Symmetric improved estimators for multipoint vertex functions

Multipoint vertex functions, and the four-point vertex in particular, are crucial ingredients in many-body theory. Recent years have seen significant algorithmic progress toward numerically computing their dependence on multiple frequency arguments. However, such computations remain challenging and are prone to suffer from numerical artifacts, especially in the real-frequency domain. Here, we derive estimators for multipoint vertices that are numerically more robust than those previously available. We show that the two central steps for extracting vertices from correlators, namely the subtraction of disconnected contributions and the amputation of external legs, can be achieved accurately through repeated application of equations of motion, in a manner that is symmetric with respect to all frequency arguments and involves only fully renormalized objects. The symmetric estimators express the core part of the vertex and all asymptotic contributions through separate expressions that can be computed independently, without subtracting the large-frequency limits of various terms with different asymptotic behaviors. Our strategy is general and applies equally to the Matsubara formalism, the real-frequency zero-temperature formalism, and the Keldysh formalism. We demonstrate the advantages of the symmetric improved estimators by computing the Keldysh four-point vertex of the single-impurity Anderson model using the numerical renormalization group.Comment: 35 pages, 23 figure

Comparative Analysis of Efficiency of Injection Laryngoplasty Technique for with or without Neck Treatment Patients: A Transcartilaginous Approach Versus the Cricothyroid Approach

ObjectivesThese days, the main injection laryngoplasty technique is cricothyroid (CT) approach. However, patients who have previously undergone other neck treatments, such as thyroidectomy or neck dissection have distorted anatomical landmark makes this approach more difficult. The aim of this study is to determined the efficiency of transcartilaginous (TC) approah as compared with CT approach for unilateral vocal fold paralysis patients, especially for previously neck treated patients.MethodsFrom March 2005 to February 2008, 137 consecutive injection laryngoplasties were performed in patients with unilateral glottic insufficiency. Percutaneous injection was performed under local anesthesia into the vocalis muscle, using disposable 25 G 4 cm long needles through the cricothyroid membrane or directly through the thyroid cartilage. Of the 137 patients, 124 completed acoustic, perceptual, stroboscopic, and subjective evaluations prior to the injection and at 3 months after the injection.ResultsIn the 124 patients, the CT and TC approaches were used in 94 and 30 patients, respectively. Acoustic and perceptual parameters (GRBAS, MPT, jitter, shimmer), voice handicap index, and grades of mucosal waves and glottic closure were significantly improved after the injection in both the CT and TC groups (P<0.05). Only two patients (6.6%) had penetration difficulties, because of ossification of the thyroid cartilage. The overall success rates of the CT and TC approaches were 86.2%, 93.3%, respectively. However, the success rate of the TC approach in patients who had previously undergone neck treatments was significantly higher than that of the CT approach (100% vs. 65% P<0.05).ConclusionBased on the preliminary results of this trial, injection laryngoplasty using a TC approach was an effective alternative to the CT approach, especially in patients who had previously undergone neck surgeries

Optimal target blood pressure for the primary prevention of hemorrhagic stroke: a nationwide observational study

BackgroundThere are few reports on the preventative value of intensive blood pressure (BP) management for stroke, especially hemorrhagic stroke (HS), after new criteria for hypertension (HTN) were announced by the American College of Cardiology/American Heart Association in 2017.AimsThis study aimed to identify the optimal BP for the primary prevention of HS in a healthy population aged between 20 and 65 years.MethodsWe conducted a 10-year observational study on the risk of HS, subclassified as intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH) according to BP categories (e.g., low normal BP, high normal BP, elevated BP, stage 1 HTN, and stage 2 HTN) using the National Health Insurance Service Database.ResultsOut of 8,327,751 participants who underwent a health checkup in 2008, 949,550 were included in this study and observed from 2009 to 2018. The risk of ICH was significantly increased in men with stage 2 HTN {adjusted hazard ratio [aHR] 2.002 [95% confidence interval (CI) 1.203–3.332]} and in women with stage 1 HTN [aHR 2.021 (95% CI, 1.251–3.263)]. The risk of SAH was significantly increased in both men [aHR 1.637 (95% CI, 1.066–2.514)] and women [aHR 4.217 (95% CI, 2.648–6.715)] with stage 1 HTN. Additionally, the risk of HS was significantly increased in men with stage 2 HTN [aHR 3.034 (95% CI, 2.161–4.260)] and in women with stage 1 HTN [aHR 2.976 (95% CI, 2.222–3.986)].ConclusionTo prevent primary HS, including ICH and SAH, BP management is recommended for adults under the age of 65 years with stage 1 HTN

Three Cases of Non-Surgical Treatment of Stent Loss During Percutaneous Coronary Intervention

Percutaneous coronary intervention with stenting is widely used for ischemic heart disease. Because stent loss, which occurs rarely during the procedure, might have dire consequences, such as bleeding, stent embolism, acute myocardial infarction, emergency coronary artery bypass graft, and death, appropriate treatment is needed as soon as stent loss occurs. We report three cases of stent loss which were successfully treated with three different non-surgical methods

A Case Report of Carbon Monoxide Poisoning Induced Cardiomyopathy Complicated with Left Ventricular Thrombus

The heart and the brain, most oxygen-dependent organs, may be severely affected after carbon monoxide (CO) exposure. CO induced cardiotoxicity may occur as a consequence of moderate to severe CO poisoning, including angina attack, myocardial infarct, arrhythmias, and heart failure. We present a rare case of CO poisoning induced cardiomyopathy with left ventricular (LV) thrombus. It is thought that LV thrombus may have been caused severely decreased LV function with dyskinesis. After short-term anticoagulant therapy, echocardiography findings revealed complete recovery of LV dyskinesis and resolution of LV thrombus

The Interval Between Initiation of Anti-tuberculosis Treatment in Patients with Culture-positive Pulmonary Tuberculosis and Receipt of Drug-susceptibility Test Results

Although mycobacterial culture and the subsequent drug-susceptibility test (DST) for anti-tuberculosis (TB) drugs take several months to complete using solid media, there are no reports on the turnaround times of these tests under clinical conditions. The aim of this study was to determine the interval between initiation of anti-TB treatment and receipt of DST requested at an outpatient clinic. We prospectively enrolled patients with culture-positive pulmonary TB at Seoul National University Hospital from September 2002 to December 2004. Patients were followed up monthly. Mycobacterial cultures were done using Ogawa media at Seoul National University Hospital. DST were performed at the Korean Institute of Tuberculosis. Of the 104 patients enrolled, 54 were male. The median age was 41 yr. The median interval from initiation of anti-TB treatment to receipt of mycobacterial culture results by clinicians was 37 days (range, 0-89 days). The median interval from initiation of treatment to confirmation of DST by requesting clinicians was 80.5 days (range, 28-145 days). Clinicians only received the results of DST more than two months after initiation of treatment when they followed up patients monthly and mycobacterial culture was performed using solid media

Bladder Recovery by Stem Cell Based Cell Therapy in the Bladder Dysfunction Induced by Spinal Cord Injury: Systematic Review and Meta-Analysis

Background Bladder dysfunction induced by spinal cord injury (SCI) can become problematic and severely impair the quality of life. Preclinical studies of spinal cord injury have largely focused on the recovery of limb function while neglecting to investigate bladder recovery. Objective The present study was performed to investigate and review the effect of stem cell-based cell therapy on bladder recovery in SCI. Methods We conducted a meta-analysis of urodynamic findings of experimental trials that included studies of stem cell-based cell therapy in SCI. Relevant studies were searched using MEDLINE, EMBASE and Cochrane Library (January 1990 -December 2012). Final inclusion was determined by a urodynamic study involving detailed numerical values. Urodynamic parameters for analysis included voiding pressure, residual urine, bladder capacity and non-voiding contraction (NVC). Meta-analysis of the data, including findings from urodynamic studies, was performed using the Mantel-Haenszel method. Results A total of eight studies were included with a sample size of 224 subjects. The studies were divided into different subgroups by different models of SCI. After a stem cell-based cell therapy, voiding pressure (-6.35, p < 0.00001, I-2 = 77%), NVC (-3.58, p < 0.00001, I-2 = 82%), residual urine (-024, p = 0.004, I-2 = 95%) showed overall significant improvement. Bladder capacity showed improvement after treatment only in the transection type (-0.23, p = 0.0002, I-2 = 0%). Conclusion After stem cell-based cell therapy in SCI, partial bladder recovery including improvement of voiding pressure, NVC, and residual urine was demonstrated. Additional studies are needed to confirm the detailed mechanism and to obtain an ideal treatment strategy for bladder recovery.open1156sciescopu