bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure and Functional Binding Epitope of V-domain Ig Suppressor of T-cell Activation (VISTA)
Authors: Mehta Nishant , Maddineni Sainiteesh , Mathews Irimpan I. , Sperberg Andres Parra , Huang Po-Ssu , Cochran Jennifer R.
Published: April 2019

V-domain Ig Suppressor of T cell Activation (VISTA) is an immune checkpoint protein that inhibits the T - cell response against cancer. Similar to PD-1 and CTLA-4, antibodies that block VISTA signaling can release the brakes of the immune system and promote tumor clearance. VISTA has an Ig-like fold, but little is known about its structure and mechanism of action. Here, we report a 1.85 Å crystal structure of the human VISTA extracellular domain and highlight structural features that make VISTA unique among B7 family members. Through fine-epitope mapping, we also identify solvent-exposed residues that underlie binding to a clinically relevant anti-VISTA antibody. This antibody-binding region is also shown to interact with V-set and Ig domain-containing 3 (VSIG3), the recently proposed functional binding partner of VISTA. The structure and functional epitope determined here will help guide future drug development efforts against this important checkpoint target.
Y-chromosome haplogroups from Hun, Avar and conquering Hungarian period nomadic people of the Carpathian Basin
Authors: Neparáczki Endre , Maróti Zoltán , Kalmár Tibor , Maár Kitti , Nagy István , Latinovics Dóra , Kustár Ágnes , Pálfi György , Molnár Erika , Marcsik Antónia , Balogh Csilla , Lőrinczy Gábor , Gál Szilárd Sándor , Tomka Péter , Kovacsóczy Bernadett , Kovács László , Raskó István , Török Tibor
Published: April 2019

Hun, Avar and conquering Hungarian nomadic groups arrived into the Carpathian Basin from the Eurasian Steppes and significantly influenced its political and ethnical landscape. In order to shed light on the genetic affinity of above groups we have determined Y chromosomal haplogroups and autosomal loci, from 49 individuals, supposed to represent military leaders. Haplogroups from the Hun-age are consistent with Xiongnu ancestry of European Huns. Most of the Avar-age individuals carry east Eurasian Y haplogroups typical for modern north-eastern Siberian and Buryat populations and their autosomal loci indicate mostly unmixed Asian characteristics. In contrast the conquering Hungarians seem to be a recently assembled population incorporating pure European, Asian and admixed components. Their heterogeneous paternal and maternal lineages indicate similar phylogeographic origin of males and females, derived from Central-Inner Asian and European Pontic Steppe sources. Composition of conquering Hungarian paternal lineages is very similar to that of Baskhirs, supporting historical sources that report identity of the two groups.
Brain imaging correlates of general intelligence in UK Biobank
Authors: Cox SR , Ritchie SJ , Fawns-Ritchie C , Tucker-Drob EM , Deary IJ
Published: April 2019

The associations between indices of brain structure and measured intelligence are not clear. In part, this is because the evidence to date comes from mostly small and heterogenous studies. Here, we report brain structure-intelligence associations on a large sample from the UK Biobank study. The overall N = 29,004, with N = 18,363 participants providing both brain MRI and cognitive data, and a minimum N = 7318 providing the MRI data alongside a complete four-test battery. Participants’ age range was 44-81 years (M = 63.13, SD = 7.48). A general factor of intelligence (g) was extracted from four varied cognitive tests, accounting for one third of the variance in the cognitive test scores. The association between (age-and sex-corrected) total brain volume and a latent factor of general intelligence is r = 0.275, 95% C.I. = [0.252, 0.299]. A model that incorporated multiple global measures of grey and white matter macro-and microstructure accounted for more than double the g variance in older participants compared to those in middle-age (13.4% and 5.9%, respectively). There were no sex differences in the magnitude of associations between g and total brain volume or other global aspects of brain structure. The largest brain regional correlates of g were volumes of the insula, frontal, anterior/superior and medial temporal, posterior and paracingulate, lateral occipital cortices, thalamic volume, and the white matter microstructure of thalamic and association fibres, and of the forceps minor.
The Long-run Effects of Secondary School Track Assignment
Authors: Borghans Lex , Diris Ron , Smits Wendy , de Vries Jannes
Published: April 2019

This study analyzes the long-run effects of secondary school track assignment for students at the achievement margin. Theoretically, track assignment maximizes individual outcomes when thresholds between tracks are set at the level of the indifferent student, and any other thresholds would imply that students at or around the margin are better off by switching tracks. We exploit non-linearities in the probability of track assignment across achievement to empirically identify the effect of track assignment on educational attainment and wages of students in the Netherlands, who can be assigned to four different tracks. We find that attending higher tracks leads to increases in years of schooling by around 1.5 years for students at the lowest and the highest choice margin, and wage gains of around 15% and 5%, respectively. Results at the margin of the two medium tracks show no effect on educational attainment, and decreases in wage of around 12% from attending the higher track. The negative returns for the medium margin and the relatively low returns for the higher margin (compared to the required educational investments) are partly mediated by motivation and study choice.
NF-YA Transcriptionally Activates the Expression of SOX2 in Cervical Cancer Stem Cells
Authors: Yang Wen-Ting , Zhao Zong-Xia , Li Bin , Zheng Peng-Sheng
Published: April 2019

Roles for SOX2 have been extensively studied in several types of cancer, including colorectal cancer, glioblastoma and breast cancer, with particular emphasis placed on the roles of SOX2 in cancer stem cell. Our previous study identified SOX2 as a marker in cervical cancer stem cells driven by a full promoter element of SOX2 EGFP reporter. Here, dual-luciferase reporter and mutagenesis analyses were employed, identifying key cis-elements in the SOX2 promoter, including binding sites for SOX2, OCT4 and NF-YA factors in SOX2 promoter. Mutagenesis analysis provided additional evidence to show that one high affinity-binding domain CCAAT box was precisely recognized and bound by the transcription factor NF-YA. Furthermore, overexpression of NF-YA in primitive cervical cancer cells SiHa and C33A significantly activated the transcription and the protein expression of SOX2. Collectively, our data identified NF-YA box CCAAT as a key cis-element in the SOX2 promoter, suggesting that NF-YA is a potent cellular regulator in the maintenance of SOX2-positive cervical cancer stem cell by specific transcriptional activation of SOX2.
How the liver contributes to stomach warming in the endothermic white sharkCarcharodon carcharias
Authors: Bernvi David C. , Cliff Geremy
Published: April 2019

Background

White sharks and other lamnids are able to elevate their stomach temperature. The ability to heat large amounts of food to the recorded levels of up to 17°C above the ambient water temperature can’t be explained only by the heat generated by catabolism and the endothermic adaptions of the suprahepatic rete. This rete has two shunts that regulates the volume of blood flowing from the liver to the sinus venosus, thereby providing a temperature control mechanism for the GIT. The liver’s function in this temperature regulation is unknown. White shark stomach volume is well above 135 l in sub-adults to accommodate large prey items, including marine mammals. The simultaneous ingestion of large volumes of cold water during feeding will result in marked cooling of the stomach. Our study investigated the role of the liver in relation to warming the gastro-intestinal tract and the retention of elevated core temperatures.

Materials and methods

The liver morphology and its position relative to the gastro-intestinal tract were investigated in 13 white sharksCarcharodon carcharias. Stomach volume and the thickness of the abdominal wall were also measured to give a comparative estimate of heat insulation by white muscles.

Results

In all white sharks examined the two liver lobes completely enveloped the entire gastrointestinal tract, with the anterio-ventral margins of the liver almost interlocking around the stomach. A large, conspicuous, flattened vascular system was only present on the inner surfaces of both liver lobes. The thickness of the ventral abdominal body wall is only 12% of that of the dorso-lateral body wall, so the potential for heat loss from the GIT via the belly region is high.

Conclusion

Our study builds on the findings of other researchers which revealed that the liver and digestive tract receive a major portion of their blood supply through the suprahepatic rete, which is a heat exchanger aimed at retaining metabolic heat generated by the red locomotory muscles. This heat is not only transferred to the stomach via its supply of warm blood but also via thermal conduction from the vessels on the inside of the liver, which envelopes the digestive tract and serves as a large reservoir of venous blood. The liver is rich in lipids, with insulatory properties to retain the heat which would otherwise be rapidly lost through the extremely thin ventral abdominal wall in temperate waters, where white sharks commonly occur. These findings provide insight into the hitherto unknown role played by the liver in the highly elevated stomach temperatures reported, thereby providing this endothermic top predator with enhanced rates of digestion.
Bone regeneration in Ds-Red pig calvarial defect using allogenic transplantation of EGFP-pMSCs – a comparison of host cells and seeding cells in the scaffold
Authors: Hsieh Ming-Kai , Wu Chia-Jung , Su Xuan-Chun , Chen Yi-Chen , Tsai Tsung-Ting , Niu Chi-Chien , Lai Po-Liang , Wu Shinn-Chih
Published: April 2019

Background

Cells, scaffolds, and factors are the triad of regenerative engineering; however, it is difficult to distinguish whether cells in the regenerative construct are from the seeded cells or host cells via the host blood supply. We performed a novel in vivo study to transplant enhanced green fluorescent pig mesenchymal stem cells (EGFP-pMSCs) into calvarial defect of DsRed pigs. The cell distribution and proportion were distinguished by the different fluorescent colors through the whole regenerative period.

Method/Results

Eight adult domestic Ds-Red pigs were treated with five modalities: empty defects without scaffold (group 1); defects ﬁlled only with scaffold (group 2); defects ﬁlled with osteoinduction medium-loaded scaffold (group 3); defects filled with 5 × 103 cells/scaffold (group 4); and defects filled with 5 × 104 cells/scaffold (group 5). The in vitro cell distribution, morphology, osteogenic differentiation, and ﬂuorescence images of groups 4 and 5 were analyzed. Two animals were sacriﬁced at 1, 2, 3, and 4 weeks after transplantation. The in vivo ﬂuorescence imaging and quantification data showed that EGFP-pMSCs were represented in the scaffolds in groups 4 and 5 throughout the whole regenerative period. A higher seeded cell density resulted in more sustained seeded cells in bone regeneration compared to a lower seeded cell density. Host cells were recruited by seeded cells if enough space was available in the scaffold. Host cells in groups 1 to 3 did not change from the 1st week to 4th week, which indicates that the scaffold without seeded cells cannot recruit host cells even when enough space is available for cell ingrowth. The histological and immunohistochemical data showed that more cells were involved in osteogenesis in scaffolds with seeded cells.

Conclusion

Our in vivo results showed that more seeded cells recruit more host cells and that both cell types participate in osteogenesis. These results suggest that scaffolds without seeded cells may not be effective in bone transplantation.
Modelling marine larval dispersal: a cautionary deep-sea tale for ecology and conservation
Authors: Ross Rebecca E. , Nimmo-Smith W. Alex M. , Torres Ricardo , Howell Kerry L.
Published: April 2019

Larval dispersal data are increasingly sought after in ecology and marine conservation, the latter often requiring information under time limited circumstances. Basic estimates of dispersal are often used in these situations acknowledging their oversimplified nature. Larval dispersal models (LDMs) are now becoming more popular and may be a tempting way of refining predictions, but prior to targeted groundtruthing their predictions are of unknown worth. This case study uses deep-sea LDMs to compare predictions of dispersal. Two LDMs driven by different example hydrodynamic models are compared, along with an informed estimate based on mean current speed and planktonic larval duration (PLD) to provide insight into predictive variability. LDMs were found to be more conservative in dispersal distance than an estimate. This difference increased with PLD which may result in a bigger disparity for deep-sea species predictions. Although LDMs were more spatially targeted than an estimate, the two LDM predictions were also significantly different from each other and would result in contrasting advice for marine conservation. These results show a greater potential for model variability than previously appreciated by ecologists and strongly advocates groundtruthing predictions before use in management. Advice is offered for improved model selection and interpretation of predictions.
Epigenetic gestational age and trajectories of weight and height during childhood: a prospective cohort study
Authors: Bright Harold D. , Howe Laura D. , Khouja Jasmine N. , Simpkin Andrew J. , Suderman Matthew , O’Keeffe Linda M.
Published: April 2019

Background

Differences between an individual’s estimated epigenetic gestational age (EGA) and their actual gestational age (GA) are defined as gestational age acceleration (GAA). GAA is associated with increased birthweight and birth length. Whether these associations persist through childhood is yet to be investigated.

Methods

We examined the association between GAA and trajectories of height and weight from birth to 10 years (n=785) in a British birth cohort study, the Avon Longitudinal Study of Parents and Children (ALSPAC). EGA of participants was estimated using DNA methylation data from cord blood using a recently-developed prediction model. GA of participants was gathered in ALSPAC from clinical records and was measured from last menstrual period (LMP) for most participants. GAA of participants, measured in weeks, was calculated as the residuals from a regression model of EGA on actual GA. Height and weight were obtained from several sources including birth records, research clinics, routine child health clinics, links to health visitor records and parent-reported measures from questionnaires. Analyses were performed using linear spline multilevel models and adjusted for maternal age, maternal pre-pregnancy BMI, maternal smoking during pregnancy and maternal education.

Results

In adjusted analyses, offspring with a one-week greater GAA were born on average 0.14 kg heavier (95% Confidence Interval (CI) 0.09, 0.19) and 0.55 cm taller (95% CI 0.33, 0.78) at birth. These differences in weight persisted up to approximately age 9 months but thereafter began to attenuate and reduce in magnitude. From age 5 years onwards, the association between GAA and weight reversed such that GAA was associated with lower weight and this association strengthened with age (mean difference at age 10 years −0.60 kg (95% CI, −1.19, −0.01)). Differences in height persisted only up to age 9 months (mean difference at 9 months 0.15 cm, (95% CI −0.09, 0.39)). From age 9 months to age 10 years, offspring with a one-week greater GAA were of comparable height to those with no GAA (mean difference at age 10 years −0.07 cm, (95% CI −0.64, 0.50)).

Conclusions

Gestational age acceleration is associated with increased birth weight and length and these differences persist to age 9 months. From 5 years onwards, the association of GAA and weight reverses such that by age 10 years greater GAA is associated with lower childhood weight. Further work is required to examine whether the weight effects of GAA strengthen further through adolescence and into early adulthood.
Ccr4–Not maintains genomic integrity by controlling the ubiquitylation and degradation of arrested RNAPII
Authors: Jiang Haoyang , Wolgast Marley , Beebe Laura M. , Reese Joseph C.
Published: April 2019

The Ccr4–Not complex regulates essentially every aspect of gene expression, from mRNA synthesis to protein destruction. The Not4 subunit of the complex contains an E3 RING domain and targets proteins for ubiquitin-dependent proteolysis. Ccr4–Not associates with elongating RNA polymerase II (RNAPII), which raises the possibility that it controls the degradation of elongation complex components. Here, we demonstrate that Ccr4–Not controls the ubiquitylation and turnover of Rpb1, the largest subunit of RNAPII, during transcription arrest. Deleting NOT4 or mutating its RING domain strongly reduced the DNA damage-dependent ubiquitylation and destruction of Rpb1. Surprisingly, in vitro ubiquitylation assays indicate that Ccr4–Not does not directly ubiquitylate Rpb1 but instead promotes Rpb1 ubiquitylation by the HECT domain-containing ligase Rsp5. Genetic analyses suggest that Ccr4–Not acts upstream of RSP5, where it acts to initiate the destruction process. Ccr4–Not binds Rsp5 and forms a ternary complex with it and the RNAPII elongation complex. Analysis of mutant Ccr4–Not lacking the RING domain of Not4 suggests that it both recruits Rsp5 and delivers the E2 Ubc4/5 to RNAPII. Our work reveals a previously unknown function of Ccr4–Not and identifies an essential new regulator of RNAPII turnover during genotoxic stress.
High-resolution crystal structures of the glycoside hydrolase family 45 endoglucanase EG27II from the snailAmpullaria crossean
Authors: Nomura Taisuke , Iwase Hisamu , Saka Naoki , Takahashi Nobuyuki , Mikami Bunzo , Mizutani Kimihiko
Published: April 2019

Although endogenous animal cellulases have great potential for industrial applications such as bioethanol production, few investigations have focused on these enzymes. In this study, the glycoside hydrolase family 45 (GH45) subfamily B endoglucanase EG27II from the snailAmpullaria crosseanwas expressed using aPichia pastorisexpression system and the crystal structure of the apo form was determined at 1.00 Å resolution; this is the highest resolution structure of an animal endoglucanase. The results showed that EG27II has a double-ψ six-stranded β-barrel and that the structure of EG27II more closely resembles those of subfamily C enzymes than those of subfamily A enzymes. The structure of EG27II complexed with cellobiose was also determined under cryoconditions and at room temperature at three pH values, pH 4.0, 5.5 and 8.0, and no structural changes were found to be associated with the change in pH. The structural comparison and catalytic activity measurements showed that Asp137 and Asn112 function as the catalytic acid and base, respectively, and that Asp27 is also an important residue for catalysis. These high-resolution structures of EG27II provide a large amount of information for structure-based enzyme modification and cell-surface engineering, which will advance biofuel production using animal-derived cellulases.
Effects of climate change and grazing pressure on shrub communities of West Asian rangelands
Authors: Louhaichi Mounir , Ouled Belgacem Azaiez , Petersen Steven L. , Hassan Sawsan
Published: April 2019

Purpose

The purpose of this study is to evaluate the vulnerability of the important rangeland shrub,Atriplex leucoclada(Boiss) to both climate change and livestock grazing, within the Syrian rangelands as a representative landscape type of West Asia.

Design/methodology/approach

Ecologically based quantitative niche models were developed for both shrub species using maximum entropy and 13 spatially explicit GIS-based layers to predict current and future species distribution scenarios. Climatic variables varied over time in line with the predictions created from the HADCM3 global circulation model.

Findings

Results indicate that with grazing and climate change, the distribution ofA. leucocladawill be reduced by 54 per cent in 2050, with the mean annual and minimum temperatures of the coldest month having the highest contribution in the model (28.7 and 21.2 per cent, respectively). The contribution of the grazing pressure, expressed by the overgrazing index, was estimated at 8.2 per cent.

Originality/value

These results suggest that the interaction of climate and increased grazing has the potential to favor the establishment of unpalatable species, while reducing the distribution of preferred plant species on western Asia rangelands.
Contributions of path-dependency and social capital drivers to housing tenure transitions in Britain
Authors: Aguda Oluwadamilola
Published: April 2019

Purpose

The purpose of this paper is to investigate the contributions of path-dependency and some contextual social capital drivers to housing tenure transitions in Britain. Different situations have continued to shape young adults’ housing tenure decisions. However, very little research has been done to investigate the impact of some social capital drivers, such as neighbourhood integration and strength of parental intimacy, on housing tenure decisions in Britain.

Design/methodology/approach

This paper is carried out by tracking a sample of young adults in the British Household Panel Survey from 1991 to 2015 until they make tenure transition. Multinomial fixed-effects logistic regression of time to tenure transition was useful for the models, incorporating established economic and demographic drivers and with the inclusion of contextual social capital variables.

Findings

The inclusion of the number of years of parental home ownership experience tends to improve on previous path-dependency indicators of tenure transition. With additional years of parental home ownership experience, British young adults are more likely to remain or return to parental housing. Also, individuals that exchange better with their neighbours are less likely to switch tenure. On the other hand, regularity of contact with parents showed a positive relationship with home ownership or parental housing transitions.

Originality/value

To the best of the author’s knowledge, no study has explored the impact of the duration of socialisation in parental housing and also the impact of some other social capital drivers, such as neighbourhood integration and strength of parental intimacy, on housing tenure decisions among young adults. Hence, it is believed that the findings will further assist policymakers in understanding the dimensions and drivers of tenure shifts.
Political will and public will for climate-smart agriculture in Senegal
Authors: Raile Eric D. , Young Linda M. , Sarr Adama , Mbaye Samba , Raile Amber N.W. , Wooldridge Lena , Sanogo Diaminatou , Post Lori Ann
Published: April 2019

Purpose

Agriculture must transform as climate change progresses. The international community has promoted climate-smart agriculture (CSA) as a set of solutions. Previous analyses of opportunities for scaling up CSA have not looked closely at building political and social support for policies, practices and programs. The purpose of this paper is to fill that gap in the case study country of Senegal.

Design/methodology/approach

The study applies the conceptual definitions, operationalizations and assessment targets from the political will and public will (PPW) approach to social change. Semi-structured interviews and documents constitute the sources of data and information.

Findings

The analysis identifies opportunities to generate political will for supplying an enabling environment for the widespread adoption of CSA. On the public will side, the analysis identifies opportunities to generate and channel demand for CSA.

Research limitations/implications

Researchers investigated some definitional components more completely than others due to resource and access constraints. Further, the context specificity of the components limits generalizability of certain findings.

Social implications

Social structures may need to change for successful adoption of certain CSA innovations, but improved agricultural outcomes are likely to result.

Originality/value

This examination of crucial elements for scaling up CSA efforts constitutes the most extensive application of the PPW approach to date, thus providing an example of this generalizable method.
Self-censorship in social networking sites (SNSs) – privacy concerns, privacy awareness, perceived vulnerability and information management
Authors: Warner Mark , Wang Victoria
Published: April 2019

Purpose

This paper aims to investigate behavioural changes related to self-censorship (SC) in social networking sites (SNSs) as new methods of online surveillance are introduced. In particular, it examines the relationships between SC and four related factors: privacy concerns (PC), privacy awareness (PA), perceived vulnerability (PV) and information management (IM).

Design/methodology/approach

A national wide survey was conducted in the UK (N= 519). The data were analysed to present both descriptive and inferential statistical findings.

Findings

The level of online SC increases as the level of privacy concern increases. The level of privacy concern increases as the levels of PA and PV increase and the level of effective IM decreases.

Originality/value

This study extends the literature on online SC, showing that PCs increase the level of SC in SNSs. It provides support for three antecedent factors to PC which impact upon levels of SC when communicating in SNSs.
Adoption of e-Governance
Authors: Khanra Sayantan , Joseph Rojers P.
Published: April 2019

Purpose

This study aims to investigate India’s poor performance in the overall implementation of e-Governance despite significant improvements in the quality and scope of e-Government services in the country.

Design/methodology/approach

The study proposes a conceptual model based on four hypotheses that are tested using the structural equation modeling technique. Based on the results obtained, the conceptual model is suitably modified.

Findings

The major finding of the study is that “English proficiency” and “digital divide” sequentially mediate the relationship between “service quality” and the “willingness to adopt e-Governance” in India.

Research limitations/implications

The conceptual model emerging from the study adds to the literature on e-Governance service quality and adoption. However, a longitudinal or experimental study may provide more insights into the context.

Practical implications

Primarily, this study would interest agencies involved in developing and delivering e-Governance services. Besides, the findings may be useful for the “big data companies” that are interested in gaining direct access to the last-mile users of developing countries.

Social implications

The study intends to provide directions to policymakers on improving access to e-Governance services for the people who are deprived of the benefits of such services.

Originality/value

This is the first study to incorporate both English proficiency and digital divide in a single conceptual model in the literature related to the relationship between service quality and the willingness to adopt e-Governance.
High-performance computer graphics technologies in engineering applications
Authors: Peng Chao
Published: April 2019

Purpose

The purpose of this paper is to investigate possibilities to adopt state-of-the-art computer graphics technologies for big data visualization in engineering applications. Toward this purpose, a conceptual heterogeneous system is proposed for graphical rendering, which is established with multiple central processing unit cores and multiple graphics processing unit GPUs.

Design/methodology/approach

The design of the system supports both general-purpose computation and graphics-related computation. Three processing components are discussed to fulfill the execution requirements in load balancing, data streaming and display. This design fully uses computational and memory resources and enhances the performance with the support of GPU-based parallelization.

Findings

The advantages and disadvantages of particular technical methods for each processing component are discussed. The possible ways to integrate them are analyzed.

Originality/value

This work has contributions of using computer graphics technologies in engineering applications.
The decline in plant biodiversity slows down soil carbon turnover under increasing nitrogen deposition in a temperate steppe
Authors: Yang Sen , Liu Weixing , Qiao Chunlian , Wang Jing , Deng Meifeng , Zhang Beibei , Liu Lingli
Published: April 2019

Nitrogen (N) deposition not only alters the physiological processes of individual plant, but also leads to world‐wide biodiversity loss. However, little is known about how the hierarchical responses from individual physiological processes to plant community structure would have cascading effects on soil carbon (C) cycling.

Here, we assessed whether changes in plant chemical composition and community composition under increasing N input would affect the turnover rate of litter layer and soil C loss via heterotrophic respiration (Rh) in a temperate grassland.

We showed that more than a decade’s N addition significantly decreased plant species richness, litter layer turnover rate and Rh. The 13C‐NMR results showed that, for individual species, N addition either increased the abundance of recalcitrant C groups such as alkyl and methoxyl, or decreased labile C groups such as carbohydrate, resulting in decreases in carbohydrate C‐to‐methoxyl C ratio (CC/MC) for most species. Our data also showed that with the increase in N deposition, the abundance of relatively high degradable dominant species, such as Agropyron cristatum and Artimesia frigida declined rapidly, and the relatively recalcitrant species such as Potentilla bifurca and Leymus chinensis become dominant. Changes in individual species’ chemical composition and plant community composition significantly decreased litter quality at community level, as indicated by the lower community‐level CC/MC at higher N addition rates.

The result of step‐AIC model selection further showed that plant diversity loss and the decrease in community‐level CC/MC jointly explained the decrease in Rh after N addition best, and further relative importance partition result showed that these two factors respectively contributed 65.1% and 34.9% of the explained variation.

Overall, we demonstrated that changes in plant chemical composition and diversity loss due to N addition reduced the quality of plant C input to soil, which further slowed down litter layer turnover rate and inhibited soil heterotrophic respiration. Our study complements the intermediate links of how shifts in plant community structure regulate soil C cycle under global changes.

A plain language summary is available for this article.
Impacts of dead wood manipulation on the biodiversity of temperate and boreal forests. A systematic review
Authors: Sandström Jennie , Bernes Claes , Junninen Kaisa , Lõhmus Asko , Macdonald Ellen , Müller Jörg , Jonsson Bengt Gunnar
Published: April 2019

Dead wood (DW) provides critical habitat for thousands of species in forests, but its amount, quality and diversity have been heavily reduced by forestry. Therefore, interventions aiming to increase DW might be necessary to support its associated biodiversity, even in protected forests, which may be former production forests. Our aim was to synthesize the current state of knowledge drawn from replicated experimental studies into solid quantitative evidence of the effects of DW manipulation on forest biodiversity, with a focus on protected forests.

We conducted a full systematic review of effects of DW manipulation on forest biodiversity in boreal and temperate regions. We included three intervention types: creation of DW from live trees at the site, addition of DW from outside the site and prescribed burning. Outcomes included abundance and species richness of saproxylic insects, ground insects, wood‐inhabiting fungi, lichens, reptiles and cavity‐nesting birds. In total, we included 91 studies, 37 of which were used in meta‐analyses.

Although meta‐analysis outcomes were heterogeneous, they showed that increasing the amount of DW (“DW enrichment”) has positive effects on the abundance and richness of saproxylic insects and fungi. The positive effect on saproxylic pest insect abundance tended to be less than that on saproxylic insects in general. No significant effects were found for ground insects or cavity‐nesting birds.

Although reviewed studies were mainly short term, our results support that management that increases DW amounts has the potential to increase the abundance of DW‐dependent species and, in most cases, also their species richness. Studies of burning showed positive effects on the abundance of saproxylic insects similar to those of other interventions, even though burning on average resulted in a smaller enrichment of DW amounts.

Policy implications. The findings of the review suggest that manipulating dead wood (DW) can be an effective part of conservation management to support biodiversity in protected areas. The findings also indicate that the diversity of DW types is important, a mix of DW qualities should be favoured. Burning seems to be an effective method to increase biodiversity but to benefit cavity‐nesting birds, snag losses need to be minimized.
Functional diversity and composition of Caatinga woody flora are negatively impacted by chronic anthropogenic disturbance
Authors: Ribeiro Elâine M. S. , Lohbeck Madelon , Santos Braulio A. , Arroyo‐Rodríguez Víctor , Tabarelli Marcelo , Leal Inara R.
Published: April 2019

Tropical plant assemblages can be taxonomically and phylogenetically impoverished by chronic anthropogenic disturbance (CAD), such as firewood collection and extensive grazing. However, to what extent the functional dimension responds to CAD is still unclear. Such knowledge is urgently required for predicting, preventing or even reversing the impacts of CAD.

Chronic anthropogenic disturbance may operate as an ecological filter by selecting functional trait values (e.g. low wood density), thereby altering the functional composition and diversity of plant assemblages. We tested this hypothesis using 29 woody plant assemblages across three ontogenetic stages (seedlings, saplings and adults) in a 220‐km2 landscape of the Caatinga, northeast Brazil. We adopted a CAD index consisting of four indicators (proximity to urban centre and houses and the density of both people and livestock) and tested how well it explained the functional diversity and effect sizes (richness, evenness and dispersion) and composition (community‐weighted mean).

Chronic anthropogenic disturbance affected several functional metrics across the three ontogenetic stages. However, CAD effects were stronger in adult communities by negatively affecting functional richness, dispersion and their effect sizes. CAD also altered the functional composition of leaf mass per area, woody density and leaf area of adult assemblages. Sapling communities were affected in terms of functional composition (leaf area, leaf dry matter and wood density), with positive and negative effects, while seedling assemblages responded positively to CAD only in terms of functional evenness and its effect size. Some changes in functional metrics were influenced by dominant Euphorbiaceae species across ontogenetic stages, especially in terms of leaf area and woody density.

Synthesis. Chronic anthropogenic disturbance is an important driver of plant‐community functional organization across ontogenetic stages in the Caatinga. Adult assemblages are particularly sensitive and tend to lose functional niche space and support more acquisitive rather than conservative strategies as chronic anthropogenic disturbance increases. The proliferation of Euphorbiaceae disturbance‐adapted species can explain part of the community responses to chronic anthropogenic disturbance. Our findings highlight the ecological effects of chronic anthropogenic disturbance and show that it is a key influence on tropical biotas. Changes in plant functional traits associated with plant resource use are likely to affect ecosystem functioning and services provided by Caatinga.
Testing DNA barcodes against morphology for the ‘tripectinate Abantiades' (Lepidoptera: Hepialidae) reveals a complex relationship between COI sequence data and morphology
Authors: Simonsen Thomas J , Moore Michael D , Dupont Steen T , Stevens Mark I
Published: April 2019

We analyse COI sequence data from 140 specimens of the Australian ‘tripectinate‐Abantiades' to explore the group's molecular diversity and identify potential taxonomic challenges for future studies. A recent taxonomic revision raised the number of species in the group from three to 10. Our results generally agree with that study, but we identify further potential new species. However, our results also highlight the limitations of single gene taxonomic studies as some otherwise well‐defined species are non‐monophyletic in our analyses – in particular Abantiades argentata Tindale appears paraphyletic with respect to several other lineages, and may comprise more than one species. Overall, the mitochondrial COI diversity of the ‘tripectinate‐Abantiades' can be divided into three major groups, with a majority of the species found in the semi‐arid regions of South Australia and Western Australia.
Complexity, continuity and change: livelihood resilience in the Darfur region of Sudan
Authors: Young Helen , Ismail Musa Adam
Published: April 2019

Darfur farming and pastoralist livelihoods are both adaptations to the environmental variability that characterises the region. This article describes this adaptation and the longer‐term transformation of these specialised livelihoods from the perspective of local communities. Over several decades farmers and herders have experienced a continuous stream of climate, conflict and other shocks, which, combined with wider processes of change, have transformed livelihoods and undermined livelihood institutions. Their well‐rehearsed specialist strategies are now combined with new strategies to cope. These responses help people get by in the short term but risk antagonising not only their specialist strategies but also those of others. A combination of factors has undermined the former integration between farming and pastoralism and their livelihood institutions. Efforts to build resilience in similar contexts must take a long‐term view of livelihood adaptation as a specialisation, and consider the implications of new strategies for the continuity and integration of livelihood specialisations.
Resilience from the ground up: how are local resilience perceptions and global frameworks aligned?
Authors: Beauchamp Emilie , Abdella Jennifer , Fisher Susannah , McPeak John , Patnaik Hannah , Koulibaly Papa , Cissé Daouda , Touré Mamadou , Bocoum Aly , Ndao Momath , Deme Yacouba , Gueye Bara
Published: April 2019

Numerous resilience measurement frameworks for climate programmes have emerged over the past decade to operationalise the concept and aggregate results within and between programmes. Proxies of resilience, including subjective measures using perception data, have been proposed to measure resilience, but there is limited evidence on their validity and use for policy and practice. This article draws on research on the Decentralising Climate Funds project of the Building Resilience and Adaptation to Climate Extremes and Disasters programme, which supports communities in Mali and Senegal to improve climate resilience through locally controlled adaptation funds. It explores attributes of resilience from this bottom‐up perspective to assess its predictors and alignment with food security, as a proxy of well‐being. We find different patterns when comparing resilience and the well‐being proxy, illustrating that the interplay between the two is still unclear. Results also point to the importance of contextualising resilience, raising implications for aggregating results.
A CTOD equation based on the rigid rotational factor with the consideration of crack tip blunting due to strain hardening for SEN(B)
Authors: Khor WeeLiam
Published: April 2019

Crack tip opening displacement (CTOD) from national and international standards was shown to give different values. This paper investigates the feasibility of CTOD determined based on the concept of rigid rotational factor in single‐edge notched bend (SENB) specimens. Based on validated modelling methods, finite element (FE) models were simulated for crack ratios 0.3 ≤ a0/W ≤ 0.7 and yield‐to‐tensile ratio 0.44 ≤ σys/σuts ≤ 0.98. This covers cases of shallow to deeply cracked specimens and a wide range of strain hardening properties. CTOD obtained from the FE models was used as the basis of a newly implemented strain hardening corrected rotational factor, which considers the effects of crack tip blunting due to strain hardening, rp sh. An improved equation considering strain hardening was implemented based on the rp sh. The equation gives accurate estimation of CTOD from the FE models compared with the equation from BS 7448‐1, ASTM E1820, and WES 1180.
Sperm head abnormalities are more frequent in songbirds with more helical sperm: A possible trade‐off in sperm evolution
Authors: Støstad Hanna N. , Rowe Melissah , Johnsen Arild , Lifjeld Jan T.
Published: April 2019

Sperm morphology varies enormously across the animal kingdom. Whilst knowledge of the factors that drive the evolution of interspecific variation in sperm morphology is accumulating, we currently have little understanding of factors that may constrain evolutionary change in sperm traits. We investigated whether susceptibility to sperm abnormalities could represent such a constraint in songbirds, a group characterized by a distinctive helical sperm head shape. Specifically, using 36 songbird species and data from light and scanning electron microscopy, we examined among‐species correlations between the occurrence of sperm head abnormalities and sperm morphology, as well as the correlation between sperm head abnormalities and two indicators of sperm competition. We found that species with more helically shaped sperm heads (i.e., a wider helical membrane and more pronounced cell waveform) had a higher percentage of abnormal sperm heads than species with less helical sperm (i.e., relatively straight sperm) and that sperm head traits were better predictors of head abnormalities than total sperm length. In contrast, there was no correlation between sperm abnormalities and the level of sperm competition. Given that songbird species with more pronounced helical sperm have higher average sperm swimming speed, our results suggest an evolutionary trade‐off between sperm performance and the structural integrity of the sperm head. As such, susceptibility to morphological abnormalities may constrain the evolution of helical sperm morphology in songbirds.
Impact of high‐voltage electric discharge treatment on cocoa shell phenolic components and methylxanthines
Authors: Barišić Veronika , Flanjak Ivana , Križić Ivana , Jozinović Antun , Šubarić Drago , Babić Jurislav , Miličević Borislav , Ačkar Đurđica
Published: April 2019

Cocoa shell is one of the by‐products obtained in chocolate industry which was considered as waste for a very long time. Recently, the presence of high‐valuable bioactive components in cocoa shell was recognized, and research on the pallet of food products enriched with cocoa shell is increasing. The most abundant bioactive components of untreated cocoa shell (UCS) are theobromine (3.906 ± 0.070 mg/g), caffeine (0.646 ± 0.055 mg/g), and (+)‐catechin (0.290 ± 0.005 mg/g), followed by gallic acid (0.147 ± 0.041 mg/g) and (−)‐epicatechin (0.165 ± 0.099 mg/g). Furthermore, the impact of concentration (1.5 and 3% of cocoa shell in water), high‐voltage electric discharge (HVED) treatment (40 and 80 Hz), and treatment time (15, 30, and 45 min, respectively) on bioactive compounds content was evaluated. Statistically significant differences between treatment conditions were obtained. Generally, water‐HVED treatment at 40 Hz has lower impact on bioactive components than water, and water‐HVED at 80 Hz, therefore, can have a significant effect on future treatments of materials rich in bioactive compounds.

Practical applications

HVED is an innovative nonthermal processing technique that has mechanical and electrical effect on the product resulting with lower costs and increase of functional properties. This study has shown that HVED causes lower decrease of phenolics and methylxanthines in cocoa shell which can have a significant effect on future treatments of materials rich in bioactive compounds. Because it is not recorded in scientific literature that HVED treatment was used on cocoa shell so far, it will help in future research and applications of cocoa shell in the food industry.
A Problem‐Solving Intervention for Hospice Family Caregivers: A Randomized Clinical Trial
Authors: Demiris George , Oliver Debra Parker , Washington Karla , Pike Kenneth
Published: April 2019

OBJECTIVES

Family caregivers of hospice patients have multiple needs as they try to cope during a stressful time. Translatable interventions effective in improving caregiver outcomes are greatly needed. Our objective was to assess the impact of a problem‐solving intervention (called Problem‐Solving Intervention to Support Caregivers in End‐of‐Life Care Settings [PISCES]) to support hospice caregivers on caregiver quality of life and anxiety, and compare its effectiveness delivered face to face and via videoconferencing.

DESIGN

In this 4‐year randomized clinical trial, caregivers were randomly assigned to a group receiving standard care with added “friendly calls” (attention control [AC] group), a group receiving standard care and PISCES delivered face to face (F2F), or a group receiving standard care and PISCES delivered via videoconferencing (VC).

SETTING

Home hospice.

PARTICIPANTS

A total of 514 caregivers participated (172 in AC, 171 in F2F, and 171 in VC). Caregivers were predominantly female (75%); mean age was 60.3 years.

INTERVENTION

PISCES includes a structured curriculum delivered in three sessions and motivates caregivers to adopt a positive attitude, define problems by obtaining facts, set goals, and generate and evaluate solutions.

MEASUREMENTS

Quality of life was measured by the Caregiver Quality of Life Index‐Revised; anxiety was measured by the Generalized Anxiety Disorder 7‐Item. Other measures included the Caregiver Reaction Assessment scale, demographic data, and an exit interview.

RESULTS

Compared with AC, caregivers in the F2F condition had postintervention reduced anxiety (−1.31 [95% confidence interval [CI] = −2.11 to .50];p = .004) and improved social (.57 [95% CI = .19‐.95];p = .01), financial (.57 [95% CI = .21‐.93];p = .004), and physical quality of life (.53 [95% CI = .19‐.87];p = .01). There were no differences in caregivers in the VC condition compared with the AC condition.

CONCLUSION

The PISCES intervention improves caregiver outcomes and is effective when delivered in person. How to integrate technology to reduce the intervention delivery cost warrants further investigation.