bluuebunny/crossref_metadata_2025 huggingface dataset:
Treatment-Specific Composition of Gut Microbiota Is Associated with Disease Remission in a Pediatric Crohn’s Disease Cohort
Authors: Sprockett Daniel , Fischer Natalie , Boneh Rotem Sigall , Turner Dan , Kierkus Jarek , Sladek Malgorzata , Escher Johanna C. , Wine Eytan , Yerushalmi Baruch , Dias Jorge Amil , Shaoul Ron , Kori Michal , Snapper Scott B. , Holmes Susan , Bousvaros Athos , Levine Arie , Relman David A.
Published: September 2018

Background

The beneficial effects of antibiotics in Crohn’s disease (CD) depend in part on the gut microbiota but are inadequately understood. We investigated the impact of metronidazole (MET) and metronidazole plus azithromycin (MET+AZ) on the microbiota in pediatric CD, and the use of microbiota features as classifiers or predictors of disease remission.

Methods

16S rRNA-based microbiota profiling was performed on stool samples from 67 patients in a multinational, randomized, controlled, longitudinal, 12-week trial of MET vs. MET+AZ in children with mild to moderate CD. Profiles were analyzed together with disease activity, and then used to construct Random Forest models to classify remission or predict treatment response.

Results

Both MET and MET+AZ significantly decreased diversity of the microbiota and caused large treatment-specific shifts in microbiota structure at week 4. Disease remission was associated with a treatment-specific microbiota configuration. Random Forest models constructed from microbiota profiles pre- and during antibiotic treatment with metronidazole accurately classified disease remission in this treatment group (AUC of 0.879, 95% CI 0.683, 0.9877; sensitivity 0.7778; specificity 1.000, P < 0.001). A Random Forest model trained on preantibiotic microbiota profiles predicted disease remission at week 4 with modest accuracy (AUC of 0.8, P = 0.24).

Conclusions

MET and MET+AZ antibiotic regimens in pediatric CD lead to distinct gut microbiota structures at remission. It may be possible to classify and predict remission based in part on microbiota profiles, but larger cohorts will be needed to realize this goal.

We investigated the impact of metronidazole and metronidazole plus azithromycin on the gut microbiota in pediatric Crohn’s disease. Disease remission was associated with a treatment-specific microbiota configuration, and could be predicted based on pre-antibiotic microbiota profiles.
Maternal inflammation has a profound effect on cortical interneuron development in a stage and subtype-specific manner
Authors: Vasistha Navneet A. , Pardo-Navarro Maria , Gasthaus Janina , Weijers Dilys , Müller Michaela K. , García-González Diego , Malwade Susmita , Korshunova Irina , Pfisterer Ulrich , von Engelhardt Jakob , Hougaard Karin S. , Khodosevich Konstantin
Published: September 2018

Severe infections during pregnancy are one of the major risk factors for cognitive brain impairment in offspring. It has been suggested that maternal inflammation leads to dysfunction of cortical GABAergic interneurons that in turn underlies cognitive impairment of the affected offspring. However, the evidence comes largely from studies of adult or mature brain and how impairment of inhibitory circuits arises upon maternal inflammation is unknown. Here we show that maternal inflammation affects multiple steps of cortical GABAergic interneuron development, i.e. proliferation of precursor cells, migration and positioning of neuroblasts as well as neuronal maturation. Importantly, the development of distinct subtypes of cortical GABAergic interneurons was discretely impaired as a result of maternal inflammation. This translated into a reduction in cell numbers, redistribution across cortical regions and layers, changes in morphology and cellular properties. Furthermore, selective vulnerability of GABAergic interneuron subtypes was associated with the stage of brain development. Thus, we propose that maternally-derived insults have developmental stage-dependent effects which contribute to the complex etiology of cognitive impairment in the affected offspring.
Inter-individual differences in human brain structure and morphometry link to population variation in demographics and behavior
Authors: Llera A. , Wolfers T. , Mulders P. , Beckmann C. F.
Published: September 2018

We perform a comprehensive integrative analysis of multiple structural MR-based brain features and find strong evidence relating inter-individual structural variations to demographic and behavioral variates across a large cohort of healthy human volunteers. In particular, our findings shed some light on functional & structural integration, as we find a mode of structural variation that relates to and extends the ‘positive-negative’ behavioral spectrum which was recently reported as being associated with variations in functional connectivity.

Significance statement

This work provides for the first-time strong evidence relating human brain structure variations to a wide range of demographic and behavioral measures. We show that several measures previously associated to variation in functional MRI connectivity are in fact already associated at the structural level, pointing towards structure-function integration.
Checkpoint kinase 1 is essential for establishing fetal haematopoiesis and hematopoietic stem and progenitor cell survival
Authors: Schuler Fabian , Afreen Sehar , Manzl Claudia , Häcker Georg , Erlacher Miriam , Villunger Andreas
Published: September 2018

Checkpoint kinase 1 is critical for S-phase fidelity and preventing premature mitotic entry in the presence of DNA damage. Tumour cells have developed a strong dependence on CHK1 for survival and hence this kinase has developed into a popular drug-target.Chk1-deficiency in mice results in blastocyst death due to G2/M checkpoint-failure showing that it is an essential gene and may be difficult to target therapeutically without side-effects. Here, we show that chemical inhibition of CHK1 kills murine hematopoietic stem and progenitor cells (HSPCs) as well as human CD34+HSPCs by the induction of BCL2-regulated but p53-independent apoptosis. Moreover,Chk1is essential for stem cell survival and definite hematopoiesis in the mouse embryo. Remarkably though, cell death inhibition in hematopoietic stem cells (HSC) cannot restore blood cell formationin uteroasChk1loss causes severe DNA damage that ultimately prevents HSC expansion. Our findings establish a previously unrecognized role for CHK1 in establishing hematopoiesis; they also suggest adverse effects of therapeutic CHK1-inhibtion, particularly under conditions forcing stem cells out of dormancy, such as chemotherapy-induced myelosuppression.
Protein Multiple Alignments: Sequence-based vs Structure-based Programs
Authors: Carpentier Mathilde , Chomilier Jacques
Published: September 2018

Facing the huge increase of information about proteins, classification has reached the level of a compulsory task, essential for assigning a function to a given sequence, by means of comparison to existing data. Multiple sequence alignment programs have been proven to be very useful and they have already been evaluated. In this paper we wished to evaluate the added value provided by taking into account structures. We compared the multiple alignments resulting from 24 programs, either based on sequence, structure, or both, to reference alignments deposited in five databases. Reference databases, on their side, can be split in two: more automatic ones, and more manually ones. Scores have been attributed to each program. As a global rule of thumb, five groups of methods emerge, with the lead to two of the structure-based programs. This advantage is increased at low levels of sequence identity among aligned proteins, or for residues in regular secondary structures or buried. Concerning gap management, sequence-based programs place less gaps than structure-based programs. Concerning the databases, the alignments from the manually built databases are the more challenging for the programs.
The role of BMP6 in the proliferation and differentiation of chicken cartilage cells
Authors: Ye Fei , Xu Hengyong , Yin Huadong , Zhao Xiaoling , Li Diyan , Zhu Qing , Wang Yan
Published: September 2018

Previous studies have indicated that bone morphogenetic protein (BMP) 6 plays an important role in skeletal system development and progression. However, the mechanism underlying the effects of BMP6 in cartilage cell proliferation and differentiation remains unknown. In this study, cartilage cells were isolated from shanks of chicken embryos and treated with different concentrations of GH. Cell proliferation and differentiation potential was assessed using real-time polymerase chain reaction (RT-PCR) and CCK-8 assays in vitro. The results showed that at 48 h, the Collagen II and BMP6 expression levels in 50 ng/μl GH-treated cartilage cells were significantly higher than in groups treated with 100 ng/μl or 200 ng/μl GH. We further observed that knockdown of BMP6 in cartilage cells led to significantly decreased expression levels of Collagen II and Collagen X. Moreover, the suppression of BMP6 expression by a specific siRNA vector led to significantly decreased expression levels of IGF1R, JAK, PKC, PTH, IHH and PTHrP. Taken together, our data suggest that BMP6 may play a critical role in chicken cartilage cell proliferation and differentiation through the regulation of IGF1, JAK2, PKC, PTH, and Ihh-PTHrP signaling pathways.
Glutathione S-Transferase Genotype polymorphism and Primary Open-Angle Glaucoma in an Italian population
Authors: Saccà Sergio C , Cutolo Carlo A , Gandolfi Stefano , Marchini Giorgio , Quaranta Luciano , Izzotti Alberto , Rossi Tommaso , Traverso Carlo Enrico
Published: September 2018

Purpose

Oxidative damage to the trabecular meshwork (TM) represents one of the pathogenic mechanisms leading to primary open angle glaucoma (POAG). Glutathione S-transferase mu 1 (GSTM1) may neutralizes reactive oxygen species protecting the TM. The present paper investigates the prevalence of GSTM1 null genotype in an Italian population, and its association with POAG treated either medically or surgically.

Methods

In a case-control study, the GSTM1 genotype was identified in POAGs and controls. The POAGs patients were divided in two groups: medical POAGs and surgical POAGS. Medical POAGs consisted of patients with a well-controlled intraocular pressure (IOP) by IOP-lowering medications and a stable visual field (VF). Patients with an uncontrolled IOP and a progressing VF that were submitted to incisional surgery formed the surgical POAGs’ group.

Results

We enrolled 104 medical POAGs, 158 surgical POAGs and 263 Controls. No significative differences between the groups existed regarding age and gender (p=0.275 and p=0.950, respectively). All the enrolled subjects were Caucasian of Italian descents. The GSTM1 null genotype was identified in 57 (45.2%) medical POAGs, 91 (57.6%) surgical POAGs and, 119 (45.3%) controls (p=0.033). The association between medical POAG and GSTM1 null status was non-significant (OR= 1.44, 95% IC = 0.86 to 2.39) whereas the association was significant for surgical POAGs (OR= 2.01, 95% IC= 1.26 to 3.21)

Conclusions

Our results showed an association between the GSTM1 null genotype and glaucoma that require surgery in an Italian population. GSTM1 null genotype detection may help to identify high-risk glaucoma patients that require a closer follow-up and a more aggressive treatments.
Sea lettuce systematics: lumping or splitting?
Authors: Batista Manuela Bernardes , Cunha Regina L. , Castilho Rita , Horta Paulo Antunes
Published: September 2018

Phylogenetic relationships within sea lettuce species belonging to the genusUlvais a daunting challenge given the scarcity of diagnostic morphological features and the pervasive phenotypic plasticity. With more than 100 species described on a morphological basis, an accurate evaluation of its diversity is still missing. Here we analysed 277 chloroplast-encoded gene sequences (43 from this study), representing 35 nominal species ofUlvafrom the Pacific, Indian Ocean, and Atlantic (with a particular emphasis on the Brazilian coast) in an attempt to solve the complex phylogenetic relationships within this widespread genus. Maximum likelihood, Bayesian analyses and species delimitation tests support the existence of 22 evolutionary significant units (ESUs), lumping the currently recognized number of species. All individuals sampled throughout an extensive area of the Brazilian coast were included within two distinct ESUs. Most of the clades retrieved in the phylogenetic analyses do not correspond to a single nominal species. Geographic range evolution indicated that the ancestor ofUlvahad a distribution restricted to the temperate North Pacific. The dating analysis estimated its origin during the Upper Cretaceous at 75.8 million years (myr) ago but most of the cladogenetic events within the genus occurred in the last ten myr. Pervasive human-mediated gene flow through ballast water and widespread morphologic plasticity are the most likely explanations for the difficulty in establishing a reliable phylogenetic framework for this conspicuous, widespred and many times abundant green algae morphotype.
HLA RNAseq reveals high allele-specific variability in mRNA expression
Authors: Johansson Tiira , Yohannes Dawit A. , Koskela Satu , Partanen Jukka , Saavalainen Päivi
Published: September 2018

The HLA gene complex is the most important, single genetic factor in susceptibility to most diseases with autoimmune or autoinflammatory origin and in transplantation matching. The majority of the studies have focused on the huge allelic variation in these genes; only a few studies have explored differences in expression levels of HLA alleles. To study the expression levels of HLA alleles more systematically we utilised two different RNA sequencing methods. Illumina RNAseq has a high sequencing accuracy and depth but is limited by the short read length, whereas Oxford Nanopore’s technology can sequence long templates, but has a poor accuracy. We studied allelic mRNA levels of HLA class I and II alleles from peripheral blood samples of 50 healthy individuals. The results demonstrate large differences in mRNA expression levels between HLA alleles. The method can be applied to quantitate the expression differences of HLA alleles in various tissues and to evaluate the role of this type of variation in transplantation matching and susceptibility to autoimmune diseases.

Author Summary

Even though HLA is widely studied less is known of its allele-specific expression. Due to the pivotal role of HLA in infection response, autoimmunity, and transplantation biology its expression surely must play a part as well. In hematopoietic stem cell transplantation the challenge often is to find a suitable HLA-matched donor due to the high allelic variation. Classical HLA typing methods do not take into account HLA allele-specific expression. However, differential allelic expression levels could be crucial in finding permissive mismatches in order to save a patient’s life. Additionally, differential HLA expression levels can lead into beneficial impact in viral clearance but also undesirable effects in autoimmune diseases. To study HLA expression we developed a novel RNAseq-based method to systematically characterize allele-specific expression levels of classical HLA genes. We tested our method in a set of 50 healthy individuals and found differential expression levels between HLA alleles as well as interindividual variability at the gene level. Since NGS is already well adopted in HLA research the next step could be to determine HLA allele-specific expression in addition to HLA allelic variation and HLA-disease association studies in various cells, tissues, and diseases.
Coverage-based detection of copy number alterations in mixed samples using DNA sequencing data: a theoretical framework for evaluating statistical power
Authors: Ramdas Shweta , Pan Yanchao , Li Jun Z
Published: September 2018

1

DNA sequencing can discover not only single-base variants but also copy-number alterations (CNAs). In shotgun sequencing, regions of CNAs show step-wise changes in read depth when compared to adjacent “normal” regions, allowing their detection by parametric statistical tests that compare the mean coverage in suspected regions against that of a baseline distribution. Traditionally, the power of such a test depends on (1) the integer number of copy number change, (2) the overall sequencing depth, (3) the length of the CNA region, (4) the read length and (5) the variation of coverage along the genome, which depends on many experimental factors, including whether the chosen platform is whole-genome, whole-exome, or targeted-panel sequencing. In cases involving inadvertent sample mixing or genuine somatic mosaicism, power also depends on the mixing ratio. However, the analysis of statistical power that considers the interplay of all these factors has not been systematically developed. Here we present a general analytical framework and a series of simulations that explore situations from the simplest to the increasingly multifactorial. Specifically, we expand the expression of power to include not just the known factors but also one or both of two complications: (1) the dispersion of read depth around the mean beyond the independent sampling-by-sequencing assumption, and (2) the reduced fraction of the CNA-bearing sample (“purity”) as seen in studies of intratumor heterogeneity or in clinical monitoring of minimal residual disease. We describe the analytical formula and their simplifications in special cases, and share the extendable scripts for others to perform customized power analysis using study-specific parameters. As study designs vary and technologies continue to evolve, the input data and the noise characteristics will change depending on the practical situation. We present two use cases commonly encountered in cancer research: ultra-shallow whole-genome sequencing for detecting large, chromosome-scale events, and targeted ultra-deep sequencing for surveillance of known CNAs in rare tumor clones in the task of sensitive detection of cancer relapse or metastasis. We also present an online calculator at https://shiny.med.umich.edu/apps/hanyou/CNV_Detection_Power_Calculator/.
Membrane insertion function for SUN-KASH complex revealed by high resolution analysis of yeast centrosomes
Authors: Chen Jingjing , Gardner Jennifer M. , Yu Zulin , Smith Sarah E. , McKinney Sean , Slaughter Brian D. , Unruh Jay R. , Jaspersen Sue L.
Published: September 2018

Bipolar spindle formation in yeast requires insertion of centrosomes (known as spindle pole bodies (SPBs)) into fenestrated regions of the nuclear envelope (NE). Using structured-illumination microscopy and bimolecular fluorescence complementation, we map protein distribution at SPB fenestra and interrogate protein-protein interactions with high spatial resolution. We find that the Sad1-UNC-84 (SUN) protein Mps3 forms a ring-like structure around the SPB, similar to toroids seen for components of the SPB insertion network (SPIN). Mps3 and the SPIN component Mps2 (a Klarsicht-ANC-1-Syne-1 domain (KASH)-like protein) form a novel non-canonical linker of nucleoskeleton and cytoskeleton (LINC) complex that is connected in both luminal and extraluminal domains. This hairpin-like LINC complex forms during SPB insertion, suggesting it functions in NE reorganization at the pore membrane. The LINC complex also controls the distribution of a soluble SPIN component Bbp1. Taken together our work shows that Mps3 is a fifth SPIN component and suggests both direct and indirect roles for the LINC complex in NE remodeling.
Transsaccadic feature interactions in multiple reference frames: an fMRIa study
Authors: Baltaretu Bianca R. , Dunkley Benjamin T. , Monaco Simona , Chen Ying , Crawford J.Douglas
Published: September 2018

Transsaccadic integration of visual features can operate in various frames of reference, but the corresponding neural mechanisms have not been differentiated. A recent fMRIa (adaptation) study identified two cortical regions in supramarginal gyrus (SMG) and extrastriate cortex that were sensitive to transsaccadic changes in stimulus orientation (Dunkley et al., 2016). Here, we modified this paradigm to identify the neural correlates for transsaccadic comparison of object orientations in: 1) Spatially Congruent (SC), 2) Retinally Congruent (RC) or 3) Spatially Incongruent (SI)) coordinates. Functional data were recorded from 12 human participants while they observed a grating (oriented 45° or 135°) before a saccade, and then judged whether a post-saccadic grating (in SC, RC, or SI configuration) had the same or different orientation. Our analysis focused on areas that showed a significant repetition suppression (Different > Same) or repetition enhancement (Same > Different) BOLD responses. Several cortical areas were significantly modulated in all three conditions: premotor/motor cortex (likely related to the manual response), and posterior-middle intraparietal sulcus. In the SC condition, uniquely activated areas included left SMG and left lateral occipitotemporal gyrus (LOtG). In the RC condition, unique areas included inferior frontal gyrus and the left lateral BA 7. In the SI condition, uniquely activated areas included the frontal eye field, medial BA 7, and right LOtG. Overall, the SC results were significantly different from both RC and SI. These data suggest that different cortical networks are used to compare pre- and post-saccadic orientation information, depending on the spatial nature of the task.

Significance Statement

Every time one makes a saccade, the brain must compare and integrate stored visual information with new information. It has recently been shown that ‘transsaccadic integration’ of visual object orientation involves specific areas within parietal and occipital cortex (Dunkley et al., 2016). Here, we show that this pattern of cortical activation also depends on the spatial nature of the task: when the visual object is fixed relative to space, the eye, or relative to neither space nor the eye, different frontal, parietal, and occipital regions are engaged. More generally, these findings suggest that different aspects of trans-saccadic integration flexibly employ different cortical networks.
C57BL/6 substrain differences in inflammatory and neuropathic nociception and genetic mapping of a major quantitative trait locus underlying acute thermal nociception
Authors: Bryant Camron D. , Bagdas Deniz , Goldberg Lisa R. , Khalefa M. Tala , Reed M.Eric R. , Kirkpatrick Stacey L. , Kelliher Julia C. , Chen Melanie M. , Johnson William E. , Mulligan Megan K. , Damaj M. Imad
Published: September 2018

Sensitivity to different pain modalities has a genetic basis that remains largely unknown. Employing closely related inbred mouse substrains can facilitate gene mapping of nociceptive behaviors in preclinical pain models. We previously reported enhanced sensitivity to acute thermal nociception in C57BL/6J (B6J) versus C57BL/6N (B6N) substrains. Here, we expanded on nociceptive phenotypes and observed an increase in formalin-induced inflammatory nociceptive behaviors and paw diameter in B6J versus B6N mice (Charles River Laboratories). No strain differences were observed in mechanical or thermal hypersensitivity or in edema following the Complete Freund’s Adjuvant (CFA) model of inflammatory pain, indicating specificity in the inflammatory nociceptive stimulus. In the chronic nerve constriction injury (CCI), a model of neuropathic pain, no strain differences were observed in baseline mechanical threshold or in mechanical hypersensitivity up to one month post-CCI. We replicated the enhanced thermal nociception in the 52.5°C hot plate test in B6J versus B6N mice from The Jackson Laboratory. Using a B6J x B6N-F2 cross (N=164), we mapped a major quantitative trait locus (QTL) underlying hot plate sensitivity to chromosome 7 that peaked at 26 Mb (LOD=3.81, p<0.01; 8.74 Mb-36.50 Mb) that was more pronounced in males. Genes containing expression QTLs (eQTLs) associated with the peak nociceptive marker that are implicated in pain and inflammation include Ryr1, Cyp2a5, Pou2f2, Clip3, Sirt2, Actn4, and Ltbp4 (FDR < 0.05). Future studies involving positional cloning and gene editing will determine the quantitative trait gene(s) and potential pleiotropy of this locus across pain modalities.
Characterisation and development of aspirin inducible biosensors inE. coliNissle 1917 and SimCells
Authors: Chen Jack Xiaoyu , Steel Harrison , Wu Yin-Hu , Wang Yun , Xu Jiabao , Rampley Cordelia P. N. , Thompson Ian P. , Papachristodoulou Antonis , Huang Wei E.
Published: September 2018

A simple aspirin-inducible system has been developed by employing the Psalpromoter and SalR regulation system originally fromAcinetobacter baylyiADP1, which has been cloned intoE. colifor characterisation of gene circuits and induction of novel SimCells (simple cells). Mutagenesis at the DNA binding domain (DBD) and chemical recognition domain (CRD) of the SalR protein inA. baylyiADP1 suggests that inactive SalRican compete with activated SalRa, occupying the binding position of Psalpromoter. The induction of the Psalpromoter was compared in two different designs inE. coli: simple regulation (SRS) and positive autoregulated system (PAR). Both regulatory systems were induced in a dose-dependent manner in the presence of aspirin in the range of 0.05-10 μM. Over-expression of SalR in the SRS system reduces both baseline leakiness and inducible strength of Psalpromoter. A weak SalR expression significantly improve the inducible strength, which is in a good agreement of the proposed hypothesis of SalRi/SalRacompetitive binding. The PAR system provides a feedback loop that fine-tunes the level of SalR, displaying inducible strength. A mathematical model based on SalRi/SalRacompetitive binding hypothesis was developed, which not only reproduces the observed experimental results but also predict the performance of a new gene circuit design. The aspirin-inducible systems were also functional in probiotic strainE.coliNissle 1917 (EcN) and SimCells produced fromE. coliMC1000 ΔminD. The well-characterised and modularised aspirin-inducible gene circuits would be useful biobricks for bacterial therapy in environment and medical applications.
Factor cooperation for chromosome discrimination in Drosophila
Authors: Albig Christian , Tikhonova Evgeniya , Krause Silke , Maksimenko Oksana , Regnard Catherine , Becker Peter B.
Published: September 2018

Transcription regulators select their genomic binding sites from a large pool of similar, non-functional sequences. Although general principles that allow such discrimination are known, the complexity of DNA elements often precludes a prediction of functional sites.

The process of dosage compensation in Drosophila allows exploring the rules underlying binding site selectivity. The male-specific-lethal (MSL) Dosage Compensation Complex selectively binds to some 300 X-chromosomal ‘High Affinity Sites’ (HAS) containing GA-rich ‘MSL recognition elements’ (MREs), but disregards thousands of other MRE sequences in the genome. The DNA-binding subunit MSL2 alone identifies a subset of MREs, but fails to recognize most MREs within HAS. The ‘Chromatin-linked adaptor for MSL proteins’ (CLAMP) also interacts with many MREs genome-wide and promotes DCC binding to HAS. Using genome-wide DNA-immunoprecipitation we describe extensive cooperativity between both factors, depending on the nature of the binding sites. These are explained by physical interaction between MSL2 and CLAMP. In vivo, both factors cooperate to compete with nucleosome formation at HAS. The male-specific MSL2 thus synergises with a ubiquitous GA-repeat binding protein for refined X/autosome discrimination.
Rayleigh-scattering microscopy for tracking and sizing nanoparticles in focused aerosol beams
Authors: Hantke Max F. , Bielecki Johan , Kulyk Olena , Westphal Daniel , Larsson Daniel S. D. , Svenda Martin , Reddy Hemanth K. N. , Kirian Richard A. , Andreasson Jakob , Hajdu Janos , Maia Filipe R. N. C.
Published: September 2018

Ultra-bright femtosecond X-ray pulses generated by X-ray free-electron lasers (XFELs) can be used to image high-resolution structures without the need for crystallization. For this approach, aerosol injection has been a successful method to deliver 70–2000 nm particles into the XFEL beam efficiently and at low noise. Improving the technique of aerosol sample delivery and extending it to single proteins necessitates quantitative aerosol diagnostics. Here a lab-based technique is introduced for Rayleigh-scattering microscopy allowing us to track and size aerosolized particles down to 40 nm in diameter as they exit the injector. This technique was used to characterize the `Uppsala injector', which is a pioneering and frequently used aerosol sample injector for XFEL single-particle imaging. The particle-beam focus, particle velocities, particle density and injection yield were measured at different operating conditions. It is also shown how high particle densities and good injection yields can be reached for large particles (100–500 nm). It is found that with decreasing particle size, particle densities and injection yields deteriorate, indicating the need for different injection strategies to extend XFEL imaging to smaller targets, such as single proteins. This work demonstrates the power of Rayleigh-scattering microscopy for studying focused aerosol beams quantitatively. It lays the foundation for lab-based injector development and online injection diagnostics for XFEL research. In the future, the technique may also find application in other fields that employ focused aerosol beams, such as mass spectrometry, particle deposition, fuel injection and three-dimensional printing techniques.
Numerical study of heat transfer performance in a pipe partially filled with non-uniform porous media under LTNE condition
Authors: Saberinejad Hojjat , Keshavarz Ali , Payandehdoost Mohammad , Azmoodeh Mohammad Reza , Batooei Alireza
Published: September 2018

Purpose

The purpose of this paper is to numerically investigate the heat transfer enhancement in a tube filled partially with porous media under non-uniform porosity distribution and thermal dispersion effects. The optimum porous thickness ratio [R_(r,Nu)] for the heat transfer enhancement under these conditions with and without considering required pumping power is evaluated.

Design/methodology/approach

The local thermal non-equilibrium and Darcy–Brinkman–Forchheimer models are used to simulated thermal and flow fields in porous region. The tube wall and flow regime are assumed to be isothermal and laminar, respectively. The impacts of Darcy number (Da = 10-6 - 10-1) and inertia parameter (F = 0 − 2) on the Nusselt number and friction factor are studied for non-uniform porosity distribution.

Findings

First, the effect of Nusselt number indicates that there are two different behaviors with respect to uniform and non-uniform porosity for partially and fully filled porous pipe. Second, variable porosity in porous region has significant influence on the optimum thickness ratio with considering required pumping power. For negligible inertia term, it depends on the Darcy number, whereas it is 0.9 at F > 1. Third, the plug flow assumption cannot be valid even at lower Darcy number under non-uniform porosity, while this assumption is applicable at Da < 10-3 for constant porosity distribution in porous region.

Originality/value

According to the best knowledge of authors, the optimum porous thickness ratio for the heat transfer enhancement considering the pressure loss effects under variable porosity has not reported up to now. Also the plug flow assumption in such physics is not discussed.
Interaction between precious metals price and Islamic stock markets
Authors: Tuna Gülfen
Published: September 2018

Purpose

This study aims to analyze the presence of a long-term relationship between precious metal prices, such as for gold, silver, platinum and palladium, and Islamic stock markets of 32 different countries – 21 developed and 11 developing. In this study, the long-term relationship between the precious metal prices and the Islamic stock markets of countries grouped by the Morgan Stanley Capital Index (MSCI) according to their level of development was examined. In the economies included in the study, it is necessary that the Islamic stock index be created by MSCI. It is not a constraint as a Muslim country.

Design/methodology/approach

This study used the Pedroni panel cointegration analysis and full modified ordinary least square method. All analyses in this study were performed using monthly data from 2002 to 2015.

Findings

According to the Pedroni panel cointegration analysis applied in this study, all four precious metals – gold, silver, platinum and palladium – are effective portfolio diversification tools for developed Islamic stock markets within the analyzed period. However, in developing countries, although gold and palladium are effective portfolio diversification tools, silver and platinum are not.

Practical implications

These results provide practical implications for academicians, practitioners as portfolio managers, policymakers. These implications are related in portfolio risk management, the diversification benefits and to propose new investment tools among developed and developing Islamic markets.

Social implications

This study is important for investors who assemble portfolios under the restriction of selecting investment tools suitable for Islamic rules. These investors are important in terms of using precious metals that they prefer as an alternative to stock markets to protect against the risks related to their suitable portfolio options. Governments, individuals and institutional investors that use capital stock according to Islamic rules in developed countries can effectively use gold, silver, platinum and palladium as hedging tools. However, this choice is limited to only gold and palladium in developing country markets. Gold continues to be an effective diversification tool in Islamic share markets, as in traditional stock markets.

Originality/value

The author would like to emphasize that this article is second to examine precious metals and Islamic stock markets in literature.
Towards a better understanding of fashion clothing purchase involvement
Authors: Rahman Mahfuzur , Albaity Mohamed , Isa Che Ruhana , Azma Nurul
Published: September 2018

Purpose

This study aims to concern with Malaysian consumer involvement in fashion clothing. To achieve this, materialism, fashion clothing involvement and religiosity are examined as drivers of fashion clothing purchase involvement.

Design/methodology/approach

Gender, race and age are explored to have better understanding of fashion clothing purchase involvement in Malaysia. Data were gathered using a Malaysian university student sample, resulting in 281 completed questionnaires.

Findings

The results support the study’s model and its hypotheses and indicate that materialism, fashion clothing involvement and religiosity are significant drivers of fashion clothing purchase involvement. Also, materialism is a significant driver of fashion clothing involvement, and fashion clothing involvement mediates the relationship between materialism and fashion clothing purchase involvement. The results also show that Malaysian youth do not possess a high level of materialistic tendencies.

Originality/value

This study offers enormous opportunities for the international apparel marketers to formulate relevant business policies and strategies.
A citation analysis of corporate social responsibility (1970-2014): insights from Islamic perspective
Authors: Alfakhri Yazeed , Nurunnabi Mohammad , Alfakhri Demah
Published: September 2018

Purpose

The purpose of this paper is to analyse the citations of scientific research on the concept of corporate social responsibility (CSR) from 1970 to 2014. In particular, several interconnected research questions were investigated: How did the conceptualisation of CSR change from 1970 to 2014? What is the general direction of the change? How does Islamic CSR emerge?

Design/methodology/approach

An in-depth analysis was performed with the use of the data analysis tool available in the Web of Science. The study categorises CSR into four areas: business ethics and corporate governance; management; marketing; and others. The first three categories were based on the Chartered Association of Business Schools’ Academic Journal Guide 2010 and 2015 (UK).

Findings

The findings reveal that 67.19 per cent articles have been published based on the ranked journals of Academic Journal Guide 2010 and 2015. The findings of the study will help to inform future areas of CSR. The top journals which published most articles from Academic Journal Guide 2015 areJournal of Business EthicsandCorporate Social Responsibility and Environmental Management.

Practical implications

The findings suggest that the remit of sustainability from Islamic perspective is wider. Islamic marketing, as an area, remains largely in need of empirical research. The business communities should successfully integrate Muslim communities into their marketing strategies.

Originality/value

To the best of the knowledge, this is the first study to explore citation analysis of general CSR literature and Islamic CSR. The study finds that there has been an increase in interest in this subject of CSR and Islam in the recent years. Future research is needed on theory and methodological analysis of general CSR field and Islamic CSR field.
Perception of the takaful operators’ performance towards customers’ intention in using medical takaful card among public sector
Authors: Haji Wahab Muhammad Zarunnaim
Published: September 2018

Purpose

This paper aims to examine the level and the relationship between the perception of the performance of takaful operators and the customers’ intention in using medical takaful card among public sectors in Kedah, Malaysia.

Design/methodology/approach

A quantitative research methodology was advocated to answer the objectives progressively. Data were collected from questionnaires and analyzed using SPSS v22. In total, 313 respondents were selected from three public sectors in Kedah, Malaysia.

Findings

The review found that the level of customers’ perception of performance towards the customers’ intention in using medical takaful card was high. Besides, the findings concluded that a positive moderate relationship was observed between the perception of the performance of takaful operators and the customers’ intention in using medical takaful card among public officers in Kedah, Malaysia.

Research limitations/implications

There were three major limitations of this paper. These limitations are further explained in the conclusion.

Practical implications

This study has provided some major implications. First, on behalf of the public sector institutions, the results of this study clearly showed that the intention of the public sector officers in using medical takaful card should be increased. Second, on behalf of the industry, this study could acknowledge them to improve their performance to increase efficiency, creativity and innovation to create a good impression among consumers. Third, the previous theory and literature related to the perception of performance is suitable to use even in the event that the takaful industry has been proven.

Originality/value

The paper is useful to takaful operators to provide a good perception of their performance in the process of influencing the customers, especially among the public sector officers, to enrol in the medical takaful coverage.
How perceptions of training impact employee performance
Authors: Guan Xiaoyu , Frenkel Stephen
Published: September 2018

Purpose

The purpose of this paper is to investigate the influence of firm training on the job performance of mainly semi-skilled manufacturing employees in the context of changes required to ensure the competitiveness of contemporary Chinese manufacturing.

Design/methodology/approach

Data were collected using a survey with time-lagged method and from multiple sources. The sample included 348 supervisor-subordinate dyads from two Chinese manufacturing firms. PROCESS macro tool (Hayes) was used to test the mediating role of work engagement and the moderating role of HRM strength in the training-performance relationship.

Findings

Work engagement mediates the relationship between training and in-role task performance, while the relationships between work engagement and both task performance and organizational citizenship behavior are moderated by HRM strength.

Research limitations/implications

Based on a time-lagged survey, causal relationships cannot be drawn from this study. Results point to future research on the training-performance relationship that more closely considers antecedents and the organizations’ internal and external contexts.

Practical implications

Managers should pay close attention to the context and process of training and learning from the employees’ perspective. In addition, a strong HRM system will improve the benefits of training on employee performance.

Originality/value

This study provides theoretical explanations on the mechanisms linking training and employee performance based on the ability-motivation-opportunity framework.
High-tech workplace tools are key to winning the war for talent
Authors: McNulty Jacob
Published: September 2018

Purpose

With HR now at the center of efforts to address the talent crisis, how can HR strategists best deploy their resources to help their organizations to rise to the challenge?

Design/methodology/approach

Data-driven digital solutions can be a good starting point for discovering what’s working with existing employees. A new breed of high-tech tools are giving HR departments the means to more thoroughly and actionably understand the factors that attract, retain and drive away quality employees.

Findings

Based on data from these tools, HR teams can design inviting, engaging and productive work environments.

Originality/value

The struggle to attract and retain quality talent in the workplace is real, it is escalating and it has landed right at the doorstep of HR departments. It is perhaps the most pressing priority they – and their entire organizations – must confront to keep pace in the ongoing US economic expansion.
Schooling, teachers in Jamaica and social responsibility: rethinking teacher preparation
Authors: Roofe Carmel
Published: September 2018

Purpose

In a context where standardized testing and achievement scores have become the hallmark of accountability frameworks, the issue of social responsibility is not given much attention in schools in Jamaica. This has led to a continuous decline of the moral and spiritual dimension of schooling in the country. This is evidenced through an increase in school violence and other disparities among students. This paper aims to explore teachers’ perception of how they are prepared for their role as agents of social responsibility.

Design/methodology/approach

Through interviews of 16 in-service teachers, this research sought to explore teachers’ perception of how they are prepared for their role as agents of social responsibility. Each participant in the study was interviewed using a structured interview schedule comprising six questions. Data collected were transcribed and analyzed by sorting and identifying codes. Pattern codes were established which were then interpreted to form themes. Three themes emerged which are used to present findings.

Findings

Findings revealed that teachers had a shared understanding of social responsibility; they felt that they were prepared for this role throughad hoccurriculum encounters, were not adequately prepared for their role and social responsibility required a belief in the idea first before it can be taught.

Research limitations/implications

The findings from the research are used to present arguments in the paper for emphasis on preparing student teachers to be agents of social responsibility and for a rethinking of teacher preparation curriculum in Jamaica. The paper also presents strategies that can be used to guide the re-thinking of teacher preparation programmes.

Practical implications

Teacher preparation programmes represent the avenue through which teachers can be prepared to develop their social consciousness, so that they can in turn help students. The results of this paper are means of helping teacher educators understand this.

Originality/value

This paper is one of the first since the early 1990s to discuss social responsibility as a key component of teacher preparation in Jamaica. It also fills the void of scarcity of research in Jamaica on teacher education on a whole and social responsibility in teacher education in particular.
The making of Chinese medicine in Hong Kong
Authors: Pang Ka Wei
Published: September 2018

Purpose

This paper aims to examine the development of Chinese medicine in Hong Kong and argues that Chinese medicine is not a mere healing practice but a discursive practice against its unique institutional context.

Design/methodology/approach

Reviewing the medical history in the colonial and post-colonial era, this paper delineates the dynamics between Chinese medicine and Western medicine, and the discursive shaping of Chinese medicine in Hong Kong.

Findings

While Chinese medicine in post-colonial Hong Kong is modernizing itself from a traditional medicine to the scientific Traditional Chinese medicine (TCM), it partakes in the decolonization and nationalization project and is geared towards the standardized TCM.

Originality/value

This paper proposed a critical cultural perspective in studying the discursive formation of Chinese medicine in Hong Kong.
Use of immune checkpoint inhibitors prolonged overall survival in a Japanese population of advanced malignant melanoma patients: Retrospective single institutional study
Authors: Nakamura Yoshiyuki , Fujisawa Yasuhiro , Tanaka Ryota , Maruyama Hiroshi , Ishitsuka Yosuke , Okiyama Naoko , Watanabe Rei , Fujimoto Manabu
Published: September 2018

Although recent clinical trials have revealed that immune checkpoint inhibitors significantly improved the overall survival (OS) of patients with advanced melanoma, these previous studies comprised mainly white populations, in which superficial spreading melanoma (SSM) and lentigo maligna melanoma are the major clinical types of melanoma. In contrast, Asians manifest a distinct clinicopathological type of melanoma from that of whites and show much higher frequencies of acral lentiginous melanoma (ALM) and mucosal melanoma, which have been shown to be less susceptible to immune checkpoint inhibitors. Because no comparative studies have been published showing improvement of OS by immune checkpoint inhibitors in Asian melanoma patients, we retrospectively collected the data for 45 melanoma patients treated with checkpoint inhibitors and 24 melanoma patients treated with chemotherapy alone before immune checkpoint inhibitors became available, and compared their OS. The results showed that the patients treated with immune checkpoint inhibitors had significantly better OS than did those treated with chemotherapy alone (P < 0.0001). Improved OS was observed in both the SSM and the ALM patients. In addition, multivariate Cox regression analyses revealed that use of immune checkpoint inhibitors was associated with favorable prognosis (P = 0.0001), indicating that use of immune checkpoint inhibitors is an independent factor for favorable survival. Our study showed that immune checkpoint inhibitors may also improve the prognosis of Asian melanoma patients.