Search results for "ratio [mass spectrum]"

TRATTAMENTO INDURATIO PENIS PLASTICA: BENEFICI E SVANTAGGI DELLA EXTRACORPOREAL SHOCK WAVE THERAPY (ESWT). STUDIO PROSPETTICO RANDOMIZZATO VERSUS PLA…

2011

Stable isotope fractionation in speleothems: Laboratory experiments

2010

Abstract In recent years, stalagmites have become important archives for paleoclimate. Several studies applying carbon and oxygen isotopes of stalagmites show a simultaneous increase of δ 13 C and δ 18 O along individual growth layers, which is interpreted as being indicative of isotope fractionation under disequilibrium conditions. In order to obtain robust paleoclimatic information from calcite precipitated under these non-equilibrium conditions it is important to improve the quantitative understanding of the corresponding isotope fractionation processes. Here we present laboratory experiments simulating calcite precipitation under cave-analogue conditions. The major focus was the investi…

Maximum Torque per Ampere Control strategy for low-saliency ratio IPMSMs

2019

This paper deals with electrical drives employing low-saliency ratio interior permanent magnet synchronous motors. In particular, in order to help the designers choosing the best control algorithm, the performances of the Maximum Torque Per Ampere Control (MTPA) and the Field Orientation Control (FOC) are here both theoretically and experimentally assessed and compared, by using, as performance indicators, the torque-current ratio and the power losses. The tests are carried out on a low-power motor for various speeds and loads by implementing the two control strategies in a dSPACE® rapid prototyping system. The results show that the Maximum Torque Per Ampere algorithm has some appreciable a…

Global distributions of diazotrophs Gamma-A nifH genes abundance - Depth integrated values computed from a collection of source datasets - Contributi…

2013

The MAREDAT atlas covers 11 types of plankton, ranging in size from bacteria to jellyfish. Together, these plankton groups determine the health and productivity of the global ocean and play a vital role in the global carbon cycle. Working within a uniform and consistent spatial and depth grid (map) of the global ocean, the researchers compiled thousands and tens of thousands of data points to identify regions of plankton abundance and scarcity as well as areas of data abundance and scarcity. At many of the grid points, the MAREDAT team accomplished the difficult conversion from abundance (numbers of organisms) to biomass (carbon mass of organisms). The MAREDAT atlas provides an unprecedente…

Daphnia females adjust sex allocation in response to current sex ratio and density

2018

Cyclical parthenogenesis presents an interesting challenge for the study of sex allocation, as individuals’ allocation decisions involve both the choice between sexual and asexual reproduction, and the choice between sons and daughters. Male production is therefore expected to depend on ecological and evolutionary drivers of overall investment in sex, and those influencing male reproductive value during sexual periods. We manipulated experimental populations, and made repeated observations of natural populations over their growing season, to disentangle effects of population density and the timing of sex from effects of adult sex ratio on sex allocation in cyclically parthenogenetic Daphnia…

Comparison of isotope ratio mass spectrometry and nondispersive isotope-selective infrared spectroscopy for 13C-urea breath test.

1999

The 13C-urea breath test (UBT) is a sensitive and noninvasive method to diagnose Helicobacter pylori infection, but mass spectrometry (IRMS) is very expensive. The aims of this study were to compare the new low-priced infrared spectroscopy with IRMS in detecting the infection and to assess the influence of feeding on test accuracy.One hundred thirty-four patients with dyspeptic symptoms were recruited. Of these, 74 were infected and 60 uninfected on the basis of both CLO-test and histology. A subgroup of 37 patients (22 H. pylori-positive and 15 H. pylori-negative) was studied under fasting and nonfasting conditions on two different days. Duplicate breath samples were analyzed with two IRMS…

Cytokine gene expression in the tunica albuginea of patients with Peyronie's disease. Pilot study with a control group.

2012

Introduction and objective Cytokines may be involved in the pathogenesis of Peyronie's disease (PD). In this case, biological drugs, acting on specific cytokines, could be adopted in the pharmacological treatment of the disease. Materials and Methods Twenty PD patients and 8 patients affected by congenital recurvatum penis (control group) who underwent corporoplasty were enrolled in the study Histological examination and measurement by Real Time PCR of the expression of the encoding genes for IL-2, IL-4, IL-6, IL-10, IL-13, TGF-β, TNF-α and IFN-γ were performed on the removed tunica albuginea (TA). For the normalization of data GAPDH (glucerldehyde-3fosfatehydrogenase) and GUSB (β-glucuroni…

Does Transfer Capacitive Resistive Energy Has a Therapeutic Effect on Peyronie's Disease? Randomized, Single-Blind, Sham-Controlled Study on 96 Patie…

2017

<b><i>Background/Aims/Objectives:</i></b> We have investigated the clinical and physiological effects of Transfer Capacitive Resistive Energy (TCARE) therapy on men with Peyronie's disease (PD). <b><i>Methods:</i></b> Ninety-six men with PD have been randomized in a 2:1 ratio to receive 3 sessions of TCARE therapy or sham therapy. Pain, penile curvature and erectile function have been assessed before the first treatment and up to 9 months after the end of treatment, using the Visual Analogue Scale for the pain, a goniometer to measure the degree of curvature using at-home photography and an International Index of Erectile Function (IIEF-5) que…

Weighted Least-Squares Likelihood Ratio Test for Branch Testing in Phylogenies Reconstructed from Distance Measures

2005

A variety of analytical methods is available for branch testing in distance-based phylogenies. However, these methods are rarely used, possibly because the estimation of some of their statistics, especially the covariances, is not always feasible. We show that these difficulties can be overcome if some simplifying assumptions are made, namely distance independence. The weighted least-squares likelihood ratio test (WLS-LRT) we propose is easy to perform, using only the distances and some of their associated variances. If no variances are known, the use of the Felsenstein F-test, also based on weighted least squares, is discussed. Using simulated data and a data set of 43 mammalian mitochondr…

Contrasting shell growth strategies in two Mediterranean bivalves revealed by oxygen-isotope ratio geochemistry: The case of Pecten jacobaeus and Gly…

2019

International audience; High-resolution stable-isotope ratio data (delta O-18, delta O-18) were used to study growth strategies of two bivalve species, Pecten jacobaeus (calcitic shell) and Glycymeris pilosa (aragonitic shell) from the North Adriatic Sea. The principal objectives of this study were to identify the period of the year when the growth line is formed in the shell of two target species, to identify the main growing season of these two species, to identify the environmental drivers of shell growth, and to evaluate the potential applicability of delta O-18 and delta O-18 values for the reconstruction of environmental variability. Samples were collected from the North Adriatic Sea …