Order in a Spatially Anisotropic Triangular Antiferromagnet

The phase diagram of the spin-1/2 Heisenberg antiferromagnet on an anisotropic triangular lattice of weakly coupled chains, a model relevant to Cs2CuCl4, is investigated using a renormalization group analysis, which includes marginal couplings important for connecting to numerical studies of this model. In particular, the relative stability of incommensurate spiral spin-density order and collinear antiferromagnetic order is studied. While incommensurate spiral order is found to exist over most of the phase diagram in the presence of a Dzyaloshinskii-Moriya (DM) interaction, at small interchain and extremely weak DM couplings, collinear antiferromagnetic order can survive. Our results imply that Cs2CuCl4 is well within the part of the phase diagram where spiral order is stable. The implications of the renormalization group analysis for numerical studies, many of which have found spin-liquidlike behavior, are discussed.Comment: 10 pages, 7 figures, minor edits and reference adde

The issue of ventral versus dorsal approach in bulbar urethral reconstruction

No abstract

Omega-3 polyunsaturated fatty acid supplementation versus placebo on vascular health, glycaemic control, and metabolic parameters in people with type 1 diabetes: a randomised controlled preliminary trial

Background: The role of omega-3 polyunsaturated fatty acids (n-3PUFA), and the potential impact of n-3PUFA supplementation, in the treatment and management of type 1 diabetes (T1D) remains unclear and controversial. Therefore, this study aimed to examine the efficacy of daily high-dose-bolus n-3PUFA supplementation on vascular health, glycaemic control, and metabolic parameters in subjects with T1D. Methods: Twenty-seven adults with T1D were recruited to a 6-month randomised, double-blind, placebo-controlled trial. Subjects received either 3.3 g/day of encapsulated n-3PUFA or encapsulated 3.0 g/day corn oil placebo (PLA) for 6-months, with follow-up at 9-months after 3-month washout. Erythrocyte fatty acid composition was determined via gas chromatography. Endpoints included inflammation-associated endothelial biomarkers (vascular cell adhesion molecule-1 [VCAM-1], intercellular adhesion molecule-1 [ICAM-1], E-selectin, P-selectin, pentraxin-3, vascular endothelial growth factor [VEGF]), and their mediator tumor necrosis factor alpha [TNFα] analysed via immunoassay, vascular structure (carotid intima-media thickness [CIMT]) and function (brachial artery flow mediated dilation [FMD]) determined via ultrasound technique, blood pressure, glycosylated haemoglobin (HbA1c), fasting plasma glucose (FPG), and postprandial metabolism. Results: Twenty subjects completed the trial in full. In the n-3PUFA group, the mean ± SD baseline n-3PUFA index of 4.93 ± 0.94% increased to 7.67 ± 1.86% (P  0.05). Conclusions: This study indicates that daily high-dose-bolus of n-3PUFA supplementation for 6-months does not improve vascular health, glucose homeostasis, or metabolic parameters in subjects with T1D. The findings from this preliminary RCT do not support the use of therapeutic n-3PUFA supplementation in the treatment and management of T1D and its associated complications. Trial Registration ISRCTN, ISRCTN40811115. Registered 27 June 2017, http://www.isrctn.com/ISRCTN40811115

Enhancement of Robust Tracking Performance via Switching Supervisory Adaptive Control

When the process is highly uncertain, even linear minimum phase systems must sacrifice desirable feedback control benefits to avoid an excessive ‘cost of feedback’, while preserving the robust stability. In this paper, the problem of supervisory based switching Quantitative Feedback Theory (QFT) control is proposed for the control of highly uncertain plants. According to this strategy, the uncertainty region is suitably divided into smaller regions. It is assumed that a QFT controller-prefilter exits for robust stability and performance of the individual uncertain sets. The proposed control architecture is made up by these local controllers, which commute among themselves in accordance with the decision of a high level decision maker called the supervisor. The supervisor makes the decision by comparing the candidate local model behavior with the one of the plant and selects the controller corresponding to the best fitted model. A hysteresis switching logic is used to slow down switching for stability reasons. Besides, each controller is designed to be stable in the whole uncertainty domain, and as accurate in command tracking as desired in its uncertainty subset to preserve the robust stability from any failure in the switching

Male urethral strictures : a national survey among urologists in Italy

Objective To determine national practice patterns in the management of male urethral strictures among Italian urologists. Methods We conducted a survey using a nonvalidated questionnaire mailed to 700 randomly selected Italian urologists. Data were registered into a database and extensively evaluated. Analysis was performed using SAS statistical software (version 9.2). Statistical significance was defined as P 64.05. Results A total of 523 (74.7%) urologists completed the questionnaire. Internal urethrotomy and dilatation were the most frequently used procedures (practiced by 81.8% and 62.5% of responders, respectively), even if most urologists (71.5%) considered internal urethrotomy appropriate only for strictures no longer than 1.5 cm; 12% of urologists declared to use stents. Overall, minimally invasive techniques were performed more frequently that any open urethroplasty (P =.012). Particularly, 60.8% of urologists did not perform urethroplasty surgery, 30.8% performed 1-5 urethroplasties yearly, and only 8.4% performed >5 urethroplasty surgeries yearly. The most common urethroplasty surgery was one-stage graft technique, particularly using oral mucosa and ventrally placed. Diagnostic workup and outcome assessment varied greatly. Conclusion In Italy, minimally invasive procedures are the most commonly used treatment for urethral stricture disease. Only a minimal part of urologists perform urethroplasty surgery and only few cases per year. The most preferred techniques are not traditional anastomotic procedures but graft urethroplasties using oral mucosa; the graft is preferably ventrally placed rather than dorsally. There is no uniformity in the methods used to evaluate urethral stricture before and after treatment

Male urethral strictures: a national survey among urologists in Italy

OBJECTIVE: To determine national practice patterns in the management of male urethral strictures among Italian urologists. METHODS: We conducted a survey using a nonvalidated questionnaire mailed to 700 randomly selected Italian urologists. Data were registered into a database and extensively evaluated. Analysis was performed using SAS statistical software (version 9.2). Statistical significance was defined as P ≤.05. RESULTS: A total of 523 (74.7%) urologists completed the questionnaire. Internal urethrotomy and dilatation were the most frequently used procedures (practiced by 81.8% and 62.5% of responders, respectively), even if most urologists (71.5%) considered internal urethrotomy appropriate only for strictures no longer than 1.5 cm; 12% of urologists declared to use stents. Overall, minimally invasive techniques were performed more frequently that any open urethroplasty (P = .012). Particularly, 60.8% of urologists did not perform urethroplasty surgery, 30.8% performed 1-5 urethroplasties yearly, and only 8.4% performed >5 urethroplasty surgeries yearly. The most common urethroplasty surgery was one-stage graft technique, particularly using oral mucosa and ventrally placed. Diagnostic workup and outcome assessment varied greatly. CONCLUSION: In Italy, minimally invasive procedures are the most commonly used treatment for urethral stricture disease. Only a minimal part of urologists perform urethroplasty surgery and only few cases per year. The most preferred techniques are not traditional anastomotic procedures but graft urethroplasties using oral mucosa; the graft is preferably ventrally placed rather than dorsally. There is no uniformity in the methods used to evaluate urethral stricture before and after treatment