28 research outputs found
Effect of strong magnetic field on the first-order electroweak phase transition
The broken-symmetry electroweak vacuum is destabilized in the presence of a
magnetic field stronger than a critical value. Such magnetic field may be
generated in the phase transition and restore the symmetry inside the bubbles.
A numerical calculation indicates that the first-order phase transition is
delayed but may be completed for a sufficient low value of the Higgs mass
unless the magnetic field is extremely high.Comment: 7 pages including 2 figures, uses epsf.sty; discussion regarding
cosmological consequences (e.g. on baryogenesis) enlarged, some references
added and a few misprints correcte
Assessment of the numerical diffusion effect in the advection of a passive tracer in BOLCHEM
The effects of the numericalsc heme implemented in the advection equation of BOLCHEM have been quantified with reference to the diffusion of a passive tracer. An equivalent horizontal diffusion coefficient has been measured and is found to be dependent on wind field and resolution
Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study
Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk
Higgs boson masses in a non-minimal supersymmetric model
A study of the neutral Higgs spectrum in a general Z sub 3 -breaking Next to Minimal Supersymmetric Standard Model (NMSSM) is reported in several significant contexts. Particular attention has been devoted to the upper bound on lightest Higgs boson. In the CP-conserving case we show that the extra terms involved in the general Z sub 3 -breaking superpotential do not affect the upper bound which remains unchanged: it is approx 136 GeV when tan beta = 2.7. The Spontaneous CP Violation scenario in the Z sub 3 -breaking NMSSM can occur at tree-level. When the phases of the fields are small the spectrum shows the lightest Higgs particle to be an almost singlet CP-odd. The second lightest particle, a doublet almost-CP-even state, still manifests the upper bound of the CP-conserving case. When the CP-violating phases are large the lightest particle is a doublet with no definite CP parity and its mass shows the usual upper bound at approx 136 GeV. The large number of parameters involved in the effective potential can be significantly reduced in the Infrared Quasi Fixed Point (IRQFP) resulting after solving the Renormalization Group (RG) equations assuming universality for the soft SUSY breaking masses. In the Z sub 3 -breaking NMSSM, unlike the Z sub 3 -conserving NMSSM, it is possible to find a Higgs spectrum which is still compatible with both experiment and universality at the unification scale. Because in the IRQFP regime tan beta approx 1.8 and the stop mixing parameter is reduced then the upper bound on the lightest Higgs boson turns out to be approx 121 GeV. This result is compatible with experimental data coming from LEPII and might be one of the next predictions to be tested at hadron collider experiments
SESSUALITÀ ED EMOZIONI: STUDIO SULL'ASSOCIAZIONE TRA ALESSITIMIA E DISFUNZIONE ERETTILE (DE)
Modified “pluck” technique with Tissucol for the management of distal ureter during nephroureterectomy
Introduction & Objectives: Nephroureterectomy is a well established technique for managing the upper urinary tract urothelial carcinoma (UTCC). However, management of the distal ureter remains a controversial issue. We describe a modified method of “pluck” technique using fibrin glue (Tissucol™) in order to improve the oncologic efficacy of this technique. Material & Methods: Since 2007 to September 2008, 10 consecutive patients underwent nephrouretherectomy (6 open and 4 laparoscopic) with our modified distal ureter technique for pelvis and/or caliceal UTCC. Patients were placed in lithotomy position. Cystoscopy was performed with a 23 Fr cystoscope and a 8 Fr ureteral catheter was inserted in the ureter up to 10 cm. At this point, an injection of Tissucol™ 2 ml was performed in order to create a fibrin obstructive cup. After 30 sec, by a 24 Fr resectoscope the ureteric stump was further dissected until the perivescical fat was reached. Results: In both procedures, laparoscopic and open nephrouretherectomy, the ureter was easily identified at the level of iliac artery. The ureter clearly resulted to be overfilled by the obstructive cup. At the end of the procedures all the ureteric specimens were spatulated and transversally dissected in order to evaluate the efficacy of the Tissucol™ cup. In all cases Tissucol™ provided an airtight lumen obstruction. Conclusions: Our modified technique appeared to be a simple, less invasive and oncologically safe method to manage the distal ureter