bluuebunny/crossref_metadata_2025_split huggingface dataset:
Parasites as niche modifiers for the microbiome: A field test with multiple parasites
Authors: O’Keeffe Kayleigh R. , Halliday Fletcher W. , Jones Corbin D. , Carbone Ignazio , Mitchell Charles E. 
Published: April 2020

AbstractParasites can affect and be affected by the host’s microbiome, with consequences for host susceptibility, parasite transmission, and host and parasite fitness. Yet, there are two aspects of the relationship between parasite infection and the host microbiome that remain little understood: the nature of the relationship under field conditions, and how the relationship varies among parasite species. To overcome these limitations, we assayed the within-leaf fungal community in a grass population to investigate how diversity and composition of the fungal microbiome are associated with natural infection by fungal parasites with different feeding strategies. We hypothesized that parasites that more strongly modify niches available within a host will thereby alter the microbial taxa that can colonize the community and be associated with greater changes in microbiome diversity and composition. A parasite that creates necrotic tissue to extract resources (necrotrophs) may act as a particularly strong niche modifier whereas one that does not (biotrophs) may not. Barcoded amplicon sequencing of the fungal ITS region revealed that the microbiome of leaf segments that were symptomatic of necrotrophs had lower fungal diversity and distinct composition compared to segments that were asymptomatic or symptomatic of other parasites. There were no clear differences in fungal diversity or composition between leaf segments that were asymptomatic and segments that were symptomatic of other parasite feeding strategies. This supports the hypothesis that within-host niches link infection by parasites to the host’s microbiome. Together, these results highlight the importance of parasite traits in determining parasite impacts on the host’s microbiome.
Schrödinger’s phenotypes: herbarium specimens show two-dimensional images are both good and (not so) bad sources of morphological data
Authors: Borges Leonardo M. , Reis Victor Candido , Izbicki Rafael 
Published: April 2020

AbstractMuseum specimens are the main source of information on organisms’ morphological features. Although access to this information was commonly limited to researchers able to visit collections, it is now becoming freely available thanks to the digitization of museum specimens. With these images, we will be able to collectively build large-scale morphological datasets, but these will only be useful if the limits to this approach are well-known. To establish these limits, we used two-dimensional images of plant specimens to test the precision and accuracy of image-based data and analyses.To test measurement precision and accuracy, we compared leaf measurements taken from specimens and images of the same specimens. Then we used legacy morphometric datasets to establish differences in the quality of datasets and multivariate analyses between specimens and images. To do so, we compared the multivariate space based on original legacy data to spaces built with datasets simulating image-based data.We found that trait measurements made from images are as precise as those obtained directly from specimens, but as traits diminish in size, the accuracy drops as well. This decrease in accuracy, however, has a very low impact on dataset and analysis quality. The main problem with image-based datasets comes from missing observations due to image resolution or organ overlapping. Missing data lowers the accuracy of datasets and multivariate analyses. Although the effect is not strong, this decrease in accuracy suggests caution is needed when designing morphological research that will rely on digitized specimens.As highlighted by images of plant specimens, 2D images are reliable measurement sources, even though resolution issues lower accuracy for small traits. At the same time, the impossibility of observing particular traits affects the quality of image-based datasets and, thus, of derived analyses. Despite these issues, gathering phenotypic data from two-dimensional images is valid and may support large-scale studies on the morphology and evolution of a wide diversity of organisms.
SLX4IP-mediated telomere maintenance is essential for androgen receptor-independent castration-resistant prostate cancer
Authors: Mangosh Tawna L. , Awadallah Wisam N. , Grabowska Magdalena M. , Taylor Derek J. 
Published: April 2020

ABSTRACTIn advanced prostate cancer, resistance to androgen deprivation therapy is achieved through numerous mechanisms, including loss of the androgen receptor (AR) allowing for AR-independent growth. Therapeutic options are limited for AR-independent castration-resistant prostate cancer, and defining mechanisms critical for its survival is of utmost importance for targeting this lethal disease. Our studies have focused on defining the telomere maintenance mechanism (TMM) required for castration-resistant prostate cancer (CRPC) cell survival. TMMs are responsible for telomere elongation to instill replicative immortality and prevent senescence, with the two TMM pathways available being telomerase and alternative lengthening of telomeres (ALT). Here, we show that AR-independent CRPC exhibits ALT hallmarks and limited telomerase expression and activity, whereas AR-dependent models use telomerase for telomere maintenance. AR-independent CRPC exhibited elevated levels of SLX4IP, a protein implicated in TMM switching. SLX4IP overexpression in AR-dependent CRPC C4-2B cells promoted ALT hallmarksin vitro. SLX4IP knockdown in AR-independent CRPC cells (DU145 and PC-3) led to the loss of ALT hallmarks, dramatic telomere shortening, induction of senescence, and reduced tumor volume. Using anin vitromodel of CRPC progression, induction of neuroendocrine differentiation in AR-dependent CRPC cells promoted ALT hallmarks in an SLX4IP-dependent manner. Lack of sufficient SLX4IP expression prevented ALT hallmarks rendering a TMM deficient environment, thus inducing senescence. This study demonstrates a unique reliance of AR-independent CRPC on SLX4IP-mediated ALT. Furthermore, ALT hallmark inhibition via SLX4IP induces senescence, thereby abolishing the replicative immortality of AR-independent CRPC.
Exchange of a single amino acid residue in the cryptophyte phycobiliprotein lyaseGtCPES expands its substrate specificity
Authors: Tomazic Natascha , Overkamp Kristina E. , Aras Marco , Pierik Antonio J. , Hofmann Eckhard , Frankenberg-Dinkel Nicole 
Published: April 2020

ABSTRACTCryptophyte algae are among the few eukaryotes that employ phycobiliproteins (PBP) for light harvesting during oxygenic photosynthesis. In contrast to the cyanobacterial PBP that are organized in large membrane-associated super complexes, the phycobilisomes, those from cryptophytes are soluble within the chloroplast thylakoid lumen. Their light-harvesting capacity is due to covalent linkage of several open-chain tetrapyrrole chromophores (phycobilins).Guillardia thetautilizes the PBP phycoerythrin PE545 with 15,16-dihydrobiliverdin (DHBV) in addition to phycoerythrobilin (PEB) as chromophores. Thus far, the assembly of cryptophyte PBPs is not yet completely understood but involves the action of PBP-lyases as shown for cyanobacterial PBP. PBP-lyases facilitate the attachment of the chromophore in the right configuration and stereochemistry. Here we present the functional characterization of eukaryotic S-type PBP lyaseGtCPES fromG. theta. We showGtCPES mediated transfer and covalent attachment of PEB to the conserved Cys82of the acceptor PBP β-subunit (PmCpeB) ofProchlorococcus marinusMED4. Based on the previously solved crystal structure, theGtCPES binding pocket was investigated using site-directed mutagenesis. Thereby, amino acid residues involved in phycobilin binding and transfer were identified. Interestingly, exchange of a single amino acid residue Met67to Ala extended the substrate specificity to phycocyanobilin (PCB) likely by enlarging the substrate-binding pocket. VariantGtCPES_M67A binds both PEB and PCB forming a stable, colorful complexin vitroandin vivoproduced inEscherichia coli.GtCPES_M67A is able to mediate PCB transfer to Cys82ofPmCpeB. Based on our data we postulate that a single amino acid residue determines the bilin-specificity of phycoerythrin S-type lyases but that additional factors regulate hand over to the target protein.
Variation at the common polysaccharide antigen locus drives lipopolysaccharide diversity within theP. syringaespecies complex
Authors: Jayaraman Jay , Jones William T. , Harvey Dawn , Hemara Lauren M. , McCann Honour C. , Yoon Minsoo , Warring Suzanne L. , Fineran Peter C. , Mesarich Carl H. , Templeton Matthew D. 
Published: April 2020

ABSTRACTThe common polysaccharide antigen (CPA) from the lipopolysaccharide (LPS) component of cell walls from the species complexPseudomonas syringaeis highly variable both in structure and immunological specificity, but the genetic basis for this is not well understood. We have characterised the CPA locus fromP. syringaepv.actinidiae(Psa). This locus has a modular structure with genes for both L- and D- rhamnose (Rha) biosynthesis and that of an unknown sugar. It also contains an operon coding for ABC transporter subunits, a bifunctional glycosyltransferase and an O-methyltransferase. This operon is predicted to have a role intransport,elongation andtermination of the Rha backbone of the CPA oligosaccharide and is referred to as the TET operon. This is the first report of the identification of this operon inP. syringae. Two alleles of the TET operon were present amongst the different biovars ofPsaand lineages of the closely related pathovarP. syringaepv.actinidifoliorum. This allelic variation was reflected in the electrophoretic properties of purified LPS from the different isolates. Gene knockout of the TET operon allele from biovar 1 and replacement with that from biovar 3, demonstrated the link between the genetic locus and the electrophoretic and immunogenic properties of the LPS molecules inPsa. Sequence analysis of the TET operon from a wide range ofP. syringaeandP. viridiflavaisolates displayed a phylogenetic history which is incongruent with core gene phylogeny, but correlates with previously reported tailocin sensitivity, suggesting a functional relationship between LPS structure and tailocin susceptibility.
HbtR, a heterofunctional homolog of the virulence regulator TcpP, facilitates the transition between symbiotic and planktonic lifestyles inVibrio fischeri
Authors: Bennett Brittany D. , Essock-Burns Tara , Ruby Edward G. 
Published: April 2020

AbstractThe bioluminescent bacteriumVibrio fischeriforms a mutually beneficial symbiosis with the Hawaiian bobtail squid,Euprymna scolopes, in which the bacteria, housed inside a specialized light organ, produce light used by the squid in its nocturnal activities. Upon hatching,E. scolopesjuveniles acquireV. fischerifrom the seawater through a complex process that requires, among other factors, chemotaxis by the bacteria along a gradient ofN-acetylated sugars into the crypts of the light organ, the niche in which the bacteria reside. Once inside the light organ,V. fischeritransitions into a symbiotic, sessile state in which the quorum-signaling regulator LitR induces luminescence. In this work we show that expression oflitRand luminescence are repressed by a homolog of theV. choleraevirulence factor TcpP, which we have named HbtR. Further, we demonstrate that LitR represses genes involved in motility and chemotaxis into the light organ and activates genes required for exopolysaccharide production.ImportanceTcpP homologs are widespread throughout theVibriogenus; however, the only protein in this family described thus far is aV. choleraevirulence regulator. Here we show that HbtR, the TcpP homolog inV. fischeri, has both a biological role and regulatory pathway completely unlike that inV. cholerae. Through its repression of the quorum-signaling regulator LitR, HbtR affects the expression of genes important for colonization of theE. scolopeslight organ. While LitR becomes activated within the crypts, and upregulates luminescence and exopolysaccharide genes and downregulates chemotaxis and motility genes, it appears that HbtR, upon expulsion ofV. fischericells into seawater, reverses this process to aid the switch from a symbiotic to a planktonic state. The possible importance of HbtR to the survival ofV. fischerioutside of its animal host may have broader implications for the ways in which bacteria transition between often vastly different environmental niches.
Selective Cell Propagation via Micropatterning of Thermal-activated Hydrogel
Authors: Chiu Jeffrey C.Y. , Teodoro Joyce A. , Lee Jeong Hyun , Matthews Kerryn , Duffy Simon P. , Ma Hongshen 
Published: April 2020

AbstractThe ability to selectively propagate specific cells is fundamentally important to the development of clonal cell populations. Current methods rely on techniques such as limiting dilution, colony picking, and flow cytometry to transfer single cells into single wells, resulting in workflows that are low-throughput, slowed by propagation kinetics, and susceptible to contamination. Here, we developed a method, called selective laser gelation (SLG), to micropattern hydrogels in cell culture media in order to encapsulate specific cells to selectively arrest their growth. This process relies on the inverse gelation of methylcellulose, which forms a hydrogel when heated rather than cooled. Local heating using an infrared laser enables hydrogel micropatterning, while phase transition hysteresis retains the hydrogel after laser excitation. As a demonstration, we used this approach to selectively propagate transgenic CHO cells with increased antibody productivity. More generally, hydrogel micropatterning provides a simple and non-contact method to selective propagation of cells based on features identified by imaging.One Sentence SummaryInverse gelation of methylcellulose enables hydrogel micropatterning to selectively propagate cells identified by microscopy.
Optimally scheduling and loading tow trains of in-plant milk-run delivery for mixed-model assembly lines
Authors: Zhou Binghai , Zhu Zhexin 
Published: April 2020

Purpose
This paper aims to investigate the scheduling and loading problems of tow trains for mixed-model assembly lines (MMALs). An in-plant milk-run delivery model has been formulated to minimize total line-side inventory for all stations over the planning horizon by specifying the departure time, parts quantity of each delivery and the destination station.

Design/methodology/approach
An immune clonal selection algorithm (ICSA) combined with neighborhood search (NS) and simulated annealing (SA) operators, which is called the NSICSA algorithm, is developed, possessing the global search ability of ICSA, the ability of SA for escaping local optimum and the deep search ability of NS to get better solutions.

Findings
The modifications have overcome the deficiency of insufficient local search and deepened the search depth of the original metaheuristic. Meanwhile, good approximate solutions are obtained in small-, medium- and large-scale instances. Furthermore, inventory peaks are in control according to computational results, proving the effectiveness of the mathematical model.

Research limitations/implications
This study works out only if there is no breakdown of tow trains. The current work contributes to the in-plant milk-run delivery scheduling for MMALs, and it can be modified to deal with similar part feeding problems.

Originality/value
The capacity limit of line-side inventory for workstations as well as no stock-outs rules are taken into account, and the scheduling and loading problems are solved satisfactorily for the part distribution of MMALs.
Determinants and outcome of Islamic corporate social responsibility (ICSR) adoption in Islamic banking industry of Pakistan
Authors: Bukhari Syed Asim Ali , Hashim Fathyah , Amran Azlan Bin 
Published: April 2020

PurposeThe purpose of this study is to empirically examine the determinants and outcomes of Islamic corporate social responsibility (ICSR) adoption in Islamic bank branches in Pakistan. The research framework examines the influence of stakeholder’s pressure on ICSR adoption. It also analyses the relationship between ICSR adoption and intangible outcomes achieved by the Islamic bank branch.Design/methodology/approachA total of 400 questionnaires were distributed through a mail survey to Islamic bank branches in Pakistan. The respondents of the study were the branch manager of Islamic bank branches in Pakistan. A simple random sampling technique was used and resulted in the collection of 293 usable questionnaires. SMART PLS was used to statistically analyse the data using partial least squares structural equation modelling approach. The measurement and structural models were analysed.FindingsThe results indicate a significant and positive relationship between Shariah supervisory board pressure, competitor pressure and ICSR adoption in Islamic bank branches. A moderate strength positive relationship was found out between top management pressure and ICSR adoption. Results reveal that customer pressure and community pressure have an insignificant influence on ICSR adoption. Data analysis shows that the adoption of ICSR practices have a significant and positive influence on an Islamic bank branch’s Intangible outcomes.Research limitations/implicationsThe sample size was relatively small because of the limited time duration.Originality/valueThe construct of ICSR has not been extensively researched upon especially through empirical studies. Limited research exists in the area of factors than can influence Islamic bank branches to adopt ICSR practices and currently no empirical research has focussed on the intangible outcomes that can be achieved through ICSR adoption by an Islamic bank branch. The limited study exists in the Pakistan context as well, which is a rapidly growing Islamic banking industry.
The contribution of physical retail to value co-creation in the town centre ecosystem; evidence from Grimsey
Authors: Cassidy Kim Julie , Grimsey William , Blackley Nelson 
Published: April 2020

PurposeThe purpose of this paper is to identify ways to reconfigure physical retailing to ensure it maintains a sustainable position within the town centre ecosystem in the twenty-first century. The discussion draws on the evolving service-dominant logic (S-DL) and its service ecosystems perspective and evidence of best practice provided by actors involved in town centre regeneration between 2013 and 2018.Design/methodology/approachThe research adopts a case methodology drawing on data submitted and analysed as part of the Grimsey Review 2, an independent review of the UK town centres. The data set provides examples of good practice sourced from industry leaders, trade bodies, local authorities and extensive social media engagement.FindingsThe paper evaluates the response of physical retail through an S-DL and service ecosystem lens. The review of best practice suggests that physical retailers have the best chance of survival if they proactively collaborate with other actors within a wider community hub solution, align their strategic position and operations to a holistic centre place plan and take steps to actively engage operant resources of consumers in creating physical store experiences.Practical implicationsThe paper provides an evaluation of best practice in town centre regeneration implemented between 2013 and 2018. The case offers a rich bank of examples, illustrating how physical retailers are responding to the twenty-first-century challenges facing town centres. It makes recommendations for further improvement in the three critical areas identified above.Originality/valueThis paper provides further empirical support for the application of an S-DL and service ecosystem perspective to place marketing. To achieve effective value co-creation, physical retailers need to align themselves more closely with other actors in the system and maximise the potential of operant (and operand) consumer resources.
Narcissism personality trait and performance: task-oriented leadership and authoritarian styles as mediators
Authors: Sakkar Sudha Kiran , Shahnawaz M. Ghazi 
Published: April 2020

PurposeThe present study explored the direct as well as indirect relationships between narcissism personality trait and performance. Two leadership styles (task oriented and authoritarian styles) were identified as possible mediators.Design/methodology/approachNarcissism was measured by using Narcissistic Personality Inventory (Ameset al., 2006), performance was measured by performance scale (Greene-Shortridge, 2008). Sinha's leadership scale (Sinha, 2008) was used to measure task-oriented and authoritarian leadership styles. 273 senior-level managers of a big public sector Indian organization participated in the study. SPSS 22 and SmartPLS 2.0 were used to analyze the data.FindingsCorrelation result shows that narcissism personality trait was positively related to authoritarian leadership style and negatively to task-oriented leadership style, task performance and teamwork dimensions of performance. Task-oriented leadership style mediated the relationship between narcissism and task performance and teamwork more than the authoritarian leadership style.Originality/valueThe study attempts to empirically test the behavioral manifestation of narcissism personality trait as positive or negative and has considered the whole measure of performance which has not been previously explored. Practical implications were also highlighted beside the theoretical concerns.
The relationship between abusive supervision and employee's reaction: the job demands-resources model perspective
Authors: Huang Liang-Chih , Lin Cheng-Chen , Lu Szu-Chi 
Published: April 2020

PurposeBased on the job demands-resources model, the present study proposes viewing abusive supervision as one type of job demand causing employees' emotional exhaustion, which results in psychological withdrawal behavior. In addition, job crafting can be viewed as a means to acquire job resources, and it buffers the influence of abusive supervision on employees' emotional exhaustion. Moreover, the present study also proposes the moderating effect of job crafting on abusive supervision and psychological withdrawal behavior will be mediated by emotional exhaustion.Design/methodology/approachConsidering the issue of common method variance, data were not only collected in a multi-temporal research design but also tested by Harman's one-factor test. In addition, a series of confirmatory factor analyses was conducted to ensure the discriminant validity of measures. The moderated mediation hypotheses were tested on a sample of 267 participants.FindingsThe process model analysis showed that emotional exhaustion partially mediates the relationship between abusive supervision and psychological withdrawal behavior. Moreover, job crafting buffers the detrimental effect of abusive supervision on emotional exhaustion, and the less exhausted employees exhibit less psychological withdrawal behavior than those exhausted.Originality/valueThis study proposed a moderated mediation model to examine how and when abusive supervision leads to more employees' psychological withdrawal behaviors, and found that emotional exhaustion is one potential mechanism and job crafting is one potential moderator. Specifically, it was revealed that employees view abusive supervision as a kind of social and organizational aspect of job demands which will exacerbate emotional exhaustion, and, in turn, lead to more psychological withdrawal behavior. However, when employees view themselves as job crafter, they can adopt various job crafting behaviors to decrease the emotional exhaustion, and thus less psychological withdrawal behavior.