bluuebunny/crossref_metadata_2025_split huggingface dataset:
Habitat fragmentation reduces plant progeny quality: a global synthesis
Authors: Aguilar Ramiro , Cristóbal‐Pérez Edson Jacob , Balvino‐Olvera Francisco Javier , de Jesús Aguilar‐Aguilar María , Aguirre‐Acosta Natalia , Ashworth Lorena , Lobo Jorge A. , Martén‐Rodríguez Silvana , Fuchs Eric J. , Sanchez‐Montoya Gumersindo , Bernardello Gabriel , Quesada Mauricio 
Published: May 2019

AbstractMost of the world's land surface is currently under human use and natural habitats remain as fragmented samples of the original landscapes. Measuring the quality of plant progeny sired in these pervasive environments represents a fundamental endeavour for predicting the evolutionary potential of plant populations remaining in fragmented habitats and thus their ability to adapt to changing environments. By means of hierarchical and phylogenetically independent meta‐analyses we reviewed habitat fragmentation effects on the genetic and biological characteristics of progenies across 179 plant species. Progeny sired in fragmented habitats showed overall genetic erosion in contrast with progeny sired in continuous habitats, with the exception of plants pollinated by vertebrates. Similarly, plant progeny in fragmented habitats showed reduced germination, survival and growth. Habitat fragmentation had stronger negative effects on the progeny vigour of outcrossing‐ than mixed‐mating plant species, except for vertebrate‐pollinated species. Finally, we observed that increased inbreeding coefficients due to fragmentation correlated negatively with progeny vigour. Our findings reveal a gloomy future for angiosperms remaining in fragmented habitats as fewer sired progeny of lower quality may decrease recruitment of plant populations, thereby increasing their probability of extinction.
Antibiotics use and risk of amyotrophic lateral sclerosis in Sweden
Authors: Sun J. , Zhan Y. , Mariosa D. , Larsson H. , Almqvist C. , Ingre C. , Zagai U. , Pawitan Y. , Fang F. 
Published: May 2019

Background and purposePrevious animal studies have suggested a disrupted intestinal microbiome in amyotrophic lateral sclerosis (ALS). Due to the known effect of antibiotics on gut microflora, the potential role of antibiotics use on the risk of ALS deserves an investigation.MethodsA nested case–control study was conducted using several Swedish national registers. In all, 2484 ALS patients diagnosed between 1 July 2006 and 31 December 2013 were included as cases, and five controls per case individually matched to the case by sex, birth year and area of residence were randomly selected from the general Swedish population. Information on antibiotics prescriptions before ALS diagnosis was extracted from the Prescribed Drug Register for both cases and controls. A conditional logistic regression model was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs).ResultsAfter accounting for potential diagnostic delay in ALS by excluding all prescriptions within 1 year before diagnosis, any antibiotics use was associated with a higher risk of ALS. The ORs (95% CIs) were 1.06 (0.94–1.19), 1.13 (1.00–1.28) and 1.18 (1.03–1.35) when comparing 1, 2–3 and ≥4 prescriptions to no prescription (P for trend = 0.0069). Similar results were noted for antibiotics used for respiratory infections and urinary tract as well as skin and soft tissue infections. Amongst different individual antibiotics, the risk of ALS was especially increased in relation to more than two prescriptions of beta‐lactamase sensitive penicillin (OR 1.28; 95% CI 1.10–1.50).ConclusionsUse of antibiotics, especially repeated, might be associated with a higher subsequent risk of ALS.
Intra‐articular anaesthesia of the equine stifle improves foot lameness
Authors: Radtke A. , Fortier L. A. , Regan S. , Kraus S. , Delco M. L. 
Published: May 2019

SummaryBackgroundEquine diagnostic anaesthesia can be a useful tool in challenging lameness examinations. However, anaesthetics diffuse over time leading to nonspecific desensitisation of periarticular structures. Nerves that convey sensation from the distal limb to the central nervous system pass in close proximity to the caudal stifle joint capsule. Therefore, diffusion of intra‐articular (IA) anaesthetics could cause inadvertent desensitisation of the distal limb resulting in a false diagnosis of stifle lameness.ObjectivesTo determine if IA stifle anaesthesia can alleviate lameness originating in the distal limb.Study designCrossover experiment.MethodsNine horses were fitted with a circumferential hoof clamp to induce a moderate unilateral hindlimb lameness. Intra‐articular stifle anaesthesia was performed and gait was evaluated every 10 min during the 90‐min trial using an inertial sensor system. Push‐off and landing components of the lameness were assessed by measuring the mean inter‐stride difference between the maximum and minimum heights of the pelvis respectively. Differences were compared using a Wilcoxon signed‐rank test.ResultsOverall, horses with hoof clamp‐induced foot pain had a reduction in push‐off lameness after IA stifle anaesthesia. The mean change in diffmax at 90 min was −4.3 mm (P = 0.005) for the experimental group vs. −2.3 mm (P = 0.2) for the control group. Lameness decreased over time, with an average improvement of 23% at 30 min, 33% at 60 min and 38% at 90 min. There was high inter‐horse variability; 3/9 horses improved by ~50% within 30 min, while 2/9 improved by ~30% and 4/9 had minimal (<10%) or no improvement in lameness. Improvement after IA stifle anaesthesia was not related to the severity of baseline lameness (P = 0.3–0.7).Main limitationsLimited clinical applicability of our lameness induction model.ConclusionsIntra‐articular stifle anaesthesia reduces foot lameness in a third of horses by up to 50% within 30 min. Clinically, the results of IA stifle anaesthesia should be considered in the light of these findings before treatment recommendations are made, as additional diagnostics may be required to rule out pain originating in the distal limb.
Streamlined eco‐engineering approach helps define environmental flows for tropical Andean headwaters
Authors: Rosero‐López Daniela , Walter M. Todd , Flecker Alexander S. , Lloret Pablo , De Bièvre Bert , González‐Zeas Dunia , Calvez Roger , Dangles Olivier 
Published: May 2019

Abstract

Applying the environmental flows concept to human‐altered lotic ecosystems continues to face many practical challenges and barriers. Here, we modify a previously proposed framework, the Eco‐Engineering Decision Scaling, for application to part of the water supply system of Quito, Ecuador.

Specifically, we used feedback from engineers and water managers to develop a common set of metrics for defining flow‐ecology relationships and assess managed‐flow impacts on stream ecology. At 12 sites over 3 years, we collected flow and benthic invertebrate data (taxonomic richness, taxa important for fish, functional feeding groups, and water quality‐sensitive taxa) during wet and dry seasons. We then used these data to identify flow thresholds (relative to unmanaged flows) where flow withdrawal caused visible ecological impacts.

For this system, reduction of flow to 20% of the annual median was detrimental to benthic communities, while reductions to 40% of the annual median flow caused a variety of responses in the system. A trade‐off analysis of weighted metrics showed that a 50% benthic fauna richness could be sustained if dry season flows were maintained between 28% and 40% of the unmanaged median annual flow. This study provides a roadmap for bridging between eco‐engineering theoretical frameworks and the adoption of the environmental flows concept as actionable management thresholds.
The spatial scale dependence of diazotrophic and bacterial community assembly in paddy soil
Authors: Gao Qun , Yang Yunfeng , Feng Jiajie , Tian Renmao , Guo Xue , Ning Daliang , Hale Lauren , Wang Mengmeng , Cheng Jingmin , Wu Linwei , Zhao Mengxin , Zhao Jianshu , Wu Liyou , Qin Yujia , Qi Qi , Liang Yuting , Sun Bo , Chu Haiyan , Zhou Jizhong 
Published: May 2019

AbstractAimThe factors driving microbial community β‐diversity (variation in composition) at different spatial scales yield fundamental insights into the mechanisms that maintain ecosystem biodiversity, which as yet are uncertain. Here, we explore whether spatial scale‐dependent patterns of β‐diversity vary between microbial functional groups and bacterial taxa (i.e., diazotrophic and bacterial communities) across local to regional scales (from metres to hundreds of kilometres).LocationEastern China.Time periodOctober and November 2015.Major taxa studiedDiazotrophic and bacterial communities.MethodsWe use two complementary statistical tools to unveil biotic mechanisms (i.e., species association) underlying variation in β‐diversity of diazotrophic and bacterial communities. We examined distance–decay slopes of both communities at the local (1–113 m), meso‐ (3.4–39 km) and regional (103–668 km) scales. We used an environmentally constrained checkerboard score and topological features of association networks as indices of species association. We then calculated contributions of species association, abiotic factors and geographical distance to explain community β‐diversity. The scale‐dependent distance–decay relationships were also examined in ubiquitous (high occupancy across samples) and endemic communities of diazotrophs and bacteria.ResultsDiazotrophs displayed steeper distance–decay slopes than bacteria, suggesting that the β‐diversity of diazotrophic communities was more variable. The distance–decay slopes were dependent on spatial scales in both communities, owing to different contributions of geographical distance, abiotic factors and species association at three spatial scales. Intriguingly, species association was greater and contributed more to community β‐diversity than other forces at the local scale, implying that species association could greatly alter community structures.Main conclusionsDrivers of diazotrophic and bacterial community β‐diversity depended on spatial scales, resulting in different distance–decay patterns. Moreover, this was the first study to use two methods to demonstrate that species association played important, but as yet unrecognized, roles in driving spatial scale‐dependent β‐diversity.
Seasonal and diurnal relationship of forage nutritive value and mass in a tall fescue pasture under continuous stocking
Authors: La Guardia Nave Renata , Corbin Michael Dereck 
Published: May 2019

AbstractMonitoring forage mass and nutritive value of pastures are encouraged to ensure adequate and efficient grazing management. For on‐farm monitoring, reliable instruments such as the rising plate meter (RPM) are useful and easy to achieve. The objective of this research was to verify the relationship between measurements of RPM (MRPM) to forage nutritive value based on seasonal and diurnal changes within a tall fescue sward under continuous stocking management. The study was conducted at the Plateau AgResearch and Education Center in Crossville, TN, from January 2015 to December 2016. The experiment was conducted in two 9‐hectare pastures consisting of a tall fescue [Schedonorus arundinaceus (Schreb.) Dumort., nom. cons., formerly Festuca arundinacea Schreb.] sward. During the 12‐month grazing period each year, total aboveground available forage was measured monthly in each pasture with a calibrated RPM. In addition, each month, several randomly placed 1‐m2 sample areas were collected at 7 a.m., 9 a.m., 12 p.m. and 4 p.m. to characterize forage nutritive value. Neutral detergent fiber, crude protein and in vitro total dry matter digestibility (IVTDMD) were predicted by means of near‐infrared spectroscopy. During the entire year of 2015, all correlation coefficients of forage nutritive value variables with MRPM were significant. However, in 2016, only IVTDMD showed a significant correlation with MRPM. Of the nutritive value variables, we chose to focus on the IVTDMD and MRPM relationship because it had one of the highest correlations for most seasons and different times of day, especially in 2015. There was a strong relationship between RPM measurements of herbage mass with IVTDMD, and this relationship is especially useful during the spring, where rapid growth is occurring. The same relationship was not found to be consistent during periods of slow forage growth, especially if recovering from a drought event.
Yellow fever and orthotopic liver transplantation: new insights from the autopsy room for an old but re‐emerging disease
Authors: Duarte‐Neto Amaro N , Cunha Marielton dos P , Marcilio Izabel , Song Alice T W , de Martino Rodrigo B , Ho Yeh‐Li , Pour Shahab Z , Dolhnikoff Marisa , Saldiva Paulo H N , Duarte Maria I S , Takakura Cleusa F , Lima Fabiana R , Tanigawa Ryan Y , Iglezias Silvia D’A , Kanamura Cristina T , dos Santos Angela B G , Perondi Beatriz , Zanotto Paolo M de A , D’Albuquerque Luiz A C , Alves Venancio A F 
Published: May 2019

AimsThe clinical spectrum of yellow fever (YF) ranges from asymptomatic to fulminant hepatitis. During the sylvatic YF epidemic in the metropolitan area of São Paulo, Brazil in 2018, seven orthotopic liver transplantations (OLTs) were performed in our institution to treat fulminant YF hepatitis. Three patients recovered, while four patients died following OLT. The autopsy findings of all these cases are presented herein as the first description of YF in transplanted patients.Methods and resultsAll patients were men, aged 16–40 years, without vaccination to YF virus (YFV). All organs were examined, with tissue sampling for histopathological analysis. Detection of YF virus antigens (YFV Ag) was performed with two primary antibodies (mouse polyclonal anti‐YFV antibody directed to wild strain and a goat anti‐YF virus antibody), and RT–PCR assays were utilised to detect YFV‐RNA. All the cases depicted typical findings of YF hepatitis in the engrafted liver. The main extrahepatic findings were cerebral oedema, pulmonary haemorrhage, pneumonia, acute tubular necrosis and ischaemic/reperfusion pancreatitis. Of the four cases, the YVF Ag was detected in the heart in one case, liver and testis in three cases, and the kidney and spleen in all four cases. All four cases had YF virus RNA detected by RT–PCR in the liver and in other organs.ConclusionsInfection of the engrafted liver and other organs by YFV, possibly combined with major ischaemic systemic lesions, may have led to the death of four of the seven patients undergoing OLT.
Changes in epidermal morphology associated with dandruff
Authors: Pople J. E. , Bhogal R. K. , Moore A. E. , Jenkins G. 
Published: May 2019

AbstractObjectiveDandruff is a very common scalp condition characterized by flaking and pruritus usually with no visible signs of inflammation, such as redness and erythema. Dandruff is considered a multifactorial condition with both microbial colonization and host factors such as sebum production thought to play a role. There is evidence of changes in epidermal morphology in the scalp skin of dandruff sufferers, with reports of an increase in mean thickness and more nucleated cell layers. The underlying mechanisms driving these morphological changes are currently unclear. The objective of this study was to fully characterize epidermal morphology in dandruff compared to healthy scalp skin and to evaluate potential mechanisms underlying any changes observed.MethodsScalp skin biopsies were taken from 22 healthy female subjects and 21 dandruff sufferers, from both lesional and non‐lesional sites. Samples were processed, sectioned and stained using haematoxylin and eosin (H&E). To fully characterize epidermal morphology, measurements were taken of epidermal thickness, the convolution of the dermal‐epidermal junction and the depth of epidermal rete ridges. To analyse changes in epidermal proliferation immunohistochemical staining was performed using Ki67, a well‐established marker of cell proliferation, and quantified using image analysis.ResultsHistochemical analysis of skin sections revealed that in dandruff lesional samples, the epidermis was thicker, had a more convoluted dermal epidermal junction and the rete ridges were elongated, compared to healthy scalp skin. Similar directional changes in epidermal morphology, were observed in non‐lesional dandruff samples, albeit to a lesser extent. Image analysis of Ki67 expression in the epidermis revealed dandruff lesional skin contained significantly more Ki67‐positive proliferating keratinocytes than healthy controls samples. This suggests dandruff scalp skin epidermal keratinocytes are in a hyper‐proliferative state.ConclusionThere were significant changes in epidermal morphology in dandruff lesional skin compared to healthy scalp skin including increased epidermal thickness, a more convoluted dermal‐epidermal junction and elongation of rete ridges. Interestingly, we found there was evidence of an increase in the percentage of epidermal Ki67‐positive cells, which has not been reported previously, and demonstrates dandruff is a condition displaying epidermal hyper‐proliferation.
Formation of α/β‐Si3N4nanoparticles by carbothermal reduction and nitridation of geopolymers
Authors: Bagci Cengiz , Yang Qun , Kriven Waltraud M. 
Published: May 2019

AbstractSilicon nitride (Si3N4) particles with various α/β‐Si3N4ratios were fabricated from geopolymer (GP)‐carbon compositions (M2O·Al2O3·4.5SiO2·12H2O+18C), where M is an alkali ion (Na+, K+and Cs+). They were made by carbothermal reduction and nitridation at 1400°, 1500°, and 1600°C for 2 hours under flowing nitrogen. Characterization of carbothermally reacted GP‐carbon compositions was based on XRD, SEM‐EDS, HRTEM, and selected area electron diffraction analyses. Depending on the alkaline composition of GP, the carbon content and the reaction temperature, a compositionally variable α/β‐Si3N4or SiAlON was achieved. Crystallization of the GPs gradually increased by heat treatment over 1400°C with corresponding weight loss. It was found that NaGP, KGP, and CsGP crystallized into a major phase of α‐Si3N4, β‐Si3N4, and SiAlON, respectively. Prolonged heating at 1600°C led to an increase in the α/β‐Si3N4ratio in NaGP due to the formation of aluminum nitride, while it led to a decrease in α/β‐Si3N4ratio in KGP. In the case of CsGP, SiAlON replaced the pollucite which mainly formed at lower temperatures. Transmission electron microscopy revealed that the needle‐like particles were of ~0.5 µm in size and consisting of α/β‐Si3N4mixtures.
Preparation and mechanical properties of Si3N4 nanocomposites reinforced by Si3N4@rGO particles
Authors: Hu Yangyang , Chen Zhaoqiang , Zhang Jingjie , Xiao Guangchun , Yi Mingdong , Zhang Wenliang , Xu Chonghai 
Published: May 2019

AbstractA new type of reduced graphene oxide‐encapsulated silicon nitride (Si3N4@rGO) particle was synthesized via an electrostatic interaction between amino‐functionalized Si3N4 particles and graphene oxide (GO). Subsequently, the Si3N4@rGO particles were incorporated into a Si3N4 matrix as a reinforcing phase to prepare nanocomposites, and their influence on the microstructure and mechanical properties of the Si3N4 ceramics was investigated in detail. The microstructure analysis showed that the rGO sheets were uniformly distributed throughout the matrix and firmly bonded to the Si3N4 grains to form a three‐dimensional carbon network structure. This unique structure effectively increased the contact area and load transfer efficiency between the rGO sheets and the matrix, which in turn had a significant impact on the mechanical properties of the nanocomposites. The results showed that the nanocomposites with 2.25 wt.% rGO sheets exhibited mechanical properties that were superior to monolithic Si3N4; the flexural strength increased by 83.5% and reached a maximum value of 1116.4 MPa, and the fracture toughness increased by 67.7% to 10.35 MPa·m1/2.
Does Mandatory Shareholder Voting Prevent Bad Acquisitions? The Case of the United Kingdom
Authors: Becht Marco , Polo Andrea , Rossi Stefano 
Published: May 2019

A large number of studies have shown that many companies have made large acquisitions that their own shareholders probably would not have approved if given the opportunity to do so. In this article, which summarizes the findings of their study published recently in the Review of Financial Studies, the authors present evidence that suggests the effectiveness of shareholder voting as a corporate governance mechanism designed to prevent such value‐reducing acquisitions from taking place.The authors' study focused on acquisitions in the U.K. where proposed transactions that exceed a series of 25% relative size (target's as a percentage of the acquirer's) thresholds are defined as “Class 1” transactions and require shareholder approval. The authors found strikingly positive stock market reactions to the announcements of such Class 1 acquisitions—as compared to zero if not negative average announcement returns for Class 2 transactions that were not subject to a shareholder vote. And when the authors extended their analysis to U.S. M&A markets, they found that the larger (again, in relative size) U.S. deals—large enough that they would have required a shareholder vote in the U.K.—provided returns to their shareholders that were negative, and thus significantly lower than those of their U.K counterparts. In terms of the economic significance of their findings, the authors found that Class 1 transactions were associated with aggregate gains to acquirer shareholders of $13.6 billion. By contrast, U.S. transactions of similar size, which again were not subject to shareholder approval, were associated with aggregate losses of $210 billion for acquirer shareholders; and Class 2 U.K. transactions, also not subject to shareholder approval, were associated with aggregate losses of $3 billion.In a further series of tests designed to shed light on how mandatory shareholder voting generates such substantial value improvements for acquirer shareholders, the authors also found evidence suggesting that when faced with the requirement of a shareholder vote, CEOs and boards are more likely to resist the temptation to overpay to close a deal. And the fact that the shareholders of the Class 1 acquirers did not end up blocking a single transaction that was submitted to a vote suggests that this mechanism works without the need for shareholders to actually vote down a deal. In other words, mandatory shareholder voting on acquisitions is a powerful deterrent to “bad deals” because, first of all, the vote is triggered automatically by the relative size tests and, second, CEOs and boards, with the help of their bankers, have a pretty good idea well in advance of the vote whether their shareholders are going to vote “no”—and such a vote would be viewed by top management as a major rejection, a strong vote of no confidence.