bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacterial cellulose spheroids as building blocks for 2D and 3D engineered living materials
Authors: Caro-Astorga Joaquin , Walker Kenneth T. , Ellis Tom 
Published: May 2020

AbstractEngineered living materials (ELMs) based on bacterial cellulose (BC) offer a promising avenue for cheap-to-produce materials that can be programmed with genetically encoded functionalities. Here we explore how ELMs can be fabricated from millimetre-scale balls of cellulose occasionally produced byAcetobacteriaceaspecies, which we call BC spheroids. We define a reproducible protocol to produce BC spheroids and demonstrate their potential for use as building blocks to grow ELMs in 2D and 3D shapes. These BC spheroids can be genetically functionalized and used as the method to make and grow patterned BC-based ELMs to design. We further demonstrate the use of BC spheroids for the repair and regeneration of BC materials, and measure the survival of the BC-producing bacteria in the material over time. This work forwards our understanding of BC spheroid formation and showcases their potential for creating and repairing engineered living materials.
Genetic determinants of receptor-binding preference and zoonotic potential of H9N2 avian influenza viruses
Authors: Peacock Thomas P. , Sealy Joshua E. , Harvey William T. , Benton Donald J. , Reeve Richard , Iqbal Munir 
Published: May 2020

AbstractReceptor recognition and binding is the first step of viral infection and a key determinant of host specificity. The inability of avian influenza viruses to effectively bind human-like sialylated receptors is a major impediment to their efficient transmission in humans and pandemic capacity. Influenza H9N2 viruses are endemic in poultry across Asia and parts of Africa where they occasionally infect humans and are therefore considered viruses with zoonotic potential. We previously described H9N2 viruses, including several isolated from human zoonotic cases, showing a preference for human-like receptors. Here we take a mutagenesis approach, making viruses with single or multiple substitutions in H9 haemagglutinin to determine the genetic basis of preferences for alternative avian receptors and for human-like receptors. We describe amino acid motifs at positions 190, 226 and 227 that play a major role in determining receptor specificity, and several other residues such as 159, 188, 193, 196, 198 and 225 play a smaller role. Furthermore, we show changes at residues 135, 137, 147, 157, 158, 184, 188, and 192 can also modulate virus receptor avidity and that substitutions that increased or decreased the net positive charge around the haemagglutinin receptor-binding site show increases and decreases in avidity, respectively. The motifs we identify as increasing preference for the human-receptor will help guide future H9N2 surveillance efforts and facilitate our understanding of the emergence of influenza viruses with high zoonotic potential.Author SummaryAs of 2020, over 60 infections of humans by H9N2 influenza viruses have been recorded in countries were the virus is endemic. Avian-like cellular receptors are the primary target for these viruses. However, given that human infections have been detected on an almost monthly basis since 2015, there may be a capacity for H9N2 viruses to evolve and gain the ability to target human-like cellular receptors. Here we identify molecular signatures that can cause viruses to bind human-like receptors, and we identify the molecular basis for the distinctive preference for sulphated receptors displayed by the majority of recent H9N2 viruses. This work will help guide future surveillance by providing markers that signify the emergence of viruses with enhanced zoonotic potential as well as improving understanding the basis of influenza virus receptor-binding.
Rapid isolation of potent SARS-CoV-2 neutralizing antibodies and protection in a small animal model
Authors: Rogers Thomas F. , Zhao Fangzhu , Huang Deli , Beutler Nathan , Burns Alison , He Wan-ting , Limbo Oliver , Smith Chloe , Song Ge , Woehl Jordan , Yang Linlin , Abbott Robert K. , Callaghan Sean , Garcia Elijah , Hurtado Jonathan , Parren Mara , Peng Linghang , Ricketts James , Ricciardi Michael J. , Rawlings Stephen A. , Smith Davey M. , Nemazee David , Teijaro John R. , Voss James E. , Andrabi Raiees , Briney Bryan , Landais Elise , Sok Devin , Jardine Joseph G. , Burton Dennis R. 
Published: May 2020

ABSTRACTThe development of countermeasures to prevent and treat COVID-19 is a global health priority. In under 7 weeks, we enrolled a cohort of SARS-CoV-2-recovered participants, developed neutralization assays to interrogate serum and monoclonal antibody responses, adapted our high throughput antibody isolation, production and characterization pipeline to rapidly screen over 1000 antigen-specific antibodies, and established an animal model to test protection. We report multiple highly potent neutralizing antibodies (nAbs) and show that passive transfer of a nAb provides protection against high-dose SARS-CoV-2 challenge in Syrian hamsters. The study suggests a role for nAbs in prophylaxis, and potentially therapy, of COVID-19. The nAbs define protective epitopes to guide vaccine design.
Effects of seasonality and land use on the abundance and distribution of mosquitoes on St. Kitts, West Indies
Authors: Valentine Matthew J. , Ciraola Brenda , Jacobs Gregory R. , Arnot Charlie , Kelly Patrick J. , Murdock Courtney C. 
Published: May 2020

AbstractBackgroundHigh quality mosquito surveys that collect fine resolution local data on mosquito species’ abundances provide baseline data to help us understand potential host-pathogen-mosquito relationships, accurately predict disease transmission, and target mosquito control efforts in areas at risk of mosquito borne diseases.MethodsAs part of an investigation into arboviral sylvatic cycles on the Caribbean island of St. Kitts, we carried out an island wide mosquito survey from November 2017 to March 2019. Using Biogents Sentinel 2 and miniature CDC light traps that were set monthly and run for 48 hour intervals, we collected mosquitoes from a total of 30 sites distributed across the five common land covers on the island (agricultural, mangrove, rainforest, scrub, and urban). We developed a mixed effects negative binomial regression model to predict the effects of land cover, seasonality, and precipitation on observed counts of the most abundant mosquito species we found.ResultsWe captured 10 of the 14 mosquito species reported on the island, the four most abundant beingAedes taeniorhynchus, Culex quinquefasciatus, Aedes aegpyti, andDeinocerites magnus. Sampling in the mangroves yielded the most mosquitoes, withAe. taeniorhynchus, Cx. quinquefasciatus, andDe. magnuspredominating.Aedes aegyptiwas recovered primarily from urban and agricultural habitats, but also at lower frequency in other land covers.Psorophora pygmaeaandToxorhynchites guadeloupensiswere only captured in scrub habitat. Capture rates in rainforests were low. Our models indicated the relative abundance of the four most common species varied seasonally and with land cover. They also suggested that the extent to which monthly average precipitation influenced counts varied according to species.ConclusionsThis study demonstrates there is high seasonality in mosquito abundances and that land cover influenced the distribution and abundance of mosquito species on St. Kitts. Further, human-adapted mosquito species (e.g.Ae. aegyptiandCx. quinquefasciatus) that are known vectors for many human relevant pathogens are the most wide-spread (across land covers) and the least responsive to seasonal variation in precipitation.
Activation of the SARS-CoV-2 receptorAce2by cytokines through pan JAK-STAT enhancers
Authors: Hennighausen Lothar , Lee Hye Kyung 
Published: May 2020

SummaryACE2, in concert with the protease TMPRSS2, binds the novel coronavirus SARS-CoV-2 and facilitates its cellular entry. TheACE2gene is expressed in SARS-CoV-2 target cells, including Type II Pneumocytes (Ziegler, 2020), and is activated by interferons. Viral RNA was also detected in breast milk (Wu et al., 2020), raising the possibility thatACE2expression is under the control of cytokines through the JAK-STAT pathway. Here we show thatAce2expression in mammary tissue is induced during pregnancy and lactation, which coincides with the establishment of a candidate enhancer. The prolactin-activated transcription factor STAT5 binds to tandem sites that coincide with activating histone enhancer marks and additional transcription components. The presence of pan JAK-STAT components in mammary alveolar cells and in Type II Pneumocytes combined with the autoregulation of both STAT1 and STAT5 suggests a prominent role of cytokine signaling pathways in cells targeted by SARS-CoV-2.
An Optimal Lysis Time Maximizes Bacteriophage Fitness in Quasi-continuous Culture
Authors: Kannoly Sherin , Singh Abhyudai , Dennehy John J. 
Published: May 2020

ABSTRACTOptimality models have a checkered history in evolutionary biology. While optimality models have been successful in providing valuable insight into the evolution of a wide variety of biological traits, a common objection is that optimality models are overly simplistic and ignore organismal genetics. We revisit evolutionary optimization in the context of a major bacteriophage life history trait, lysis time. Lysis time refers to the period spanning phage infection of a host cell and its lysis, whereupon phage progeny are released. Lysis time, therefore, directly determines phage fecundity assuming progeny assembly rate is maximized. Noting that previous tests of lysis time optimality rely on batch culture, we implemented a quasi-continuous culture system to observe productivity of a panel of isogenic phage λ mutants differing in lysis time. We report that λ phage productivity in our experiments is maximized around an optimal lysis time of 63 min, which is the lysis time of the λ “wildtype” strain. We discuss this finding in light of recent results that lysis time variation is also minimized in the λ “wildtype” strain.
High dimensional single-cell analysis reveals iNKT cell developmental trajectories and effector fate decision
Authors: Baranek Thomas , Lebrigand Kevin , de Amat Herbozo Carolina , Gonzalez Loïc , Bogard Gemma , Dietrich Céline , Magnone Virginie , Boisseau Chloé , Jouan Youenn , Trottein François , Si-Tahar Mustapha , Leite-de-Moraes Maria , Mallevaey Thierry , Paget Christophe 
Published: May 2020

SummaryCD1d-restricted invariant Natural Killer T (iNKT) cells represent a unique class of T lymphocytes endowed with potent regulatory and effector immune functions. Although these functions are acquired during thymic ontogeny, the sequence of events that give rise to discrete effector subsets remains unclear. Using an unbiased single-cell transcriptomic analysis combined with functional assays, we revealed an unappreciated diversity among thymic iNKT cells, especially among iNKT1 cells. Mathematical modelling and biological methods unravelled a developmental map whereby iNKT2 cells constitute a transient branching point towards the generation of iNKT1 and iNKT17 cells, which reconciles the two previously proposed models. In addition, we identified the transcription co-factor Four-and-a-half LIM domains protein 2 (FHL2) as a critical cell-intrinsic regulator of iNKT1 specification. Thus, these data illustrate the changing transcriptional network that guides iNKT cell effector fate.
Seascape genomics reveals candidate molecular targets of heat stress adaptation in three coral species
Authors: Selmoni Oliver , Lecellier Gaël , Magalon Hélène , Vigliola Laurent , Benzoni Francesca , Peignon Christophe , Joost Stéphane , Berteaux-Lecellier Véronique 
Published: May 2020

AbstractAnomalous heat waves are causing a major decline of hard corals around the world and threatening the persistence of coral reefs. There are, however, reefs that had been exposed to recurrent thermal stress over the years and whose corals appeared tolerant against heat. One of the mechanisms that could explain this phenomenon is local adaptation, but the underlying molecular mechanisms are poorly known.In this work, we applied a seascape genomics approach to study heat stress adaptation in three coral species of New Caledonia (southwestern Pacific) and to uncover molecular actors potentially involved. We used remote sensing data to characterize the environmental trends across the reef system, and sampled corals living at the most contrasted sites. These samples underwent next generation sequencing to reveal single-nucleotide-polymorphisms (SNPs) of which frequencies associated with heat stress gradients. As these SNPs might underpin an adaptive role, we characterized the functional roles of the genes located in their genomic neighborhood.In each of the studied species, we found heat stress associated SNPs notably located in proximity of genes coding for well-established actors of the cellular responses against heat. Among these, we can mention proteins involved in DNA damage-repair, protein folding, oxidative stress homeostasis, inflammatory and apoptotic pathways. In some cases, the same putative molecular targets of heat stress adaptation recurred among species.Together, these results underscore the relevance and the power of the seascape genomics approach for the discovery of adaptive traits that could allow corals to persist across wider thermal ranges.
Systematic comparisons of customer base prediction accuracy: Pareto/NBD versus neural network
Authors: Xie Shao-Ming , Huang Chun-Yao 
Published: May 2020

PurposePredicting the inactivity and the repeat transaction frequency of a firm's customer base is critical for customer relationship management. The literature offers two main approaches to such predictions: stochastic modeling efforts represented by Pareto/NBD and machine learning represented by neural network analysis. As these two approaches have been developed and applied in parallel, this study systematically compares the two approaches in their prediction accuracy and defines the relatively appropriate implementation scenarios of each model.Design/methodology/approachBy designing a rolling exploration scheme with moving calibration/holdout combinations of customer data, this research explores the two approaches' relative performance by first utilizing three real world datasets and then a wide range of simulated datasets.FindingsThe empirical result indicates that neither approach is dominant and identifies patterns of relative applicability between the two. Such patterns are consistent across the empirical and the simulated datasets.Originality/valueThis study contributes to the literature by bridging two previously parallel analytical approaches applicable to customer base predictions. No prior research has rendered a comprehensive comparison on the two approaches' relative performance in customer base predictions as this study has done. The patterns identified in the two approaches' relative prediction performance provide practitioners with a clear-cut menu upon selecting approaches for customer base predictions. The findings further urge marketing scientists to reevaluate prior modeling efforts during the past half century by assessing what can be replaced by black boxes such as NNA and what cannot.
Determinants of competitiveness of the Czech SMEs: findings from the global competitiveness project
Authors: Dvouletý Ondřej , Blažková Ivana 
Published: May 2020

PurposeThe purpose of this paper is to examine the firm-level drivers of competitiveness of the Czech small- and medium-sized enterprises (SMEs) using the complex firm-level competitiveness index. The authors explored the relationship between firm competitiveness and firm characteristics such as size, age, industry affiliation and location.Design/methodology/approachThe complex competitiveness index as a proxy for firm competitiveness was calculated from the survey data. In total, 132 complete questionnaires filled in by representatives of randomly selected Czech SMEs were collected in 2018. Additional firm characteristics (size, age, industry affiliation and location) considered as determinants of competitiveness were obtained from the commercial database Albertina and from the Czech Statistical Office. The determinants of competitiveness were tested econometrically by estimation of multivariate regression models.FindingsThe authors mainly found a significant relationship between the firm size and competitiveness of the Czech SMEs. The authors have also confirmed that the least competitive enterprises are those operating in the agricultural sector and that regional location plays an important role in the determination of firm competitiveness.Practical implicationsThe identification of competitiveness drivers can provide entrepreneurs, managers and policymakers with important implications. It seems beneficial for the Czech SMEs to expand the scope of operations to achieve a larger company size, for example, by focussing on investment activities, direct marketing, improving entrepreneurial skills or by applying an aggressive sales strategy, especially towards markets with lower competition. Politicians may respond to these efforts by setting the appropriate policies that promote SMEs’ competitiveness, for example, through the hard and soft public support for financial and human resources.Originality/valueAlthough many studies on competitiveness have been published, there is still a limited number of firm-level studies looking at competitiveness from multiple angles rather than from the study of profitability and productivity. In contrast, the study uses a complex firm-level competitiveness index based on ten competitiveness pillars (technology, human capital, products, domestic market, networks, international markets, online presence, marketing, decision making and strategy) to capture the contribution of different resources and capabilities to firm competitiveness.
Exploring key variables of port competitiveness: evidence from Indonesian ports
Authors: Wahyuni Sari , Taufik Alif Azadi , Hui Felix Kin Peng 
Published: May 2020

Purpose
This study aims to understand the factors and problems that relate to Indonesian port competitiveness and the problems that need to be addressed by major actors such as the government and port corporations.

Design/methodology/approach
It combines quantitative analysis from 59 survey respondents and qualitative analysis from focus-group discussions and in-depth interviews with port experts, financial bodies, port corporations and government officials on the condition of Indonesian port planning, development and financing.

Findings
An Indonesian port competitiveness model was developed, comprising government support, business support and operational performance. The authors found a gap between policy expectation and realization of port facilitation, caused by inefficient government bureaucracy, customs clearance and strategic decision-making. The government's consistency and commitment need work to encourage investor interest. Road connectivity, intermodal transportation, and energy infrastructure should be enhanced to increase operational performance. These problems are caused by a lack of feasibility analysis, consideration of local economic developments, and late adoption of standard technology. The maritime-sector workforce should be trained to be more professional with foreign players, more innovative and more open towards foreign assistance.

Practical implications
Port competitiveness includes government-related variables. The government’s initiatives are welcomed but are not enough. Adequate attention to both micro and macro port is necessary to increase port competitiveness. Future research should develop more comprehensive solutions to increase port competitiveness in Indonesia using problems and factors outlined here.

Originality/value
The study investigated the unique factors and problems that relate to Indonesian port competitiveness. It uses a national scope and rich expert data involved in Indonesia's port industry.
The efficiency of GCC banks: the role of intellectual capital
Authors: Buallay Amina , Hamdan Allam Mohammed , Reyad Sameh , Badawi Sherine , Madbouly Araby 
Published: May 2020

Purpose
This study aims to examine the impact of intellectual capital (IC) efficiency on bank’s operational, financial and market performance.

Design/methodology/approach
The study examined 59 banks for 5 years to ends up with 295 observations. The independent variable is the modified value added IC component; the dependent variables are performance indicators (return on assets [ROA], return on equity [ROE] and Tobin’s Q [TQ]).

Findings
The findings deduced from the empirical results demonstrate that there is a positive relationship between intellectual capital efficiency and financial performance (ROE) and market performance (TQ).

Originality/value
The results of this study may give a wake-up call for banks to examine the reasons of imperfect relationship between the IC and asset efficiency (ROA).
A disability disclosure simulation as an educational tool
Authors: Lindsay Sally , Rezai Mana , Shen Winny , Lyons Brent 
Published: May 2020

PurposeMany employers struggle with how to have a disability disclosure discussion with their employees and job candidates. The primary purpose of this study was to identify issues relevant to disability disclosure discussions. In addition, we explored how simulations, as an educational tool, may help employers and managers.Design/methodology/approachSeven participants (four employers and three human resource professionals) took part in this study. We used a qualitative design that involved two focus group discussions to understand participants' experiences of building a simulation training scenario that focused on how to have a disability disclosure discussion. The simulation sessions were audio-recorded and analyzed using an open-coding thematic approach.FindingsFour main themes emerged from our analysis. Three themes focused on issues that participants identified as relevant to the disability disclosure process, including: (1) creating a comfortable and safe space for employees to disclose, (2) how to ask employees or job candidates about disability and (3) how to respond to employees disability disclosure. A fourth theme focused on how simulations could be relevant as an educational tool.Originality/valueDeveloping a simulation on disability disclosure discussions is a novel approach to educating employers and managers that has the potential to help enhance diversity and inclusion in the workplace. Further, the process that we followed can be used as a model for other researchers seeking to develop educational training scenarios on sensitive diversity and inclusion topics.
Institutional poverty as one of the main threats to the digital economy
Authors: Skiter Natalia N. , Ketko Nataliya V. , Rogachev Aleksey F. , Gushchina Elena G. , Vitalyeva Elena M. 
Published: May 2020

PurposeThe article considers the causes of such a fundamental problem like poverty.Design/methodology/approachThe authors analyzed the interdependence of poverty and the development of the digital economy, and also examined possible ways to develop measures to reduce the spread of poverty.FindingsAn algorithm is proposed for diagnosing the level of poverty development, and a mechanism has been developed to reduce it due to the development of self-employment of the population.Originality/valueThe main scientific task to be solved by the study is to improve the quality of life of the population of the regions of Russia by reducing poverty and increasing employment in the form of self-employment.