Outcome After Therapeutic Lymph Node Dissection in Patients with Unknown Primary Melanoma Site

Purpose: The aim of this study was to evaluate the incidence and outcome of melanoma of unknown primary site (MUP) after therapeutic lymph node dissection (TLND) of palpable nodal melanoma metastases. Disease-free (DFS) and overall survival (OS) time of MUP patients were analyzed and compared to patients undergoing a TLND for known primary melanomas (MKP). Methods: This single institution retrospective study analyzed 342 consecutive patients who were treated with 415 TLNDs for palpable nodal disease from 1982 to 2009. Univariate and multivariate analyses included: MUP versus MKP, gender, Breslow thickness, ulceration of primary tumor, site of prima

Fermentative production of isobutene

Isobutene (2-methylpropene) is one of those chemicals for which bio-based production might replace the petrochemical production in the future. Currently, more than 10 million metric tons of isobutene are produced on a yearly basis. Even though bio-based production might also be achieved through chemocatalytic or thermochemical methods, this review focuses on fermentative routes from sugars. Although biological isobutene formation is known since the 1970s, extensive metabolic engineering is required to achieve economically viable yields and productivities. Two recent metabolic engineering developments may enable anaerobic production close to the theoretical stoichiometry of 1isobutene + 2CO2 + 2H2O per mol of glucose. One relies on the conversion of 3-hydroxyisovalerate to isobutene as a side activity of mevalonate diphosphate decarboxylase and the other on isobutanol dehydration as a side activity of engineered oleate hydratase. The latter resembles the fermentative production of isobutanol followed by isobutanol recovery and chemocatalytic dehydration. The advantage of a completely biological route is that not isobutanol, but instead gaseous isobutene is recovered from the fermenter together with CO2. The low aqueous solubility of isobutene might also minimize product toxicity to the microorganisms. Although developments are at their infancy, the potential of a large scale fermentative isobutene production process is assessed. The production costs estimate is 0.9 € kg−1, which is reasonably competitive. About 70% of the production costs will be due to the costs of lignocellulose hydrolysate, which seems to be a preferred feedstock

First Observation of Heavy Baryons \Sigma_b and \Sigma_b^*

We report an observation of new bottom baryons produced in proton-antiproton collisions at the Tevatron. Using 1.1 fb^{-1} of data collected by the CDF II detector, we observe four \Lambda_b^0\pi^{\pm} resonances in the fully reconstructed decay mode \Lambda_b^0 \to \Lambda_c^+ \pi^-, where \Lambda_c^+ \to p K^- \pi^+. We interpret these states as the \Sigma_b^{(*)\pm} baryons and measure the following masses: m_{\Sigma_b^+} = 5807.8^{+2.0}_{-2.2}(stat.) \pm 1.7(syst.) MeV/c^2, m_{\Sigma_b^-} = 5815.2 \pm 1.0(stat.) \pm 1.7(syst.) MeV/c^2, and m(\Sigma_b^*) - m(\Sigma_b) = 21.2^{+2.0}_{-1.9}(stat.) ^{+0.4}_{-0.3}(syst.) MeV/c^2.Comment: 7 Pages, 2 Figures, 2 Tables. Submitted to Phys. Rev. Let

The LOFT mission concept: a status update

The Large Observatory For x-ray Timing (LOFT) is a mission concept which was proposed to ESA as M3 and M4 candidate in the framework of the Cosmic Vision 2015-2025 program. Thanks to the unprecedented combination of effective area and spectral resolution of its main instrument and the uniquely large field of view of its wide field monitor, LOFT will be able to study the behaviour of matter in extreme conditions such as the strong gravitational field in the innermost regions close to black holes and neutron stars and the supra-nuclear densities in the interiors of neutron stars. The science payload is based on a Large Area Detector (LAD, >8m2 effective area, 2-30 keV, 240 eV spectral resolution, 1 degree collimated field of view) and a Wide Field Monitor (WFM, 2-50 keV, 4 steradian field of view, 1 arcmin source location accuracy, 300 eV spectral resolution). The WFM is equipped with an on-board system for bright events (e.g., GRB) localization. The trigger time and position of these events are broadcast to the ground within 30 s from discovery. In this paper we present the current technical and programmatic status of the mission

Faint objects in motion: the new frontier of high precision astrometry

Funder: Istituto Nazionale di AstrofisicaSky survey telescopes and powerful targeted telescopes play complementary roles in astronomy. In order to investigate the nature and characteristics of the motions of very faint objects, a flexibly-pointed instrument capable of high astrometric accuracy is an ideal complement to current astrometric surveys and a unique tool for precision astrophysics. Such a space-based mission will push the frontier of precision astrometry from evidence of Earth-mass habitable worlds around the nearest stars, to distant Milky Way objects, and out to the Local Group of galaxies. As we enter the era of the James Webb Space Telescope and the new ground-based, adaptive-optics-enabled giant telescopes, by obtaining these high precision measurements on key objects that Gaia could not reach, a mission that focuses on high precision astrometry science can consolidate our theoretical understanding of the local Universe, enable extrapolation of physical processes to remote redshifts, and derive a much more consistent picture of cosmological evolution and the likely fate of our cosmos. Already several missions have been proposed to address the science case of faint objects in motion using high precision astrometry missions: NEAT proposed for the ESA M3 opportunity, micro-NEAT for the S1 opportunity, and Theia for the M4 and M5 opportunities. Additional new mission configurations adapted with technological innovations could be envisioned to pursue accurate measurements of these extremely small motions. The goal of this White Paper is to address the fundamental science questions that are at stake when we focus on the motions of faint sky objects and to briefly review instrumentation and mission profiles