Testing the nonlinearity of the BVIcJHKs period-luminosity relations for the Large Magellanic Cloud Cepheids

A number of recent works have suggested that the period-luminosity (PL) relation for the Large Magellanic Cloud (LMC) Cepheids exhibits a controversial nonlinear feature with a break period at 10 days. Therefore, the aim of this Research Note is to test the linearity/nonlinearity of the PL relations for the LMC Cepheids in BVIcJHKs band, as well as in the Wesenheit functions. We show that simply comparing the long and short period slopes, together with their associate d standard deviations, leads to a strictly larger error rate than applying rigorous statistical tests such as the F-test. We applied various statistical tests to the current published LMC Cepheid data. These statistical tests include the F-test, the testimator test, and the Schwarz information criterion (SIC) method. The results from these statistical tests strongly suggest that the LMC PL relation is nonlinear in BVIcJH band but linear in the Ks band and in the Wesenheit functions. Using the properties of period-color relations at maximum light and multi-phase relations, we believe that the nonlinear PL relation is not caused by extinction errors.Comment: 6 pages, 5 figures and 2 tables, A&A accepte

Clinical profile,etiology of diarrhoea >2weeks duration in children between 1 month-12years

Aim: The aim of the study is to determine the Clinical profile, Etiology of diarrhoea >2weeks duration in children between 1mon-12yrsof age in tertiary centrein South India Objective: To find the common causes of chronic diarrhoea in our hospital and to findout the most useful methods for diagnosis Introduction: Chronic diarrhoea defined as diarrhoea lasting for more than 14 days. The epidemiology has two distinct patterns: In developing countries persistence of infection either gut or extra gut,malnutrition associated diarrhoea, where as in developed countries chronic diarrhoea is less frequent and the aetiology often varies with age.The outcome of diarrhoea depends on the cause and ranges from benignself-limited to severe congenital disease,that may lead to progressive intestinal failure Study justification: Chronic childhood diarrhoea had variety of etiologies, a specific diagnosis could be established in 90% of cases, by various diagnostic tests, so that appropriate therapy can be instituted to reduce morbidity and mortality. Methodology (Materials& methods) 1.Study design: Prospective Study 2.Study population:Children in study age group attending gastroenterology department and admitted in medical ward, satisfying the inclusion criteria. 3.Place of study: Department of gastroenterology and paediatric medical ward in ICH 4.Study period: October 2016 to September 2017 5.Sample size: 43 6.Inclusion criteria: All children aged 1 month to 12years presenting with diarrhoea >2 weeks attending the hospital 7.Exclusion criteria:children with established diagnosis treatment Procedure: After obtaining informed consent from parent/guardian, various patient demographic characteristics, history, clinical details,anthropometry, will be entered in a pre structured Proforma. All these children will have basic investigations like CBC, peripheral smear, Blood sugar,RFT, Sr.electrolytes,Urine routine, X ray chest,USG,HIV,stool routine and second line investigations include upper GI endoscopy,barium contrast studies &colonoscopy for cases suspected to have tuberculosis, Inflammatory bowel disease. Sigmoidoscopy and biopsy in case of Cow`s milk protein allergy. Statistical Analysis: Data will be entered in excel sheet. Statistical analysis of data will be performed by statistical software SPSS. Outcome variables will be categorized as normal or abnormal and their prevalence will be expressed as percentage and p value of <0.05 will be considered significant. Results: In this study age wise distributionof chronic diarrhoea results were: 21 children (48.8%) aged < 1yr, 17 children(39.5%) aged between 1- 5 yrs and 5 children (11.7%) belongs to more than 5 yrs Mean age of onset of diarrhoea in our study were 23 months ranging from 1 month to 120 months Malnutrition distribution of our study were 62.7% .Of which 16 children had severe acute malnutrition (37.2%), 8 children had moderate acute malnutrition (18.5%), and 3 children aged above 5 yrs with severe underweight (7%). Etiological Results of this study were, intestinal infections(25.58%), Cows milk protein allergy(20.93%),Inflammatory bowel disease (4.65%), congenital zinc deficiency (2.33%), congenital tufting enteropathy (2.33%), intestinal lymphangiectasia (2.33%), malabsorbtion (2.33%), secondary lactose intolerance(2.33%), severe combined immunodeficiency(2.33%) and idiopathic (34.88%) In this study out of 43 children, 42 (97.7%) children were improved with treatment and 1(2.3%) child was died(severe combined immunodeficiency). Conclusion 1. Mean age of onset of chronic diarrhoea in this study was 23 months ranging from 1month -120 months. 2. Most common age group affected in this study was < 1yr of age (48.8%). 3. Male children were more commonly affected (58.1%) than female children (41.9%). Male /female ratio were 1.4:1. 4. Rural children (79.1%) are more commonly affected than Urban (20.9%) children. 5. 5.Small bowel diarrhoea (72.1%) were more common than Large bowel diarrhoea (27.9%). 6. In our study Malnutrition were observed in 62.7% children 7. Commonest cause of chronic diarrhoea in our study was intestinal Infections (25.58%), followed by cow’s milk protein allergy(20.93%). 8. Outcome: Children improved with treatment were (97.7%). One child (2.3%) was died (SCID

Investigations of the Non-Linear LMC Cepheid Period-Luminosity Relation with Testimator and Schwarz Information Criterion Methods

In this paper, we investigate the linearity versus non-linearity of the Large Magellanic Cloud (LMC) Cepheid period-luminosity (P-L) relation using two statistical approaches not previously applied to this problem: the testimator method and the Schwarz Information Criterion (SIC). The testimator method is extended to multiple stages for the first time, shown to be unbiased and the variance of the estimated slope can be proved to be smaller than the standard slope estimated from linear regression theory. The Schwarz Information Criterion (also known as the Bayesian Information Criterion) is more conservative than the Akaike Information Criterion and tends to choose lower order models. By using simulated data sets, we verify that these statistical techniques can be used to detect intrinsically linear and/or non-linear P-L relations. These methods are then applied to independent LMC Cepheid data sets from the OGLE project and the MACHO project, respectively. Our results imply that there is a change of slope in longer period ranges for all of the data sets. This strongly supports previous results, obtained from independent statistical tests, that the observed LMC P-L relation is non-linear with a break period at/around 10 days.Comment: 9 pages, 5 figures and 3 tables, PASP accepte

Multiphysics Analysis of a Magnetorheological Damper

&nbsp; &nbsp; &nbsp;A Magnetorheological damping has evolved as a potential tool in vibration control. The design of magnetorheological damping involves analysis of fluid flow principles and electromagnetic flux analysis. This research paper involves design and analysis of a magnetorheological damper employed for vibration control. The analysis is carried over by considering the domain as an axisymmetric model. The damping force of the damper depends upon the shear stress due to fluid viscosity and yield stress induced due to magnetic flux applied. The damping force generated by the damper is calculated

Exploring the cause of conduction delays in patients with repaired Tetralogy of Fallot

Aim Cardiac dyssynchrony in patients with repaired Tetralogy of Fallot (rToF) has been attributed to right bundle branch block (RBBB), fibrosis and/or the patches that are inserted during repair surgery. We aimed to investigate the basis of abnormal activation in rToF patients by mapping the electrical activation sequence during sinus rhythm (SR) and right ventricular (RV) pacing.Methods and Results A total of 17 patients were studied [13 with rToF, 2 with left bundle branch block (LBBB), and 2 without RBBB or LBBB (non-BBB)] during medically indicated cardiac surgery. During SR and RV pacing, measurements were performed using 112-electrode RV endocardial balloons (rToF only) and biventricular epicardial sock arrays (four of the rToF and all non-rToF patients). During SR, functional lines of block occurred in five rToF patients, while RV pacing caused functional blocks in four rToF patients. The line of block persisted during both SR and RV pacing in only 2 out of 13 rToF patients. Compared to SR, RV pacing increased dispersion of septal activation, but not dispersion of endocardial and epicardial activation of the RV free wall. During pacing, RV and left ventricular activation dispersion in rToF patients were comparable to that of the non-rToF patients.Conclusion The results of the present study indicate that the delayed activation in the right ventricle of rToF patients is predominantly due to block(s) in the Purkinje system and that conduction in RV tissue is fairly normal

Exploration of a potent PI3 kinase/mTOR inhibitor as a novel anti-fibrotic agent in IPF

© 2016 BMJ Publishing Group Ltd & British Thoracic Society.Rationale Idiopathic pulmonary fibrosis (IPF) is the most rapidly progressive and fatal of all fibrotic conditions with no curative therapies. Common pathomechanisms between IPF and cancer are increasingly recognised, including dysfunctional pan-PI3 kinase (PI3K) signalling as a driver of aberrant proliferative responses. GSK2126458 is a novel, potent, PI3K/mammalian target of rapamycin (mTOR) inhibitor which has recently completed phase I trials in the oncology setting. Our aim was to establish a scientific and dosing framework for PI3K inhibition with this agent in IPF at a clinically developable dose. Methods We explored evidence for pathway signalling in IPF lung tissue and examined the potency of GSK2126458 in fibroblast functional assays and precision-cut IPF lung tissue. We further explored the potential of IPF patient-derived bronchoalveolar lavage (BAL) cells to serve as pharmacodynamic biosensors to monitor GSK2126458 target engagement within the lung. Results We provide evidence for PI3K pathway activation in fibrotic foci, the cardinal lesions in IPF. GSK2126458 inhibited PI3K signalling and functional responses in IPF-derived lung fibroblasts, inhibiting Akt phosphorylation in IPF lung tissue and BAL derived cells with comparable potency. Integration of these data with GSK2126458 pharmacokinetic data from clinical trials in cancer enabled modelling of an optimal dosing regimen for patients with IPF. Conclusions Our data define PI3K as a promising therapeutic target in IPF and provide a scientific and dosing framework for progressing GSK2126458 to clinical testing in this disease setting. A proof-ofmechanism trial of this agent is currently underway. Trial registration number NCT01725139, pre-clinical

Converse Flexoelectricity of Low-Dimensional Bismuth Selenite (Bi2Se3) Revealed by Piezoresponse Force Microscopy (PFM)

Many kinds of two-dimensional (2D) van der Waals (vdW) have been demonstrated to exhibit electromechanical coupling effects, which makes them promising candidates for next-generation devices, such as piezotronics and nanogenerators. Recently, flexoelectricity was found to account for the out-of-plane electromechanical coupling in many 2D transition metal dichalcogenides (TMDs) who only exhibit in-plane piezoelectricity. However, low dimensional vdW three-dimensional (3D) topological insulators (TIs) have been overlooked regarding their electromechanical properties. In this study, for the first time, we experimentally investigate the electromechanical coupling of low dimensional 3D TIs with a centrosymmetric crystal structure, where a binary compound, bismuth selenite (Bi2Se3), is taken as an example. The results of piezoresponse force microscope (PFM) tests on the Bi2Se3 nanoflakes show that the material exhibits both out-of-plane and in-plane electromechanical responses. The Bi2Se3 nanoflake with a thickness of 37 nm possesses an effective out-of-plane piezoelectric coefficient of ~0.65 pm V-1. With careful analyses, the electromechanical responses are verified to arise from the converse flexoelectricity. The measured effective out-of-plane piezoelectric coefficient is mainly contributed by flexoelectric coefficient, {\mu}_39, which is estimated to be approximately 0.13 nC m-1. However, it is rather difficult to obtain the in-plane component of the flexoelectric tensor from the in-plane PFM measurements since the direction of the in-plane stress is always not normal to the AFM cantilever axis. The results provide useful guidance for understanding the flexoelectric effect of low dimensional vdW materials with centrosymmetric crystal structures. Moreover, the work can pave to way to explore the electromechanical devices based on the flexoelectricity of vdW TIs.Comment: 6 figure

Bipolar ablation for deep intra-myocardial circuits: human ex vivo development and in vivo experience.

To access publisher's full text version of this article click on the hyperlink at the bottom of the pageCurrent conventional ablation strategies for ventricular tachycardia (VT) aim to interrupt reentrant circuits by creating ablation lesions. However, the critical components of reentrant VT circuits may be located at deep intramural sites. We hypothesized that bipolar ablations would create deeper lesions than unipolar ablation in human hearts.Ablation was performed on nine explanted human hearts at the time of transplantation. Following explant, the hearts were perfused by using a Langendorff perfusion setup. For bipolar ablation, the endocardial catheter was connected to the generator as the active electrode and the epicardial catheter as the return electrode. Unipolar ablation was performed at 50 W with irrigation of 25 mL/min, with temperature limit of 50°C. Bipolar ablation was performed with the same settings. Subsequently, in a patient with an incessant septal VT, catheters were positioned on the septum from both the ventricles and radiofrequency was delivered with 40 W. In the explanted hearts, there were a total of nine unipolar ablations and four bipolar ablations. The lesion depth was greater with bipolar ablation, 14.8 vs. 6.1 mm (P < 0.01), but the width was not different (9.8 vs. 7.8 mm). All bipolar lesions achieved transmurality in contrast to the unipolar ablations. In the patient with a septal focus, bipolar ablation resulted in termination of VT with no inducible VTs.By using a bipolar ablation technique, we have demonstrated the creation of significantly deeper lesions without increasing the lesion width, compared with standard ablation. Further clinical trials are warranted to detail the risks of this technique

Biomarkers of collagen synthesis predict progression in the PROFILE idiopathic pulmonary fibrosis cohort.

Idiopathic pulmonary fibrosis (IPF) is characterised by excessive extracellular matrix (ECM) deposition and remodelling. Measuring this activity provides an opportunity to develop tools capable of identifying individuals at-risk of progression. Longitudinal change in markers of ECM synthesis was assessed in 145 newly-diagnosed individuals with IPF. Serum levels of collagen synthesis neoepitopes, PRO-C3 and PRO-C6 (collagen type 3 and 6), were elevated in IPF compared with controls at baseline, and progressive disease versus stable disease during follow up, (PRO-C3 p  0 vs. LOW slope, slope < =0) demonstrated no relationship with mortality for these markers (PRO-C3 (HR 1.62, p = 0.080); PINP (HR 0.76, p = 0.309); PRO-C6 (HR 1.14, p = 0.628)). As previously reported, rising concentrations of collagen degradation markers C1M, C3M, C6M and CRPM were associated with an increased risk of overall mortality (HR = 1.84, CI 1.03–3.27, p = 0.038, HR = 2.44, CI 1.39–4.31, p = 0.002; HR = 2.19, CI 1.25–3.82, p = 0.006; HR = 2.13 CI 1.21–3.75, p = 0.009 respectively). Elevated levels of PRO-C3 and PRO-C6 associate with IPF disease progression. Collagen synthesis and degradation biomarkers have the potential to enhance clinical trials in IPF and may inform prognostic assessment and therapeutic decision making in the clinic