7,313 research outputs found
Aortomesenteric fat thickness with ultrasound predicts metabolic diseases in obese patients
BACKGROUND:: The relation between visceral fat accumulation and development of cardiovascular and metabolic disorders has been demonstrated. The aim of this study was to determine the relationship between a new ultrasound visceral fat thickness (VFT) measurement and clinical and anthropometric data in a consecutive series of obese patients. METHODS:: Fifty-five consecutive male obese patients underwent ultrasound evaluation and metabolic and anthropometric parameters determination at baseline and after 3 weeks of a very low-calorie diet (VLCD) therapy. The new ultrasound measurement, the thickness of the fat between the aorta and the superior mesenteric artery (AMFT), was determined along with the maximum thickness of preperitoneal fat and the global VFT. RESULTS:: AMFT showed a better correlation than VFT and preperitoneal fat with all anthropometric and metabolic parameters, both at baseline and after VLCD regimen. At baseline, patients in the middle and high AMFT and VFT tertiles had a significantly higher prevalence of metabolic diseases with respect to AMFT and VFT low tertile patients, whereas after VLCD period, AMFT only showed significant difference within tertiles. The odds ratios for the various metabolic diseases were higher in the middle and high AMFT tertiles than those in the middle and high VFT tertiles, remaining significant after adjustment for age, body mass index and VLCD regimen only in the middle and high AMFT tertiles. CONCLUSIONS:: The ultrasonographic AMFT evaluation is strongly correlated to the presence of metabolic syndrome and could be a valuable tool to predict metabolic diseases and associated cardiovascular risks in men. © 2013 Lippincott Williams and Wilkins
Maximum Torque Per Watt (MTPW) field-oriented control of induction motor
AbstractA new field-oriented control strategy for induction motor is proposed in the paper. It is called Maximum Torque Per Watt (MTPW) and allows obtaining the minimum value of the sum of the stator and rotor losses due to joule effect, and of the iron losses, for a given value of the reference torque and of the motor speed. Iron losses have been modeled according to Steinmetz equation, separating hysteresis and eddy currents and taking into account the dependence both on the frequency and on the peak value of the flux density. Numerical and experimental results are presented to confirm the validity of the proposed approach, which allows achieving significant improvements in the efficiency of induction motor drive
A blind method to recover the mask of a deep galaxy survey
We present a blind method to determine the properties of a foreground
contamination, given by a visibility mask, that affects a deep galaxy survey.
Angular cross correlations of density fields in different redshift bins are
expected to vanish (apart from a contribution due to lensing), but are
sensitive to the presence of a foreground that modulates the flux limit across
the sky. After formalizing the expected effect of a foreground mask on the
measured galaxy density, under a linear, luminosity-dependent bias model for
galaxies, we construct two estimators that single out the mask contribution if
a sufficient number of independent redshift bins is available. These estimators
are combined to give a reconstruction of the mask. We use Milky-Way reddening
as a prototype for the mask. Using a set of 20 large mock catalogs covering
-th of the sky and number-matched to emitters to mimic an
Euclid-like sample, we demonstrate that our method can reconstruct the mask and
its angular clustering at scales , beyond which the cosmological
signal becomes dominant. The uncertainty of this reconstruction is quantified
to be -rd of the sample variance of the signal. Such a reconstruction
requires knowledge of the average and square average of the mask, but we show
that it is possible to recover this information either from external models or
internally from the data. It also relies on knowledge of how the impact of the
foreground changes with redshift (due to the extinction curve in our case), but
this can be tightly constrained by cross correlations of different redshift
bins. The strong points of this blind reconstruction technique lies in the
ability to find "unknown unknowns" that affect a survey, and in the facility to
quantify, using sets of mock catalogs, how its uncertainty propagates to
clustering measurements. [Abridged]Comment: 43 pages, 16 figures, JCAP, in pres
EXISTING-BIM: INTEGRATED SURVEY PROCEDURES FOR THE MANAGEMENT OF MODERN ARCHITECTURE
Abstract. This paper is aimed at illustrating the operation workflow to create a BIM model of an existing building, by highlighting its process starting from photogrammetric acquisitions and indicating its critical elements as regards data structure and the following modeling. The subject of this study is a reinforced concrete building of the 1960s on six levels. At present, it is undergoing an extensive refurbishment with the purpose of converting its original function, from the US Navy Hospital into offices. Since it was possible to access archive documents concerning the executive design and to carry out even invasive surveys for acquiring specific data about building details, BIM modeling could refer to a significant amount of qualitative and quantitative data. This circumstance characterized the work steps of a BIM modeling which, although referred to an existing building, may also be applied to new constructions. Building technology has implicitly facilitated the identification of the constructive elements and the creation of a list, although the unusual shape of the structure has caused specific problems differently discussed and documented in the text.</p
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