bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct Isolation of Seamless Mutant Bacterial Artificial Chromosomes
Authors: Lyozin George T. , Kosaka Yasuhiro , Bhattacharje Gourab , Yost H. Joseph , Brunelli Luca 
Published: April 2017

AbstractSeamless (i.e., without unwanted DNA sequences) mutant bacterial artificial chromosomes (BACs) generated via recombination‐mediated genetic engineering (recombineering) are better suited to study gene function compared to complementary DNA (cDNA) because they contain only the specific mutation and provide all the regulatory sequences required for in vivo gene expression. However, precisely mutated BACs are typically rare (∼1:1,000 to 1:100,000), making their isolation quite challenging. Although these BACs have been classically isolated by linking the mutation to additional genes, i.e., selectable markers, this approach is prone to false positives and is labor‐intensive because it requires the subsequent removal of the selectable marker. We created Founder Principle–driven Enrichment (FPE), a method based on the population genetics “founder principle,” to directly isolate rare mutant BACs, without any selectable marker, from liquid cultures via the polymerase chain reaction (PCR). Here, we provide a detailed description of FPE, including protocols for BAC recombineering and PCR screening. © 2017 by John Wiley & Sons, Inc.
Measuring Protein Interactions by Optical Biosensors
Authors: Zhao Huaying , Boyd Lisa F. , Schuck Peter 
Published: April 2017

AbstractThis unit gives an introduction to the basic techniques of optical biosensing for measuring equilibrium and kinetics of reversible protein interactions. Emphasis is placed on description of robust approaches that will provide reliable results with few assumptions. How to avoid the most commonly encountered problems and artifacts is also discussed. © 2017 by John Wiley & Sons, Inc.
Stakeholder Engagement and Corporate Social Responsibility (CSR) Performance: International Evidence
Authors: Lopatta Kerstin , Jaeschke Reemda , Chen Chen 
Published: April 2017

AbstractThis study examines the impact of stakeholder engagement in the form of controlling shareholders on the corporate social responsibility (CSR) performance of firms using data from 25 countries. The results show that there is a positive relation between state‐controlled ownership and the CSR performance of firms, whereas the other types of controlling ownership have no impact on CSR performance. Further results show that evidence is more pronounced in countries with more stakeholder engagement. Additional analysis indicates that the change of state controlled firms leads to a change in CSR performance, but not vice versa. Taken together, this paper highlights the importance of governmental ownership in shaping firms' corporate social responsibility performance in an international context. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment
Spray‐Dried Sodium Zirconate: A Rapid Absorption Powder for CO2 Capture with Enhanced Cyclic Stability
Authors: Bamiduro Faith , Ji Guozhao , Brown Andy P. , Dupont Valerie A. , Zhao Ming , Milne Steven J. 
Published: April 2017

AbstractImproved powders for capturing CO2 at high temperatures are required for H2 production using sorption‐enhanced steam reforming. Here, we examine the relationship between particle structure and carbonation rate for two types of Na2ZrO3 powders. Hollow spray‐dried microgranules with a wall thickness of 100–300 nm corresponding to the dimensions of the primary acetate‐derived particles gave about 75 wt % theoretical CO2 conversion after a process‐relevant 5 min exposure to 15 vol % CO2. A conventional powder prepared by solid‐state reaction carbonated more slowly, achieving only 50 % conversion owing to a greater proportion of the reaction requiring bulk diffusion through the densely agglomerated particles. The hollow granular structure of the spray‐dried powder was retained postcarbonation but chemical segregation resulted in islands of an amorphous Na‐rich phase (Na2CO3) within a crystalline ZrO2 particle matrix. Despite this phase separation, the reverse reaction to re‐form Na2ZrO3 could be achieved by heating each powder to 900 °C in N2 (no dwell time). This resulted in a very stable multicycle performance in 40 cycle tests using thermogravimetric analysis for both powders. Kinetic analysis of thermogravimetric data showed the carbonation process fits an Avrami–Erofeyev 2 D nucleation and nuclei growth model, consistent with microstructural evidence of a surface‐driven transformation. Thus, we demonstrate that spray drying is a viable processing route to enhance the carbon capture performance of Na2ZrO3 powder.
Catalytic Cracking of Lactide and Poly(Lactic Acid) to Acrylic Acid at Low Temperatures
Authors: Terrade Frédéric G. , van Krieken Jan , Verkuijl Bastiaan J. V. , Bouwman Elisabeth 
Published: April 2017

AbstractDespite being a simple dehydration reaction, the industrially relevant conversion of lactic acid to acrylic acid is particularly challenging. For the first time, the catalytic cracking of lactide and poly(lactic acid) to acrylic acid under mild conditions is reported with up to 58 % yield. This transformation is catalyzed by strong acids in the presence of bromide or chloride salts and proceeds through simple SN2 and elimination reactions.
Progranulin regulates neurogenesis in the developing vertebrate retina
Authors: Walsh Caroline E. , Hitchcock Peter F. 
Published: April 2017

ABSTRACTWe evaluated the expression and function of the microglia‐specific growth factor, Progranulin‐a (Pgrn‐a) during developmental neurogenesis in the embryonic retina of zebrafish. At 24 hpf pgrn‐a is expressed throughout the forebrain, but by 48 hpf pgrn‐a is exclusively expressed by microglia and/or microglial precursors within the brain and retina. Knockdown of Pgrn‐a does not alter the onset of neurogenic programs or increase cell death, however, in its absence, neurogenesis is significantly delayed—retinal progenitors fail to exit the cell cycle at the appropriate developmental time and postmitotic cells do not acquire markers of terminal differentiation, and microglial precursors do not colonize the retina. Given the link between Progranulin and cell cycle regulation in peripheral tissues and transformed cells, we analyzed cell cycle kinetics among retinal progenitors following Pgrn‐a knockdown. Depleting Pgrn‐a results in a significant lengthening of the cell cycle. These data suggest that Pgrn‐a plays a dual role during nervous system development by governing the rate at which progenitors progress through the cell cycle and attracting microglial progenitors into the embryonic brain and retina. Collectively, these data show that Pgrn‐a governs neurogenesis by regulating cell cycle kinetics and the transition from proliferation to cell cycle exit and differentiation. © 2017 The Authors. Developmental Neurobiology Published by Wiley Periodicals, Inc. Develop Neurobiol 77: 1114–1129, 2017
Human and natural controls of the variation in aboveground tree biomass in African dry tropical forests
Authors: Pelletier Johanne , Siampale Abel , Legendre Pierre , Jantz Patrick , Laporte Nadine T. , Goetz Scott J. 
Published: April 2017

AbstractUnderstanding the anthropogenic and natural controls that affect the patterns, distribution, and dynamics of terrestrial carbon is crucial to meeting climate change mitigation objectives. We assessed the human and natural controls over aboveground tree biomass density in African dry tropical forests, using Zambia's first nationwide forest inventory. We identified predictors that best explain the variation in biomass density, contrasted anthropogenic and natural sites at different spatial scales, and compared sites with different stand structure characteristics and species composition. In addition, we evaluated the effects of different management and conservation practices on biomass density. Variation in biomass density was mostly determined by biotic processes, linked with both species richness and dominance (evenness), and to a lesser extent, by land use, environmental controls, and spatial structure. Biomass density was negatively associated with tree species evenness and positively associated with species richness for both natural and human‐modified sites. Human influence variables (including distance to roads, distance to town, fire occurrence, and the population on site) did not explain substantial variation in biomass density in comparison to biodiversity variables. The relationship of human activities to biomass density in managed sites appears to be mediated by effects on species diversity and stand structure characteristics, with lower values in human‐modified sites for all metrics tested. Small contrasts in carbon density between human‐modified and natural forest sites signal the potential to maintain carbon in the landscape inside but also outside forestlands in this region. Biodiversity is positively related to biomass density in both human and natural sites, demonstrating potential synergies between biodiversity conservation and climate change mitigation. This is the first evidence of positive outcomes of protected areas and participatory forest management on carbon storage at national scale in Zambia. This research shows that understanding controls over biomass density can provide policy relevant inputs for carbon management and on ecological processes affecting carbon storage.
Advances in methods for estimating stopover duration for migratory species using capture–recapture data
Authors: Guérin S. , Picard D. , Choquet R. , Besnard A. 
Published: April 2017

AbstractMany species are migratory, resulting in a life cycle divided into periodic stages occurring in different habitats occupied for a limited amount of time. Estimating the time spent in each habitat is crucial to understanding how individuals modulate their activities and thus to evolutionary ecology and conservation biology. Several methods, including some recent promising advances, can be used to estimate stopover duration as well as arrival and departure probabilities at sites where individuals are monitored using capture–recapture sampling. Our objectives in this study were to (1) describe the available models to estimate stopover duration, (2) illustrate with an original data set what kinds of questions can be addressed using the most recent methods, and (3) to provide in a detailed appendix a practical guide for implementing these methods in E‐SURGEsoftware. To illustrate the potential of these models for testing biological hypotheses, we used a capture–recapture data set on marbled newts (Triturus marmoratus). We used time‐dependent and time‐elapsed‐since‐arrival effects (using both Markovian and semi‐Markov processes for the latter) to model stopover duration and the probability of arriving in and departing from a breeding pond for this species and compared the relative performance of the resulting models. Our findings showed a strong sex effect on stopover duration: females stayed on average 5.63 weeks in a breeding pond whereas males stayed only 3.03 weeks. In both sexes, the retention probability was mainly influenced by the time already spent there. Consequently, individuals of the same sex stayed a similar amount of time in a pond, although they did not arrive simultaneously but successively. The selected data set demonstrated the flexibility of these methods and their potential relevance for applications in evolutionary ecology and conservation.
Measurement invariance of the Eating Disorder Examination in black and white children and adolescents
Authors: Burke Natasha L. , Tanofsky‐Kraff Marian , Crosby Ross , Mehari Rim D. , Marwitz Shannon E. , Broadney Miranda M. , Shomaker Lauren B. , Kelly Nichole R. , Schvey Natasha A. , Cassidy Omni , Yanovski Susan Z. , Yanovski Jack A. 
Published: April 2017

AbstractObjectiveThe Eating Disorder Examination (EDE) was originally developed and validated in primarily white female samples. Since data indicate that eating pathology impacts black youth, elucidating the psychometric appropriateness of the EDE for black youth is crucial.MethodsA convenience sample was assembled from seven pediatric obesity studies. The EDE was administered to all youth. Confirmatory factor analyses (CFA) were conducted to examine the original four‐factor model fit and two alternative factor structures for black and white youth. With acceptable fit, multiple‐group CFAs were conducted. For measurement invariant structures, the interactive effects of race with sex, BMIz, adiposity, and age were explored (all significance levels p < .05).ResultsFor both black and white youth (N = 820; 41% black; 37% male; 6–18 years; BMIz −3.11 to 3.40), the original four‐factor EDE structure and alternative eight‐item one‐factor structure had mixed fit via CFA. However, a seven‐item, three‐factor structure reflecting Dietary Restraint, Shape/Weight Overvaluation, and Body Dissatisfaction had good fit and held at the level of strict invariance. Girls reported higher factor scores than boys. BMIz and adiposity were positively associated with each subscale. Age was associated with Dietary Restraint and Body Dissatisfaction. The interactional effects between sex, BMIz, and age with race were not significant; however, the interaction between adiposity and race was significant. At higher adiposity, white youth reported greater pathology than black youth.ConclusionAn abbreviated seven‐item, three‐factor version of the EDE captures eating pathology equivalently across black and white youth. Full psychometric testing of the modified EDE factor structure in black youth is warranted.
Landscape diversity and crop vigor outweigh influence of local diversification on biological control of a vineyard pest
Authors: Wilson Houston , Miles Albie F. , Daane Kent M. , Altieri Miguel A. 
Published: April 2017

AbstractThe influence of local and landscape habitat diversification on biological control of the Western grape leafhopper (Erythroneura elegantula Osborn) by its key parasitoids Anagrus erythroneurae S. Trjapitzin & Chiappini and Anagrus daanei Triapitsyn was studied in wine grape vineyards. At the landscape scale, Anagrus rely on alternative host species in non‐crop habitats outside of the vineyard to successfully overwinter, while at the local scale vineyard diversification can provide resources, such as shelter and floral nectar, which improve parasitoid performance. In a two‐year experiment, plots with and without flowering cover crops were compared in vineyards representing a gradient of landscape diversity. While the cover crops did attract natural enemies, their populations were unchanged in the crop canopy and there was no difference in parasitism rate, leafhopper density, crop quality, or yield. Vineyards in diverse landscapes had higher early‐season abundance of Anagrus spp., which was linked to increased parasitism and decreased late‐season populations of E. elegantula. Leafhopper densities were also positively associated with crop vigor, regardless of landscape or cover crops. Flowering cover crops did increase abundance of some natural enemy species as well as parasitism rate in vineyard landscapes with intermediate levels of diversity, indicating a local × landscape interaction, although this did not lead to reductions in E. elegantula densities. These findings indicate that, in this agroecosystem, landscape diversity mediates and in many ways outweighs the influence of local diversification and that E. elegantula densities were regulated by a combination of biological control and crop vigor.
The implications of American chestnut reintroduction on landscape dynamics and carbon storage
Authors: Gustafson Eric J. , de Bruijn Arjan , Lichti Nathanael , Jacobs Douglass F. , Sturtevant Brian R. , Foster Jane , Miranda Brian R. , Dalgleish Harmony J. 
Published: April 2017

AbstractIn the eastern United States, American chestnut (Castanea dentata) was historically a major component of forest communities, but was functionally extirpated in the early 20th century by an introduced pathogen, chestnut blight (Cryphonectria parasitica). Because chestnut is fast‐growing, long‐lived, and resistant to decay, restoration of American chestnut using blight‐resistant stock could have the potential to increase carbon sequestration or storage in forested landscapes. However, carbon dynamics are also affected by interspecific competition, succession, natural disturbance, and forest management activities, and it is unknown how chestnut restoration might interact with these other processes. We used the PnET‐Succession extension of theLANDIS‐IIforest landscape model to study the implications of chestnut restoration on forest composition and carbon storage in the context of other disturbances, including timber harvest and insect pest outbreaks. Our results imply that it could take a millennium or more for chestnut to fully occupy landscapes without aggressive restoration efforts. When successful, chestnut restoration activities displaced other species approximately in proportion to their abundance on the landscape, rather than replacing a single species or genus (e.g.,Quercus). Insect pests increased the rate of chestnut colonization by reducing the abundance of competitors, and also had a dominant effect on carbon dynamics. Although chestnut is fast‐growing, moderately shade‐tolerant, and decomposes very slowly, our results suggest that it can only modestly increase the carbon storage potential of eastern forests. However, our results also demonstrate that compositional changes in forest communities can have noticeable effects on biomass accumulation, even with the large uncertainties introduced by invasive pests.
Spacing behaviors and spatial recruitment of a wild rodent in response to parasitism
Authors: Shaner Pei‐Jen L. , Yu Ai‐Yun , Ke Linghua , Li Shou‐Hsien 
Published: April 2017

AbstractHost spacing may benefit the parasites (e.g., enhance parasite transmission) or the hosts (e.g., reduce host infection), with profound consequences in epidemiology and host–parasite dynamics. In this study, we tested parasitism effects of intestinal nematodes on spacing behaviors and spatial recruitment of the Taiwan field mouse (Apodemus semotus). We tracked the locations of resident mice for 84% of the host population, with half of them experimentally reduced of their parasitic infection. We interpolated geo‐tagged data on parasite egg counts of the resident mice to create an infection risk landscape and extracted the risks to the locations of newly recruited mice. We performed parentage analysis to identify mother–offspring pairs, which allowed us to test whether in situ recruits moved toward lower‐risk areas during natal dispersal. We found that the less‐infected mice became spatially aggregated compared to the more heavily infected, and the juvenile recruits occurred preferentially in lower‐risk areas compared to the landscape, the residents, and their natal places. The spatial aggregation of less‐infected resident mice and the association of juvenile recruits with lower‐risk areas could hinder parasite transmission. This study provided some empirical support for a potential link between host recruitment process and parasitism risks.
Consistently inconsistent drivers of microbial diversity and abundance at macroecological scales
Authors: Hendershot John Nicholas , Read Quentin D. , Henning Jeremiah A. , Sanders Nathan J. , Classen Aimée T. 
Published: April 2017

AbstractMacroecology seeks to understand broad‐scale patterns in the diversity and abundance of organisms, but macroecologists typically study aboveground macroorganisms. Belowground organisms regulate numerous ecosystem functions, yet we lack understanding of what drives their diversity. Here, we examine the controls on belowground diversity along latitudinal and elevational gradients. We performed a global meta‐analysis of 325 soil communities across 20 studies conducted along temperature and soil pH gradients. Belowground taxa, whether bacterial or fungal, observed along a given gradient of temperature or soil pH were equally likely to show a linear increase, linear decrease, humped pattern, trough‐shaped pattern, or no pattern in diversity along the gradient. Land‐use intensity weakly affected the diversity‐temperature relationship, but no other factor did so. Our study highlights disparities among diversity patterns of soil microbial communities. Belowground diversity may be controlled by the associated climatic and historical contexts of particular gradients, by factors not typically measured in community‐level studies, or by processes operating at scales that do not match the temporal and spatial scales under study. Because these organisms are responsible for a suite of key processes, understanding the drivers of their distribution and diversity is fundamental to understanding the functioning of ecosystems.
Precipitation affects plant communication and defense
Authors: Pezzola Enrico , Mancuso Stefano , Karban Richard 
Published: April 2017

AbstractAnti‐herbivore defense shows high levels of both inter‐ and intraspecific variability. Defending against herbivores may be costly to the plant when it requires a tradeoff in allocation between defense and other missed opportunities, such as reproduction. Indeed, the plastic expression of defensive traits allows the plant to invest resources in defense only when the risk of being damaged actually increases, avoiding wasted resources. Plants may assess risk by responding to volatile cues emitted by neighbors that are under attack. Most plastic responses likely depend on environmental conditions. In this experiment, we investigated the effect of water availability on resistance induced by volatile cues in sagebrush. We found that plants receiving additional water over summer and/or volatile cues from neighbor donor plants showed reduced herbivore damage compared to control plants. Interestingly, we found no evidence of interactions between additional water and volatile cues. We performed an inferential analysis comparing historical records of the levels of herbivore damage during different years that had different temperature and precipitation accumulations. Results confirmed findings from the experiment, as the regression model indicated that sagebrush was better defended during wetter and hotter seasons. Reports from the literature indicated that sagebrush is extremely sensitive to water availability in the soil. We suggest that water availability may directly affect resistance of herbivory as well as sensitivity to cues of damage. Costs and benefits of allocating resources to defensive traits may vary with environmental conditions.
Adult mortality in a low‐density tree population using high‐resolution remote sensing
Authors: Kellner James R. , Hubbell Stephen P. 
Published: April 2017

AbstractWe developed a statistical framework to quantify mortality rates in canopy trees observed using time series from high‐resolution remote sensing. By timing the acquisition of remote sensing data with synchronous annual flowering in the canopy tree species Handroanthus guayacan, we made 2,596 unique detections of 1,006 individual adult trees within 18,883 observation attempts on Barro Colorado Island, Panama (BCI) during an 11‐yr period. There were 1,057 observation attempts that resulted in missing data due to cloud cover or incomplete spatial coverage. Using the fraction of 123 individuals from an independent field sample that were detected by satellite data (109 individuals, 88.6%), we estimate that the adult population for this species on BCI was 1,135 individuals. We used a Bayesian state‐space model that explicitly accounted for the probability of tree detection and missing observations to compute an annual adult mortality rate of 0.2%·yr−1 (SE = 0.1, 95% CI = 0.06–0.45). An independent estimate of the adult mortality rate from 260 field‐checked trees closely matched the landscape‐scale estimate (0.33%·yr−1, SE = 0.16, 95% CI = 0.12–0.74). Our proof‐of‐concept study shows that one can remotely estimate adult mortality rates for canopy tree species precisely in the presence of variable detection and missing observations.