bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacterial phytopathogen infection disrupts belowground plant indirect defense mediated by tritrophic cascade
Authors: Rivera Monique J. , Pelz‐Stelinski Kirsten S. , Martini Xavier , Stelinski Lukasz L. 
Published: May 2017

AbstractPlants can defend themselves against herbivores through activation of defensive pathways and attraction of third‐trophic‐level predators and parasites. Trophic cascades that mediate interactions in the phytobiome are part of a larger dynamic including the pathogens of the plant itself, which are known to greatly influence plant defenses. As such, we investigated the impact of a phloem‐limited bacterial pathogen, Candidatus Liberibacter asiaticus (CLas), in cultivated citrus rootstock on a well‐studied belowground tritrophic interaction involving the attraction of an entomopathogenic nematode (EPN), Steinernema diaprepesi, to their root‐feeding insect hosts, Diaprepes abbreviatus larvae. Using belowground olfactometers, we show how CLas infection interferes with this belowground interaction by similarly inducing the release of a C12 terpene, pregeijerene, and disconnecting the association of the terpene with insect presence. D. abbreviatus larvae that were not feeding but in the presence of a CLas‐infected plant were more likely to be infected by EPN than those near uninfected plants. Furthermore, nonfeeding larvae associated with CLas‐infected plants were just as likely to be infected by EPN as those near noninfected plants with D. abbreviatus larval damage. Larvae of two weevil species, D. abbreviatus and Pachnaeus litus, were also more attracted to plants with infection than to uninfected plants. D. abbreviatus larvae were most active when exposed to pregeijerene at a concentration of 0.1 μg/μl. We attribute this attraction to CLas‐infected plants to the same signal previously thought to be a herbivore‐induced plant volatile specifically induced by root‐feeding insects, pregeijerene, by assessing volatiles collected from the roots of infected plants and uninfected plants with and without feeding D. abbreviatus. Synthesis. Phytopathogens can influence the structuring of soil communities extending to the third trophic level. Field populations of EPN may be less effective at host‐finding using pregeijerene as a cue in citrus grove agroecosystems with high presence of CLas infection.
Past, current, and future trends of red spiny lobster based on PCA with MaxEnt model in Galapagos Islands, Ecuador
Authors: Moya Wladimir , Jacome Gabriel , Yoo ChangKyoo 
Published: May 2017

AbstractIn order to enhance in terms of accuracy and predict the modeling of the potential distribution of species, the integration of using principal components of environmental variables as input of maximum entropy (MaxEnt) has been proposed in this study. Principal components selected previously from the principal component analysis results performed in ArcGIS in the environmental variables was used as an input data of MaxEnt instead of raw data to model the potential distribution of red spiny lobster from the year 1997 to 2015 and for three different future scenarios 2020, 2050, and 2070. One set of six original environmental variables pertaining to the years 1997–2015 and one set of four variables for future scenarios were transformed independently into a single multiband raster in ArcGIS in order to select the variables whose eigenvalues explains more than 5% of the total variance with the purpose to use in the modeling prediction in MaxEnt. The years 1997 and 1998 were chosen to compare the accuracy of the model, showing better results using principal components instead of raw data in terms of area under the curve and partial receiver operating characteristic as well as better predictions of suitable areas. Using principal components as input of MaxEnt enhances the prediction of good habitat suitability for red spiny lobster; however, future scenarios suggest an adequate management by researches to elaborate appropriate guidelines for the conservation of the habitat for this valuable specie with face to the climate change.
Tropical insect diversity: evidence of greater host specialization in seed‐feeding weevils
Authors: Peguero Guille , Bonal Raúl , Sol Daniel , Muñoz Alberto , Sork Victoria L. , Espelta Josep M. 
Published: May 2017

AbstractHost specialization has long been hypothesized to explain the extraordinary diversity of phytophagous insects in the tropics. However, addressing this hypothesis has proved challenging because of the risk of over‐looking rare interactions, and hence biasing specialization estimations, and the difficulties to separate the diversity component attributable to insect specialization from that related to host diversity. As a result, the host specialization hypothesis lacks empirical support for important phytophagous insect clades. Here, we test the hypothesis in a radiation of seed‐feeding insects, acorn weevils (Curculio spp.), sampled in temperate and tropical regions (California and Nicaragua, respectively) with an equivalent pool of oak host species. Using DNA sequences from three low‐copy genes, we delimited to species level 778 weevil larvae extracted from host seeds and assessed their phylogenetic relationships by Maximum Likelihood and Bayesian inference. We then reconstructed the oak‐weevil food webs and examined differences in alpha, beta and gamma diversity using Hill numbers of effective species. We found a higher alpha, beta and gamma diversity of weevils in Nicaragua compared to California despite similar richness of host species at both local and regional level. By means of Bayesian mixed models, we also found that tropical weevil species were highly specialized both in terms of host range and interaction strength, whereas their temperate congeners had a broader taxonomic and phylogenetic host spectrum. Finally, in Nicaraguan species, larval body size was highly correlated with the size of the acorns infested, as would be expected by a greater host specialization, whereas in California this relationship was absent. Altogether, these lines of evidence support the host specialization hypothesis and suggest contrasting eco‐evolutionary dynamics in tropical and temperate regions even in absence of differences in host diversity.
Local density regulates migratory songbird reproductive success through effects on double‐brooding and nest predation
Authors: Woodworth Bradley K. , Wheelwright Nathaniel T. , Newman Amy E. M. , Norris D. Ryan 
Published: May 2017

AbstractKnowledge of the density‐dependent processes that regulate animal populations is key to understanding, predicting, and conserving populations. In migratory birds, density‐dependence is most often studied during the breeding season, yet we still lack a robust understanding of the reproductive traits through which density influences individual reproductive success. We used 27‐yr of detailed, individual‐level productivity data from an island‐breeding population of Savannah sparrows Passerculus sandwichensis to evaluate effects of local and total annual population density on female reproductive success. Local density (number of neighbors within 50 m of a female's nest) had stronger effects on the number of young fledged than did total annual population density. Females nesting in areas of high local density were more likely to suffer nest predation and less likely to initiate and fledge a second clutch, which led to fewer young fledged in a season. Fledging fewer young subsequently decreased the likelihood of a female recruiting offspring into the breeding population in a subsequent year. Collectively, these results provide insight into the scale and reproductive mechanisms mediating density‐dependent reproductive success and fitness in songbirds.
Spontaneous CD4+ and CD8+ T‐cell responses directed against cancer testis antigens are present in the peripheral blood of testicular cancer patients
Authors: Pearce Hayden , Hutton Paul , Chaudhri Shalini , Porfiri Emilio , Patel Prashant , Viney Richard , Moss Paul 
Published: May 2017

Cancer/testis antigen (CTAg) expression is restricted to spermatogenic cells in an immune‐privileged site within the testis. However, these proteins are expressed aberrantly by malignant cells and T‐cell responses against CTAgs develop in many cancer patients. We investigated the prevalence, magnitude and phenotype of CTAg‐specific T cells in the blood of patients with testicular germ cell tumors (TGCTs). CD8+ and CD4+ T‐cell responses against MAGE‐A family antigens were present in 44% (20/45) of patients’ samples assayed by ex vivo IFN‐γ ELISPOT. The presence of MAGE‐specific CD8+ T cells was further determined following short‐term in vitro expansion through the use of pMHC‐I multimers containing known immunogenic peptides. Longitudinal analysis revealed that the frequency of MAGE‐specific T cells decreased by 89% following orchidectomy suggesting that persistence of tumor antigen is required to sustain CTAg‐specific T‐cell immunity. Notably, this decrease correlated with a decline in the global effector/memory T‐cell pool following treatment. Spontaneous T‐cell immunity against CTAg proteins therefore develops in many patients with testicular cancer and may play an important role in the excellent clinical outcome of patients with this tumor subtype.
Factors controlling soil erosion and runoff and their impacts in the upper Wissey catchment, Norfolk, England: A ten year monitoring programme
Authors: Evans Robert 
Published: May 2017

AbstractMonitoring of runoff and erosion in farmers' fields and their impacts gives a better understanding of erosion. However, it is rare that monitoring at frequent intervals is done over a prolonged period. A part of the upper Wissey catchment in central Norfolk, eastern England was monitored for 10 years to assess the extent and frequency of erosion and runoff, their causes and impacts. Surface wash occurred more widely and more frequently than expected. Runoff and erosion took place a number of times in a year in a range of autumn‐ and spring‐sown crops, and occurred dominantly down tractor wheelings or ruts left after harvesting potatoes or sugar beet under wet conditions. Over 10 years erosion affected about half the 105 fields monitored, often more than once. Erosion was more extensive in autumn‐sown cereal fields, but often more severe and with greater off‐field effects, for example muddy flooding of roads from spring‐sown late harvested crops such as potatoes and sugar beet. Runoff from outdoor pig fields also flooded roads and houses. This study confirms other studies of the extent, frequency and severity of erosion in Britain, that rill erosion does not occur in every field in the landscape, that in the main, fields do not erode frequently and rates of erosion are generally small. Runoff and erosion within a field took place more frequently than had been suspected. Compaction and destruction of topsoil structure by machinery especially at harvest, or by outdoor pigs, is important in initiating runoff. Rates of erosion were generally very low and will not affect soil productivity adversely over the short‐term. However, flooding of roads and property, and especially pollution of water courses by sediment, nutrients and pesticides are important off‐field impacts and are the primary reason, over the short‐term, for mitigating runoff and erosion. Monitoring such as this sheds light on the problems of modelling to predict risk of erosion based on erosion rates. Copyright © 2017 John Wiley & Sons, Ltd.
Study of using aluminum hypophosphite as a flame retardant for low‐density polyethylene
Authors: Tian Shenghui , He Hui , Wang Dekang , Yu Peng , Jia Yunchao , Luo Yuanfang 
Published: May 2017

AbstractAluminum hypophosphite (AHP) was first used to improve the flame retardance of low‐density polyethylene (LDPE). The flame‐retardant properties of LDPE composites were investigated by the limiting oxygen index, vertical burning test (UL‐94), microscale combustion calorimetry, and cone calorimeter tests. The results showed that the incorporation of AHP could improve the flame retardancy of LDPE dramatically, the limiting oxygen index of LDPE containing 50 phr AHP reached 27.5%, and the UL‐94 could pass V‐0 rating. The cone calorimeter test results indicated that PP/AHP composite exhibited superior performance, and the heat release rate and the total heat release of composites were significantly reduced. In addition, the strength of the char was improved with the load of AHP increased. The structure of the char was researched by Fourier transform infrared spectrometry (FTIR) and scanning electron microscope‐energy dispersive spectrometer, and the results revealed that AHP promoted the formation of compact char layer. The TG‐FTIR analyses proved that AHP could react with LDPE to reduce the production of olefin in gas phase. Moreover, the structure of P–O–C was found, and the effective mechanism of AHP in LDPE composites was also hypothesized in this work.
Research Methodology in Global Strategy Research
Authors: Cuervo‐Cazurra Alvaro , Mudambi Ram , Pedersen Torben , Piscitello Lucia 
Published: May 2017

Research summaryWe review advances in research methodology used in global strategy research and provide suggestions on how researchers can improve their analyses and arguments. Methodological advances in the extraction of information, such as computer‐aided text analysis, and in the analysis of datasets, such as differences‐in‐differences and propensity score matching, have helped deal with challenges (e.g., endogeneity and causality) that bedeviled earlier studies and resulted in conflicting findings. These methodological advances need to be considered as tools that complement theoretical arguments and well‐explained logics and mechanisms so that researchers can provide better and more relevant recommendations to managers designing the global strategies of their organizations.Managerial summaryWe review advances in research methodology used in global strategy research and provide suggestions for improving researchers’ analyses and arguments. Methodological advances in the extraction of information and in the analysis of datasets have helped researchers deal with challenges that bedeviled earlier studies and resulted in conflicting findings. These advances have provided researchers with the ability to obtain valid, unbiased results with clear and relevant managerial implications. Such methodological advances need to be considered as tools that complement theoretical arguments and well‐explained logics and mechanisms so that researchers can provide better and more relevant recommendations to managers designing the global strategies of their organizations. Copyright © 2017 Strategic Management Society.
Robust rankings of socioeconomic health inequality using a categorical variable
Authors: Makdissi Paul , Yazbeck Myra 
Published: May 2017

AbstractWhen assessing socioeconomic health inequalities, researchers often draw upon measures of income inequality that were developed for ratio scale variables. As a result, the use of categorical data (such as self‐reported health status) produces rankings that may be arbitrary and contingent to the numerical scale adopted. In this paper, we develop a method that overcomes this issue by providing conditions for which these rankings are invariant to the numerical scale chosen by the researcher. In doing so, we draw on the insight provided by Allison and Foster (2004) and extend their method to the dimension of socioeconomic inequality by exploiting the properties of rank‐dependent indices such as Wagstaff (2002) achievement and extended concentration indices. We also provide an empirical illustration using the National Institute of Health Survey 2012.
GSK3 activity regulates rhythms in hippocampal clock gene expression and synaptic plasticity
Authors: Besing Rachel C. , Rogers Courtney O. , Paul Jodi R. , Hablitz Lauren M. , Johnson Russell L. , McMahon Lori L. , Gamble Karen L. 
Published: May 2017

AbstractHippocampal rhythms in clock gene expression, enzymatic activity, and long‐term potentiation (LTP) are thought to underlie day–night differences in memory acquisition and recall. Glycogen synthase kinase 3‐beta (GSK3β) is a known regulator of hippocampal function, and inhibitory phosphorylation of GSK3β exhibits region‐specific differences over the light‐dark cycle. Here, we sought to determine whether phosphorylation of both GSK3α and GSK3β isoforms has an endogenous circadian rhythm in specific areas of the hippocampus and whether chronic inhibition or activation alters the molecular clock and hippocampal plasticity (LTP). Results indicated a significant endogenous circadian rhythm in phosphorylation of GSK3β, but not GSK3α, in hippocampal CA1 extracts from mice housed in constant darkness for at least 2 weeks. To examine the importance of this rhythm, genetic and pharmacological strategies were used to disrupt the GSK3 activity rhythm by chronically activating or inhibiting GSK3. Chronic activation of both GSK3 isoforms in transgenic mice (GSK3‐KI mice) diminished rhythmic BMAL1 expression. On the other hand, chronic treatment with a GSK3 inhibitor significantly shortened the molecular clock period of organotypic hippocampal PER2::LUC cultures. While WT mice exhibited higher LTP magnitude at night compared to day, the day–night difference in LTP magnitude remained with greater magnitude at both times of day in mice with chronic GSK3 activity. On the other hand, pharmacological GSK3 inhibition impaired day–night differences in LTP by blocking LTP selectively at night. Taken together, these results support the model that circadian rhythmicity of hippocampal GSK3β activation state regulates day/night differences in molecular clock periodicity and a major form of synaptic plasticity (LTP).
Climate teleconnections influence on West Africa's terrestrial water storage
Authors: Ndehedehe Christopher E. , Awange Joseph L. , Kuhn Michael , Agutu Nathan O. , Fukuda Yoichi 
Published: May 2017

AbstractThere is some evidence of rapid changes in the global atmosphere and hydrological cycle caused by the influence of climate variability. In West Africa, such changes impact directly on water resources leading to incessant extreme hydro‐meteorological conditions. This study examines the association of three global climate teleconnections—El‐Niño Southern Oscillation (ENSO), Indian Ocean Dipole (IOD), and Atlantic Multi‐decadal Oscillation (AMO) with changes in terrestrial water storage (TWS) derived from both Modern‐Era Retrospective Analysis for Research and Applications (MERRA, 1980–2015) and Gravity Recovery and Climate Experiment (GRACE, 2002–2014). In the Sahel region, positive phase of AMO coincided with above‐normal rainfall (wet conditions) and the negative phase with drought conditions and confirms the observed statistically significant association (r = 0.62) between AMO and the temporal evolutions of standardised precipitation index. This relationship corroborates the observed presence of AMO‐driven TWS in much of the Sahel region (though considerably weak in some areas). Although ENSO appears to be more associated with GRACE‐derived TWS over the Volta basin (r=−0.40), this study also shows a strong presence of AMO‐ and ENSO‐induced TWS derived from MERRA reanalysis data in the coastal West African countries and most of the regions below latitude 10°N. The observed presence of ENSO‐ and AMO‐driven TWS is noticeable in tropical areas with relatively high annual/bimodal rainfall and strong inter‐annual variations in surface water. The AMO has a wider footprint and sphere of influence on the region's TWS and suggests the important role of North Atlantic Ocean. IOD‐related TWS also exists in West Africa and its influence on the region's hydrology maybe secondary and somewhat complementary. Nonetheless, presumptive evidence from the study indicates that ENSO and AMO are the two major climatic indices more likely to impact on West Africa's TWS.
Conjunctiva derived mesenchymal stem cell (CJMSCs) as a potential platform for differentiation into corneal epithelial cells on bioengineered electrospun scaffolds
Authors: Soleimanifar Fatemeh , Mortazavi Yousef , Nadri Samad , Soleimani Masoud 
Published: May 2017

AbstractWith the aid of tissue engineering, the capability of nanofibrous scaffolds was examined for corneal epithelial differentiation of Conjunctiva mesenchymal stem cells (CJMSCs) as a new source. This study tried to provide a synthetic corneal sheet which could be applied in corneal regeneration. The hybrid arrangement of fine Silk fibers with the diameter of 93.65 nm and the polyurethane (PU) fibers with an average diameter of 575.5 makes a mat with sufficient mechanical properties and interconnected pores that could accelerate nutrient diffusion. After methanol and plasma treatment, the highest biocompatibility of Silk‐PU hybrid nanofibrous scaffolds based on cell attachment and proliferation were proven using MTT assay. The differentiation morphology of cells was observed by SEM micrographs of cells seeded on the scaffold after 12 days treatment through the differentiation medium. Despite up‐regulation of Cytokeratin (CK)3, CK8, CK12, Desmocollin (DSC)1, and Desmoglein (DSG)1 in the treated PU and silk hybrid nanofibrous scaffolds, the relative expression of CK3, CK8, and CK12 genes were highest among TCP, treated PU and silk nanofibrous scaffolds. Immunocytochemistry (ICC) analysis was used to characterize the protein expression of CK3 in CJ‐MSCs seeded on different groups. Although, For both TCP and hybrid group, CJ‐MSCs were positive for corneal epithelial‐specific marker CK3, ICC data demonstrated that CJ‐MSCs seeded on the hybrid group likewise PU or Silk pure nanofibrous scaffolds, could differentiate into corneal epithelial‐like cells. Finally, it was inferred that the hybrid PU and silk nanofibrous scaffold has the potential for the treatment of corneal epithelium. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2703–2711, 2017.
Effect of recombinant human bone morphogenic protein 9 (rhBMP9) loaded onto bone grafts versus barrier membranes on new bone formation in a rabbit calvarial defect model
Authors: Fujioka‐Kobayashi Masako , Kobayashi Eizaburo , Schaller Benoit , Mottini Matthias , Miron Richard J. , Saulacic Nikola 
Published: May 2017

AbstractRecent research has demonstrated that recombinant human bone morphogenetic protein 9 (rhBMP9) has been considered the most osteoinductive growth factor of the BMP‐family. In the present study, rhBMP9 was investigated for its influence in combination with two biomaterials for bone regenerative medicine. Either porcine‐derived collagen membrane (CM) or deproteinized bovine bone mineral (DBM) combined with 20 µg of rhBMP9 were implanted in 6 mm rabbit calvarial defects. Bone augmentation was evaluated by microCT and histomorphometry at 8 weeks post‐surgery. Both CM + rhBMP9 and DBM + rhBMP9 groups significantly promoted mineralized tissue volume (microCT) and area, new bone height and area (histomorphometric measurements) when compared to CM and DBM alone groups or control (empty). All specimens in the CM + rhBMP9 group but not all in the DBM + rhBMP9 group induced a complete horizontal bone defect closure. Multinucleated giant cells (MNGCs) were observed directly in contact with DBM surfaces irrespective of rhBMP9, whereas CM was generally not associated to the presence of MNGCs. When combined with rhBMP9, DBM augmented a larger volume of mineralized tissue (including the mineralized bone graft), whereas CM induced greater volume of native host bone. While DBM in combination with rhBMP9 induced higher mineralized tissue mostly associated with the bone grafting material, CM may have presented preferable results based on a higher horizontal defect closure with a faster regeneration of host new bone. The effect of including collagen within the carrier system of rhBMP9 on bone regeneration justifies further evaluation of this combination procedure in larger animal models. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2655–2661, 2017.