bluuebunny/crossref_metadata_2025 huggingface dataset:
Applicability of Taylor's hypothesis in thermally driven turbulence
Authors: Kumar Abhishek , Verma Mahendra K.
Published: April 2018

In this paper, we show that, in the presence of large-scale circulation (LSC), Taylor’s hypothesis can be invoked to deduce the energy spectrum in thermal convection using real-space probes, a popular experimental tool. We perform numerical simulation of turbulent convection in a cube and observe that the velocity field follows Kolmogorov’s spectrum (
k
−5/3
). We also record the velocity time series using real-space probes near the lateral walls. The corresponding frequency spectrum exhibits Kolmogorov’s spectrum (
f
−5/3
), thus validating Taylor’s hypothesis with the steady LSC playing the role of a mean velocity field. The aforementioned findings based on real-space probes provide valuable inputs for experimental measurements used for studying the spectrum of convective turbulence.
Advances in synthetic gauge fields for light through dynamic modulation
Authors: Hey Daniel , Li Enbang
Published: April 2018

Photons are weak particles that do not directly couple to magnetic fields. However, it is possible to generate a photonic gauge field by breaking reciprocity such that the phase of light depends on its direction of propagation. This non-reciprocal phase indicates the presence of an effective magnetic field for the light itself. By suitable tailoring of this phase, it is possible to demonstrate quantum effects typically associated with electrons, and, as has been recently shown, non-trivial topological properties of light. This paper reviews dynamic modulation as a process for breaking the time-reversal symmetry of light and generating a synthetic gauge field, and discusses its role in topological photonics, as well as recent developments in exploring topological photonics in higher dimensions.
High quality whole genome sequence of an abundant Holarctic odontocete, the harbour porpoise (Phocoena phocoena)
Authors: Autenrieth Marijke , Hartmann Stefanie , Lah Ljerka , Roos Anna , Dennis Alice B. , Tiedemann Ralph
Published: April 2018

The harbour porpoise (Phocoena phocoena) is a highly mobile cetacean found in waters across the Northern hemisphere. It occurs in coastal water and inhabits water basins that vary broadly in salinity, temperature, and food availability. These diverse habitats could drive differentiation among populations. Here we report the first harbour porpoise genome, assembled de novo from a Swedish Kattegat individual. The genome is one of the most complete cetacean genomes currently available, with a total size of 2.7 Gb and 50% of the total length found in just 34 scaffolds. Using the largest 122 scaffolds, we were able to validate a high level of homology to the chromosome-level genome assembly of the closest related species for which such resource was available, the domestic cattle (Bos taurus). The draft annotation comprises 22,154 predicted gene models, which we further annotated through matches to the NCBI nucleotide database, GO categorization, and motif prediction. To infer the adaptive abilities of this species, as well as their population history, we performed a Bayesian skyline analysis, and produced results that are concordant with the demographic history of this species, including expansion and fragmentation events. Overall, this genome assembly, together with the draft annotation, represents a crucial addition to the limited genetic markers currently available for the study of porpoises and Phocoenidae conservation, phylogeny, and evolution.
3D Functional Ultrasound Imaging of Pigeons
Authors: Rau Richard , Kruizinga Pieter , Mastik Frits , Belau Markus , de Jong Nico , Bosch Johannes G. , Scheffer Wolfgang , Maret Georg
Published: April 2018

Recent advances in ultrasound Doppler imaging have allowed to visualize brain activity in small mammalian species such as rats and mice. In birds, this type of functional ultrasound imaging was impossible up to now because birds have physiological characteristics that are unfavorable for current functional ultrasound acquisition schemes. Here, we introduce a high-definition functional ultrasound acquisition method (HDfUS) acquiring 20,000 frames per second continuously. This enabled first successful functional studies on awake pigeons subjected to auditory and visual stimulation. We show that the improved spatiotemporal resolution and sensitivity of HDfUS allows to visualize and investigate the temporally resolved 3D neural activity evoked by a complex stimulation pattern, such as a moving light source. This illustrates the enormous potential of HDfUS imaging to become a new standard functional brain imaging method revealing unknown, stimulus related hemodynamics at excellent signal-to-noise ratio and spatiotemporal resolution.

Highlights

- We describe a novel ultrafast functional ultrasound technique (HDfUS)

- HDfUS offers continuous recording with unmatched spatiotemporal resolution

- HDfUS allows to resolve complex 4D neurovascular responses in the brain

- First fUS study on non-mammalian species
A novel framework for inferring parameters of transmission from viral sequence data
Authors: Lumby Casper K , Nene Nuno R , Illingworth Christopher J R
Published: April 2018

Transmission between hosts is a critical part of the viral lifecycle. Recent studies of viral transmission have used genome sequence data to evaluate the number of particles transmitted between hosts, and the role of selection as it operates during the transmission process. However, the interpretation of sequence data describing transmission events is a challenging task. We here present a novel and comprehensive framework for using short-read sequence data to understand viral transmission events. Our model describes transmission as an event involving whole viruses, rather than independent alleles. We demonstrate how selection and noisy sequence data may each affect inferences of the population bottleneck, and identify circumstances in which selection for increased viral transmission may or may not be identified. Applying our model to data from a previous experimental transmission study, we show that our approach grants a more quantitative insight into viral transmission, inferring that between 2 to 6 viruses initiated infection, and allowing for a more informed interpretation of transmission events. While our model is here applied to influenza transmission, the framework we present is highly generalisable to other systems. Our work provides new opportunities for studying viral transmission.
AchE-OGT dual inhibitors: Potential Partners in Handling Alzheimer’s Disease
Authors: Sharma Mukta , Jainarayanan Ashwin K.
Published: April 2018

The emerging role of O-GlcNAc Transferase (OGT) and tau protein in Alzheimer’s disease (AD) holds promises for the treatment of this life-threatening neurodegenerative disorder. In view of the availability of 3D structure of OGT, we attempted to develop structure-based pharmacophore model to elucidate specific structural requirements for binding of inhibitors to the active site of OGT. During the course of study we discovered that donepezil, an old and trusted Acetylcholinesterase (AchE) inhibitor also possess the pharmacophoric sites important for interaction with OGT active site. To further explore the specific interactions of donepezil with OGT, we performed molecular docking studies using CDocker. The results of molecular docking and structure-based pharmacophore mapping revealed that donepezil has the required structural features to interact with various OGT active site amino acids like Lys842, His920, Leu653, Gly654, Asn838, and Thr921 in addition to its AchE interaction abilities. Our findings could be an important breakthrough in the design of OGT specific and/or AchE OGT dual inhibitors.
Correct CYFIP1 dosage is essential for synaptic inhibition and the excitatory/inhibitory balance.
Authors: Davenport Elizabeth C , Szulc Blanka , Drew James , Taylor James , Morgan Toby , Higgs Nathalie F , Lopez-Domenech Guillermo , Kittler Josef T
Published: April 2018

Altered excitatory/inhibitory balance is implicated in neuropsychiatric disorders but the genetic aetiology of this is still poorly understood. Copy number variations in CYFIP1 are associated with autism, schizophrenia and intellectual disability but the role of CYFIP1 in regulating synaptic inhibition or excitatory/inhibitory balance remains unclear. We show, CYFIP1, and its paralogue CYFIP2, are enriched at inhibitory postsynaptic sites. While upregulation of CYFIP1 or CYFIP2 increased excitatory synapse number and the frequency of miniature excitatory postsynaptic currents (mEPSCs), it had the opposite effect at inhibitory synapses, decreasing their size and the amplitude of miniature inhibitory postsynaptic currents (mIPSCs). Contrary to CYFIP1 upregulation, its loss in vivo, upon conditional knockout in neocortical principal cells, increased expression of postsynaptic GABA
A
receptor β2/3-subunits and neuroligin 3 and enhanced synaptic inhibition. Thus, CYFIP1 dosage can bi-directionally impact inhibitory synaptic structure and function, potentially leading to altered excitatory/inhibitory balance and circuit dysfunction in CYFIP1-associated neurodevelopmental disorders.
A multicellular rosette-mediated collective dendrite extension
Authors: Fan Li , Kovacevic Ismar , Heiman Maxwell , Bao Zhirong
Published: April 2018

Coordination of neurite morphogenesis with surrounding tissues is crucial to the establishment of neural circuits, but the underlying cellular and molecular mechanisms remain poorly understood. We show that neurons in a C. elegans sensory organ, called the amphid, undergo a collective dendrite extension to initiate formation of the sensory nerve. The amphid neurons first assemble into a multicellular rosette. The vertex of the rosette, which becomes the dendrite tips, is attached to the anteriorly migrating epidermis and carried to the sensory depression, extruding the dendrites away from the neuronal cell bodies. Multiple adhesion molecules including DYF-7, SAX-7, HMR-1 and DLG-1 function redundantly in rosette-to-epidermis attachment. PAR-6 is localized to the rosette vertex and dendrite tips, and promotes DYF-7 localization and dendrite extension. Our results suggest a collective mechanism of neurite extension that is distinct from the classical pioneer-follower model and highlight the role of mechanical cues from surrounding tissues in shaping neurites.
Design and analysis of a Proportional-Integral-Derivative controller with biological molecules
Authors: Chevalier Michael , Gómez-Schiavon Mariana , Ng Andrew , El-Samad Hana
Published: April 2018

The ability of cells to regulate their function through feedback control is a fundamental underpinning of life. The capability to engineer de novo feedback control with biological molecules is ushering in an era of robust functionality for many applications in biotechnology and medicine. To fulfill their potential, feedback control strategies implemented with biological molecules need to be generalizable, modular and operationally predictable. Proportional-Integral-Derivative (PID) control fulfills this role for technological systems and is a commonly used strategy in engineering. Integral feedback control allows a system to return to an invariant steady-state value after step disturbances, hence enabling its robust operation. Proportional and derivative feedback control used with integral control help sculpt the dynamics of the return to steady-state following perturbation. Recently, a biomolecular implementation of integral control was proposed based on an antithetic motif in which two molecules interact stoichiometrically to annihilate each other’s function. In this work, we report how proportional and derivative implementations can be layered on top of this integral architecture to achieve a biochemical PID control design. We illustrate through computational and analytical treatments that the addition of proportional and derivative control improves performance, and discuss practical biomolecular implementations of these control strategies.
Transcriptionally induced enhancers in the macrophage immune response toMycobacterium tuberculosisinfection
Authors: Denisenko Elena , Guler Reto , Mhlanga Musa , Suzuki Harukazu , Brombacher Frank , Schmeier Sebastian
Published: April 2018

Background

Tuberculosis is a life-threatening infectious disease caused byMycobacterium tuberculosis(M.tb).M.tbsubverts host immune responses to build a favourable niche and survive inside of host macrophages. Macrophages can control or eliminate the infection, if appropriate transcriptional programs are activated. The role of transcriptional enhancers in the activation and maintenance of these programs remains unexplored.

Results

We analysed transcribed enhancers inM.tb-infected mouse bone marrow-derived macrophages. We established a link between knownM.tb-responsive transcription factors and transcriptional activation of enhancers and their target genes. Our data suggest that enhancers might drive the macrophage response via transcriptional activation of key immune genes, such as Tnf, Tnfrsf1b, Irg1, Hilpda, Ccl3, and Ccl4. We report enhancers acquiring transcriptionde novoupon infection. Finally, we link highly transcriptionally induced enhancers to the activation of genes with previously unappreciated roles inM.tbinfection, such as Fbxl3, Tapt1, Edn1, and Hivep1.

Conclusions

Our findings extend current knowledge of the regulation of macrophage responses toM.tbinfection and provide a basis for future functional studies on enhancer-gene interactions in this process.
Azithromycin reduces systemic inflammation and provides survival benefit in murine model of polymicrobial sepsis
Authors: Patel Anasuya , Joseph Jiji , Periasamy Hariharan , Mokale Santosh
Published: April 2018

Sepsis is a life threatening systemic inflammatory condition triggered as a result of excessive host immune response to infection. In the past, drugs modulating immune reactions have demonstrated protective effect in sepsis. Azithromycin (macrolide antibiotic) with immunomodulatory activity was therefore evaluated in combination with ceftriaxone in a more clinically relevant murine model of sepsis induced by caecal ligation and puncture (CLP). First, mice underwent CLP and 3 h later were administered with vehicle, sub-effective dose of ceftriaxone (100 mg/kg,subcutaneous) alone or in combination with immunomodulatory dose of azithromycin (100 mg/kg,intraperitoneal). Survival was then monitored for 5 days. Parameters like body temperature, blood glucose, total white blood cell count, plasma glutathione (GSH), plasma and lung myeloperoxidase (MPO) as well as cytokine (interleukin IL-6, IL-1β, tumor necrosis factor-α) levels along with bacterial load in blood, peritoneal fluid and lung homogenate were measured 18 h after CLP challenge. Combination group significantly improved the survival of CLP mice. It attenuated the elevated levels of inflammatory cytokines and MPO in plasma and lung tissue and increased the body temperature, blood glucose and GSH which were otherwise markedly decreased in CLP mice. Ceftriaxone exhibited significant reduction of bacterial count in blood, peritoneal fluid and lung homogenate, while co-administration of azithromycin did not further reduce it. This confirms that survival benefit by azithromycin was due to immunomodulation and not by its antibacterial action. Findings of this study indicate that azithromycin in combination with ceftriaxone could exhibit clinical benefit in sepsis.
Endothelial cells secreted ET-1 augments DN via inducing EM accumulation of MCs in ETBR−/− mice
Authors: Zou Hong-hong , Wang Li , Shen Yun-feng , Zheng Xiao-xu , Xu Gao-si
Published: April 2018

ETBR deficiency may contribute to the progression of DN in a STZ model, but the underlying mechanism is not fully revealed. In this study, STZ-diabetic ETBR−/− mice was characterized by increased serum creatinine, urinary albumin and ET-1 expression, and enhanced glomerulosclerosis compared with STZ-diabetic WT mice. HG conditioned media of ETBR−/− endothelial cells promoted MC proliferation and upregulated ECM-related proteins, and ET-1 knockout in endothelial cells or inhibition of ET-1/ETAR in MC suppressed MC proliferation. ET-1 was over-expressed in ETBR−/− endothelial cells and was regulated by NF-kapapB pathway. And ET-1/ETBR suppressed NF-kappaB via eNOS to modulate ET-1 in endothelial cells. Furthermore, ET-1/ETAR promoted RhoA/ROCK pathway in MC, and accelerated MC proliferation and ECM accumulation. In vivo experiments proved ETBR−/− mice inhibited NF-kappaB pathway to ameliorate DN and eNOS mice had similar results. Hence, in HG-exposed ETBR−/− endothelial cells, suppression of ET-1/ETBR activated NF-kappaB pathway via inhibiting eNOS to secrete large amount of ET-1. Due to the communication between endothelial cells and MCs, ET-1/ETAR in MC promoted RhoA/ROCK pathway to accelerate MC proliferation and ECM accumulation.
Effects of protein size, thermodynamic stability, and net charge on cotranslational folding on the ribosome
Authors: Farías-Rico José Arcadio , Selin Frida Ruud , Myronidi Ioanna , Frühauf Marie , Heijne Gunnar von
Published: April 2018

During the last five decades, studies of protein folding in dilute buffer solutions have produced a rich picture of this complex process. In the cell, however, proteins can start to fold while still attached to the ribosome (cotranslational folding) and it is not yet clear how the ribosome affects the folding of protein domains of different sizes, thermodynamic stabilities, and net charges. Here, by using arrest peptides as force sensors and on-ribosome pulse proteolysis, we provide a comprehensive picture of how the distance from the peptidyl transferase center in the ribosome at which proteins fold correlates with protein size. Moreover, an analysis of a large collection of mutants of theE. coliribosomal protein S6 shows that the force exerted on the nascent chain by protein folding varies linearly with the thermodynamic stability of the folded state, and that the ribosome environment disfavors folding of domains of high net-negative charge.
Gene regulatory network reconstruction incorporating 3D chromosomal architecture reveals key transcription factors and DNA elements driving neural lineage commitment
Authors: Malysheva Valeriya , Mendoza-Parra Marco Antonio , Blum Matthias , Spivakov Mikhail , Gronemeyer Hinrich
Published: April 2018

Lineage commitment is a fundamental process that enables the morphogenesis of multicellular organisms from a single pluripotent cell. While many genes involved in the commitment to specific lineages are known, the logic of their joint action is incompletely understood, and predicting the effects of genetic perturbations on lineage commitment is still challenging. Here, we devised a gene regulatory network analysis approach, GRN-loop, to identify key cis-regulatory DNA elements and transcription factors that drive lineage commitment. GRN-loop is based on signal propagation and combines transcription factor binding data with the temporal profiles of gene expression, chromatin state and 3D chromosomal architecture. Applying GRN-loop to a model of morphogen-induced early neural lineage commitment, we discovered a set of driver transcription factors and enhancers, some of them validated in recent data and others hitherto unknown. Our work provides the basis for an integrated understanding of neural lineage commitment, and demonstrates the potential of gene regulatory network analyses informed by 3D chromatin architecture to uncover the key genes and regulatory elements driving developmental processes.
High-resolution experimental and computational electrophysiology reveals weak β-lactam binding events in the porin PorB
Authors: Bartsch Annika , Llabrés Salomé , Pein Florian , Kattner Christof , Schön Markus , Diehn Manuel , Tanabe Mikio , Munk Axel , Zachariae Ulrich , Steinem Claudia
Published: April 2018

The permeation of most antibiotics through the outer membrane of Gram-negative bacteria occurs through porin channels. To design drugs with increased activity against Gram-negative bacteria in the face of the antibiotic resistance crisis, the strict constraints on the physicochemical properties of the permeants imposed by these channels must be better understood. Here we show that a combination of high-resolution electrophysiology, new noise-filtering analysis protocols and atomistic biomolecular simulations reveals weak binding events between the β-lactam antibiotic ampicillin and the porin PorB from the pathogenic bacteriumNeisseria meningitidis. In particular, an asymmetry often seen in the electrophysiological characteristics of ligand-bound channels is utilised to characterise the binding site and molecular interactions in detail, based on the principles of electro-osmotic flow through the channel. Our results provide a rationale for the determinants that govern the binding and permeation of zwitterionic antibiotics in anion-selective porin channels.
Large time step discrete-time modeling of sharp wave activity in hippocampal area CA3
Authors: Malerba Paola , Rulkov Nikolai F. , Bazhenov Maxim
Published: April 2018

Reduced models of neuronal spiking activity simulated with a fixed integration time step are frequently used in studies of spatio-temporal dynamics of neurobiological networks. The choice of fixed time step integration provides computational simplicity and efficiency, especially in cases dealing with large number of neurons and synapses operating at a different level of activity across the population at any given time. A network model tuned to generate a particular type of oscillations or wave patterns is sensitive to the intrinsic properties of neurons and synapses and, therefore, commonly susceptible to changes in the time step of integration. In this study, we analyzed a model of sharp-wave activity in the network of hippocampal area CA3, to examine how an increase of the integration time step affects network behavior and to propose adjustments of intrinsic properties of neurons and synapses that help minimize or remove the damage caused by the time step increase.

Highlights

Spiking models of neural network activity are sensitive to the integration step

Larger integration time steps are preferable in simulating large networks

Case study of CA3 sharp waves shows time step increase damages network dynamics

Neuronal and synaptic parameters adjustments rescue the dynamics at large time step1
S-Nitrosylation of STIM1 by neuronal nitric oxide synthase inhibits store-operated Ca2+ entry
Authors: Gui Le , Zhu Jinhui , Lu Xiangru , Sims Stephen M. , Lu Wei-Yang , Stathopulos Peter B. , Feng Qingping
Published: April 2018

Store-operated Ca2+ entry (SOCE) mediated by stromal interacting molecule-1 (STIM1) and Orai1 represents a major route of Ca2+ entry in mammalian cells and is initiated by STIM1 oligomerization in the endoplasmic or sarcoplasmic reticulum (ER/SR). However, the effects of nitric oxide (NO) on STIM1 function are unknown. Neuronal NO synthase (nNOS) is located in the SR of cardiomyocytes. Here, we show that STIM1 is susceptible to S-nitrosylation. nNOS deficiency or inhibition enhanced Ca2+ release-activated Ca2+ channel current (ICRAC) and SOCE in cardiomyocytes. Consistently, NO donor S-nitrosoglutathione (GSNO) inhibited STIM1 puncta formation and ICRAC in HEK293 cells, but this effect was absent in cells expressing the Cys49Ser/Cys56Ser STIM1 double mutant. Furthermore, NO donors caused Cys49 and Cys56-specific structural changes associated with reduced protein backbone mobility, increased thermal stability and suppressed Ca2+-depletion-dependent oligomerization of the luminal Ca2+-sensing region of STIM1. Collectively, our data show that S-nitrosylation of STIM1 suppresses oligomerization via enhanced luminal domain stability and rigidity, and inhibits SOCE in cardiomyocytes.
A member of the ferlin calcium sensor family is essential forToxoplasma gondiirhoptry secretion
Authors: Coleman Bradley I. , Saha Sudeshna , Sato Seiko , Engelberg Klemens , Ferguson David J. P. , Coppens Isabelle , Lodoen Melissa B. , Gubbels Marc-Jan
Published: April 2018

Invasion of host cells by apicomplexan parasites such asToxoplasma gondiiis critical for their infectivity and pathogenesis. InToxoplasma, secretion of essential egress, motility and invasion-related proteins from microneme organelles is regulated by oscillations of intracellular Ca2+. Later stages of invasion are considered Ca2+-independent, including the secretion of proteins required for host cell entry and remodeling from the parasite’s rhoptries. We identified a family of threeToxoplasmaproteins with homology to the ferlin family of double C2 domain-containing Ca2+sensors. In humans and model organisms such Ca2+sensors orchestrate Ca2+-dependent exocytic membrane fusion with the plasma membrane. One ferlin that is conserved across the Apicomplexa, TgFER2, localizes to the parasite’s cortical membrane skeleton, apical end, and rhoptries. Unexpectedly, conditionally TgFER2-depleted parasites secreted their micronemes normally and were completely motile. However, these parasites were unable to invade host cells and were therefore not viable. Specifically, knockdown of TgFER2 prevented rhoptry secretion and these parasites failed to form the moving junction on the parasite-host interface necessary for host cell invasion. Collectively, these data demonstrate that the putative Ca2+sensor TgFER2 is required for the secretion of rhoptries. These findings provide the first regulatory and mechanistic insights into this critical yet poorly understood aspect of apicomplexan host cell invasion.

Graphical abstract
Theta-gamma coupling: a nonlinear dynamical model
Authors: Sheremet Alex , Zhou Yuchen , Kennedy Jack P. , Qin Yu , Burke Sara N. , Maurer Andrew P.
Published: April 2018

Cross-frequency coupling in the hippocampus has been hypothesized to support higher-cognition functions. While gamma modulation by theta is widely accepted, evidence of phase-coupling between the two frequency components is so far unconvincing. Our observations show that theta and gamma energy increases with rat speed, while the overall nonlinearity of the LFP trace also increases, suggesting that energy flow is fundamental for hippocampal dynamics. This contradicts current representations based on the Kuramoto phase model. Therefore, we propose a new approach, based on the three-wave equation, a universally-valid nonlinear-physics paradigm that synthesizes the effects of leading order, quadratic nonlinearity. The paradigm identifies bispectral analysis as the natural tool for investigating LFP cross-frequency coupling. Our results confirm the effectiveness of the approach by showing unambiguous coupling between theta and gamma. Bispectra features agree with predictions of the three-wave model, supporting the conclusion that cross-frequency coupling is a manifestation of nonlinear energy transfers.
A CuII complex with an carbamoylcyanonitrosomethanide ligand formed in situ by the nucleophilic addition of water to dicyanonitrosomethanide: structure, spectral and magnetic properties
Authors: Potočňák Ivan , Bukrynov Oleksandr , Kliuikov Andrii , Čižmár Erik , Vitushkina Svitlana , Váhovská Lucia , Dušek Michal
Published: April 2018

The complex (2,2′-biquinoline-κ2
N,N′)(carbamoylcyanonitrosomethanide-κ2
N,O)chloridocopper(II) acetonitrile monosolvate, [Cu(C3H2N3O2)Cl(C18H12N2)]·CH3CN or [Cu(ccnm)Cl(biq)]·acn (acn is acetonitrile, biq is 2,2′-biquinoline and ccnm is carbamoylcyanonitrosomethanide), (I), was prepared as a result of nucleophilic addition of water to the dicyanonitrosomethanide ion in the presence of CuII and biq. IR spectroscopy confirmed the presence of ccnm, biq and acn in (I). The solid-state structure consists of the neutral complex containing ccnm and biq ligands, coordinated to the CuII atom in a bidendate chelating manner, and a chloride ligand, resulting in a distorted tetragonal pyramidal coordination of CuII. The asymmetric unit is supplemented by one molecule of solvated acn which, along with the nitrile group of ccnm, serves as an acceptor in intermolecular hydrogen bonding, creating infinite chains along the b axis. Magnetic measurements revealed a paramagnetic behaviour with a very small Weiss temperature Θ = −0.32 K and high anisotropy of the g tensor (g

x
= 2.036, g

y
= 2.120 and g

z
= 2.205).
Accelerated tax depreciation and farm investment: evidence from Michigan
Authors: Polzin Leonard , Wolf Christopher A. , Black J. Roy
Published: April 2018

Purpose

The purpose of this paper is to examine the use of accelerated depreciation deductions, which includes Section 179 and bonus depreciation, taken in the first year of asset life by Michigan farms. The frequency, value and influence of accelerated depreciation on farm investment are also analyzed.

Design/methodology/approach

Accrual adjusted income statements, balance sheets, depreciation schedules, and income tax information for 66 Michigan farms from 2004 to 2014 provide data for the analysis. The present value of the accelerated deduction and change in the cost of capital were calculated. Finally, investment elasticities were used to arrive at the change in investment due to accelerated depreciation.

Findings

Accelerated depreciation was utilized across all applicable asset classes. Section 179 was used more often than bonus depreciation in part because it was available in all the examined years. Based on actual farm business use, accelerated depreciation lowered the cost of capital for the operations resulting in an estimated increase in investment of 0.27 to 11.6 percent depending on asset class.

Originality/value

The data utilized are of a detail not available in previous investigations which used either aggregate data or estimated rather than the observed use of accelerated depreciation. This analysis reveals that accelerated depreciation as used by commercial farms lowers the cost of capital and thus encourages investment particularly in machinery and equipment.
Dynamic relationship between Nigeria-US exchange rate and crude oil price
Authors: Raji Jimoh Olajide , Idowu Abdulkadir Rihanat , Badru Bazeet Olayemi
Published: April 2018

Purpose

The purpose of this paper is to investigate the dynamic relationship between Nigeria-US exchange rate (XR) and crude oil price (OILP) using daily data from 1 January 2001 to 31 December 2015.

Design/methodology/approach

The study uses alternative methods, including vector autoregressive-generalised autoregressive conditional heteroskedasticity (VAR-GARCH) within the framework of Baba-Engle-Kraft-Kroner model, constant conditional correlation (CCC)-GARCH and dynamic conditional correlation (DCC)-GARCH models.

Findings

The results from the VAR-GARCH model indicate unidirectional cross-market mean spillovers from oil market (OILM) to foreign exchange market (FXM). In addition, the results show a positive effect of OILP on XR, suggesting that an increase in OILP appreciates Nigerian currency relative to US dollar and a fall in OILP depreciates it. The authors find that the effects of cross-volatility spillovers between the OILM and FXM are bidirectional. The CCC results indicate positive correlations of returns of 16 per cent between the FXM and OILM. Finally, the DCCs results indicate positive correlations between the two markets since the fourth quarter of 2008 (the world financial crisis period) until the recent period of world oil glut and slow demand for crude oil.

Research limitations/implications

Following the depreciation of the Nigerian currencyvis-á-visUS dollar since the onset of the recent world oil glut and lower oil prices, Nigerian authorities should embark on subsidy reform, such as reduction in fuel subsidies. This may enable the release of fiscal resources that may be used to either rebuild fiscal space lost or finance investment in non-oil sectors in order to reduce overdependence on oil income. Lower fiscal revenues, coupled with the risk that crude oil maintains its low price for some time, imply that government should reduce its expenditure, and continue to draw on available accumulated funds from the excess crude account for some time until the real depreciation required for adjustment is achieved.

Originality/value

Studies on volatility spillovers between OILM and FXM are limited in the literature, particularly in Nigerian case. Moreover, the study employs different approaches for broader analysis. These alternative methods, a clear departure from the previous studies, provide comprehensive dynamic nature of the relationship between the FXM and OILM.
Exploring the long-term trade-off between efficiency and value creation in horizontal M&As
Authors: Akpan Mfon Nathaniel Udo , Aik Nai Chiek , Wanke Peter Fernandes , Chau Wong Hong
Published: April 2018

Purpose

The purpose of this paper is to investigate the voluntary horizontal M&A impact on operating performance in Nigeria between 1995 and 2012 under different complementary approaches.

Design/methodology/approach

Residual income valuation (RIV), economic value-added (EVA), data envelopment analysis (DEA) and stochastic frontier analysis (SFA).

Findings

Results showed a statistically significant improvement in the technical efficiency of both bidder and target companies, the reduced efficiency levels of the bidder firms under DEA scores reveals the specifics of the productive technology. This may suggest that resulting merged companies in Nigeria may have not even become too big in scale or even reached the most productive scale size, despite their almost monopolistic position in the sector. This happens because the scale size of the sector is small per se, implying that the investments necessary to achieve synergistic gains have to be partially covered by price increases.

Practical implications

This study will guide both the M&A practitioners, investment banks, and the policy makes. In terms of having to review M&A policy as well as seeing to the improvement in the infrastructural needs.

Social implications

With improved performance, employment can be created thereby giving employment to the youths. This will reduce social problems.

Originality/value

From the literature and records, no long-term operating performance on voluntary mergers and acquisitions has not been carried out in Nigeria. The paper seeks to know the fundamental value of the firms after these transactions with the current methodology that is acceptable from the literature.
Bank customer loyalty and satisfaction: the influence of virtual e-CRM
Authors: Mang’unyi Eric E. , Khabala Oumar T. , Govender Krishna Kistn
Published: April 2018

Purpose

The purpose of this paper is to investigate the mediating role of customer satisfaction (CS) in the electronic-customer relationship management (e-CRM) and customer’s loyalty (CL) relationship, using data from the customers of one of the largest retail banks in Kenya.

Design/methodology/approach

Using survey mode, the study was administered to 90 samples (of which 78 were returned and usable), with data analysed using exploratory factor analysis to determine scale validity, and path analysis and multiple regression modelling to test hypotheses.

Findings

This study revealed that the interaction between e-CRM transaction features and CS was statistically significant and predicted CL, however, the interaction did not significantly account for more variance than just e-CRM features and CS. The path analysis revealed a lack of potential significant mediation effects of CS on the relationship between e-CRM and CL.

Research limitations/implications

Although this research may have sampling limitations and also that the model fit is confined in a single bank/service industry, the estimated model was reasonable enough and has the potential of being repeated in future studies.

Originality/value

The principle contribution of the present research is it supplies unique learning to bank managers and scholars alike through conceptualising and subsequently empirically verifying the path e-CRM and e-loyalty via CS, and that CS does not mediate the relationship between the aforementioned constructs. By investigating the e-CRM practices of an existing case study, it provides insights of the issue and compare to literature, therefore supplying a thorough and detailed analysis to understand the phenomenon under investigation valuable for banking sector.
Sport events at the community level
Authors: Miragaia Dina Alexandra Marques , da Costa Carla D.M. , Ratten Vanessa
Published: April 2018

Purpose

The purpose of this paper is to identify motives that lead students and teachers of sports science to participate voluntarily in the organization of sport events at a community level.

Design/methodology/approach

A questionnaire composed of five dimensions, expression of values, concern for the community, interpersonal contacts, vocational guidance and personal growth/development, was given to a sample of students and teachers. Then a confirmatory factorial analysis was applied to the five dimensions and descriptive statistics was used to identify the ranking in terms of the reasons why teachers and students decide to engage in extracurricular activities. The Mann-Whitney U-Test was used to identify significant differences between the two groups.

Findings

Teachers and students consider that the main reasons for their involvement are related to expression of values, concern for the community and vocational guidance. Significant differences were found indicating that for students, gaining experience for future jobs is one of their priorities but for the teachers they consider that helping others and contributing to the good of society are the main reasons.

Research limitations/implications

The implications for organizers of community sport events are that different rationale for contributing need to be taken into account.

Originality/value

This study contributes to the pedagogical strategies that can be used to improve the training of the sports science students. It is important to note that the involvement of students and teachers in extracurricular activities can benefit from their integration into the labor market.
Evaluating the resource use efficiency of government colleges in Punjab (India)
Authors: Kaur Harpreet , Bhalla G.S.
Published: April 2018

Purpose

In the present era, government colleges in Punjab are facing cutthroat competition on three fronts, i.e. financial constraints and insufficiency of government grants, falling number of students and the shortage of teaching staff in the colleges because of stiff competition and other reasons. Thus, the purpose of this study is to evaluate the resource use efficiency of government colleges in Punjab.

Design/methodology/approach

The study covered 15 general degree government colleges from various districts of Punjab. Secondary data for the study were collected from financial budgets, income and expenditure statements and self study reports of the colleges. The data envelopment analysis was conducted using the CCR model and BCC model.

Findings

The technical efficiency results suggest that colleges analyzed in this study are operating at a moderate level of efficiency relative to each other. Most of the colleges were found to be inefficient during the study period. Only one college was found consistently efficient during all the years of the study. Moreover, input and output slacks exist in many of the colleges.

Research limitations/implications

To achieve the efficiency level, the colleges need to improve their utilization of resources and the enrollment rate at a given level of resources. To increase the efficiency of the colleges, the Government of India needs to reform their budgeting system.

Originality/value

Punjab is a well-known state of India and public higher education sector plays important role in the education system. This research provides a new insight to the efficiency of the government colleges.
Reincorporations: a comparison between Greek and Cyprus law
Authors: Papadopoulos Thomas
Published: April 2018

Purpose

This paper aims to analyse the legal framework of reincorporations and subsequent change of applicable law in Greece and Cyprus. A comparison between Greek Law and Cyprus Law is drawn. This paper highlights possible required reforms. Cyprus has a quite detailed legal framework of voluntary inbound and outbound reincorporations. While Greece has certain provisions on outbound reincorporations, it does not have any provisions on inbound reincorporations. The compatibility of these national provisions with internal market rules, as interpreted by the case law of the Court of Justice of the EU (CJEU), is discussed.

Design/methodology/approach

This paper follows a comparative approach. After a careful analysis of each national legal framework, a comparison between Greek law and Cyprus law follows. This paper also follows an EU law approach.

Findings

These two jurisdictions present some differences. Cyprus adopting the incorporation theory has a detailed, sophisticated and flexible legal framework of reincorporations. Although Greece adopting the real seat theory has some special provisions for outbound reincorporations, there are no specific provisions for inbound reincorporations. Inbound reincorporations are possible under Greek law, but the absence of detailed provisions is against legal certainty. Cyprus law on reincorporations could be used as an example for Greek legislature. However, possible EU harmonisation of seat transfers is expected to have an immense impact on national provisions for reincorporations.

Practical implications

Reincorporations constitute a significant corporate restructuring technique with important practical implications on the economy. Apart from academics, this paper attracts the interest of lawyers, managers, accountants, officers of supervisory and regulatory bodies and policymakers engaged with reincorporations.

Originality/value

This is one of the few academic papers comparing Greek and Cyprus company law and private international law. It is the first paper that compares the Greek and Cyprus legal framework of reincorporations.
Implementation issues of a design management indicator system
Authors: Radici Fraga Paula Görgen , Bernardes Maurício Moreira e Silva , Vieira Darli Rodrigues , Chain Milena Chang
Published: April 2018

Purpose

The purpose of this paper is to present and discuss the process and results achieved from the implementation of a design management indicator system in four product development companies.

Design/methodology/approach

To this end, instruments and techniques for implementing and collecting composite data were adopted.

Findings

The implementation made it possible to test the system metrics, and the analysis of the results enabled the identification of factors that hinder a successful implementation.

Originality/value

Design is being recognized as providing significant economic, social, and environmental benefits, and as it becomes a part of the management process, it can have an impact on business performance. Therefore, information sharing through indicator systems that consider factors that generate reliable and quantifiable information has become fundamental.
The questionnaire on productivity attributes (QPA)
Authors: Kamble Raju Sheshrao , Wankhade Lalit Narendra
Published: April 2018

Purpose

Although there are many studies investigating attributes affecting productivity, the research into measurement of those attributes has been incomplete. In an attempt to bridge this gap, the authors reviewed the productivity literature, identified and integrated previously described attributes, and developed a measure to estimate those attributes. The developed questionnaire – questionnaire on productivity attributes (QPA) – is based on a five-dimensional conceptual framework, which consisted of human resource management, management strategy, organizational culture, production methodology, and performance. A model that measures a way to construct a linear scale from ordinal data has also been introduced. The paper aims to discuss these issues.

Design/methodology/approach

Initially, a pilot survey among Indian academic and industrial experts as well as employees working in manufacturing industries was conducted to optimize clarity, readability, and construction of the QPA. After pilot-testing, the 45 QPA items were further field surveyed amongst a representative sample of 311 Indian engineers, managers, and workers from manufacturing industries. One-way analysis of variance is performed to examine whether there are differences among engineers, managers, and workers in the understandability or applicability of QPA. Exploratory factor analysis is used to confirm the five-dimensional conceptual framework. Also, infit and outfit measures have been used to check the QPA model fit. To increase confidence, all retained items are tested for goodness-of-fit test. Finally, the functioning of optimal response categorization of the QPA is demonstrated in terms of frequencies, average measures, and standard error.

Findings

A five-dimensional conceptual framework is identified. A generic short scale was constructed. Finally, the developed questionnaire provides new insights into how to avoid the trade-offs commonly observed in productivity research.

Originality/value

The newly designed QPA appears as a general measure for productivity attributes which can be used by scholars and practitioners to conduct basic research on productivity improvement in various industries.
The influencing outcomes of job engagement: an interpretation from the social exchange theory
Authors: Yin Nan
Published: April 2018

Purpose

Job engagement is a positive, fulfilling, work-related state of an individual, the perfect link between individual characteristics, job factors and job performance and the important path of an organization creating competitive advantages. Based on the viewpoint of the social exchange theory, the study assumes that employees will generate different influencing outcomes, which are, in order, task performance, organizational citizenship behavior, job burnout and counter-productive work behavior (CWB), according to the degree to which they psychologically expect that job engagement could receive organizational rewards, and discusses the relationships between job engagement and task performance, organizational citizenship behavior and other variables. The paper aims to discuss these issues.

Design/methodology/approach

Data were collected from the employees working as the salesmen from 48 computer and computer parts sales companies. The questionnaires of the study were the paired questionnaires. In total, 150 supervisor questionnaires and 633 employee questionnaires have been distributed. Under every sales head, there were some employees. In total, 501 valid paired questionnaires were collected. AMOS 23.0 was employed to process the data in the structural equation modeling and the causal relationships among all the factors were explored.

Findings

The results revealed that employee job engagement had positive influence on task performance and organizational citizenship behavior and had negative influence on job burnout and counter-productive work behavior; among all the moderating variables, organizational justice just significantly and negatively moderates job engagement and CWB.

Originality/value

Job engagement is an actively and fully absorbing state of an individual in the work, the perfect link among individual characteristics, job factors and job engagement and the important path of an organization creating competitive advantages. Most of the past studies have explored the positive effects of job engagement. This study tries to explore the positive and negative effects of employee’s job engagement based on the social exchange theory.