Sign-reversal of the in-plane resistivity anisotropy in hole-doped iron pnictides

The in-plane anisotropy of the electrical resistivity across the coupled orthorhombic and magnetic transitions of the iron pnictides has been extensively studied in the parent and electron-doped compounds. All these studies universally show that the resistivity $\rho_{a}$ across the long orthorhombic axis $a_{O}$ - along which the spins couple antiferromagnetically below the magnetic transition temperature - is smaller than the resistivity $\rho_{b}$ of the short orthorhombic axis $b_{O}$, i. e. $\rho_{a}<\rho_{b}$. Here we report that in the hole-doped compounds Ba$_{1-x}$K$_{x}$Fe$_{2}$As$_{2}$, as the doping level increases, the resistivity anisotropy initially becomes vanishingly small, and eventually changes sign for sufficiently large doping, i. e. $\rho_{b}<\rho_{a}$. This observation is in agreement with a recent theoretical prediction that considers the anisotropic scattering of electrons by spin-fluctuations in the orthorhombic/nematic state.Comment: This paper has been replaced by the new version offering new explanation of the experimental results first reported her

Buttressing staples with cholecyst-derived extracellular matrix (CEM) reinforces staple lines in an ex vivo peristaltic inflation model

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ Springer Science + Business Media, LLC 2008Background - Staple line leakage and bleeding are the most common problems associated with the use of surgical staplers for gastrointestinal resection and anastomotic procedures. These complications can be reduced by reinforcing the staple lines with buttressing materials. The current study reports the potential use of cholecyst-derived extracellular matrix (CEM) in non-crosslinked (NCEM) and crosslinked (XCEM) forms, and compares their mechanical performance with clinically available buttress materials [small intestinal submucosa (SIS) and bovine pericardium (BP)] in an ex vivo small intestine model. Methods - Three crosslinked CEM variants (XCEM0005, XCEM001, and XCEM0033) with different degree of crosslinking were produced. An ex vivo peristaltic inflation model was established. Porcine small intestine segments were stapled on one end, using buttressed or non-buttressed surgical staplers. The opened, non-stapled ends were connected to a peristaltic pump and pressure transducer and sealed. The staple lines were then exposed to increased intraluminal pressure in a peristaltic manner. Both the leak and burst pressures of the test specimens were recorded. Results - The leak pressures observed for non-crosslinked NCEM (137.8 ± 22.3 mmHg), crosslinked XCEM0005 (109.1 ± 14.1 mmHg), XCEM001 (150.1 ± 16.0 mmHg), XCEM0033 (98.8 ± 10.5 mmHg) reinforced staple lines were significantly higher when compared to non-buttressed control (28.3 ± 10.8 mmHg) and SIS (one and four layers) (62.6 ± 11.8 and 57.6 ± 12.3 mmHg, respectively) buttressed staple lines. NCEM and XCEM were comparable to that observed for BP buttressed staple lines (138.8 ± 3.6 mmHg). Only specimens with reinforced staple lines were able to achieve high intraluminal pressures (ruptured at the intestinal mesentery), indicating that buttress reinforcements were able to withstand pressure higher than that of natural tissue (physiological failure). Conclusions - These findings suggest that the use of CEM and XCEM as buttressing materials is associated with reinforced staple lines and increased leak pressures when compared to non-buttressed staple lines. CEM and XCEM were found to perform comparably with clinically available buttress materials in this ex vivo model.Enterprise Irelan

Overvaluation of shape and weight in adolescents with anorexia nervosa: does shape concern or weight concern matter more for treatment outcome?

BACKGROUND: Overvaluation of shape and weight is a key diagnostic feature of anorexia nervosa (AN); however, limited research has evaluated the clinical utility of differentiating between weight versus shape concerns. Understanding differences in these constructs may have important implications for AN treatment given the focus on weight regain. This study examined differences in treatment outcome between individuals whose primary concern was weight versus those whose primary concern was shape in a randomized controlled trial of treatment for adolescent AN. METHODS: Data were drawn from a two-site randomized controlled trial that compared family-based treatment and adolescent focused therapy for AN. Chi-square tests and logistic regression analyses were conducted. RESULTS: Thirty percent of participants presented with primary weight concern (n = 36; defined as endorsing higher Eating Disorder Examination (EDE) Weight Concern than Shape Concern subscale scores); 60 % presented with primary shape concern (n = 72; defined as endorsing higher EDE Shape Concern than Weight Concern scores). There were no significant differences between the two groups in remission status at the end of treatment. Treatment did not moderate the effect of group status on achieving remission. CONCLUSIONS: Results suggest that treatment outcomes are comparable between adolescents who enter treatment for AN with greater weight concerns and those who enter treatment with greater shape concerns. Therefore, treatment need not be adjusted based on primary weight or primary shape concerns

Visceral hyperalgesia induced by forebrain-specific suppression of native Kv7/KCNQ/M-current in mice

<p>Abstract</p> <p>Background</p> <p>Dysfunction of brain-gut interaction is thought to underlie visceral hypersensitivity which causes unexplained abdominal pain syndromes. However, the mechanism by which alteration of brain function in the brain-gut axis influences the perception of visceral pain remains largely elusive. In this study we investigated whether altered brain activity can generate visceral hyperalgesia.</p> <p>Results</p> <p>Using a forebrain specific αCaMKII promoter, we established a line of transgenic (Tg) mice expressing a dominant-negative pore mutant of the Kv7.2/KCNQ2 channel which suppresses native KCNQ/M-current and enhances forebrain neuronal excitability. Brain slice recording of hippocampal pyramidal neurons from these Tg mice confirmed the presence of hyperexcitable properties with increased firing. Behavioral evaluation of Tg mice exhibited increased sensitivity to visceral pain induced by intraperitoneal (i.p.) injection of either acetic acid or magnesium sulfate, and intracolon capsaicin stimulation, but not cutaneous sensation for thermal or inflammatory pain. Immunohistological staining showed increased c-Fos expression in the somatosensory SII cortex and insular cortex of Tg mice that were injected intraperitoneally with acetic acid. To mimic the effect of cortical hyperexcitability on visceral hyperalgesia, we injected KCNQ/M channel blocker XE991 into the lateral ventricle of wild type (WT) mice. Intracerebroventricular injection of XE991 resulted in increased writhes of WT mice induced by acetic acid, and this effect was reversed by co-injection of the channel opener retigabine.</p> <p>Conclusions</p> <p>Our findings provide evidence that forebrain hyperexcitability confers visceral hyperalgesia, and suppression of central hyperexcitability by activation of KCNQ/M-channel function may provide a therapeutic potential for treatment of abdominal pain syndromes.</p

Elite or middling? International students and migrant diversification

Student migrants from former sending regions now form a substantial share of non-European Union migration flows to Europe. These flows represent the convergence of extensive internationalisation of higher education with increasing restrictions on family and labour migration. This article provides the first examination of student migrants? early socio-cultural and structural integration by following recently arrived Pakistani students in London over an 18-month period. We use latent class analysis to identify both elite and two ?middling? types ? middle class and network-driven ? within our student sample. We then ask whether these types experience early socio-cultural and structural integration trajectories that differ in the ways that the elite and middling transnational literatures would suggest. We find differences in structural, but less in socio-cultural outcomes. We conclude that to understand the implications of expanding third country student migration across the European Union, it is important to recognize both the distinctiveness of this flow and its heterogeneity

Prevalence and clinical characteristics of serum neuronal cell surface antibodies in first-episode psychosis: a case-control study

$\textbf{Background}$ Psychosis is a common presenting feature in antibody-mediated encephalitis, for which prompt recognition and treatment usually leads to remission. We aimed to investigate whether people with circumscribed schizophrenia-like illnesses have such antibodies—especially antibodies against the N-methyl-D-aspartate receptor (NMDAR)—more commonly than do healthy controls. $\textbf{Methods}$ We recruited patients aged 14–35 years presenting to any of 35 mental health services sites across England with first-episode psychosis, less than 6 weeks of treatment with antipsychotic medication, and a score of 4 or more on at least one selected Positive and Negative Syndrome Scale (PANSS) item. Patients and controls provided venous blood samples. We completed standardised symptom rating scales (PANSS, ACE-III, GAF) at baseline, and tested serum samples for antibodies against NMDAR, LGI1, CASPR2, the GABAA receptor, and the AMPA receptor using live cell-based assays. Treating clinicians assessed outcomes of ICD diagnosis and functioning (GAF) at 6 months. We included healthy controls from the general population, recruited as part of another study in Cambridge, UK. $\textbf{Findings}$ Between Feb 1, 2013, and Aug 31, 2014, we enrolled 228 patients with first-episode psychosis and 105 healthy controls. 20 (9%) of 228 patients had serum antibodies against one or more of the neuronal cell surface antibodies compared with four (4%) of 105 controls (unadjusted odds ratio 2·4, 95% CI 0·8–7·3). These associations remained non-significant when adjusted for current cigarette smoking, alcohol consumption, and illicit drug use. Seven (3%) patients had NMDAR antibodies compared with no controls (p=0·0204). The other antibodies did not differ between groups. Antibody-positive patients had lower PANSS positive, PANSS total, and catatonia scores than did antibody-negative patients. Patients had comparable scores on other PANSS items, ACE-III, and GAF at baseline, with no difference in outcomes at 6 months. $\textbf{Interpretation}$ Some patients with first-episode psychosis had antibodies against NMDAR that might be relevant to their illness, but did not differ from patients without NMDAR antibodies in clinical characteristics. Our study suggests that the only way to detect patients with these potentially pathogenic antibodies is to screen all patients with first-episode psychosis at first presentation.Medical Research Counci

Complementary methods to investigate the development of clogging within a horizontal sub-surface flow tertiary treatment wetland

A combination of experimental methods was applied at a clogged, horizontal subsurface flow (HSSF) municipal wastewater tertiary treatment wetland (TW) in the UK, to quantify the extent of surface and subsurface clogging which had resulted in undesirable surface flow. The three dimensional hydraulic conductivity profile was determined, using a purpose made device which recreates the constant head permeameter test in-situ. The hydrodynamic pathways were investigated by performing dye tracing tests with Rhodamine WT and a novel multi-channel, data-logging, flow through Fluorimeter which allows synchronous measurements to be taken from a matrix of sampling points. Hydraulic conductivity varied in all planes, with the lowest measurement of 0.1 md1 corresponding to the surface layer at the inlet, and the maximum measurement of 1550 md1 located at a 0.4m depth at the outlet. According to dye tracing results, the region where the overland flow ceased received five times the average flow, which then vertically short-circuited below the rhizosphere. The tracer break-through curve obtained from the outlet showed that this preferential flow-path accounted for approximately 80% of the flow overall and arrived 8 h before a distinctly separate secondary flow-path. The overall volumetric efficiencyof the clogged system was 71% and the hydrology was simulated using a dual-path, dead-zone storage model. It is concluded that uneven inlet distribution, continuous surface loading and high rhizosphere resistance is responsible for the clog formation observed in this system. The average inlet hydraulic conductivity was 2 md1, suggesting that current European design guidelines, which predict that the system will reach an equilibrium hydraulic conductivity of 86 md1, do not adequately describe the hydrology of mature systems

Cholinergic afferent stimulation induces axonal function plasticity in adult hippocampal granule cells.

Acetylcholine critically influences hippocampal-dependent learning. Cholinergic fibers innervate hippocampal neuron axons, dendrites, and somata. The effects of acetylcholine on axonal information processing, though, remain unknown. By stimulating cholinergic fibers and making electrophysiological recordings from hippocampal dentate gyrus granule cells, we show that synaptically released acetylcholine preferentially lowered the action potential threshold, enhancing intrinsic excitability and synaptic potential-spike coupling. These effects persisted for at least 30 min after the stimulation paradigm and were due to muscarinic receptor activation. This caused sustained elevation of axonal intracellular Ca(2+) via T-type Ca(2+) channels, as indicated by two-photon imaging. The enhanced Ca(2+) levels inhibited an axonal KV7/M current, decreasing the spike threshold. In support, immunohistochemistry revealed muscarinic M1 receptor, CaV3.2, and KV7.2/7.3 subunit localization in granule cell axons. Since alterations in axonal signaling affect neuronal firing patterns and neurotransmitter release, this is an unreported cellular mechanism by which acetylcholine might, at least partly, enhance cognitive processing

Exploring the current and future role of the pharmacists in osteoporosis screening and management in Malaysia

Background Several studies have found that pharmacists can assist in screening and prevention of osteoporosis by referring patients for bone mineral density scans and counselling on lifestyle changes. In Malaysia, screening osteoporosis in all elderly women is not mandatory due to its cost. One approach to address this gap is to develop a pharmacist-led osteoporosis screening and prevention program. However, there is a paucity of data on the perspectives of Malaysian pharmacists in this area. Objective To explore the perspective of stakeholders (policy makers, doctors, pharmacists, nurses and patients) towards the role of pharmacists in osteoporosis screening and management. Setting A primary care clinic located within a teaching hospital in Kuala Lumpur, Malaysia. Method Patients (n = 20), nurses (n = 10), pharmacists (n = 11), doctors (n = 10) and policy makers (n = 5) were individually interviewed using a semi-structured topic guide. Purposive sampling was used. Interviews were transcribed verbatim and analysed using thematic analysis. Main outcome measure Perspective of stakeholders on the current and future role of pharmacists. Results All participants perceived pharmacists to be suppliers of medication, although there was some recognition of roles in providing medication advice. Nonetheless, these stakeholders were eager for pharmacists to expand their non-dispensing roles towards counselling, creating awareness and screening of osteoporosis. Interviewed pharmacists referred to their current role as ‘robotic dispensers’ and unanimously agreed to spread out to osteoporosis management role. Conclusion Under stakeholders there is a willingness to expand the role of pharmacists in Malaysia to non-dispensing roles, particularly in osteoporosis screening and management