Laparoscopic totally extraperitoneal inguinal hernia repair in the elderly: A prospective control study

Inguinal hernia (IH) repair can be obtained with both open and laparoscopic techniques, which are usually performed using a transabdominal preperitoneal (TAPP) or a totally extraperitoneal (TEP) approach. The aim of the study was to evaluate whether the results of laparoscopic TEP IH repair in the elderly ( 6565 years old) are different with respect to results obtained in younger patients. One hundred and four consecutive patients (four women and 100 men, median age of 57 years, range=21-85 years) with unilateral (N=21, 20.2%) or bilateral (N=83, 79.8%) IH were prospectively enrolled in the study. Patients were divided into two groups according to their age: group A (N=68, 65.4%) aged <65 years and group B (N=36, 34.6%) aged 6565 years. The mean operative time was not significantly different between groups (48\ub120 vs. 52\ub120 min, p=0.33). One case of increased PaCO2 was observed in each group (p=0.72) and two and one case of pneumoperitoneum (p=0.57) in groups A and B, respectively. Two (1.9%) patients (one in each group; p=0.55) required TEP conversion. Mild postoperative complications developed in four patients of each group (p=0.44). After one-year follow-up, three (2.9%) recurrences occurred (group 1=1, group 2=2, p=0.55), both in patients who had undergone direct IH repair. The overall postoperative relative risk of complications related to age was 1.08 (95% confidence interval=0.91-1.27, p=0.53). In conclusion, our results suggest that in patients with IH scheduled for TEP repair, age does not represent a contraindication to surgery in terms of complication rate and postoperative results

The Barker proposal: Combining robustness and efficiency in gradient-based MCMC

There is a tension between robustness and efficiency when designing Markov chain Monte Carlo (MCMC) sampling algorithms. Here we focus on robustness with respect to tuning parameters, showing that more sophisticated algorithms tend to be more sensitive to the choice of step-size parameter and less robust to heterogeneity of the distribution of interest. We characterise this phenomenon by studying the behaviour of spectral gaps as an increasingly poor step-size is chosen for the algorithm. Motivated by these considerations, we propose a novel and simple gradient-based MCMC algorithm, inspired by the classical Barker accept-reject rule, with improved robustness properties. Extensive theoretical results, dealing with robustness to tuning, geometric ergodicity and scaling with dimension, suggest that the novel scheme combines the robustness of simple schemes with the efficiency of gradient-based ones. We show numerically that this type of robustness is particularly beneficial in the context of adaptive MCMC, giving examples where our proposed scheme significantly outperforms state-of-the-art alternatives

Kinematics of z≥6z\geq 6 galaxies from [CII] line emission

We study the kinematical properties of galaxies in the Epoch of Reionization via the [CII] 158$\mu$m line emission. The line profile provides information on the kinematics as well as structural properties such as the presence of a disk and satellites. To understand how these properties are encoded in the line profile, first we develop analytical models from which we identify disk inclination and gas turbulent motions as the key parameters affecting the line profile. To gain further insights, we use "Althaea", a highly-resolved ($30\, \rm pc$) simulated prototypical Lyman Break Galaxy, in the redshift range $z = 6-7$, when the galaxy is in a very active assembling phase. Based on morphology, we select three main dynamical stages: I) Merger , II) Spiral Disk, and III) Disturbed Disk. We identify spectral signatures of merger events, spiral arms, and extra-planar flows in I), II), and III), respectively. We derive a generalised dynamical mass vs. [CII]-line FWHM relation. If precise information on the galaxy inclination is (not) available, the returned mass estimate is accurate within a factor $2$ ($4$). A Tully-Fisher relation is found for the observed high-$z$ galaxies, i.e. $L_{\rm[CII]}\propto (FWHM)^{1.80\pm 0.35}$ for which we provide a simple, physically-based interpretation. Finally, we perform mock ALMA simulations to check the detectability of [CII]. When seen face-on, Althaea is always detected at $> 5\sigma$; in the edge-on case it remains undetected because the larger intrinsic FWHM pushes the line peak flux below detection limit. This suggests that some of the reported non-detections might be due to inclination effects.Comment: 14 pages, 12 figures, accepted for publication in MNRA

The importance of coastal gorgonians in the blue carbon budget

Terrestrial (trees, shrubs) and marine (seaweeds and seagrasses) organisms act as carbon (C) sinks, but the role of benthic suspension feeders in this regard has been largely neglected so far. Gorgonians are one of the most conspicuous inhabitants of marine animal forests (mainly composed of sessile filter feeders); their seston capture rates influence benthic-pelagic coupling processes and they act as C sinks immobilizing carbon in their long-living structures. Three gorgonian species (Paramuricea clavata, Eunicella singularis and Leptogorgia sarmentosa) were studied coupling data of population size structure, biomass and spatial distribution in a NW Mediterranean area (Cap de Creus, Spain) with feeding, respiration and growth rates. In the study area, we calculated that P. clavata sequestered 0.73 ± 0.71 g C m−2 year−1, E. singularis 0.73 ± 0.89 g C m−2 year−1 and L. sarmentosa 0.03 ± 0.02 g C m−2 year−1. To our knowledge, this is the first attempt to calculate the importance as C sinks of gorgonian species that we consider as a starting point to estimate the importance of marine animal forests in C sequestration, and to ensure appropriate management and protection especially in areas and at depths where they are concentrated

A Dirichlet form approach to MCMC optimal scaling

This paper shows how the theory of Dirichlet forms can be used to deliver proofs of optimal scaling results for Markov chain Monte Carlo algorithms (specifically, Metropolis–Hastings random walk samplers) under regularity conditions which are substantially weaker than those required by the original approach (based on the use of infinitesimal generators). The Dirichlet form methods have the added advantage of providing an explicit construction of the underlying infinite-dimensional context. In particular, this enables us directly to establish weak convergence to the relevant infinite-dimensional distributions

Mumificaçao fetal em suínos associada à toxoplasmose.

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SYNTHESIS OF PEPTIDOMIMETIC LIGANDS TARGETING CELL-SURFACE RECEPTORS INVOLVED IN TUMOR ANGIOGENESIS

In the first part of the Thesis, the synthesis of different classes of peptidomimetics targeting integrin receptors is described. Both simple ligands and drug conjugates were synthesized and tested to assess their biological activity. In cancer therapy, peptides and peptidomimetics targeting integrins are employed as carriers to deliver cytotoxic drugs at the tumor site, taking advantage of integrin over-expression on the surface of tumor cells. Within this frame, synthetic efforts have been focused on the synthesis and on the conjugation to the cytotoxic agent paclitaxel of isoDGR-based integrin ligands to effect drug-targeting to integrin over-expressing tumor cells. The second part of the Thesis deals with the vascular endothelial growth factor receptors and their ligands. In particular, the interaction of VEGF-C with VEGFRs has been considered, focusing the attention on the reason why this growth factor was considered a privileged candidate for the preparation of a small library of VEGFR-selective peptides. These peptides have been synthesized by introducing systematic modifications in the natural portion of the growth factor and evaluated as VEGFR binders and anti-angiogenic agents in vitro