bluuebunny/crossref_metadata_2025 huggingface dataset:
Is Mycetoma a Vector-Borne Disease: The First Report on the Detection of Madurella mycetomatis in Ticks
Authors: Azrag RS , Bakhiet SM , Almalik AM , Mohamed AH , Fahal AH
Published: September 2019

Currently, there is a massive gap the mycetoma knowledge in particular in its epidemiological characteristics, the infection route, the predisposing factors and the host susceptibility. With this background, the present cross-sectional descriptive entomological study was conducted to determine the possible role of arthropod vectors in the transmission of eumycetoma as well as the knowledge, attitude and practice (KAP) among the villagers towards that in a mycetoma endemic village at Sennar State, Sudan.

The study showed an abundance of indoors and outdoors arthropod vectors, and that included ticks, mosquitoes, sandflies, cockroaches and houseflies in the studied area. Ticks were more frequent, and they belonged to three genera and four species, and the later included Hyalomma (H.) anatolicum (11.03%), Hyalomma (H.) rufipes (0.67%), Rhipicephalus (R.) everts (73.1%) and Amblyoma (A.) lepidium (15.2%). The different types of the collected arthropod vectors were pooled in groups, and each group was screened for the presence of the Madurella (M.) mycetomatis DNA, the most frequent causative agents of eumycetoma in the studied area. The DNA was extracted, and amplification of the genomic rRNA genes was done by using universal pan fungal primers and specific M. mycetomatis primers. One pool containing R. evertsi DNA samples and one sample of H. Rufipes DNA gave positive results following PCR amplification of the universal fungal positive primers while H. rufipes sample gave positive results for M. mycetomatis using a specific primer. An association between the animals’ dungs, ticks and mycetoma transmission can be suggested from this study. However, further in-depth studies are needed to verify that.

Author summary

Mycetoma is a severely neglected tropical disease characterised by painless subcutaneous tumour-like swellings frequently noted in the extremities. There is a massive knowledge gap in transmission, infection route, and historically, it is believed to be associated with minor trauma caused by thorn pricks. This study was designed to determine the possible role of arthropods in mycetoma transmission in an endemic area in Sudan during the cold dry season. Pools of medically important arthropods were screened for mycetoma causative agents using DNA based method. The villagers’ habits and knowledge on arthropod vectors were examined using a pre-designed questionnaire. The results showed various presences of many arthropod vectors. Ticks were found in high prevalence, and densities in domestic animals found inside houses and the villagers had high contact level with the ticks in comparison to other vectors. The study reports for the first time, the detection of the causative agents of mycetoma in a pool of ticks. More studies on the possible role of ticks in the transmission of mycetoma diseases are badly needed to delineate the possible role of ticks on transmission of mycetoma.
Mechano-responsiveness of fibrillar adhesions on stiffness-gradient gels
Authors: Barber-Pérez Nuria , Georgiadou Maria , Guzmán Camilo , Isomursu Aleksi , Hamidi Hellyeh , Ivaska Johanna
Published: September 2019

Fibrillar adhesions are important structural and adhesive components in fibroblasts that are critical for fibronectin fibrillogenesis. While nascent and focal adhesions are known to respond to mechanical cues, the mechanoresponsive nature of fibrillar adhesions remains unclear. Here, we used ratiometric analysis of paired adhesion components to determine an appropriate fibrillar adhesion marker. We found that active α5β1-integrin exhibits the most definitive fibrillar adhesion localisation compared to other proteins, such as tensin-1, reported to be in fibrillar adhesions. To elucidate the mechanoresponsiveness of fibrillar adhesions, we designed and fabricated thin polyacrylamide (PA) hydrogels, embedded with fluorescently labelled beads, with physiologically relevant stiffness gradients using a cost-effective and reproducible technique. We generated a correlation curve between bead density and hydrogel stiffness, thus allowing the use of bead density as a readout of stiffness, eliminating the need for specialised knowhow including atomic force microscopy (AFM). We find that stiffness promotes the growth of fibrillar adhesions in a tensin-dependent manner. Thus, the formation of these extracellular matrix-depositing structures is coupled to the mechanical parameters of the cell environment and may enable cells to fine-tune their matrix environment in response to alternating physical conditions.
Dynamic analysis of pulsed cisplatin identifies effectors of resistance in lung adenocarcinoma
Authors: Hastings Jordan F. , Gonzalez-Rajal Alvaro , Han Jeremy Z.R. , McCloy Rachael A. , O’Donnell Yolande E.I. , Phimmachanh Monica , Murphy Alexander D. , Nagrial Adnan , Daneshvar Dariush , Chin Venessa , Watkins D. Neil , Burgess Andrew , Croucher David R.
Published: September 2019

Identification of clinically viable strategies for overcoming resistance to platinum chemotherapy in lung adenocarcinoma has been hampered by inappropriately tailoredin vitroassays of drug response. Therefore, using a pulse model that closely recapitulates thein vivopharmacokinetics of platinum therapy, we profiled cisplatin-induced signalling, DNA damage and apoptotic responses across a panel of lung adenocarcinoma cell lines. By coupling this data with real-time, single cell imaging of cell cycle and apoptosis, we show thatTP53mutation status influenced the mode of cisplatin induced cell cycle arrest, but could not predict cisplatin sensitivity. In contrast, P70S6K-mediated signalling promoted resistance by increasing p53/p63 and p21 expression, reducing double-stranded DNA breaks and apoptosis. Targeting P70S6K sensitised bothTP53wildtype and null lines to cisplatin, but notTP53mutant lines. In summary, usingin vitroassays that mimicin vivopharmacokinetics identified P70S6K as a robust mediator of cisplatin resistance and highlighted the importance of considering somatic mutation status when designing patient-specific combination therapies.
DJ-1 (Park7) affects the gut microbiome, metabolites and development of Innate Lymphoid cells (ILCs)
Authors: Singh Yogesh , Trautwein Christoph , Dhariwal Achal , Salker Madhuri S , Alauddin Mohammed , Zigmare Laimdota , Pelzl Lisan , Feger Martina , Matthes Jakob , Casadei Nicolas , Föller Michael , Pachauri Vivek , Park David S , Mak Tak W , Frick Julia S , Wallwiener Diethelm , Brucker Sara Y , Lang Florian , Riess Olaf
Published: September 2019

The proper communication between gut and brain is pivotal for maintenance of health and dysregulation of the gut-brain axis can lead to several clinical disorders. Also, in Parkinson’s disease (PD) 85% of all patients experienced constipation long before showing any signs of motor phenotypes. For differential diagnosis and when it comes to preventive treatment there is an urgent need for the identification of biomarkers indicating early disease stages long before the disease phenotype manifests. DJ-1 is a chaperon protein involved in the protection against PD and genetic mutations in this protein have been shown to cause familial PD. However, how the deficiency of DJ-1 modifies the PD risk remains incompletely understood. In the present study we provide evidence that DJ-1 is implicated in shaping the gut microbiome including their metabolite production or innate immune cells (ILCs) development. We revealed that in 4 months old mice genetic deficiency of DJ-1 leads to significantly decrease in several bacterial genera and significantly increase in two specific genera, namelyAlistipesandRikenella. DJ-1 deficient mice have a higher production of calprotectin/MCP-1 inflammatory protein - a known protein involved in colonic inflammation – and significantly higher expression of glial fibrillary acidic protein (GFAP) than control littermates. Expression of a-Synuclein, a key protein in Lewy bodies, in the colon was not significantly different between genotypes. Metabolic profiles of feces extracts analysed by H1-NMR spectroscopy showed increased short chain fatty acids (SCFAs) and decreased amino acid levels, suggesting a general switch from protein towards fibre degrading strains in DJ-1 deficient mice. We observed that Malonate - which is known to influence the immune system – has significantly higher concentrations in DJ-1 deficient mice. Moreover, DJ-1 deficient mice have high levels of the phenol derivate 3-(3-Hydroxyphenyl) propanoic acid (3-HPPA) which is a breakdown product of aromatic substrates like tyrosine, phenylalanine and polyphenols. DJ-1 deficient mice also showed significantly reduced percentage of ILCs. Thus, our data suggests that absence of DJ-1 leads to increase in gut inflammatory bacteria composition, deregulated metabolites and dysregulated innate immunity which could be a key factor in the initiation of PD disease in the gut, and potentially also in brain during disease progression.
OTULIN prevents liver inflammation and hepatocellular carcinoma by inhibiting FADD- and RIPK1 kinase-mediated hepatocyte apoptosis
Authors: Verboom Lien , Martens Arne , Priem Dario , Hoste Esther , Sze Mozes , Vikkula Hanna , Voet Sofie , Bongiovanni Laura , de Bruin Alain , Scott Charlotte L. , Pasparakis Manolis , Bertrand Mathieu JM , van Loo Geert
Published: September 2019

Inflammatory signaling pathways are tightly regulated to avoid chronic inflammation and the development of inflammatory pathologies. OTULIN is a deubiquitinating enzyme that specifically cleaves linear ubiquitin chains generated by the linear ubiquitin chain assembly complex (LUBAC), and OTULIN deficiency causes OTULIN-related autoinflammatory syndrome (ORAS) in humans. OTULIN was shown to negatively control NF-κB signaling in response to various stimuli, but also to protect cells from tumor necrosis factor (TNF)-induced apoptosis. To investigate the importance of OTULIN in liver homeostasis and pathology, we developed a novel mouse line specifically lacking OTULIN in liver parenchymal cells. These mice spontaneously develop a severe liver disease, characterized by liver inflammation, hepatocyte apoptosis and compensatory hepatocyte proliferation, leading to steatohepatitis, fibrosis and hepatocellular carcinoma (HCC). Genetic ablation of Fas-associated death domain (FADD) completely rescues the severe liver pathology, and knock-in expression of kinase inactive receptor-interacting protein kinase 1 (RIPK1) significantly protects from developing liver disease, demonstrating that death receptor-mediated apoptosis of OTULIN-deficient hepatocytes triggers disease pathogenesis in this model. Finally, we demonstrate that type I interferons contribute to disease pathogenesis in hepatocyte-specific OTULIN deficient mice. Together, our study reveals the critical importance of OTULIN in protecting hepatocytes from death, and thereby avoid development of chronic liver inflammation and HCC in mice.
Disrupted gene networks in subfertile hybrid house mice
Authors: Morgan Katy , Harr Bettina , White Michael A. , Payseur Bret A. , Turner Leslie M.
Published: September 2019

The Dobzhansky-Muller model provides a widely accepted mechanism for the evolution of reproductive isolation: incompatible substitutions disrupt interactions between genes. To date, few candidate incompatibility genes have been identified, leaving the genes driving speciation mostly uncharacterized. The importance of interactions in the Dobzhansky-Muller model suggests that gene coexpression networks provide a powerful framework to understand disrupted pathways associated with postzygotic isolation. Here, we perform Weighted Gene Coexpression Network Analysis (WGCNA) to infer gene interactions in hybrids of two recently diverged European house mouse subspecies, Mus mus domesticus and M. m. musculus, which commonly show hybrid male sterility or subfertility. We use genome-wide testis expression data from 467 hybrid mice from two mapping populations: F2s from a laboratory cross between wild-derived pure subspecies strains and offspring of natural hybrids captured in the Central Europe hybrid zone. This large data set enabled us to build a robust consensus network using hybrid males with fertile phenotypes. We identify several expression modules, or groups of coexpressed genes, that are disrupted in subfertile hybrids, including modules functionally enriched for spermatogenesis, cilium and sperm flagellum organization, chromosome organization and DNA repair, and including genes expressed in spermatogonia, spermatocytes and spermatids. Our network-based approach enabled us to hone in on specific hub genes likely to be influencing module-wide gene expression and hence potentially driving Dobzhansky-Muller incompatibilities. A total of 69 (24.6%) of these genes lie in sterility loci identified previously in these mapping populations, and represent promising candidate barrier genes and targets for future functional analysis.
Free fatty acid receptor 4 is a nutrient sensor that resolves inflammation to maintain cardiac homeostasis
Authors: Murphy Katherine A. , Harsch Brian A. , Healy Chastity L. , Joshi Sonal S. , Huang Shue , Walker Rachel E. , Wagner Brandon M. , Ernste Katherine M. , Huang Wei , Block Robert , Wright Casey D. , Tintle Nathan , Jensen Brian C. , Shearer Gregory C , O’Connell Timothy D.
Published: September 2019

Background

Non-­resolving activation of immune responses is central to the pathogenesis of heart failure (HF). Free fatty acid receptor 4 (Ffar4) is a G-protein coupled receptor (GPR) for medium-and long-chain fatty acids (FA) that regulates metabolism and attenuates inflammation in diabetes and obesity. Here, we tested the hypothesis that Ffar4 functions as a cardioprotective nutrient sensor that resolves inflammation to maintain cardiac homeostasis.

Methods

Mice with systemic deletion of Ffar4 (Ffar4KO) were subjected to pressure overload by transverse aortic constriction (TAC). Transcriptome analysis of cardiac myocytes was performed three days post-TAC. Additionally, Ffar4-mediated effects on inflammatory oxylipin production in cardiac myocytes and oxylipin composition in plasma lipoproteins were evaluated.

Results

In Ffar4KO mice, TAC induced more severe remodeling, identifying an entirely novel cardioprotective role for Ffar4 in the heart. Transcriptome analysis 3-days post-TAC indicated a failure to induce cell death and inflammatory genes in Ffar4KO cardiac myocytes, as well as a specific failure to induce cytoplasmic phospholipase A2α (cPLA2α) signaling genes. In cardiac myocytes, Ffar4 signaling through cPLA2α-cytochrome p450 ω/ω-1 hydroxylase induced production of the EPA-derived anti-inflammatory oxylipin 18-hydroxyeicosapentaenoic acid (18-HEPE). Systemically, loss of Ffar4 altered oxylipin content in circulating plasma lipoproteins consistent with a loss of anti-inflammatory oxylipins at baseline, and inability to produce both pro-inflammatory and pro-resolving oxylipins following TAC. Finally, we confirmed that Ffar4 is expressed in human heart and down-regulated in HF.

Conclusions

Our results identify a novel function for Ffar4 in the heart as a FA nutrient sensor that resolves inflammation to maintain cardiac homeostasis.
Altered Relationship between Soluble TREM2 and Inflammatory Markers in Young Adults with Down Syndrome
Authors: Weber Grace E. , Koenig Katherine , Khrestian Maria , Shao Yvonne , Tuason Elizabeth D. , Gramm Marie , Lal Dennis , Leverenz James B. , Bekris Lynn M.
Published: September 2019

Individuals with Down syndrome (DS) develop Alzheimer’s disease (AD) - related neuropathology, characterized by amyloid plaques with amyloid β (Aβ) and neurofibrillary tangles with tau accumulation more frequently and at an earlier age than their neurotypical counterparts. Peripheral inflammation and the innate immune response are elevated in DS. Triggering receptor expressed in myeloid cells 2 (TREM2) genetic variants are risk factors for AD and other neurodegenerative diseases. A soluble cleavage product of TREM2 (sTREM2) has been described as elevated in AD cerebrospinal fluid and positively correlates with Aβ and cognitive decline. There is relatively little information about TREM2 in DS. The objective of this study was to examine the relationship between sTREM2 and inflammatory markers in DS, prior to the development of dementia symptoms. Since TREM2 plays a role in the innate immune response and has been associated with dementia, the hypothesis of this exploratory study was that young adults with DS pre-dementia (n=15, mean age 29.5 years) would exhibit a different relationship between sTREM2 and inflammatory markers in plasma, compared to neurotypical, age-matched controls (n=16, mean age 29.6 years). Indeed, young adults with DS had significantly elevated plasma sTREM2 and inflammatory markers. In addition, in young adults with DS, sTREM2 correlated positively with 24 of the measured cytokines, while there were no significant correlations in the control group. Hierarchical clustering of sTREM2 and cytokine concentrations also differed between the group with DS and controls, supporting the hypothesis that its function is altered in people with DS pre-dementia. This exploratory study provides a basis for future studies investigating the relationship between TREM2 and the broader immune response pre-dementia.
A multivariate phylogenetic comparative method incorporating a flexible function between discrete and continuous traits
Authors: Haba Yuki , Kutsukake Nobuyuki
Published: September 2019

One major challenge of using the phylogenetic comparative method (PCM) is the analysis of the evolution of interrelated continuous and discrete traits in a single multivariate statistical framework. In addition, more intricate parameters such as branch-specific directional selection have rarely been integrated into such multivariate PCM frameworks. Here, originally motivated to analyze the complex evolutionary trajectories of group size (continuous variable) and social systems (discrete variable) in African subterranean rodents, we develop a flexible approach using approximate Bayesian computation (ABC). Specifically, our multivariate ABC-PCM method allows the user to flexibly model an underlying latent evolutionary function between continuous and discrete traits. The ABC-PCM also simultaneously incorporates complex evolutionary parameters such as branch-specific selection. This study highlights the flexibility of ABC-PCMs in analyzing the evolution of phenotypic traits interrelated in a complex manner.
KMT5C displays robust retention and liquid-like behavior in phase separated heterochromatin
Authors: Strickfaden Hilmar , Missiaen Kristal , Hendzel Michael J. , Underhill D. Alan
Published: September 2019

The pericentromere exists as a distinct chromatin compartment that is thought to form by a process of phase separation. This reflects the ability of the heterochromatin protein CBX5 (aka HP1α) to form liquid condensates that encapsulate pericentromeres.1,2 In general, phase separation compartmentalizes specific activities within the cell, but unlike membrane-bound organelles, their contents rapidly exchange with their surroundings.3 Here, we describe a novel state for the lysine methyltransferase KMT5C where it diffuses within condensates of pericentromeric heterochromatin but undergoes strikingly limited nucleoplasmic exchange, revealing a barrier to exit similar to that of biological membranes. This liquid-like behavior maps to a discrete protein segment with a small number of conserved sequence features and containing separable determinants for localization and retention that cooperate to confer strict spatial control. Accordingly, loss of KMT5C retention led to aberrant spreading of its catalytic product (H4K20me3) throughout the nucleus. We further found that KMT5C retention was reversible in response to chromatin state, which differed markedly for CBX5 and the methyl-CpG binding protein MeCP2, revealing considerable plasticity in the control of these phase separated assemblies. Our results establish that KMT5C represents a precedent in the biological phase separation4 continuum that confers robust spatial constraint of a protein and its catalytic activity without progression to a gel or solid.
ConnectedReads: machine-learning optimized long-range genome analysis workflow for next-generation sequencing
Authors: Su Chung-Tsai , Weng Sid , Li Yun-Lung , Chang Ming-Tai
Published: September 2019

Current human genome sequencing assays in both clinical and research settings primarily utilize short-read sequencing and apply resequencing pipelines to detect genetic variants. However, theses mapping-based data analysis pipelines remains a considerable challenge due to an incomplete reference genome, mapping errors and high sequence divergence. To overcome this challenge, we propose an efficient and effective whole-read assembly workflow with unsupervised graph mining algorithms on an Apache Spark large-scale data processing platform called ConnectedReads. By fully utilizing short-read data information, ConnectedReads is able to generate assembled contigs and then benefit downstream pipelines to provide higher-resolution SV discovery than that provided by other methods, especially in high diversity against reference and N-gap regions of reference. Furthermore, we demonstrate a cost-effective approach by leveraging ConnectedReads to investigate all spectra of genetic changes in population-scale studies.
Elastic strain tensor of zirconium hydrides in Zr2.5%Nb pressure tubes by synchrotron X-ray diffraction
Authors: Vicente Alvarez Miguel Angel , Santisteban Javier , Domizzi Gladys , Okasinski John , Almer Jonathan
Published: September 2019

Zirconium alloys are used in fuel cladding and structural components of nuclear power plants. Hydrogen enters the Zr matrix during plant operation and precipitates as hydride particles that degrade the mechanical properties of the alloy, limiting service life. Knowledge of the stress state within hydride precipitates is important to understand stress-induced degradation mechanisms such as delayed hydride cracking, but no direct quantification has yet been reported in the literature. Here, measurements are reported of the average elastic strain tensor within δ zirconium hydride precipitates in Zr2.5%Nb pressure tube material from CANDU power plants. Complete intensity and strain pole figures for the hydride were obtained by synchrotron X-ray diffraction experiments on specimens with hydrogen contents ranging from ∼100 wt p.p.m. hydrogen to nearly 100% δ-hydride. Zirconium hydride precipitates by a process involving a martensitic transformation, with two hydride variants possible from a single α-Zr grain. A synthetic model of the hydride crystallographic texture allowed the interpretation of the measured strain pole figures and quantification of the elastic strain tensor for both texture components. It was found that the two variants appear in nearly equal proportion but with different stress states, differing in the sign of the shear strain components (∼±3000 µɛ). This difference is possibly associated with the shear movement of Zr atoms during the phase transformation. This suggests that hydride clusters are composed of stacks of smaller hydrides in alternating hydride variants. Stresses were estimated from a set of rather uncertain hydride elastic constants. Overall, both variants showed compressive strains along the tube axial direction (∼5000 µɛ). For low hydrogen concentrations, the hydrides' stress tensor is dominated by compressive stresses of ∼300 MPa along the axial direction, probably caused by the elongated morphology of hydride clusters along this direction, and variant-dependent shear stresses of ∼±100 MPa, probably from the shear movement of the Zr atoms involved in the phase transformation.
High-resolution SAXS setup with tuneable resolution in direct and reciprocal space: a new tool to study ordered nanostructures
Authors: Chumakov Andrei P. , Napolskii Kirill S. , Petukhov Andrei V. , Snigirev Anatoly A. , Snigireva Irina I. , Roslyakov Ilya V. , Grigoriev Sergey V.
Published: September 2019

A novel compact small-angle X-ray scattering (SAXS) setup with tuneable resolution in both direct and reciprocal space has been designed and tested for the study of nanostructured materials with a hierarchical structure. The setup exploits a set of compound refractive lenses that focus the X-ray beam at the detector position. Anodic alumina membranes with a self-ordered porous structure were chosen as test samples. The setup allows patterns to be collected with a minimum scattering vector value of 0.001 nm−1 and gives the possibility for an easy continuous switch between taking high-resolution statistically averaged diffraction data of macroscopically large sample volumes and lower-resolution diffraction on a small single domain of the anodic aluminium oxide film. It is revealed that the pores are longitudinal and their ordering within each domain tends towards the ideal hexagonal structure, whereas the in-plane orientation of the pore arrays changes from domain to domain. The possible advantages and disadvantages of the proposed compact SAXS scheme are discussed.
The structure of bovine β-lactoglobulin in crystals grown at pH 3.8 exhibiting novel threefold twinning
Authors: Yeates Todd O. , McPherson Alexander
Published: September 2019

Bovine β-lactoglobulin was crystallized from 3 M NaCl buffered at pH 3.8 with sodium citrate as thick hexagonal prisms of greater than 1 mm in edge length. Analyses of the X-ray diffraction intensities using three different current algorithms were unanimous in specifying the space group to be P6322, with unit-cell dimensions a = b = 75.47, c = 140.79 Å. No progress could be made, however, towards an acceptable solution by molecular replacement using this symmetry. In the end, it was found that the true space group was C2221, a subgroup of P6322, with a = 65.89, b = 114.12, c = 140.51 Å, with the apparent 622 symmetry arising from an unusual threefold or tritohedral twinning. An assembly based on a model of the protein in another crystal form (PDB entry 1beb) containing three molecules in the asymmetric unit was refined to 2.3 Å resolution with a final R factor of 0.23 and R
free of 0.26. NCS restraints were maintained throughout. For the most part, the molecules found in this crystal form are virtually the same as in PDB entry 1beb, although there are numerous local variations, particularly in loop elements, rotamer conformation differences and some alterations, including additions, at the termini.
Crystal structure and Hirshfeld surface analysis of bis[hydrazinium(1+)] hexafluoridosilicate: (N2H5)2SiF6
Authors: Ouasri Ali , Lambarki Fatima , Rhandour Ali , Saadi Mohamed , El Ammari Lahcen
Published: September 2019

In the title inorganic molecular salt, (N2H5)2SiF6, the silicon atom at the centre of the slightly distorted SiF6 octahedron [range of Si—F distances = 1.6777 (4)–1.7101 (4) Å] lies on a crystallographic inversion centre. In the crystal, the ions are connected by N—H...N and N—H...F hydrogen bonds; the former link the cations into [010] chains and the latter (some of which are bifurcated or trifurcated) link the ions into a three-dimensional network. The two-dimensional fingerprint plots show that F...H/H...F interactions dominate the Hirshfeld surface (75.5%) followed by H...H (13.6%) and N...H/H...N (8.4%) whereas F...F (1.9%) and F...N/N...F (0.6%) have negligible percentages. The title compound is isostructural with its germanium-containing analogue.
Crystal structure and Hirshfeld surface analysis of 3-(cyclopropylmethoxy)-4-(difluoromethoxy)-N-(pyridin-2-ylmethyl)benzamide
Authors: Artheswari G. , Maheshwaran V. , Gautham N.
Published: September 2019

The title compound, C18H18F2N2O3, crystallizes with two independent molecules (A and B) in the asymmetric unit. They differ essentially in the orientation of the pyridine ring with respect to the benzene ring; these two rings are inclined to each other by 53.3 (2)° in molecule A and by 72.9 (2)° in molecule B. The 3-(cyclopropylmethoxy) side chain has an extended conformation in both molecules. The two molecules are linked by a pair of C—H...O hydrogen bonds and two C—H...π interactions, forming an A–B unit. In the crystal, this unit is linked by N—H...O hydrogen bonds, forming a zigzag –A–B–A–B– chain along [001]. The chains are linked by C—H...N and C—H...F hydrogen bonds to form layers parallel to the ac plane. Finally, the layers are linked by a third C—H...π interaction, forming a three-dimensional structure. The major contributions to the Hirshfeld surface are those due to H...H contacts (39.7%), followed by F...H/H...F contacts (19.2%).
Differential geometry of autonomous wheel-legged robots
Authors: Bulut Vahide
Published: September 2019

Purpose

The purpose of this study is to obtain the differential geometric analysis of autonomous wheel-legged robots and their trajectories on the terrain.

Design/methodology/approach

The author uses a wheel using the osculating sphere of the curve on rough terrain. Additionally, the author expresses a triple osculating sphere wheel by taking advantage of differential geometry. Moreover, the author examined the consecutive wheel center-curves to obtain the optimum posture of a micro-hydraulic toolkit (MHT) robot.

Findings

The author examined the terrain path, which is crucial for trajectory planning in terms of the geometric perspective. The author designed the triple MHT wheel using the osculating sphere of the MHT robot trajectory by taking advantage of local differential geometric properties of this curve on the terrain. The consecutive wheel center-curves were expressed and studied based on differential geometry.

Originality/value

The author provides a novel approach for the optimum posture of an MHT robot using consecutive wheel-center curves and provides an original perspective to MHT robot and its trajectory by using differential geometry.
Success and agency: localizing women’s leadership in Oman
Authors: Hallward Maia , Bekdash-Muellers Hania
Published: September 2019

Purpose

This study aims to examine women’s leadership in Oman, seeking to empirically determine whether and how local perceptions of “success” and lifestyle preferences are related to women’s agency and propensity for leadership.

Design/methodology/approach

Drawing on the literature, this paper qualitatively analyzes 32 semi-structured interviews of diverse Omani women leaders, identifying their conceptions of success as predominantly subjective or objective. At the same time, the study uses Hakim’s (2006) lifestyle preference model to explore women's agency.

Findings

Contrary to the literature on the central importance of domestic responsibilities for Arab Muslim women, more women in leadership positions are identified as career-centered (14/32, 44%); those who did identify as family-centered (6/32, 19%) did not cite Islam to justify that preference, and success is envisioned more subjectively (19/32, 59%).

Research limitations/implications

The sample has an urban bias and does not claim to be representative of all Omani women. Interviews were conducted in English; most women leaders in Oman are required to speak English.

Practical implications

By analyzing work-life balance preferences as a proxy for agency and interrogating Omani women's own conceptions of success, the study may lead to more robust and culturally aware policies to support women’s leadership.

Social implications

Defining in subjective terms suggests that success is not necessarily equated with achieving a high level position for Omani women. Further, only 6/32 were identified as home-centered, thus indicating the critical importance of domestic support from hired labor or family members.

Originality/value

This study contributes new empirical findings on women leaders in Oman that illustrates the role of personal agency and lifestyle preference in contrast to many studies that treat culture as a constant.
A coupled LES-Monte Carlo method for simulating aerosol dynamics in a turbulent planar jet
Authors: Liu Hongmei , Chan Tat Leung
Published: September 2019

Purpose

The purpose of this paper is to study the evolution and growth of aerosol particles in a turbulent planar jet by using the newly developed large eddy simulation (LES)-differentially weighted operator splitting Monte Carlo (DWOSMC) method.

Design/methodology/approach

The DWOSMC method is coupled with LES for the numerical simulation of aerosol dynamics in turbulent flows.

Findings

Firstly, the newly developed and coupled LES-DWOSMC method is verified by the results obtained from a direct numerical simulation-sectional method (DNS-SM) for coagulation occurring in a turbulent planar jet from available literature. Then, the effects of jet temperature and Reynolds number on the evolution of time-averaged mean particle diameter, normalized particle number concentration and particle size distributions (PSDs) are studied numerically on both coagulation and condensation processes. The jet temperature and Reynolds number are shown to be two important parameters that can be used to control the evolution and pattern of PSD in an aerosol reactor.

Originality/value

The coupling between the Monte Carlo method and turbulent flow still encounters many technical difficulties. In addition, the relationship between turbulence, particle properties and collision kernels of aerosol dynamics is not yet well understood due to the theoretical limitations and experimental difficulties. In the present study, the developed and coupled LES-DWOSMC method is capable of solving the aerosol dynamics in turbulent flows.
Filling in the gaps in higher education quality
Authors: Cavallone Mauro , Manna Rosalba , Palumbo Rocco
Published: September 2019

Purpose

It is not easy to grasp the concept of “value” in the higher education context. In fact, different stakeholders generally hold diverging perspectives about the value generated by Higher Education Institutions (HEIs). The purpose of this paper is to disentangle the value expectations and perceptions of current and former students (i.e. the main stakeholders) of a medium-sized university established in Northern Italy.

Design/methodology/approach

A mixed, qualitative–quantitative case study was undertaken. A semi-structured survey was delivered through a computer-assisted web interview technique to a sample of 2,572 people. Inter alia, the interviewees were asked to express their value perceptions and value expectations toward the case institution and to rate their own assessment of educational services’ quality.

Findings

The respondents felt that the university was effective in delivering functional, extrinsic and intrinsic value; conversely, they perceived several gaps in the case institution’s ability to accomplish emotional and relational value. Moreover, the interviewees argued that the institution was unsuccessful in establishing a bridge between higher education and the labor market, focussing on conceptual issues, rather than on experiential learning and soft skills.

Practical implications

The gap between the students’ value expectations and perceptions hampers the perceived quality of educational services. The lack of awareness of this gap is thought to trigger organizational inertia, which contributes to the impoverishment of educational services’ quality.

Originality/value

The paper sheds light on different value perceptions and expectations held by students of a medium-sized HEI; also, it provides some insights into the organizational and management implications of diverging value perceptions and expectations of students.
Impact evaluation of Literacy Boost Project Model on reading skills of early grade students in Ethiopia
Authors: Kumsa Kassahun , Tesfahun Azmeraw Ayehu , Legas Habtamu Adane
Published: September 2019

Purpose

The purpose of this paper is to assess the impact of Literacy Boost Project Model implemented by World Vision on reading skills of early grade students in Ethiopia. It intended to examine whether the intervention contributed to improving students’ achievement in reading comprehension.

Design/methodology/approach

Difference in difference with propensity score matching impact estimation model was used in the study. Baseline and end line data collected by World Vision Ethiopia in four districts in Oromia region, where the project had been operational, were used for the research. A total of 1,418 students (685 control and 733 intervention) were selected using random sampling technique and assessed based on the core reading skill components.

Findings

The result of the analysis indicated significant improvement in the core reading skills of treated students. The ultimate outcome of reading comprehension skill from the previous evaluation was found inflated. Variables related to the home literacy environment and community activities were found significantly impacting the students reading achievement.

Research limitations/implications

Policies and strategies intended to improve the quality of education, particularly the reading skills of early grade students, in the study area and scaling up the literacy boost project to areas with similar context, thus should give due attention to the variables related to the home literacy environment and community activities.

Originality/value

This study is important in providing valuable information on early grade education quality improvement interventions, especially to development practitioners and policymakers to make informed decisions regarding education sector reform and development in the study area.
The transition of small Spanish wineries toward multi-channel distribution
Authors: Calderón Haydeé , Fayos Teresa , Frasquet Marta
Published: September 2019

Purpose

This paper aims to analyses the development of exploitation and exploration capabilities, and the role of ambidexterity, in the evolution of small Spanish wineries toward multi-channel distribution systems.

Design/methodology/approach

A qualitative methodology based on the analyses of multiple cases supported by a computer assisted qualitative data analysis software with an abductive approach was used to study the relationship between ambidexterity and the multi-channel integration of six wineries.

Findings

Companies with more advanced multi-channel distribution systems have more developed ambidexterity capabilities. This ambidexterity stems fundamentally from the ability to simultaneously maintain relations with distributors and innovate and search for creative ways to satisfy new customers.

Research limitations/implications

The research is based on insights from companies based in Spain.

Practical implications

Spanish small and medium enterprises in the sector are in an underdeveloped phase of multi-channel integration. To be successful in this process, these companies must combine exploitation and exploration capabilities.

Social implications

If the company is able to develop an integrated multi-channel distribution system leading to an omnichannel system, consumers will benefit from it, getting complete information at each specific stage of shopping.

Originality/value

This study provides the first description in academic literature of the usefulness of the concept of ambidexterity as a dynamic capability to explain the degree of development and multi-channel integration.
Implementation of a Web interface for hybrid intelligent systems
Authors: Sakamoto Shinji , Barolli Admir , Barolli Leonard , Okamoto Shusuke
Published: September 2019

Purpose

The purpose of this paper is to implement a Web interface for hybrid intelligent systems. Using the implemented Web interface, this paper evaluates two hybrid intelligent systems based on particle swarm optimization, hill climbing and distributed genetic algorithm to solve the node placement problem in wireless mesh networks (WMNs).

Design/methodology/approach

The node placement problem in WMNs is well-known to be a computationally hard problem. Therefore, the authors use intelligent algorithms to solve this problem. The implemented systems are intelligent systems based on meta-heuristics algorithms: Particle Swarm Optimization (PSO), Hill Climbing (HC) and Distributed Genetic Algorithm (DGA). The authors implement two hybrid intelligent systems: WMN-PSODGA and WMN-PSOHC-DGA.

Findings

The authors carried out simulations using the implemented Web interface. From the simulations results, it was found that the WMN-PSOHC-DGA system has a better performance compared with the WMN-PSODGA system.

Research limitations/implications

For simulations, the authors considered Normal distribution of mesh clients. In the future, the authors need to consider different client distributions, patterns, number of mesh nodes and communication distance.

Originality/value

In this research work, the authors implemented a Web interface for hybrid intelligent systems. The implemented interface can be extended for other metaheuristic algorithms.
What affects length of hospital stay? A case study from Malta
Authors: Abela Lorraine , Pace Adriana , Buttigieg Sandra C.
Published: September 2019

Purpose

Hospital length of stay (LOS) is not only a function of patient- and disease-related factors, but is also determined by other health system-wide variables. Managers and clinicians strive to achieve the best possible trade-off between patients’ needs and efficient utilisation of hospital resources, while also embracing ethical decision making. The purpose of this paper is to explore the perceptions of the hospital’s major stakeholders as to what affects the duration of LOS of inpatients.

Design/methodology/approach

Using a data-triangulated case study approach, 50 semi-structured interviews were performed with management, doctors, nurses and patients. Additionally, the hospitals’ standard operating procedures, which are pertinent to the subject, were also included in the thematic analysis.

Findings

This study shows that LOS is a multi-dimensional construct, which results from a complex interplay of various inputs, processes and outcomes.

Research limitations/implications

The findings emerging from a single case study approach cannot be generalised across settings and contexts, albeit being in line with the current literature.

Practical implications

The study concludes that a robust hospital strategy, which addresses deficient organisational processes that may unnecessarily prolong LOS, is needed. Moreover, the hospital’s strategy must be sustained by providing good primary care facilities within the community set-up, as well as by providing more long-term care and rehabilitation beds to support the hospital turnover.

Originality/value

The subject of LOS in hospitals has so far been tackled in a fragmented manner. This paper provides a comprehensive and triangulated account of the complexities surrounding the duration in which patients are kept in hospital by key stakeholders, most of whom were hands-on in the day-to-day running of the hospital under study.
Leadership self-efficacy: review and leader development implications
Authors: Dwyer Laura Paglis
Published: September 2019

Purpose

The purpose of this paper, on self-efficacy and leadership, has two objectives. First, it comprehensively reviews approximately 25 years of research on leadership self-efficacy (LSE), beginning with LSE measurement and related criticisms. Findings concerning LSE’s relationships with leader effectiveness criteria, as well as individual and contextual influences on LSE, are presented. Second, it examines the evidence on efficacy enhancement interventions and offers some preliminary recommendations for increasing LSE through leadership development programs.

Design/methodology/approach

The author conducted a comprehensive literature review of the existing research on LSE, covering the main contributors to this research stream and their findings.

Findings

The review revealed substantial diversity in LSE construct development and measurement approaches. Regarding LSE and leader effectiveness, many studies reported positive relationships with potential, performance and behavioral ratings of leaders. Collective (team) efficacy has emerged as a significant mediator between LSE and group performance. Influences on LSE include several of the Big Five personality traits, while contextual antecedents are under-researched, and potentially fruitful areas for further study. Executive coaching and mentoring, as well as cognitive modeling techniques and training in constructive thought patterns, received support for enhancing LSE in developing leaders.

Originality/value

This paper’s review and implications should be of substantial value to current and future LSE researchers, as it summarizes past research, synthesizes the findings to draw out common themes and consistent, corroborated findings, and identifies opportunities for future research. For practitioners, the reviewed research on interventions for increasing LSE through leadership development programs provides practical guidance.
High-performance work system practices in Vietnam: a study of managers’ perceptions
Authors: Do Hoa , Budhwar Pawan , Patel Charmi
Published: September 2019

Purpose

The purpose of this paper is to explore the effects of high-performance work systems (HPWS) on the performance of Vietnamese firms. It teases out the antecedents and effects of managers’ beliefs about why HPWS exist and are adopted within their firms, and also what effects HPWS practices have on their firm’s performance.

Design/methodology/approach

The authors adopt a longitudinal design to provide insights into why and how HPWS are shaped and diffused, and also how they convert the inputs into outputs such as HR outcomes, firm innovation and performance, based on a sample of 17 in-depth interviewees who were CEOs, HR managers, general managers in 17 Vietnamese service firms.

Findings

Results demonstrate that HPWS can impact both employee outcomes (e.g. employee attitudes, behaviours and productivity), and firm performance (e.g. firm innovation, firm growth and profit growth).

Practical implications

The study underscores the importance of HPWS as a response to organizational change that can help deal with external pressures and provides evidence about how the HPWS-innovation relationship is established in the research context.

Originality/value

This is among the first study to extend some aspects of institutional theory to understand the context of how and why HPWS are shaped and executed to respond to environmental pressures. It underscores the importance of HPWS as a response to organizational change that can help deal with external pressures, thereby serving as a leading step to yield meaningful outcomes with respect to the advancement of this research stream.