bluuebunny/crossref_metadata_2025 huggingface dataset:
Variability in life-history switch points across and within populations explained by Adaptive Dynamics
Authors: Landi Pietro , Vonesh James R. , Hui Cang
Published: November 2018

Understanding the factors that shape the timing of life-history switch points (SPs; e.g. hatching, metamorphosis and maturation) is a fundamental question in evolutionary ecology. Previous studies examining this question from a fitness optimization perspective have advanced our understanding of why the timing of life-history transitions may vary across populations and environments. However, in nature we also often observe variability among individuals within populations. Optimization theory, which typically predicts a single optimal SP under physiological and environmental constraints for a given environment, cannot explain this variability. Here, we re-examine the evolution of a single life-history SP between juvenile and adult stages from an Adaptive Dynamics (AD) perspective, which explicitly considers the feedback between the dynamics of population and the evolution of life-history strategy. The AD model, although simple in structure, exhibits a diverse range of evolutionary scenarios depending upon demographic and environmental conditions, including the loss of the juvenile stage, a single optimal SP, alternative optimal SPs depending on the initial phenotype, and sympatric coexistence of two SP phenotypes under disruptive selection. Such predictions are consistent with previous optimization approaches in predicting life-history SP variability across environments and between populations, and in addition they also explain within-population variability by sympatric disruptive selection. Thus, our model can be used as a theoretical tool for understanding life-history variability across environments and, especially, within species in the same environment.
Experimental degradation of helicoidal photonic nanostructures in scarab beetles (Coleoptera: Scarabaeidae): implications for the identification of circularly polarizing cuticle in the fossil record
Authors: Odin Giliane P. , McNamara Maria E. , Arwin Hans , Järrendahl Kenneth
Published: November 2018

Scarab beetles (Coleoptera: Scarabaeidae) can exhibit striking colours produced by pigments and/or nanostructures. The latter include helicoidal (Bouligand) structures that can generate circularly polarized light. These have a cryptic evolutionary history in part because fossil examples are unknown. This suggests either a real biological signal, i.e. that Bouligand structures did not evolve until recently, or a taphonomic signal, i.e. that conditions during the fossilization process were not conducive to their preservation. We address this issue by experimentally degrading circularly polarizing cuticle of modern scarab beetles to test the relative roles of decay, maturation and taxonomy in controlling preservation. The results reveal that Bouligand structures have the potential to survive fossilization, but preservation is controlled by taxonomy and the diagenetic history of specimens. Further, cuticle of specific genus (Chrysina) is particularly decay-prone in alkaline conditions; this may relate to the presence of certain compounds, e.g. uric acid, in the cuticle of these taxa.
Pillar versus dimple patterned surfaces for wettability and adhesion with varying scales
Authors: Li Meng , Dai Qingwen , Huang Wei , Wang Xiaolei
Published: November 2018

Inspired by biological topographical surfaces, micropatterned elastomeric surfaces with square pillars and dimples of different geometry scales were fabricated. Their wettability and adhesion properties with various liquids were systematically investigated and compared with flat surfaces. Interesting results were obtained in the case of silicone oil (the toe-pad-like wetting case) in that the scale-dependent wettability and adhesion performed inversely for pillars and dimples. Micropillars significantly enhanced the surface wettability with a geometry scale dependence, whereas the dimples suppressed the wettability independent of the geometry scale. The adhesion force of the micropillars increased with an increase of the geometry scale. However, in the case of the micro-dimples, the adhesion force obviously decreased with an increase of the geometry scale. This behaviour was attributed to the fact that pillars are ‘open’ to oil but dimples are ‘close’ to oil, presenting different orientations to the solid–liquid interface.
Study of complex impedance spectroscopic properties of La

0.7−
x

Dy

x

Sr
0.3
MnO
3
perovskite oxides
Authors: Debbebi I. Sfifir , Megdiche-Borchani S. , Cheikhrouhou-Koubaa W. , Cheikhrouhou A.
Published: November 2018

The dysprosium perovskite La

0.7−
x

Dy

x

Sr
0.3
MnO
3
(
x
= 0.00 [LSMO] and 0.03 [LDSMO]) compounds were prepared by the sol–gel reaction and characterized by the X-ray diffraction technique. The electrical conductivity and modulus characteristics of the system have been investigated in the temperature and the frequency range 311–356 K and 209–5 × 10
7
Hz, respectively, by means of impedance spectroscopy. The ac and dc conductivities were studied to explore the mechanisms of conduction of LSMO and LDSMO. The insertion of a small amount of Dy
3+
in the La-site of LSMO perovskite oxide increases the value of the activation energy from 0.2106 to 0.5357 eV and enhances electrical resistivity values for almost two orders of magnitude.
Microbial oil production from solid-state fermentation by a newly isolated oleaginous fungus,
Mucor circinelloides
Q531 from mulberry branches
Authors: Qiao Weichuan , Tao Junqi , Luo Yang , Tang Tianhao , Miao Jiahui , Yang Qiwen
Published: November 2018

In this study, a newly isolated oleaginous fungus,
Mucor circinelloides
(
M. circinelloides
) Q531, was able to convert mulberry branches into lipids. The highest yield and the maximum lipid content produced by the fungal cells were 42.43 ± 4.01 mg per gram dry substrate (gds) and 28.8 ± 2.85%, respectively. The main components of lignocellulosic biomass were gradually reduced during solid-state fermentation (SSF). Cellulose, hemicellulose and lignin were decreased from 45.11, 31.39 and 17.36% to 41.48, 28.71, and 15.1%, respectively. Gas chromatography analysis showed that the major compositions of the fermented products were palmitic acid (C16:0, 18.42%), palmitoleic acid (C16:1, 5.56%), stearic acid (C18:0, 5.87%), oleic acid (C18:1, 33.89%), linoleic acid (C18:2, 14.45%) and γ-linolenic acid (C18:3 n6, 22.53%) after 2 days of SSF. The fatty acid methyl esters contained unsaturated fatty acids with a ratio of 75.95%. The composition and content obtained in this study are more advantageous than those of many other biomass lipids. Meanwhile, the oleaginous fungus had a high cellulase activity of 1.39 ± 0.09 FPU gds
−1
. The results indicate that the enzyme activity of the isolated fungus was capable of converting the cellulose and hemicelluloses to available sugar monomers which are beneficial for the production of lipids.
Mutations in bacterial genes induce unanticipated changes in the relationship between bacterial pathogens in experimental otitis media
Authors: Lakhani Vinal , Tan Li , Mukherjee Sayak , Stewart William C. L. , Swords W. Edward , Das Jayajit
Published: November 2018

Otitis media (OM) is a common polymicrobial infection of the middle ear in children under the age of 15 years. A widely used experimental strategy to analyse roles of specific phenotypes of bacterial pathogens of OM is to study changes in co-infection kinetics of bacterial populations in animal models when a wild-type bacterial strain is replaced by a specific isogenic mutant strain in the co-inoculating mixtures. As relationships between the OM bacterial pathogens within the host are regulated by many interlinked processes, connecting the changes in the co-infection kinetics to a bacterial phenotype can be challenging. We investigated middle ear co-infections in adult chinchillas (
Chinchilla lanigera
) by two major OM pathogens: non-typeable
Haemophilus influenzae
(NTHi) and
Moraxella catarrhalis
(Mcat), as well as isogenic mutant strains in each bacterial species. We analysed the infection kinetic data using Lotka–Volterra population dynamics, maximum entropy inference and Akaike information criteria-(AIC)-based model selection. We found that changes in relationships between the bacterial pathogens that were not anticipated in the design of the co-infection experiments involving mutant strains are common and were strong regulators of the co-infecting bacterial populations. The framework developed here allows for a systematic analysis of host–host variations of bacterial populations and small sizes of animal cohorts in co-infection experiments to quantify the role of specific mutant strains in changing the infection kinetics. Our combined approach can be used to analyse the functional footprint of mutant strains in regulating co-infection kinetics in models of experimental OM and other polymicrobial diseases.
Improving short-term information spreading efficiency in scale-free networks by specifying top large-degree vertices as the initial spreaders
Authors: Wang Shuangyan , Deng Yunfeng , Li Ying
Published: November 2018

The positive function of initially influential vertices could be exploited to improve spreading efficiency for short-term spreading in scale-free networks. However, the selection of initial spreaders depends on the specific scenes. The selection of initial spreaders needs to offer low complexity and low power consumption for short-term spreading. In this paper, we propose a selection strategy for efficiently spreading information by specifying a set of top large-degree vertices as the initially informed vertices. The essential idea behind the proposed selection strategy is to exploit the significant diffusion of the top large-degree vertices at the beginning of spreading. To evaluate the positive impact of initially influential vertices, we first build an information spreading model in the Barabási–Albert (BA) scale-free network; next, we design 54 comparative Monte Carlo experiments based on a benchmark strategy and the proposed selection strategy in different BA scale-free network structures. Experimental results indicate that (i) the proposed selection strategy can significantly improve spreading efficiency in the short-term spreading and (ii) both network size and number of hubs have a strong impact on spreading efficiency, while the number of initially informed vertices has a weak impact. The proposed selection strategy can be employed in short-term spreading, such as sending warnings or crisis information spreading or information spreading in emergency training or realistic emergency scenes.
Enhancing hydrophobicity, strength and UV shielding capacity of starch film via novel co-cross-linking in neutral conditions
Authors: Shuzhen Ni , Liang Jiao , Hui Zhang , Yongchao Zhang , Guigan Fang , Huining Xiao , Hongqi Dai
Published: November 2018

Starch films are developed as the biodegradable packaging materials to replace the petroleum-based materials in recent years. Thus, it is extremely beneficial to improve the hydrophobicity and mechanical strength of starch films, through a novel approach of co-cross-linking in neutral conditions, with glyoxal and AZC. In this work, systematic studies have been conducted to assess the performance of the co-cross-linked starch along with the control starch and starch cross-linked by glyoxal or AZC alone. Results showed that the co-cross-linked starch films exhibited significantly improved hydrophobicity and strength and the wet stress reached 1.53 MPa, compared to the control, glyoxal or AZC cross-linked starch films. More interestingly, the co-cross-linked film also demonstrated excellent UV shielding capacity and transmittance at visible wavelength range. The reaction mechanism was revealed based on the findings from UV, FT-IR and NMR spectra. This work established an innovative approach to improving the performance of starch film in neutral conditions for packaging applications.
Total synthesis of [
15
N]-labelled C6-substituted purines from [
15
N]-formamide—easy preparation of isotopically labelled cytokinins and derivatives
Authors: Buček Jan , Zatloukal Marek , Havlíček Libor , Plíhalová Lucie , Pospíšil Tomáš , Novák Ondřej , Doležal Karel , Strnad Miroslav
Published: November 2018

Cytokinins (CKs) and their metabolites and derivatives are essential for cell division, plant growth regulation and development. They are typically found at minute concentrations in plant tissues containing very complicated biological matrices. Therefore, defined standards labelled with stable isotopes are required for precise metabolic profiling and quantification of CKs, as well as
in vivo
elucidation of CK biosynthesis in various plant species. In this work, 11 [
15
N]-labelled C6-purine derivatives were prepared, among them 5 aromatic (
4, 5, 6, 7, 8
) and 3 isoprenoid (
9, 10, 11
) CKs. Compared to current methods, optimized syntheses of 6-amino-9H-[
15
N
5
]-purine (adenine) and 6-chloro-9H-[
15
N
4
]-purine (6-chloropurine) were performed to achieve more effective, selective and generally easier approaches. The chemical identity and purity of prepared compounds were confirmed by physico-chemical analyses (TLC; HRMS; HPLC–MS;
1
H,
13
C,
15
N NMR). The presented approach is applicable for the synthesis of any other desired [
15
N
4
]-labelled C6-substituted purine derivatives.
Culling less fit neurons protects against amyloid-β-induced brain damage and cognitive and motor decline
Authors: Coelho Dina S. , Schwartz Silvia , Merino Marisa M. , Hauert Barbara , Topfel Barbara , Tieche Colin , Rhiner Christa , Moreno Eduardo
Published: November 2018

Alzheimer’s disease (AD) is the most common form of dementia, impairing cognitive and motor functions. One of the pathological hallmarks of AD is neuronal loss, which is not reflected in mouse models of AD. Therefore, the role of neuronal death is still uncertain. Here, we used aDrosophilaAD model expressing a secreted form of human amyloid-β42 peptide and show that it recapitulates key aspects of AD pathology, including neuronal death and impaired long-term memory. We found that neuronal apoptosis is mediated by cell fitness-driven neuronal culling, which selectively eliminates impaired neurons from brain circuits. We show that removal of less fit neurons delays amyloid-β42-induced brain damage and protects against cognitive and motor decline, suggesting that - contrary to common knowledge - neuronal death may have a beneficial effect in AD.
ABC-transporter activity and autocrine eicosanoid-signaling are required for germ cell migration a basal chordate
Authors: Kassmer Susannah H. , Rodriguez Delany , DeTomaso Anthony
Published: November 2018

In the colonial ascidianBotryllus schlosseri, long-lived germline stem cells (GSCs) migrate to new germline niches as they develop during repetitive cycles of asexual reproduction. ABC-transporters are involved in the export of lipid-signaling molecules, but their roles in germ cell migration are poorly understood. Here, we show that inBotryllus, abcc1andabcb1are highly expressed in germ cells, and inhibition of ABC-transporter activity leads to failure of germ cell migration. Phospholipase A2 (PLA2) produces arachidonic acid, which is further metabolized to eicosanoid signaling molecules. In humans, 12-lipoxygenase (LOX) metabolizes arachidonic acid to12-Hydroxyeicosatetraenoic acid (12-S-HETE), which stimulates migration of mammalian cancer cells and smooth muscle cells. We show that PLA2 and LOX activity are required for germ cell migration. A potential homolog to the human receptor for 12-S-HETE,BSgpr31, is expressed in germ cells. 12-S-HETE rescues migration towards S1P in the presence of inhibitors of ABCC1, ABCB1, PLA2 or LOX, and a gradient of 12-S-HETE enhances chemotaxis towards S1P and stimulates motility. We conclude that 12-S-HETE is a secondary chemoattractant exported by ACB-transporters that is required for migration of germ cells towards S1P. We also find that in the presence of S1P, detection of an 12-S-HETE gradient initiates an autologous positive feedback loop that may sustain migration. This is the first report of an eicosanoid-signaling molecule regulating germ cell migration.
HPV detection and genotyping of FFPE head and neck cancer biopsies by molecular testing to address new oropharyngeal squamous cell carcinoma classification based on HPV status
Authors: Veyer David , Wack Maxime , Grard Ophélie , Bonfils Pierre , Hans Stéphane , Belec Laurent , Badoual Cécile , Péré Hélène
Published: November 2018

Recently, both the WHO/IARC (World Health Organisation/International Agency for Research on Cancer) and the American Joint Committee on Cancer (AJCC) have classified the oropharyngeal squamous cell carcinoma (OPSCC) on the basis of HPV status. For this purpose, the WHO/IARC recommended direct molecular HPV testing. In practice, formalin-fixed, paraffin-embedded (FFPE) biopsy specimens are frequently the only available samples. We herein compared in parallel two commercially available molecular assays that were firstly designed for cervical HPV detection and genotyping: Inno-Lipa® HPV genotyping extra II assay (Fujirebio, Gent, Belgium) (IL) and AnyplexTM II HPV 28 (Seegene, Seoul, South Korea) (AP28).

Both assays were carried out on the same DNA extracts obtained from prospectively collected FFPE biopsies from OPSCC origin and results were compared.

A total of 55 samples were tested. By IL assay, chosen as reference assay, 27 (49.1%) biopsies were positive for HPV16, 10 (18.2%) were positive for HPV but negative for HPV16, and 18 (32.7%) were negative for HPV. A valid result with AP28 was obtained for 51 biopsy samples (92.7%). Among 37 HPV-positive samples by IL, 33 (89.2%) were positive by AP28. The agreement between both assays was good (Cohen’s κ = 0.78). Among the six discrepancies between assays, always associated with low HPV16 viral load, four biopsies positive for HPV16 by IL could not be detected by AP28.

Taken together, these observations demonstrate that both assays could be used in routine for HPV detection and genotyping on FFPE-biopsy samples of head and neck tumour.
“I hear with my little ear something…": Enhanced performance of absolute pitch musicians in an interleaved melody recognition test
Authors: Wenhart Teresa , Hwang Ye-Young , Altenmüller Eckart
Published: November 2018

Autistic people exhibit enhanced abilities to find and extract visual or auditory figures out of a meaningful whole (disembedding). Studies have shown heightened autistic traits in professional musicians with absolute pitch (AP). This study investigates whether such musicians show an advantage in an interleaved melody recognition task (IMRT).

A total of N=59 professional musicians (AP=27) participated in the study. In each trial a probe melody was followed by an interleaved sequence. Subjects had to indicate as to whether the probe melody was present in the interleaved sequence. Sensitivity index d’ and response bias c were calculated according to signal detection theory. Additionally, a pitch adjustment test measuring fine-graded differences in absolute pitch proficiency, the Autism-Spectrum-Quotient and a visual embedded figures test were conducted.

AP performance was enhanced overall compared to RP. Absolute pitch proficiency, visual disembedding ability and musicality predicted approximately 39.2% of variance in the interleaved melody recognition test. No correlations were found between IMRT and autistic traits.

The stable pitch-label associations of AP might serve as additional sensory cues during pre-attentive processing in recognizing interleaved melodies. Results are in line with a detailed-oriented cognitive style and enhanced perceptional functioning of AP musicians similar to that observed in autism.
Precisely control mitochondria with light to manipulate cell fate decision
Authors: Ernst Patrick , Xu Ningning , Qu Jing , Chen Herbert , Goldberg Matthew S. , Darley-Usmar Victor , Zhang Jianyi J. , O’Rourke Brian , Liu Xiaoguang , Zhou Lufang
Published: November 2018

Mitochondrial dysfunction has been implicated in many pathological conditions and diseases. The normal functioning of mitochondria relies on maintaining the inner mitochondrial membrane (IMM) potential (a.k.a.ΔΨm) that is essential for ATP synthesis, Ca2+homeostasis, redox balance and regulation of other key signaling pathways such as mitophagy and apoptosis. However, the detailed mechanisms by which ΔΨmregulates cellular function remain incompletely understood, partially due to difficulty of manipulating ΔΨmwith spatiotemporal resolution, reversibility, or cell type specificity. To address this need, we have developed a next-generation optogenetic-based technique for controllable mitochondrial depolarization with light. We demonstrate successful targeting of the heterologous Channelrhodopsin-2 (ChR2) fusion protein to the IMM and formation of functional cationic channels capable of light-induced selective ΔΨmdepolarization and mitochondrial autophagy. Importantly, we for the first time show that optogenetic-mediated mitochondrial depolarization can be well-controlled to differentially influence the fate of cells expressing mitochondrial ChR2: while sustained moderate light illumination induces substantial apoptotic cell death, transient mild light illumination elicits cytoprotectionviamitochondrial preconditioning. Finally, we show that Parkin overexpression exacerbates, instead of ameliorating, mitochondrial depolarization-mediated cell death in HeLa cells. In summary, we provide evidence that the described mitochondrial-targeted optogenetics may have a broad application for studying the role of mitochondria in regulating cell function and fate decision.
High-throughput interrogation of programmed ribosomal frameshifting in human cells
Authors: Mikl Martin , Pilpel Yitzhak , Segal Eran
Published: November 2018

Programmed ribosomal frameshifting is the controlled slippage of the translating ribosome to an alternative frame. This tightly regulated process is widely employed by human viruses such as HIV and SARS coronavirus and is critical for their life cycle and virulence. It is also utilized from yeast to human to implement a feedback control mechanism to regulate polyamine levels. Here, we developed a high-throughput, fluorescence-based approach to assess the frameshifting potential of a sequence. We designed and tested >12,000 sequences based on 15 viral and human frameshifting events, allowing us to elucidate the rules governing ribosomal frameshifting in a systematic way and to discover novel regulatory inputs based on amino acid properties and tRNA availability. We assessed the natural variation in HIV gag-pol frameshifting rates by testing >500 clinical isolates and identified subtype-specific differences as well as associations between viral load in patients and the optimality of gag-pol frameshifting rates. We further devised computational models that accurately predict frameshifting potential (up to auROC=0.93) and frameshifting rates (up to Pearson r=0.81) of novel variants, including subtle differences between HIV clinical isolates (r=0.60). Taken together, this systematic approach can contribute to the development of antiviral agents acting on programmed ribosomal frameshifting.
Chromatin Compaction by Small RNAs and the Nuclear RNAi Machinery inC. elegans
Authors: Fields Brandon D. , Kennedy Scott
Published: November 2018

DNA is organized and compacted into higher-order structures in order to fit within nuclei and to facilitate proper gene regulation. Mechanisms by which higher order chromatin structures are established and maintained are poorly understood. InC. elegans, nuclear-localized small RNAs engage the nuclear RNAi machinery to regulate gene expression and direct the post-translational modification of histone proteins. Here we confirm a recent report suggesting that nuclear small RNAs are required to initiate or maintain chromatin compaction states inC. elegansgerm cells. Additionally, we show that experimentally provided small RNAs are sufficient to direct chromatin compaction and that this compaction requires the small RNA-binding Argonaute NRDE-3, the pre-mRNA associated factor NRDE-2, and the HP1-like protein HPL-2. Our results show that small RNAs, acting via the nuclear RNAi machinery and an HP1-like protein, are capable of driving chromatin compaction inC. elegans.
The structural basis for release factor activation during translation termination revealed by time-resolved cryogenic electron microscopy
Authors: Fu Ziao , Indrisiunaite Gabriele , Kaledhonkar Sandip , Shah Binita , Sun Ming , Chen Bo , Grassucci Robert A. , Ehrenberg Måns , Frank Joachim
Published: November 2018

When the mRNA translating ribosome encounters a stop codon in its aminoacyl site (A site), it recruits a class-1 release factor (RF) to induce hydrolysis of the ester bond between peptide chain and peptidyl-site (P-site) tRNA. This process, called termination of translation, is under strong selection pressure for high speed and accuracy. Class-1 RFs (RF1, RF2 in bacteria, eRF1 in eukarya and aRF1 in archaea), have structural motifs that recognize stop codons in the decoding center (DC) and a universal GGQ motif for induction of ester bond hydrolysis in the peptidyl transfer center (PTC) 70 Å away from the DC. The finding that free RF2 is compact with only 20 Å between its codon reading and GGQ motifs came therefore as a surprise1. Cryo-electron microscopy (cryo-EM) then showed that ribosome-bound RF1 and RF2 have extended structures2,3, suggesting that bacterial RFs are compact when entering the ribosome and switch to the extended form in a stop signal-dependent manner3. FRET4, cryo-EM5,6 and X-ray crystallography7, along with a rapid kinetics study suggesting a pre-termination conformational change on the millisecond time-scale of ribosome-bound RF1 and RF28, have lent indirect support to this proposal. However, direct experimental evidence for such a short-lived compact conformation on the native pathway to RF-dependent termination is missing due to its transient nature. Here we use time-resolved cryo-EM9,10,11,12,13 to visualize compact and extended forms of RF1 and RF2 at 3.5 and 4 Å resolution, respectively, in the codon-recognizing complex on the pathway to termination. About 25% of ribosomal complexes have RFs in the compact state at 24 ms reaction time after mixing RF and ribosomes, and within 60 ms virtually all ribosome-bound RFs are transformed to their extended forms.
The landscape of DNA methylation associated with the transcriptomic network in laying hens and broilers generates insight into embryonic muscle development in chicken
Authors: Liu Zihao , Shen Xiaoxu , Han Shunshun , Wang Yan , Zhu Qing , Cui Can , He Haorong , Zhao Jing , Chen Yuqi , Zhang Yao , Ye Lin , Zhang Zhichao , Li Diyan , Zhao Xiaoling , Yin Huadong
Published: November 2018

As DNA methylation is one of the key epigenetic mechanisms involved in embryonic development, elucidating its relationship with non-coding RNA and genes is essential for understanding early development. In this study, we performed single-base-resolution bisulfite sequencing together with RNA-seq to explore the genetic basis of embryonic muscle development in chicken. Comparison of methylome profiles between broilers and laying hens revealed that lower methylation in broilers might contribute to muscle development. Differential methylated region (DMR) analysis between two chicken lines showed that the majority of DMRs were hypo-DMRs for broilers. Differential methylated genes were significantly enriched in muscle development-related terms at E13 and E19. Furthermore, by constructing the network of the lncRNAs, we identified a lncRNA, which we named MYH1-AS, that potentially regulated muscle development. These findings reveal an integrative landscape of late period of embryonic myogenesis in chicken and give rise to a comprehensive understanding of epigenetic and transcriptional regulation, in skeletal muscle development. Our study provides a reliable data resource for further muscle studies.
On a Unifying ‘Reverse’ Regression for Robust Association Studies and Allele Frequency Estimation with Related Individuals
Authors: Zhang Lin , Sun Lei
Published: November 2018

For genetic association studies with related individuals, standard linear mixed-effect model is the most popular approach. The model treats a complex trait (phenotype) as the response variable while a genetic variant (genotype) as a covariate. An alternative approach is to reverse the roles of phenotype and genotype. This class of tests includes quasi-likelihood based score tests. In this work, after reviewing these existing methods, we propose a general, unifying ‘reverse’ regression framework. We then show that the proposed method can also explicitly adjust for potential departure from Hardy–Weinberg equilibrium. Lastly, we demonstrate the additional flexibility of the proposed model on allele frequency estimation, as well as its connection with earlier work of best linear unbiased allele-frequency estimator. We conclude the paper with supporting evidence from simulation and application studies.
Business case for diversification – Adult Basic Education society (ABES), Pakistan
Authors: Dogar Muhammad Nadeem
Published: November 2018

Supplementary materials

I would recommend the following two readings: Kotter, J. P. 2001. “What leaders really do” Harvard Business Review, vol, December 2001, pp. 85-96 and MIntzberg, H. & Waters, J. A. 1985. “Of strategies, deliberate and emergent” Strategic Management Journal, Vol. 6, pp. 257-272 Teaching Notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

Learning outcomes

This case study aims to provide following four learning outcomes: enhanced understanding of organizational leadership style/approach in terms of rigidness or flexibility to bring modifications in organizational vision to tap current opportunities, enhanced understanding of the use of emotions and rationality in organizational decision-making to strike a balance between organizational needs and community needs in the context of organizational priority framework, enhanced understanding of issue of integration to meet community needs smartly particularly in social development organizations and enhanced understanding of leadership strategies for successful business diversification.

Case overview/synopsis

This case study highlights and discusses three issues: first, it explores issues related to change in organizational vision and aims keeping in mind the needs of community rather than sticking to organizational needs (flexibility versus rigidity). Second, it explores the role of emotions and rationality in organizational decision-making by its leadership. Third, it discusses the role of leadership in successfully transforming one-dimensional organization into multidimensional organization by adding new avenues for future growth by mobilizing existing organizational strengths and competencies. Finally, this case discusses theories of leadership and change management in the context of social development organizations to align their activities with community’s emerging needs.

Complexity academic level

Master Level - Master of Business Administration and Master of Management. This case provides sufficient material to be discussed at master level courses such as change leadership and change management in social development organizations.

Supplementary materials

Teaching Notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

Subject code

Management science
What’s in a name? Family violence involving older adults
Authors: Benbow Susan M. , Bhattacharyya Sharmi , Kingston Paul
Published: November 2018

Purpose

The purpose of this paper is to review the terminology used to describe family violence involving older adults in order to stimulate a discussion that may assist in the use of a more appropriate and clearer terminology.

Design/methodology/approach

Different definitions of terms used to describe violence are considered and the contexts in which they are used. Two cases are described to illustrate the use of overlapping terms, the assumptions that lie behind them and the different actions that they lead to.

Findings

The authors argue that legal, relational, health (physical and mental) and social perspectives are all useful and integration contributes to a fuller understanding of violence.

Originality/value

The importance of terminology used to describe family violence involving older adults has been neglected in the past, yet it influences understanding about violent incidents and shapes responses to them.
Sukukrisks – a structured review of theoretical research
Authors: Hasan Rashedul , Ahmad Abu Umar Faruq , Parveen Tamiza
Published: November 2018

Purpose

The key purpose of this study is to make awareness for faithful Muslims who are interested to invest in Islamic capital markets so as to enable them making right decision while considering investment inSukukover conventional interest-bearing bonds.

Design/methodology/approach

This study reviews past literature to analyse contemporarySukukrisks and discusses several mechanisms to mitigate those risks.

Findings

The study shows thatSukukcan be good alternatives to conventional bonds.Sukukstructures need to be further developed to fulfil theSharīʿahcompliance requirements.

Research limitations/implications

This study is exploratory in nature, and as such, it seeks to identify the risks related toSukukissuance. Given this limitation, it did not provide empirical evidences relating to any specific category ofSukukrisks.

Practical implications

An in-depth knowledge ofSukukrisks would help both academicians and investors understand the potential problems related toSukukstructures and take precautions in the early stage to prevent causes of being defaulted or bankrupt.

Originality/value

The risks related toSukukhave been explored in all potential roots. This study has offered some significant techniques to prevent the relevant risks for investors’ benefits. Information being provided throughout this study is expected to serve potential investors inSukukas a guide to make right decisions and enable them to minimise the risk to secure healthy returns on their investments.
Accountability in Islamic financial institution
Authors: Aribi Zakaria Ali , Arun Thankom , Gao Simon
Published: November 2018

Purpose

The purpose of this paper is to explore whether any discrepancy exists between the disclosed in SSB reports of Islamic banks and the disclosure index which was based on stakeholders’ expectation.

Design/methodology/approach

This study uses contents analysis as the research method to explore Shariâ’ah audit reporting practices of Islamic Banks.

Findings

The study finds that the level of disclosures overall by IFIs in the sample is rather low compared to the stakeholder expectations.

Practical implications

This paper has important implication for policy makers as it contribute to the debate on that uniform disclosure standards across the globe need to be implemented to ensure a uniform level of disclosure by Islamic banks.

Originality/value

This study is amongst the few studies that examine and explore the nature and extent ofShari’ahSupervisory Board in Islamic banks.
The influence of culture on service quality leading to customer satisfaction and moderation role of type of bank
Authors: Endara Yousef Mohamed , Ali Asbi B. , Yajid Mohd Shukri Ab
Published: November 2018

Purpose

Considering the importance of current Libyan business environment, this paper aims to understand the influence of culture on perceived service quality that leads to customer satisfaction in the Libyan banking industry. In addition, it would be interesting to explore which type of banks, e.g. public or private banks, moderate the relationship between perceived service quality and customer satisfaction.

Design/methodology/approach

The data were collected from the customers who are receiving services from the top three private and top three public banks in the cities of Tripoli and Misurata, Libya. About 329 samples were obtained and Smart PLS was used for the statistical analysis.

Findings

The results show that perceived service quality is strongly predicted by collectivism, masculinity and uncertainty avoidance. Perceived service quality also leads to customer satisfaction among the Libyan banking customers. Further, public bank is more concerned on customer satisfaction compared to private banks.

Practical implication

The research has greater implication for the Middle-Eastern bank managers who are pursuing possibilities of newer business strategies.

Originality

The study provides an interesting viewpoint of the banking service in Libya, especially in the economic uncertainty post-war and political instability. Its focus on culture as a strong influence to the delivery of service quality in such context is admirable especially in relation with the embedded Islamic culture.
Does salience matter in investment decision?
Authors: Chaudary Samra
Published: November 2018

Purpose

The paper takes a behavioral approach by making use of the prospect theory to unveil the impact of salience on short-term and long-term investment decisions. This paper aims to investigate the group differences for two types of investors’ groups, i.e. individual investors and professional investors.

Design/methodology/approach

The study uses partial least square-based structural equation modeling technique, measurement invariance test and multigroup analysis test on a unique data set of 277 active equity traders which included professional money managers and individual investors.

Findings

Results showed that salience has a significant positive impact on both short-term and long-term investment decisions. The impact was almost 1.5 times higher for long-term investment decision as compared to short-term decision. Furthermore, multigroup analysis revealed that the two groups (individual investors and professional investors) were statistically significantly different from each other.

Research limitations/implications

The study has implications for financial regulators, money managers and individual investors as it was found that individual investors suffer more with salience heuristic and may end up with sub-optimal portfolios due to inefficient diversification. Thus, investors should be cautious in fully relying on salience and avoid such bias to improve investment returns.

Practical implications

The study concludes with a discussion of policy and regulatory implications on how to minimize salience bias to achieve optimum and diversified portfolios.

Originality/value

The study has significantly contributed to the growing body of applied behavioral research in the discipline of finance.
Rare and phylogenetically distinct plant species exhibit less diverse root‐associated pathogen communities
Authors: Chen Yongjian , Jia Pu , Cadotte Marc William , Wang Pandeng , Liu Xiang , Qi Yanling , Jiang Xiaomin , Wang Zihui , Shu Wensheng
Published: November 2018

One of the central questions in ecology is why some species are abundant while others are rare. In plant communities, some studies show that rare plant species are rare because they suffer stronger negative density‐dependent effects from pathogens compared to abundant plant species. Moreover, such pathogen effects are also suggested to be related to phylogenetic distance among plant species. However, the importance of pathogens has been commonly inferred by treating the entire pathogen community as a “black box” without explicitly characterizing pathogen richness and community composition.

Here, we test two predictions. First, if rare plant species are more susceptible to pathogens, we predict that rare plant species are associated with a higher richness of specialists (i.e., pathogens that attack only a single plant species) and/or the total pathogen community. If phylogenetically distinct plant species are less susceptible to pathogens, we predict that plant species with higher phylogenetic distinctiveness (i.e., a measure of how phylogenetically distant a species is from other co‐occurring species) are associated with a lower richness of phylogenetic specialists (i.e., pathogens that attack closely related plant species) and/or the total pathogen community.

We conducted a survey of the root‐associated pathogen communities from 45 plant species in a subtropical forest. We showed that approximately 40% and 25% of the pathogens were specialists and phylogenetic specialists respectively. In contrast to our first prediction, the richness of the total pathogen community but not the richness of the specialists was found to be positively related to plant species abundance, indicating that rare plant species suffer less from pathogens. Consistent with our second prediction, both the richness of the phylogenetic specialists and the total pathogen community were found to be negatively related to plant species phylogenetic distinctiveness. Furthermore, these correlations were stronger at the earlier plant life stages examined.

Synthesis. We found that the root‐associated pathogen communities were less diverse in rare plant species and plant species with few close relatives. These associations varied across multiple plant life stages, suggesting that the strength of the above‐ground–below‐ground interactions change dynamically across plant life span.
Negative effects of vertebrate on invertebrate herbivores mediated by enhanced plant nitrogen content
Authors: Zhu Yu , Zhong Zhiwei , Pagès Jordi F. , Finke Deborah , Wang Deli , Ma Quanhui , Hassan Nazim , Zhu Hui , Wang Ling
Published: November 2018

Classic theory holds that the main interaction within the herbivore guild is competition, based on research focused on co‐occurring, similarly sized species that reduce the quantity of shared plant resources. However, plant quality may also be crucial in mediating herbivore interspecific interactions. This is especially true when competition occurs between distantly related herbivore species, given that small terrestrial herbivores (e.g., insect herbivores) appear to be more sensitive to alterations of plant quality than plant quantity.

In this study, we first tested in the field whether large vertebrate herbivores (cattle Bos taurus) exerted a negative effect on smaller insect herbivores (grasshopper Euchorthippus unicolor) through their overlapping foraging preferences for a dominant grass Leymus chinensis. We measured changes in grass quantity, grass quality, and microclimatic conditions in response to vertebrate grazing and conducted additional manipulative studies in the field and the laboratory to identify potential mechanisms underlying the interaction.

Our results showed that grazing by large herbivores caused a significant decline in grasshopper population density and individual performance (survival, size, and weight of both female and male E. unicolor), despite a 38% increase in grass nitrogen (N) content in grazed plots. Experiments manipulating N levels of L. chinensis in the field and the laboratory confirmed that enriching plant N had a negative effect on grasshopper individual performance and population size. Therefore, enhanced quality (N content) of plant resources appears to be an important driver in mediating the negative effect of vertebrate grazing on grasshoppers.

Synthesis. We document that phylogenetic relatedness and trait similarity can be poor predictors of interaction strength in some cases, since distantly related herbivores of disparate size can interact indirectly via changes in plant quality. Counter‐intuitively, the observed negative effect of cattle on grasshoppers was mediated, at least in part, by an increase in plant quality in cattle grazed areas. The implication is that light to moderate grazing, a common management strategy, may contribute to suppression of grasshoppers in the Eurasian steppe grassland system by altering plant nutrient supplies.
Eating and drinking with an inflated tracheostomy cuff: a systematic review of the aspiration risk*
Authors: Goff Diane , Patterson Joanne
Published: November 2018

Background

Speech and language therapists (SLT) lack consensus with regard to assessing the swallow function of a patient with a cuff‐inflated tracheostomy. In the UK, one‐third would not accept such a referral due to perceived negative effects on swallow safety. Patients may be spending longer hospitalized and fed enterally as a result.

Aims

To establish the evidence base for aspiration risk in the adult population when eating/drinking with a cuff‐inflated tracheostomy.

Methods & Procedures

Systematic searches of seven key electronic databases, grey literature and reference lists of full‐text articles were conducted until January 2017. Two researchers independently identified eligible studies according to inclusion criteria (studies written in English, reporting aspiration rates in adult humans with inflated cuff tracheostomies). Methodological quality was assessed using the Downs and Black checklist. Owing to the heterogeneity of included studies in their design, population and measured outcomes, a narrative synthesis was employed.

Outcomes & Results

In total, 454 titles, 168 abstracts and 37 full papers were retrieved with 10 studies included in the final review. Methodological flaws and risk of bias were identified in all studies. Meta‐analysis was not feasible. Narrative synthesis found no study identified a statistically significantly higher incidence of aspiration in cuff‐inflated patients.

Conclusions & Implications

Evidence regarding aspiration risk is inconclusive. These results imply SLT services need to review policy to consider accepting referrals on a case‐by‐case basis, regardless of cuff status. Further research, though challenging to conduct, would inform best‐practice and policy/guideline development, allowing a consistent clinical approach.