Modeling of liquid flow in surface discontinuities

Polymer composite and metallic materials have found wide application in various industries such as aviation, rocket, car manufacturing, ship manufacturing, etc. Many design elements need permanent quality control. Ensuring high quality and reliability of products is impossible without effective nondestructive testing methods. One of these methods is penetrant testing using penetrating substances based on liquid penetration into defect cavities. In this paper, we propose a model of liquid flow to determine the rates of filling the defect cavities with various materials and, based on this, to choose optimal control modes

Major histocompatibility complex class I molecules protect motor neurons from astrocyte-induced toxicity in amyotrophic lateral sclerosis

Astrocytes isolated from individuals with amyotrophic lateral sclerosis (ALS) are toxic to motor neurons (MNs) and play a non–cell autonomous role in disease pathogenesis. The mechanisms underlying the susceptibility of MNs to cell death remain unclear. Here we report that astrocytes derived from either mice bearing mutations in genes associated with ALS or human subjects with ALS reduce the expression of major histocompatibility complex class I (MHCI) molecules on MNs; reduced MHCI expression makes these MNs susceptible to astrocyte-induced cell death. Increasing MHCI expression on MNs increases survival and motor performance in a mouse model of ALS and protects MNs against astrocyte toxicity. Overexpression of a single MHCI molecule, HLA-F, protects human MNs from ALS astrocyte–mediated toxicity, whereas knockdown of its receptor, the killer cell immunoglobulin-like receptor KIR3DL2, on human astrocytes results in enhanced MN death. Thus, our data indicate that, in ALS, loss of MHCI expression on MNs renders them more vulnerable to astrocyte-mediated toxicity

Volatility in the Housing Market: Evidence on Risk and Return in the London Sub-market

The impact of volatility in housing market analysis is reconsidered via examination of the risk-return relationship in the London housing market is examined. In addition to providing the first empirical results for the relationship between risk (as measured by volatility) and returns for this submarket, the analysis offers a more general message to empiricists via a detailed and explicit evaluation of the impact of empirical design decisions upon inferences. In particular, the negative risk-return relationship discussed frequently in the housing market literature is examined and shown to depend upon typically overlooked decisions concerning components of the empirical framework from which statistical inferences are drawn

Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012

2017 HRS/EHRA/ECAS/APHRS/SOLAECE expert consensus statement on catheter and surgical ablation of atrial fibrillation: executive summary.

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Clinical features of infantile hepatic hemangioendothelioma

PurposeInfantile hepatic hemangioendothelioma (IHHE) is the most common type of hepatic vascular tumor in infancy. We conducted this study to review our clinical experience of patients with IHHE and to suggest management strategies.MethodsWe retrospectively analyzed the medical records of 23 IHHE patients (10 males, 13 females) treated at the Asan Medical Center between 1996 and 2009.ResultsMedian age at diagnosis was 38 days (range, 1 to 381 days). Seven patients (30%) were diagnosed with IHHE based on sonographically detected fetal liver masses, 5 (22%) were diagnosed incidentally in the absence of symptoms, 5 (22%) had congestive heart failure, 3 (13%) had skin hemangiomas, 2 (9%) had abnormal liver function tests, and 1 (4%) had hepatomegaly. All diagnoses were based on imaging results, and were confirmed in three patients by histopathology analysis. Six patients were observed without receiving any treatment, whereas 12 received corticosteroids and/or interferon-alpha. One patient with congestive heart failure and a resectable unilobar tumor underwent surgical resection. Three patients with congestive heart failure and unresectable tumors were managed by hepatic artery embolization with/without medical treatment. At a median follow-up of 29 months (range, 1 to 156 months), 21 (91%) patients showed complete tumor disappearance or >50% decrease in tumor size. One patient died due to tumor-related causes.ConclusionIHHE generally has a benign clinical course with low morbidity and mortality rates. Clinical course and treatment outcome did not differ significantly between medically treated and non-treated groups. Surgically unresectable patients with significant symptoms may be treated medically or with hepatic artery embolization

An unusual clinical presentation resembling superior vena cava syndrome post heart surgery

BACKGROUND: An unusual sequence of post operative events heralded by hemodynamic deterioration followed by dyspnea and rapidly progressive dilatation of superficial neck and facial veins, resembling a superior vena cava syndrome, two days post surgical resection of filamentous aortic valve masses, closure of a patent foramen ovale, and performance of a modified Maze procedure for atrial fibrillation in a patient that presented with transient neurologic findings is presented. CASE PRESENTATION: Although both clinical findings and hemodynamic derangements completely resolved following tricuspid valve repair aimed to correct the new onset severe tricuspid regurgitation noted post operatively; a clear mechanism was not readily obvious and diagnostic testing data somewhat conflictive. We present a careful retrospective examination of all clinical data and review possible clinical entities that could have been implicated in this particular case and recognize that transesophageal echocardiographic findings were most useful in identifying the best course of action. CONCLUSION: After reviewing all clinical data and despite the inconclusive nature of test results; the retrospective examination of transesophageal echocardiographic findings proved to be most useful in identifying the best course of action. We postulate that in our case, resolution of the suspected pulmonary embolism with anticoagulation and reestablishment of a normal right ventricular geometry with tricuspid valve repair worked in unison in restoring normal hemodynamics and resolving both dyspnea and venous dilatation

Why can pulmonary vein stenoses created by radiofrequency catheter ablation worsen during and after follow-up ? A potential explanation

<p>Abstract</p> <p>Background</p> <p>Radiofrequency catheter ablation of excitation foci inside pulmonary veins (PV) generates stenoses that can become quite severe during or after the follow-up period. Since severe PV stenoses have most often disastrous consequences, it would be important to know the underlying mechanism of this temporal evolution. The present study proposes a potential explanation based on mechanical considerations.</p> <p>Methods</p> <p>we have used a mathematical-physical model to examine the cyclic increase in axial wall stress induced in the proximal (= upstream), non-stenosed segment of a stenosed pulmonary vein during the forward flow phases. In a representative example, the value of this increase at peak flow was calculated for diameter stenoses (DS) ranging from 1 to 99%.</p> <p>Results</p> <p>The increase becomes appreciable at a DS of roughly 30% and rise then strongly with further increasing DS value. At high DS values (e.g. > 90%) the increase is approximately twice the value of the axial stress present in the PV during the zero-flow phase.</p> <p>Conclusion</p> <p>Since abnormal wall stresses are known to induce damages and abnormal biological processes (e.g., endothelium tears, elastic membrane fragmentations, matrix secretion, myofibroblast generation, etc) in the vessel wall, it seems plausible that the supplementary axial stress experienced cyclically by the stenotic and the proximal segments of the PV is responsible for the often observed progressive reduction of the vessel lumen after healing of the ablation injury. In the light of this model, the only potentially effective therapy in these cases would be to reduce the DS as strongly as possible. This implies most probably stenting or surgery.</p

Pulmonary Complications After Hematopoietic Stem Cell Transplantation

Despite advanced effective prophylaxes, pulmonary complications still occur in a high proportion of all hematopoietic stem cell recipients, accounting for considerable morbidity and mortality. The aim of our study was to describe the causes, incidences and mortality rates secondary to pulmonary complications and risk factors of such complications following hematopoietic stem cell transplantation (HSCT). We reviewed the medical records of 287 patients who underwent either autologous or allogeneic HSCT for hematologic disorders from February 1996 to October 2003 at Samsung Medical Center (134 autografts, 153 allografts). The timing of pulmonary complications was divided into pre-engraftment, early and late period. The spectrum of pulmonary complications included infectious and non-infectious conditions. 73 of the 287 patients (25.4%) developed pulmonary complications. Among these patients, 40 (54.8%) and 29 (39.7%) had infectious and non-infectious conditions, respectively. The overall mortality rate from pulmonary complications was 28.8%. Allogeneic transplant, grade II-IV acute graft-versus-host disease (GVHD) and extensive chronic GVHD were the risk factors with statistical significance for pulmonary complications after HSCT. The mortality rates from pulmonary complications following HSCT were high, especially those of viral and fungal pneumonia, diffuse alveolar hemorrhage and idiopathic pneumonia syndrome

Inhibition of IFN-γ-dependent antiviral airway epithelial defense by cigarette smoke

<p>Abstract</p> <p>Background</p> <p>Although individuals exposed to cigarette smoke are more susceptible to respiratory infection, the effects of cigarette smoke on lung defense are incompletely understood. Because airway epithelial cell responses to type II interferon (IFN) are critical in regulation of defense against many respiratory viral infections, we hypothesized that cigarette smoke has inhibitory effects on IFN-γ-dependent antiviral mechanisms in epithelial cells in the airway.</p> <p>Methods</p> <p>Primary human tracheobronchial epithelial cells were first treated with cigarette smoke extract (CSE) followed by exposure to both CSE and IFN-γ. Epithelial cell cytotoxicity and IFN-γ-induced signaling, gene expression, and antiviral effects against respiratory syncytial virus (RSV) were tested without and with CSE exposure.</p> <p>Results</p> <p>CSE inhibited IFN-γ-dependent gene expression in airway epithelial cells, and these effects were not due to cell loss or cytotoxicity. CSE markedly inhibited IFN-γ-induced Stat1 phosphorylation, indicating that CSE altered type II interferon signal transduction and providing a mechanism for CSE effects. A period of CSE exposure combined with an interval of epithelial cell exposure to both CSE and IFN-γ was required to inhibit IFN-γ-induced cell signaling. CSE also decreased the inhibitory effect of IFN-γ on RSV mRNA and protein expression, confirming effects on viral infection. CSE effects on IFN-γ-induced Stat1 activation, antiviral protein expression, and inhibition of RSV infection were decreased by glutathione augmentation of epithelial cells using N-acetylcysteine or glutathione monoethyl ester, providing one strategy to alter cigarette smoke effects.</p> <p>Conclusions</p> <p>The results indicate that CSE inhibits the antiviral effects of IFN-γ, thereby presenting one explanation for increased susceptibility to respiratory viral infection in individuals exposed to cigarette smoke.</p