insights into collagen organization in a label‐free manner. Polarization‐resolved second harmonic generation microscopy goes beyond simple intensity‐based imaging by adding the laser beam polarization component and applying different quantitative metrics such as the anisotropy factor. It thus provides valuable information on collagen arrangement not available with intensity measurements alone. Current established approaches are limited to calculating the anisotropy factor for only a particular laser beam polarization and no general guidelines on how to select the best laser beam polarization have yet been defined. Here, we introduce a novel methodology for selecting the optimal laser beam polarization for characterizing tissues using the anisotropy in the purpose of identifying cancer signatures. We show that the anisotropy factor exhibits a similar laser beam polarization dependence to the second harmonic intensity and we combine it with the collagen orientation index computed by Fast Fourier Transform analysis of the recorded images to establish a framework for choosing the laser beam polarization that is optimal for an accurate interpretation of polarization‐resolved second harmonic generation microscopy images and anisotropy maps, and hence a better differentiation between healthy and dysplastic areas.
SHG image of skin tissue (a) and a selected area of interest for which we compute the SHG intensity (b) and anisotropy factor (c) dependence on the laser beam polarization and also the FFT spectrum (d) to evaluate the collagen orientation index.magnified imageSHG image of skin tissue (a) and a selected area of interest for which we compute the SHG intensity (b) and anisotropy factor (c) dependence on the laser beam polarization and also the FFT spectrum (d) to evaluate the collagen orientation index.
Reference‐independent wide field fluorescence lifetime measurements using Frequency‐Domain (FD) technique based on phase and amplitude crossing point
Authors: Yahav Gilad , Barnoy Eran , Roth Nir , Turgeman Lior , Fixler Dror 
Published: October 2016

Fluorescence lifetime imaging microscopy (FLIM) is an essential tool in many scientific fields such as biology and medicine thanks to the known advantages of the fluorescence lifetime (FLT) over the classical fluorescence intensity (FI). However, the frequency domain (FD) FLIM technique suffers from its strong dependence on the reference and its compliance to the sample. In this paper, we suggest a new way to calculate the FLT by using the crossing point (CRPO) between the modulation and phase FLTs measured over several light emitting diode (LED) DC currents values instead of either method alone.This new technique was validated by measuring homogeneous substances with known FLT, where the CRPO appears to be the optimal measuring point. Furthermore, the CRPO method was applied in heterogeneous samples. It was found that the CRPO in known mixed solutions is the weighted average of the used solutions. While measuring B16 and lymphocyte cells, the CRPO of the DAPI compound in single FLT regions was measured at 3.5 ± 0.06 ns and at 2.83 ± 0.07 ns, respectively, both of which match previous reports and multi‐frequency analyses. This paper suggests the CRPO as a new method to extract the FLT in problematic cases such as high MCP gains and heterogeneous environments.
In traditional FD FLIM measurements, the variation in phase angle and modulation are measured. By measuring over varying DC currents, another variation is detected in the FLT determined through the phase and modulation methods, with the CRPO indicating the true FLT.magnified imageIn traditional FD FLIM measurements, the variation in phase angle and modulation are measured. By measuring over varying DC currents, another variation is detected in the FLT determined through the phase and modulation methods, with the CRPO indicating the true FLT.
Differential magnesium implant corrosion coat formation and contribution to bone bonding
Authors: Rahim Muhammad Imran , Weizbauer Andreas , Evertz Florian , Hoffmann Andrea , Rohde Manfred , Glasmacher Birgit , Windhagen Henning , Gross Gerhard , Seitz Jan‐Marten , Mueller Peter P. 
Published: October 2016

AbstractMagnesium alloys are presently under investigation as promising biodegradable implant materials with osteoconductive properties. To study the molecular mechanisms involved, the potential contribution of soluble magnesium corrosion products to the stimulation of osteoblastic cell differentiation was examined. However, no evidence for the stimulation of osteoblast differentiation could be obtained when cultured mesenchymal precursor cells were differentiated in the presence of metallic magnesium or in cell culture medium containing elevated magnesium ion levels. Similarly, in soft tissue no bone induction by metallic magnesium or by the corrosion product magnesium hydroxide could be observed in a mouse model. Motivated by the comparatively rapid accumulation solid corrosion products physicochemical processes were examined as an alternative mechanism to explain the stimulation of bone growth by magnesium‐based implants. During exposure to physiological solutions a structured corrosion coat formed on magnesium whereby the elements calcium and phosphate were enriched in the outermost layer which could play a role in the established biocompatible behavior of magnesium implants. When magnesium pins were inserted into avital bones, corrosion lead to increases in the pull out force, suggesting that the expanding corrosion layer was interlocking with the surrounding bone. Since mechanical stress is a well‐established inducer of bone growth, volume increases caused by the rapid accumulation of corrosion products and the resulting force development could be a key mechanism and provide an explanation for the observed stimulatory effects of magnesium‐based implants in hard tissue. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 697–709, 2017.
Biocompatibility and toxicology effects of graphene oxide in cancer, normal, and primary immune cells
Authors: Martinez Paino Iêda Maria , Santos Fabrício , Zucolotto Valtencir 
Published: October 2016

AbstractGraphene oxide (GO) has received enormous attention regarding its possible applications in medical areas including cancer treatment. Nevertheless, graphene biocompatibility and its interactions with cancer, normal and immune system cells still remain a major issue. In the current study, we focused on the immunological impact of GO in the oxidative burst by GO produced in fresh isolated primary human neutrophils, the most abundant leukocyte of immune system. We also studied the GO cytotoxicity, cell uptake, and genotoxicity in fresh isolated primary human monocyte, neutrophil, human carcinoma cervical (HeLa) and L929 cells. GO biocompatibility was also analyzed in human red blood cell (hemocompatibility) and in primary human T lymphocytes (T cell). We observed that GO can interact with HeLa in vitro and immune system cells, but in major extension with cancer cells. The latter opened the way for further studies on the effects of GO on immune system pathways and treatments for human cancer at lower concentrations. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 728–736, 2017.
Clinically Relevant Concentrations of Ketamine Inhibit Osteoclast Formation In Vitro in Mouse Bone Marrow Cultures
Authors: Du Erxia , McAllister Patrick , Venna Venugopal Reddy , Xiao Liping 
Published: October 2016

ABSTRACTKetamine has been used safely in clinics for decades for analgesia and anesthesia. It is increasingly popular in clinical practice due to its new uses and importance for emergency procedures. It is known that ketamine is sequestered in the bone marrow and the major receptors for ketamine, noncompetitive N‐methyl‐d‐aspartate receptors (NMDARs), are expressed in osteoclasts (OCs) and osteoblasts. However, the impact of ketamine on OCs or osteoblasts is unknown. In this study, we investigated the effects of ketamine on osteoclastogenesis and regulation of NMDARs expression in vitro. Bone marrows (BMs) or bone marrow macrophages (BMMs) were cultured in the presence of macrophage colony‐stimulating factor (M‐CSF) and receptor activator of nuclear factor kappa‐B ligand (RANKL) with or without ketamine for up to 6 days. OC formation peaked at day 5. On day 5 of culture, ketamine inhibited OC formation from both BM and BMM cultures at clinically relevant concentrations (3–200 µM). Ketamine inhibited RANKL‐induced expression of nuclear factor of activated T‐cells, cytoplasmic, calcineurin‐dependent 1 (NFATc1) in BMM cultures. Inhibition of ketamine on RANKL‐induced osteoclastogenesis is associated with down‐regulation of NMDARs. In addition, ketamine significantly inhibited the M‐CSF induced migration of BMMs, inhibited cell fusion and significantly increased mature OC apoptosis. We conclude that clinically relevant concentrations of ketamine inhibit OC formation in both BM and BMM cultures in vitro through inhibiting migration and fusion process and enhancing mature OC apoptosis. It is likely that ketamine regulates osteoclastogenesis, at least in part, via its effects on NMDAR expression. J. Cell. Biochem. 118: 914–923, 2017. © 2016 Wiley Periodicals, Inc.