8,231 research outputs found

    Quantum phase excitations in Ginzburg-Landau superconductors

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    We give a straightforward generalization of the Ginzburg-Landau theory for superconductors where the scalar phase field is replaced by an antisymmetric Kalb-Ramond field. We predict that at very low temperatures, where quantum phase effects are expected to play a significant role, the presence of vortices destroys superconductivity.Comment: revtex, 4 pages, no figure

    Treatment of esophageal achalasia in children: Today and tomorrow

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    Esophageal achalasia (EA) is a rare esophageal motility disorder in children. Laparoscopic Heller myotomy (LHM) represents the treatment of choice in young patients. Peroral endoscopic myotomy (POEM) is becoming an alternative to LHM. The aim of this study is to evaluate the effectiveness, safety, and outcomes of POEM vs LHM in treatment of children with EA. Data of pediatric patients with EA, who underwent LHM and POEM from February 2009 to December 2013 in two centers, were collected. Eighteen patients (9 male, mean age: 11.6 years; range: 2-17 years) were included. Nine patients (6 male, mean age: 10.7 years; range: 2-16 years) underwent LHM, and the other 9 (3 males, mean age: 12.2 years; range: 6-17 years) underwent POEM procedure. Mean operation time was shorter in POEM group compared with LHM group (62/149 minutes). Myotomy was longer in POEM group than in LHM group (11/7 cm). One major complication occurred after LHM (esophageal perforation). No clinical and manometric differences were observed between LHM and POEM in follow-up. The incidence of iatrogenic gastroesophageal reflux disease was low (1 patient in both groups). Results of a midterm follow-up show that LHM and POEM are safe and effective treatments also in children. Besides, POEM is a mini-invasive technique with an inferior execution timing compared to LHM. A skilled endoscopic team is mandatory to perform this procedur

    A CT Study of Coronary Arteries in Adult Mustard Patients

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    Acute inflammatory response in the subcutaneous versus periprosthethic space after incisional hernia repair: an original article

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    BACKGROUND: The acute inflammatory response following mesh implantation has been often evaluated in vitro and in animal models. The aim of this study was to evaluate the acute inflammatory response near the prosthesis in human by analysing some inflammatory indicators.METHODS: We used a cohort of twelve male patients affected by midline incisional hernia, who were admitted for surgical mesh repair. A suction drain was placed between the mesh and rectal muscles whereas, the other one was placed between the subcutaneous tissue and the oblique external sheath. The acute inflammatory response was analyzed by measuring the production of interleukin [IL]-1, IL-10, IL-1ra, C-Reactive Protein (CRP), total proteins, albumin and pH in the drain fluids.RESULTS: The dynamics of CRP and ILs production resulted similar in both drainages. Comparing drain over mesh and subcutaneous drain at all times, IL-1 and CRP values always resulted significantly higher in the first one, whereas IL-1ra and IL-10 values were significantly higher in the last one. Total protein and albumin were similar in both drains at all time; only in the drain over mesh fluid, pH values resulted significantly reduced in the fourth post-operative day.CONCLUSIONS: Our data showed that an acute inflammatory reaction is present in both sites examined. However, it was significantly higher in the space after mesh implantation

    FLARES: an aging aware algorithm to autonomously adapt the error correction capability in NAND Flash memories

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    With the advent of solid-state storage systems, NAND flash memories are becoming a key storage technology. However, they suffer from serious reliability and endurance issues during the operating lifetime that can be handled by the use of appropriate error correction codes (ECC) in order to reconstruct the information when needed.. Adaptable ECCs may provide the flexibility to avoid worst-case reliability design thus leading to improved performance. However, a way to control such adaptable ECCs strength is required. This paper proposes FLARES, an algorithm able to adapt the ECC correction capability of each page of a flash based on a flash RBER prediction model and on a measurement of the number of errors detected in a given time window. FLARES has been fully implemented within the YAFFS 2 filesystem under the Linux operating system. This allowed us to perform an extensive set of simulations on a set of standard benchmarks that highlighted the benefit of FLARES on the overall storage subsystem performance

    Levetiracetam in patients with epilepsy and chronic liver disease: observations in a case series.

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    OBJECTIVES: To evaluate levetiracetam (LEV) tolerability in patients with epilepsy and liver disease. METHODS: Fourteen patients with epilepsy and concomitant liver disease were treated with LEV in an open prospective investigation mimicking the daily clinical practice. All patients were stabilized (ie, for at least 1 year) on traditional antiepileptic drugs with complete or partial control of seizures. In the 6-month pre-LEV baseline period, seizure frequency ranged from 3 to 300. Levetiracetam was added on to the basal treatment at a starting daily dose of 250 mg, and the dose was adjusted according to the tolerability and the therapeutic response. Four patients discontinued the drug within the first 3 months because of intolerable side effects. The remaining 10 continued LEV treatment, and the present follow-up is 12 to 38 months. RESULTS: In the last 6 months of observation, none of the patients showed worsening of liver function on the basis of blood chemistry, and in 4 patients, a complete normalization or a trend toward physiological values of transaminase and/or gamma-glutamyltransferase activity was observed. A greater than 50% reduction in seizure frequency occurred in all uncontrolled patients, 2 of whom achieved seizure freedom during LEV treatment. CONCLUSIONS: Based on these observations, LEV seems to be an attractive therapeutic option in epileptic patients with chronic liver diseases

    Concomitant Small Cell Neuroendocrine Carcinoma of Gallbladder and Breast Cancer

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    The neuroendocrine carcinoma is defined as a high-grade malignant neuroendocrine neoplasm arising from enterochromaffin cells, usually disposed in the mucosa of gastric and respiratory tracts. The localization in the gallbladder is rare. Knowledge of these gallbladder tumors is limited and based on isolated case reports. We describe a case of an incidental finding of small cell neuroendocrine carcinoma of the gallbladder, observed after cholecystectomy for cholelithiasis, in a 55-year-old female, who already underwent quadrantectomy and sentinel lymph-node biopsy for breast cancer. The patient underwent radiotherapy for breast cancer and six cycles of chemotherapy with cisplatin and etoposide. Eighteen months after surgery, the patient was free from disease. Small cell neuroendocrine carcinoma of the gallbladder has poor prognosis. Because of the rarity of the reported cases, specific prognostic factors have not been identified. The coexistence of small cell neuroendocrine carcinoma of the gallbladder with another malignancy has been reported only once.The contemporary presence of the two neoplasms could reflect that bioactive agents secreted by carcinoid can promote phenotypic changes in susceptible cells and induce neoplastic transformation

    Atrial fibrillation impairs the diagnostic performance of cardiac natriuretic peptides in dyspneic patients. results from the BACH Study (Biomarkers in ACute Heart Failure)

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    Objectives: The purpose of this study was to assess the impact of atrial fibrillation (AF) on the performance of mid-region amino terminal pro-atrial natriuretic peptide (MR-proANP) in comparison with the B-type peptides (BNP and NT-proBNP) for diagnosis of acute heart failure (HF) in dyspneic patients. Background: The effects of AF on the diagnostic and prognostic performance of MR-proANP in comparison with the B type natriuretic peptides have not been previously reported. Methods: A total of 1,445 patients attending the emergency department with acute dyspnea had measurements taken of MR-proANP, BNP, and NT-proBNP values on enrollment to the BACH trial and were grouped according to presence or absence of AF and HF. Results: AF was present in 242 patients. Plasma concentrations of all three peptides were lowest in those with neither AF nor HF and AF without HF was associated with markedly increased levels (p < 0.00001). HF with or without AF was associated with a significant further increment (p < 0.00001 for all three markers). Areas under receiver operator characteristic curves (AUCs) for discrimination of acute HF were similar and powerful for all peptides without AF (0.893 to 0.912; all p < 0.001) with substantial and similar reductions (0.701 to 0.757) in the presence of AF. All 3 peptides were independently prognostic but there was no interaction between any peptide and AF for prediction of all-cause mortality. Conclusions: AF is associated with increased plasma natriuretic peptide (MR-proANP, BNP and NT-proBNP) levels in the absence of HF. The diagnostic performance of all three peptides is impaired by AF. This warrants consideration of adjusted peptide thresholds for diagnostic use in AF and mandates the continued search for markers free of confounding by AF

    The role of the emergency department in the management of acute heart failure: an international perspective on education and research

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    Emergency departments are a major entry point for the initial management of acute heart failure (AHF) patients throughout the world. The initial diagnosis, management and disposition - the decision to admit or discharge - of AHF patients in the emergency department has significant downstream implications. Misdiagnosis, under or overtreatment, or inappropriate admission may place patients at increased risk for adverse events, and add costs to the healthcare system. Despite the critical importance of initial management, data are sparse regarding the impact of early AHF treatment delivered in the emergency department compared to inpatient or chronic heart failure management. Unfortunately, outcomes remain poor, with nearly a third of patients dying or re-hospitalised within 3 months post-discharge. In the absence of robust research evidence, consensus is an important source of guidance for AHF care. Thus, we convened an international group of practising emergency physicians, cardiologists and advanced practice nurses with the following goals to improve outcomes for AHF patients who present to the emergency department or other acute care setting through: (a) a better understanding of the pathophysiology, presentation and management of the initial phase of AHF care; (b) improving initial management by addressing knowledge gaps between best practices and current practice through education and research; and (c) to establish a framework for future emergency department-based international education and research
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