bluuebunny/crossref_metadata_2025 huggingface dataset:
MULTIMODAL IMAGING DURING THE EVOLUTION OF BLOOD–BRAIN BARRIER DISRUPTION MACULOPATHY
Authors: Pal Bikramjit P. , Palosaari Tapani , Kivelä Tero
Published: January 2017

Purpose:

To highlight the course of blood–brain barrier disruption maculopathy in a patient with successfully managed relapsed central nervous system lymphoma.

Methods:

Case report with fundus autofluorescence and optical coherence tomography imaging, and literature review.

Results:

A 57-year-old patient diagnosed with central nervous system large B-cell lymphoma had a normal ophthalmic evaluation on his first visit. Subsequently, when his malignancy recurred locally, he was started on blood–brain barrier disruption therapy and intraarterial methotrexate. During the course of the therapy, he developed bilateral retinal pigment epithelial abnormalities located in the foveal and perifoveal zones. The changes were first mildly progressive and then marginally regressive in nature with minimal eventual loss of visual acuity to 20/32 and 20/25 in his right and left eye, respectively.

Conclusion:

Maculopathy is a known complication in patients with central nervous system malignancies undergoing blood–brain barrier disruption. A detailed clinical evaluation using fundus autofluorescence and high-definition optical coherence tomography are informative in managing such patients.
XEN Gel Stent Internal Ostium Occlusion: Ab-Interno Revision
Authors: Pinto Ferreira Nuno , Abegão Pinto Luis , Marques-Neves Carlos
Published: January 2017

Minimally invasive glaucoma surgery aims to provide a safer and less-invasive means of reducing IOP compared with traditional surgery, with the goal of reducing the need for topical medications. The XEN gel stent is an ab-interno minimally invasive glaucoma surgery device that approaches intraocular pressure reduction by creating a subconjunctival drainage pathway. As with any new device there is lack of experience and knowledge about its long-term results in terms of efficacy, technique, and complications. We report a clinical case of a XEN blood clot internal ostium obstruction and how it was managed. The ab-interno approach with microforceps seems a minimally invasive, safe, and effective procedure.
Human Papillomavirus Genotyping of Incidental Malignant and Premalignant Lesions on Hemorrhoidectomy Specimens
Authors: Hui Yiang , Quddus M. Ruhul , Murthy Jayasimha N. , Yang Dongfang , Sung C. James , Lu Shaolei , Resnick Murray B. , Wang Li Juan
Published: January 2017

Routine histopathologic examination of hemorrhoidectomy specimens is controversial having been described as not useful and expensive with few of these common cases demonstrating incidental lesions. However, unexpected premalignant and malignant lesions have been detected on excised hemorrhoids. The high-risk human papillomavirus (HR-HPV) types associated with these incidentally identified high-grade lesions are presently unknown. We aimed to identify cases of incidental high-grade anal intraepithelial neoplasia (HG-AIN) and anal squamous cell carcinoma incidentally discovered on hemorrhoidectomy specimens, genotype HR-HPVs from these lesions, and assess p53 and p16 expression by immunohistochemistry to identify risk factors for their development. With institutional approval, cases with associated demographics from 1995 to 2015 were reviewed to identify and confirm incidental HG-AIN or squamous cell carcinoma in hemorrhoidectomy specimens. Genotyping for HR-HPV types and immunohistochemical staining for p53 and p16 was performed. Statistical analysis comparing HPV genotypes, p53 and p16 staining, and potential risk factors by the Fisher exact test was performed. In the largest series of incidental high-grade lesions on hemorrhoidectomy, HPV 16 was the most common HR-HPV detected though multiple-type infections were common including some HPV 16/18-negative cases. By genotyping, HPV 39 was significantly associated with IV-drug abuse history (P=0.0015) and HIV-positive status (P=0.037), whereas HPV 58 detection correlated with chemotherapy-induced immunosuppression (P=0.029). There was frequent overlap between p53 staining and HPV positivity, particularly when HPV 31 was detected. We also identified several mimickers of HG-AIN that may present diagnostic challenges in these specimens. Our data support continued routine examination of hemorrhoidectomy specimens and suggest that adjunctive studies such as immunohistochemistry for challenging cases may be useful.
Preferential Localization of MET Expression at the Invasion Front and in Spreading Cells Through Air Spaces in Non–Small Cell Lung Carcinomas
Authors: Lapère Camille , Cortot Alexis B. , Grégoire Valérie , Cockenpot Vincent , Tulasne David , Copin Marie-Christine
Published: January 2017

The involvement of the HGF/MET pathway in acquisition of an invasive phenotype in non–small cell lung carcinomas (NSCLCs) suggests that MET inhibitors might prove effective against these cancers, but clinical trials have yielded conflicting results. The aim of our study was to evaluate how intratumoral heterogeneity (ITH) of MET staining affects the determination of MET status for therapeutic purposes. We analyzed 64 NSCLC samples, including 33 adenocarcinomas (ADCs) and 31 squamous cell carcinomas (SCCs). We used immunohistochemistry to detect MET and phospho-MET on whole slides and determined the MET SP44 immunoscore and the H-score. A high METMab score (2+/3+) was observed in 34% of NSCLCs and was more prevalent in ADCs (52%) than in SCCs (16%). We found ITH in 73% of ADCs and 77% of SCCs, with higher levels of MET and phospho-MET at the invasion front (in 52% of ADCs and 22% of SCCs) and in tumor cells spreading through air spaces in ADCs. Within-sample ITH was high in 40% of the ADCs and 29% of the SCCs. When different samples from the same tumor were compared, discordant assessments (high MET vs. low MET) were made for 12% of the ADCs and 10% of the SCCs. C-MET and phospho-MET overexpression occurred preferentially in ADCs and in areas involved in tumor progression, in support of the view that MET activation plays a role in the development of an invasive phenotype in NSCLC. To use MET status adequately as a biomarker, one must take the resulting high level of ITH into account.
Divergent Influences of Cardiovascular Disease Risk Factor Domains on Cognition and Gray and White Matter Morphology
Authors: Gonzales Mitzi M. , Ajilore Olusola , Charlton Rebecca C. , Cohen Jamie , Yang Shaolin , Sieg Erica , Bhaumik Dulal K. , Kumar Anand , Lamar Melissa
Published: January 2017

Objective

Hypertension, diabetes, dyslipidemia, and obesity are associated with preclinical alterations in cognition and brain structure; however, this often comes from studies of comprehensive risk scores or single isolated factors. We examined associations of empirically derived cardiovascular disease risk factor domains with cognition and brain structure.

Methods

A total of 124 adults (age, 59.8 [13.1] years; 41% African American; 50% women) underwent neuropsychological and cardiovascular assessments and structural magnetic resonance imaging. Principal component analysis of nine cardiovascular disease risk factors resulted in a four-component solution representing 1, cholesterol; 2, glucose dysregulation; 3, metabolic dysregulation; and 4, blood pressure. Separate linear regression models for learning, memory, executive functioning, and attention/information processing were performed, with all components entered at once, adjusting for age, sex, and education. MRI analyses included whole-brain cortical thickness and tract-based fractional anisotropy adjusted for age and sex.

Results

Higher blood pressure was associated with poorer learning (B = −0.19; p = .019), memory (B = −0.22; p = .005), and executive functioning performance (B = −0.14; p = .031), and lower cortical thickness within the right lateral occipital lobe. Elevated glucose dysregulation was associated with poorer attention/information processing performance (B = −0.21; p = .006) and lower fractional anisotropy in the right inferior and bilateral superior longitudinal fasciculi. Cholesterol was associated with higher cortical thickness within left caudal middle frontal cortex. Metabolic dysfunction was positively associated with right superior parietal lobe, left inferior parietal lobe, and left precuneus cortical thickness.

Conclusions

Cardiovascular domains were associated with distinct cognitive, gray, and white matter alterations and distinct age groups. Future longitudinal studies may assist in identifying vulnerability profiles that may be most important for individuals with multiple cardiovascular disease risk factors.
Time-course and mechanisms of homeostatic plasticity in layers 2/3 and 5 of the barrel cortex
Authors: Glazewski Stanislaw , Greenhill Stuart , Fox Kevin
Published: January 2017

Recent studies have shown that ocular dominance plasticity in layer 2/3 of the visual cortex exhibits a form of homeostatic plasticity that is related to synaptic scaling and depends on TNFα. In this study, we tested whether a similar form of plasticity was present in layer 2/3 of the barrel cortex and, therefore, whether the mechanism was likely to be a general property of cortical neurons. We found that whisker deprivation could induce homeostatic plasticity in layer 2/3 of barrel cortex, but not in a mouse strain lacking synaptic scaling. The time-course of homeostatic plasticity in layer 2/3 was similar to that of L5 regular spiking (RS) neurons (L5RS), but slower than that of L5 intrinsic bursting (IB) neurons (L5IB). In layer 5, the strength of evoked whisker responses and
ex vivo
miniature excitatory post-synaptic currents (mEPSCs) amplitudes showed an identical time-course for homeostatic plasticity, implying that plasticity at excitatory synapses contacting layer 5 neurons is sufficient to explain the changes in evoked responses. Spontaneous firing rate also showed homeostatic behaviour for L5IB cells, but was absent for L5RS cells over the time-course studied. Spontaneous firing rate homeostasis was found to be independent of evoked response homeostasis suggesting that the two depend on different mechanisms.

This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’.
Functional consequences of pre- and postsynaptic expression of synaptic plasticity
Authors: Costa Rui Ponte , Mizusaki Beatriz E. P. , Sjöström P. Jesper , van Rossum Mark C. W.
Published: January 2017

Growing experimental evidence shows that both homeostatic and Hebbian synaptic plasticity can be expressed presynaptically as well as postsynaptically. In this review, we start by discussing this evidence and methods used to determine expression loci. Next, we discuss the functional consequences of this diversity in pre- and postsynaptic expression of both homeostatic and Hebbian synaptic plasticity. In particular, we explore the functional consequences of a biologically tuned model of pre- and postsynaptically expressed spike-timing-dependent plasticity complemented with postsynaptic homeostatic control. The pre- and postsynaptic expression in this model predicts (i) more reliable receptive fields and sensory perception, (ii) rapid recovery of forgotten information (memory savings), and (iii) reduced response latencies, compared with a model with postsynaptic expression only. Finally, we discuss open questions that will require a considerable research effort to better elucidate how the specific locus of expression of homeostatic and Hebbian plasticity alters synaptic and network computations.

This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’.
Integrating Hebbian and homeostatic plasticity: the current state of the field and future research directions
Authors: Keck Tara , Toyoizumi Taro , Chen Lu , Doiron Brent , Feldman Daniel E. , Fox Kevin , Gerstner Wulfram , Haydon Philip G. , Hübener Mark , Lee Hey-Kyoung , Lisman John E. , Rose Tobias , Sengpiel Frank , Stellwagen David , Stryker Michael P. , Turrigiano Gina G. , van Rossum Mark C.
Published: January 2017

We summarize here the results presented and subsequent discussion from the meeting on Integrating Hebbian and Homeostatic Plasticity at the Royal Society in April 2016. We first outline the major themes and results presented at the meeting. We next provide a synopsis of the outstanding questions that emerged from the discussion at the end of the meeting and finally suggest potential directions of research that we believe are most promising to develop an understanding of how these two forms of plasticity interact to facilitate functional changes in the brain.

This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’.
Enhancement of visual cortex plasticity by dark exposure
Authors: Erchova Irina , Vasalauskaite Asta , Longo Valentina , Sengpiel Frank
Published: January 2017

Dark rearing is known to delay the time course of the critical period for ocular dominance plasticity in the visual cortex. Recent evidence suggests that a period of dark exposure (DE) may enhance or reinstate plasticity even after closure of the critical period, mediated through modification of the excitatory–inhibitory balance and/or removal of structural brakes on plasticity. Here, we investigated the effects of a week of DE on the recovery from a month of monocular deprivation (MD) in the primary visual cortex (V1) of juvenile mice. Optical imaging of intrinsic signals revealed that ocular dominance in V1 of mice that had received DE recovered slightly more quickly than of mice that had not, but the level of recovery after three weeks was similar in both groups. Two-photon calcium imaging showed no significant difference in the recovery of orientation selectivity of excitatory neurons between the two groups. Parvalbumin-positive (PV+) interneurons exhibited a smaller ocular dominance shift during MD but again no differences in subsequent recovery. The percentage of PV+ cells surrounded by perineuronal nets, a structural brake on plasticity, was lower in mice with than those without DE. Overall, DE causes a modest enhancement of mouse visual cortex plasticity.

This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’.
Tumour necrosis factor-mediated homeostatic synaptic plasticity in behavioural models: testing a role in maternal immune activation
Authors: Konefal Sarah C. , Stellwagen David
Published: January 2017

The proinflammatory cytokine tumour necrosis factor-alpha (TNFα) has long been characterized for its role in the innate immune system, but more recently has been found to have a distinct role in the nervous system that does not overlap with other proinflammatory cytokines. Through regulation of neuronal glutamate and GABA receptor trafficking, TNF mediates a homeostatic form of synaptic plasticity, but plays no direct role in Hebbian forms of plasticity. As yet, there is no evidence to suggest that this adaptive plasticity plays a significant role in normal development, but it does maintain neuronal circuit function in the face of several types of disruption. This includes developmental plasticity in primary sensory cortices, as well as modulating the response to antidepressants, chronic antipsychotics and drugs of abuse. TNF is also a prominent component of the neuroinflammation occurring in most neuropathologies, but the role of TNF-mediated synaptic plasticity in this context remains to be determined. We tested this in a maternal immune activation (MIA) model of neurodevelopmental disorders. Using

TNF
−/−

mice, we observed that TNF is not required for the expression of abnormal social or anxious behaviour in this model. This indicates that TNF does not uniquely contribute to the development of neuronal dysfunction in this model, and suggests that during neuroinflammatory events, compensation between the various proinflammatory cytokines is the norm.

This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’.
Glutamatergic synapses are structurally and biochemically complex because of multiple plasticity processes: long-term potentiation, long-term depression, short-term potentiation and scaling
Authors: Lisman John
Published: January 2017

Synapses are complex because they perform multiple functions, including at least six mechanistically different forms of plasticity. Here, I comment on recent developments regarding these processes. (i) Short-term potentiation (STP), a Hebbian process that requires small amounts of synaptic input, appears to make strong contributions to some forms of working memory. (ii) The rules for long-term potentiation (LTP) induction in CA3 have been clarified: induction does not depend obligatorily on backpropagating sodium spikes but, rather, on dendritic branch-specific
N
-methyl-
d
-aspartate (NMDA) spikes. (iii) Late LTP, a process that requires a dopamine signal (and is therefore neoHebbian), is mediated by trans-synaptic growth of the synapse, a growth that occurs about an hour after LTP induction. (iv) LTD processes are complex and include both homosynaptic and heterosynaptic forms. (v) Synaptic scaling produced by changes in activity levels are not primarily cell-autonomous, but rather depend on network activity. (vi) The evidence for distance-dependent scaling along the primary dendrite is firm, and a plausible structural-based mechanism is suggested.

Ideas about the mechanisms of synaptic function need to take into consideration newly emerging data about synaptic structure. Recent super-resolution studies indicate that glutamatergic synapses are modular (module size 70–80 nm), as predicted by theoretical work. Modules are trans-synaptic structures and have high concentrations of postsynaptic density-95 (PSD-95) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor. These modules function as quasi-independent loci of AMPA-mediated transmission and may be independently modifiable, suggesting a new understanding of quantal transmission.

This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity.’
Integrating Hebbian and homeostatic plasticity: introduction
Authors: Fox Kevin , Stryker Michael
Published: January 2017

Hebbian plasticity is widely considered to be the mechanism by which information can be coded and retained in neurons in the brain. Homeostatic plasticity moves the neuron back towards its original state following a perturbation, including perturbations produced by Hebbian plasticity. How then does homeostatic plasticity avoid erasing the Hebbian coded information? To understand how plasticity works in the brain, and therefore to understand learning, memory, sensory adaptation, development and recovery from injury, requires development of a theory of plasticity that integrates both forms of plasticity into a whole. In April 2016, a group of computational and experimental neuroscientists met in London at a discussion meeting hosted by the Royal Society to identify the critical questions in the field and to frame the research agenda for the next steps. Here, we provide a brief introduction to the papers arising from the meeting and highlight some of the themes to have emerged from the discussions.

This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’.
Effects of Altered Excitation-Inhibition Balance on Decision Making in a Cortical Circuit Model
Authors: Lam Norman H. , Borduqui Thiago , Hallak Jaime , Roque Antonio C. , Anticevic Alan , Krystal John H. , Wang Xiao-Jing , Murray John D.
Published: January 2017

Background

Disruption of the synaptic balance between excitation and inhibition (E/I balance) in cortical circuits is a leading hypothesis for pathophysiologies of neuropsychiatric disorders, such as schizophrenia. However, it is poorly understood how synaptic E/I disruptions propagate upward to induce cognitive deficits, including impaired decision making (DM).

Methods

We investigated how E/I perturbations may impair temporal integration of evidence during perceptual DM in a biophysically-based model of association cortical microcircuits. Using multiple psychophysical task paradigms, we characterized effects of NMDA receptor hypofunction at two key synaptic sites: inhibitory interneurons (elevating E/I ratio, via disinhibition), versus excitatory pyramidal neurons (lowering E/I ratio).

Results

Disruption of E/I balance in either direction can similarly impair DM as assessed by psychometric performance, following inverted-U dependence. Nonetheless, these regimes make dissociable predictions for task paradigms that characterize the time course of evidence accumulation. Under elevated E/I ratio, DM is impulsive: evidence early in time is weighted much more than late evidence. In contrast, under lowered E/I ratio, DM is indecisive: evidence integration and winner-take-all competition between options are weakened. These effects are well captured by an extended drift-diffusion model with self-coupling.

Conclusions

Our findings characterize critical roles of cortical E/I balance in cognitive functions, the utility of timing-sensitive psychophysical paradigms, and relationships between circuit and psychological models. The model makes specific predictions for behavior and neural activity that are testable in humans or animals under causal manipulations of E/I balance and in disease states.
Heritability of theSymbiodiniumcommunity in vertically- and horizontally-transmitting broadcast spawning corals
Authors: Quigley Kate , Willis Bette , Bay Line
Published: January 2017

The dinoflagellate-coral partnership influences the coral holobiont’s tolerance to thermal stress and bleaching. However, the comparative roles of host genetic versus environmental factors in determining the composition of this symbiosis are largely unknown. Here we quantify the heritability of the initialSymbiodiniumcommunities for two broadcast-spawning corals with different symbiont transmission modes:Acropora tenuishas environmental acquisition, whereasMontipora digitatahas maternal transmission. Using high throughput sequencing of the ITS-2 region to characterize communities in parents, juveniles and eggs, we describe previously undocumentedSymbiodiniumdiversity and dynamics in both corals. After one month of uptake in the field,Symbiodiniumcommunities associated withA. tenuisjuveniles were dominated by A3, C1, D1, A-type CCMP828, and D1a in proportional abundances conserved between experiments in two years.M. digitataeggs were predominantly characterized by C15, D1, and A3. In contrast to current paradigms, host genetic influences accounted for a surprising 29% of phenotypic variation inSymbiodiniumcommunities in the horizontally-transmittingA. tenuis, but only 62% in the vertically-transmittingM. digitata. Our results reveal hitherto unknown flexibility in the acquisition ofSymbiodiniumcommunities and substantial heritability in both species, providing material for selection to produce partnerships that are locally adapted to changing environmental conditions.
The RAG transposon is active through the deuterostome evolution and domesticated in jawed vertebrates
Authors: Morales Poole Jose Ricardo , Huang Sheng Feng , Xu Anlong , Bayet Justine , Pontarotti Pierre
Published: January 2017

RAG1 and RAG2 are essential subunits of the V(D)J recombinase required for the generation of the variability of antibodies and T-cell receptors in jawed vertebrates. It was demonstrated that the amphioxus homologue of RAG1-RAG2 is encoded in an active transposon, belonging to the transposase DDE superfamily. The data provided supports to the possibility that the RAG transposon has been active through the deuterostome evolution and is still active in several lineages. The RAG transposon corresponds to several families present in deuterostomes. RAG1-RAG2 V(D)J recombinase evolved from one of them, partially due to the new ability of the transposon to interact with the cellular reparation machinery. Considering the fact that the RAG transposon survived millions of years in many different lineages, in multiple copies, and that DDE transposases evolved their association with proteins involved in repair mechanisms, we propose that the apparition of V(D)J recombination machinery could be a predictable genetic event.
Cone-like rhodopsin expressed in the all cone retina of the colubrid pine snake as a potential adaptation to diurnality
Authors: Bhattacharyya Nihar , Darren Benedict , Schott Ryan K. , Tropepe Vincent , Chang Belinda S.W.
Published: January 2017

Colubridae is the largest and most diverse family of snakes, with visual systems that reflect this diversity, encompassing a variety of retinal photoreceptor organizations. The transmutation theory proposed by Walls postulates that photoreceptors could evolutionarily transition between cell types in squamates, but few studies have tested this theory. Recently, evidence for transmutation and rod-like machinery in an all cone retina has been identified in a diurnal garter snake (Thamnophis), and it appears that the rhodopsin gene at least may be widespread among colubrid snakes. However, functional evidence supporting transmutation beyond the existence of the rhodopsin gene remains rare. We examined the all cone retina of another diurnal colubrid,Pituophis melanoleucus, distantly related toThamnophis. We found thatP. melanoleucusexpresses two cone opsins (SWS1, LWS) and rhodopsin (RH1) within the eye. Immunohistochemistry localized rhodopsin to the outer segment of photoreceptors in the all-cone retina of the snake and all opsin genes produced functional visual pigments when expressedin vitro. Consistent with other studies, we found thatP. melanoleucusrhodopsin is extremely blue-shifted. Surprisingly,P. melanoleucusrhodopsin reacted with hydroxylamine, a typical cone opsin characteristic. These results support the idea that the rhodopsin-containing photoreceptors ofP. melanoleucusare the products of evolutionary transmutation from rod ancestors, and suggests that this phenomenon may be widespread in colubrid snakes. We hypothesize that transmutation may be an adaptation for diurnal, brighter-light vision, which could result in increased spectral sensitivity and chromatic discrimination with the potential for colour vision.

Summary Statement

The all cone retina of the colubrid snake,Pituophis melanoleucuscontains a blue-shifted rhodopsin with cone opsin-like properties, which may have been adaptive in diurnal snakes.
catena-Poly[[μ2-4,4′-bis(pyridin-3-ylethynyl)-1,1′-biphenyl-κ2
N:N′]bis(μ2-thiocyanato-κ2
N:S)bis(thiocyanato-κS)dimercury(II)]
Authors: Tan Shuzhi , Liu Leili , Du Yongli
Published: January 2017

In the title polymer, [Hg2(SCN)4(C26H16N2)]
n
, the two equivalent HgII atoms are coordinated by one N atom of a bridging 4,4′-bis(pyridin-3-ylethynyl)-1,1′-biphenyl ligand, two S atoms of two thiocyanates and one N atom of a thiocyanate, giving rise to a distored tetrahedral coordination environment. Two thiocyanate ligands bridge symmetry-related metal atoms to form a polymeric chain extending parallel to [001], and another bridging mode is accomplished by the organic ligand that is located about an inversion centre. The dihedral angle between the coordinating pyridine ring and the benzene ring is 11.4 (2)°, and the two coordinating pyridine rings in the organic ligand are parallel by symmetry. The point group of the ligand in the compound is thus close to C
2h
. The result of the mode of the organic ligands is the formation of zigzag sheets connected via bridging thiocyanate ligands.
Governance structures, voluntary disclosures and public accountability
Authors: Ntim Collins G. , Soobaroyen Teerooven , Broad Martin J.
Published: January 2017

Purpose

The purpose of this paper is to investigate the extent of voluntary disclosures in UK higher education institutions’ (HEIs) annual reports and examine whether internal governance structures influence disclosure in the period following major reform and funding constraints.

Design/methodology/approach

The authors adopt a modified version of Coy and Dixon’s (2004) public accountability index, referred to in this paper as a public accountability and transparency index (PATI), to measure the extent of voluntary disclosures in 130 UK HEIs’ annual reports. Informed by a multi-theoretical framework drawn from public accountability, legitimacy, resource dependence and stakeholder perspectives, the authors propose that the characteristics of governing and executive structures in UK universities influence the extent of their voluntary disclosures.

Findings

The authors find a large degree of variability in the level of voluntary disclosures by universities and an overall relatively low level of PATI (44 per cent), particularly with regards to the disclosure of teaching/research outcomes. The authors also find that audit committee quality, governing board diversity, governor independence and the presence of a governance committee are associated with the level of disclosure. Finally, the authors find that the interaction between executive team characteristics and governance variables enhances the level of voluntary disclosures, thereby providing support for the continued relevance of a “shared” leadership in the HEIs’ sector towards enhancing accountability and transparency in HEIs.

Research limitations/implications

In spite of significant funding cuts, regulatory reforms and competitive challenges, the level of voluntary disclosure by UK HEIs remains low. Whilst the role of selected governance mechanisms and “shared leadership” in improving disclosure, is asserted, the varying level and selective basis of the disclosures across the surveyed HEIs suggest that the public accountability motive is weaker relative to the other motives underpinned by stakeholder, legitimacy and resource dependence perspectives.

Originality/value

This is the first study which explores the association between HEI governance structures, managerial characteristics and the level of disclosure in UK HEIs.
Thermo-mixed lubrication analysis of coated compression rings with worn cylinder profiles
Authors: Zavos Anastasios , Nikolakopoulos Pantelis
Published: January 2017

Purpose

Compression rings are the main sources of frictional losses in internal combustion engines. The present paper aims to present a thermo-mixed hydrodynamic analysis for coated top compression rings. To understand the coating effects, the main tribological parameters are investigated into a ring-cylinder conjunction in a motorbike engine. Furthermore, flow simulations have been carried out on how different worn profiles on the cylinder inner liner affects friction, lubricant film and localized contact deformation of the coated compression rings.

Design/methodology/approach

In this paper, the basic geometrical dimensions of the top compression ring-cylinder system are obtained from a real motorbike engine. A 2D axisymmetric CFD/FLOTRAN model is created for coated compression rings. Flow simulations are performed by solving the Navier-Stokes and the energy equations. The load capacity of the asperities is also taken into account by Greenwood and Tripp contact model. Realistic boundary conditions are imposed to simulate the in-plane ring motion. The simulation model is validated with analytical and experimental data from the literature. Under thermal considerations, the contribution of worn cylinder profiles in conjunction with different coated compression rings is presented.

Findings

This research shows that because of thermal effects, the boundary friction is higher at reversals and the viscous friction is lower because of reduced oil viscosity. As regards to the isothermal case, the viscous friction is greater because of a higher lubricant viscosity. In the case of chromium-plated ring, boundary friction was 16 per cent lower than a grey cast iron ring taking into account thermal effects. Regarding the localized contact deformation, the coated compression rings showed lower values under different worn cylinder shapes. In particular, hard wear-resistant (Ni-Cr-Mo) coating showed the slighter local deformation. Therefore, the worn cylinder profiles promote boundary/mixed lubrication regime, whereas the lobed profile of cylinder inner liner becomes more wavy.

Originality/value

The solution of the thermo-mixed lubrication model, concerning the piston ring and worn cylinder tribo pair by taking into account the coating of the top compression ring.
Improvement of wear behaviour of titanium by boriding
Authors: Kara Gökhan , Purcek Gencaga , Yanar Harun
Published: January 2017

Purpose

The purpose of this paper is to achieve a hard and protective borided layer on commercially pure Ti (grade-2) by applying boriding, and to investigate the changes in its microstructure, hardness, friction and wear behaviors.

Design/methodology/approach

Pack boriding technique was used to form a hard boron diffusion layer on titanium substrate. A powder mixture of amorphous boron and anhydrous borax was used as a solid-state boriding media, and then the boriding was carried out under inert atmosphere.

Findings

A thick dual boride layer consisting of a monolithic titanium diboride (TiB2) on the top and titanium monoboride (TiB) whiskers beneath that layer formed at relatively low diffusion temperature under pressured inert argon atmosphere in a boriding media containing boron source and activator. With boriding at specified conditions, very hard (4100 Hv0.01) and thick monolithic TiB2 layer formed on the top-most layer which is required for improved tribological applications. Hardness decreased gradually through the TiB whisker layer and finally reached to the hardness of base material.

Originality/value

This paper investigates the effects of components of boriding mixture and conditions of thermal treatment on the formation of borided layer and its properties. In previous studies, boriding mixtures containing a boron source, an activator and a filler material was generally used at high temperatures around or above 1,050°C to achieve a thick monolithic layer on the top of the surface of titanium. In the present study, no filler material was used to accelerate the boron diffusion because filler materials may inhibit the diffusion of boron atom through the surface of substrate of titanium. Also, diffusion treatment was carried out under pressurized argon atmosphere at relatively low diffusion temperature to achieve boride layer with the improved hardness and durability.
Military spending, armed conflict and economic growth in developing countries in the post-Cold War era
Authors: Aziz Nusrate , Asadullah M. Niaz
Published: January 2017

Purpose

While the relationship between military expenditure and economic growth during the Cold War period is well-researched, relatively less is known on the issue for the post-Cold War era. Equally how the relationship varies with respect to exposure to conflict is also not fully examined. Therefore, the purpose of this paper is to investigate the causal impact of military expenditure on growth in the presence of internal and external threats for the period 1990-2013 using data from 70 developing countries.

Design/methodology/approach

The main estimates are based on the generalized method of moments (GMM) regression model. But for comparison purposes, the authors also report estimates using fixed and random effects as well as pooled cross-section regressions. The regression specification accounts for non-linear effect of military expenditure allowing for interaction with conflict variable (where distinction is made between external and internal conflict).

Findings

The analysis indicates that methods as well as model specification matter in studying the effect of military spending on growth. Full sample estimates based on GMM, fixed, and random effects models suggest a negative and statistically significant effect of military expenditure. However, fixed effects estimate becomes insignificant for low-income countries. The effect of military spending is also insignificant in the cross-sectional OLS model if conflict is not considered. When the regression model additionally controls for conflict, the effect of military spending conditional upon (internal) conflict exposure is significant and positive. No such effect is present conditional upon external threat.

Research limitations/implications

One important limitation of the analysis is the small sample size – the authors had to restrict analysis to 70 low and middle-income countries for which the authors could construct post-Cold War panel data on military expenditure along with information on armed conflict exposure (the later from the Uppsala Conflict Data Program, 2015).

Originality/value

To the best of the author’s knowledge, this is the first paper to examine the joint impact of military expenditure and conflict on economic growth in post-Cold War period in a sample of developing countries. Moreover, an attempt is made to review and revisit the large Cold War literature where studies vary considerably in terms findings. A key reason for this is the somewhat ad hoc choice of econometric methods – most rely on cross-section data and rarely conduct sensitivity analysis. The authors instead rely on panel data estimates but also report results based on naïve models for comparison purposes.
Relative institutional quality and FDI inflows in ASEAN countries
Authors: Masron Tajul Ariffin
Published: January 2017

Purpose

Foreign direct investment (FDI) inflows into any country, especially ASEAN countries, is affected by any improvement in the institutional quality (IQ) of competitors such as China. As generally investors make decisions by comparing two countries’ IQ, the ratio of two countries’ IQ matters more than a single country’s IQ. The purpose of this paper is to re-examine the role of IQ on FDI inflows in ASEAN countries for the period 1996-2013.

Design/methodology/approach

With limited information on IQ, this study pools eight ASEAN countries as the sample for analysis from 1996 until 2013. A panel dynamic approach – namely, dynamic ordinary least square and fully modified ordinary least square – is utilized.

Findings

This study confirmed that relative IQ significantly affects FDI inflows into ASEAN countries. The low effect is more reflective of the small portion of world FDI inflows into the ASEAN region.

Research limitations/implications

This study observes the crucial relationship between IQ and FDI – that the relative effectiveness of IQ in attracting FDI inflows depends heavily on the changes in both countries’ IQ. Hence, the effort of ASEAN countries to improve IQ and use it as a means to lure FDI inflows should go beyond a mere improvement. Focus should be on significant improvement of IQ so that multinational corporations will comfortably remain or inject new FDI into the country.

Practical implications

Every ASEAN country should double their efforts toward improving their IQ in order to attract future FDI.

Originality/value

Several studies have confirmed the role of IQ on FDI inflows. However, the majority of these studies have investigated the effect of IQ exclusively for a specific country even though some of them have used a panel of several countries’ data. On the other hand, investors normally evaluate their decision on whether or not to invest based on the relative terms, comparing several potential locations of investment at once. This study can be considered the first to explore the potential effect of IQ after taking into account the possibility of each ASEAN country’s IQ being easily offset by changes in the IQ of China.
Stock market development and income inequality
Authors: Tsagkanos Athanasios
Published: January 2017

Purpose

The purpose of this paper, in contrast to other studies, is to examine an indirect relationship in terms of the effect of income inequality with stock market development in countries South of the Euro-zone during the period 2002-2013.

Design/methodology/approach

The author adopts a new econometric method, the Improved Augmented Regression Method, to obtain bias-reduced and stationary-corrected estimators.

Findings

The results reveal a negative relationship that puts into doubt the recovery of growth.

Originality/value

The new econometric methodology leads to a novel suggested policy on the need for reforms adopting a low-income tax rate system and reinforcement of export-oriented productivity. This conclusion is strengthened by the respective relationship in USA.
Ethical team leadership and trainee auditors’ likelihood of reporting client’s irregularities
Authors: Liu Guangyou , Ren Hong
Published: January 2017

Purpose

This paper aims to investigate the impacts of audit engagement team’s ethical leadership, trainee auditors’ reporting intent and other selected factors on their likelihood of reporting client’s irregularities.

Design/methodology/approach

The present investigation is based on 150 effective questionnaire responses provided by a group of trainee auditors working for certified public accounting (CPA) firms. The questionnaire items relating to trainee auditors’ likelihood of reporting client’s irregularities are based on Crawford and Weirich’s (2011) classification of common forms of fraudulent financial reporting. The authors’ measurement of the audit engagement team leaders’ ethicality is based on the ethical leadership scale developed in Newstrom and Ruch (1975) and Kantor and Weisberg (2002). Regression models are used to testify the authors’ hypotheses on the correlations of the trainee auditors’ likelihood of reporting client’s irregularities with audit engagement team’s ethical leadership, trainee auditor’ reporting intents and other selected factors.

Findings

The major conclusion of this study is that there is a significantly positive correlation between trainee auditors’ likelihood of reporting client’s irregularities and their perception of audit engagement team leader’s ethicality. This paper also points out that trainee auditors’ higher evaluation of stable firm–client relationship reduces their likelihood of reporting client’s irregularities, whereas their concerns with future career development increase the likelihood of reporting. In addition, this paper documents the fact that male trainee auditors more easily perceive the ethicality of their team leader than females, and that trainee auditors with less academic achievements (lower GPA) tend to perceive more easily the ethicality of their team leader than those with better academic achievements (higher GPA).

Research limitations/implications

Two business ethics variables constructed and used in this study, i.e. trainee auditors’ likelihood of reporting client’s irregularities and engagement team leader’s ethicality, can be applied in future research on whistleblowing in the audit profession.

Practical implications

Practical implications can also be drawn from the findings to enhance the ethical management at both engagement and firm levels.

Originality/value

This paper contributes to the audit research literature by providing evidence on the significant positive impacts of team leader’s ethicality on the entry-level audit professional’s likelihood of reporting client’s irregularities.
An analysis of the Australian illicit tobacco market
Authors: Lauchs Mark , Keane Rebecca
Published: January 2017

Purpose

This paper aims to provide an overview of the illicit tobacco market in Australia. It attempts to build a picture of the sources of demand, size of the market and methods of supply.

Design/methodology/approach

This paper is based on collation of disparate government reports, industry research, media and court documents. It is a preliminary paper in the absence of better source data.

Findings

The market is driven by the extremely high tax on tobacco in Australia. Australia’s geography emphasises on large shipments from overseas rather than small-scale smuggling. The likely market is for migrant communities with much higher smoker rates than in the mainstream community.

Research limitations/implications

It is not yet possible to conduct a well-focused research because of limited official documentation.

Practical implications

Few government agencies focus on tobacco smuggling, and there are no publications providing a strategic picture of the illicit market. This paper fills this gap by collating multiple sources to produce a market profile.

Social implications

The Australian Government loses $1bn per year in tobacco tax because of smuggling. The illicit supply also means that the social goal of the tax, namely, dissuading tobacco consumption, is undermined.

Originality/value

There are no academic or government publications describing the Australian illicit tobacco market. The only publications are based on research funded by the tobacco industry, which has a vested interest in overstating the size of the illicit market.
Procedural changes in Switzerland: the lawyer goes into the interrogation room
Authors: Courvoisier Julie
Published: January 2017

Purpose

The purpose of this paper is to highlight how police officers, lawyers and prosecutors experienced the implementation of the mandatory presence of a lawyer during police interrogation since 2011 in Switzerland.

Design/methodology/approach

This research is based on semi-structured interviews conducted with these practitioners in order to expose their points of view regarding this novelty.

Findings

The presence of a lawyer during interrogation allows for a proper protection of the defendant’s rights. Even if this new collaboration between police and lawyers goes better than expected, some issues still remain. Lawyers can be helpful in some cases, but they also can be considered as an obstacle, especially for psychological aspects and the building of a relationship between police officers and suspects. The issue of videotaped interrogations seems to be currently important in Switzerland and most of these practitioners see this practice as potentially beneficial.

Practical implications

Police interrogation and the question of the defendant’s rights is often mediated, in particular by addressing the issue of false confessions. Knowing the advantages and drawbacks of having a lawyer during interrogation and how everyone experiences the practice can allow to adjust and to improve this new collaboration.

Originality/value

The case of Switzerland with the presence of a lawyer during police interrogations is quite special. Understanding how it works and also compared to videotaping is highly relevant not only for practitioners in criminal justice system.