1,985 research outputs found

    Aortomesenteric fat thickness with ultrasound predicts metabolic diseases in obese patients

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    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

    Comparative seismic performance of a moment frame equipped with Lateral Impact Resilient Double Concave Frictional devices

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    This study presents a comparative assessment of the seismic performance of a reinforced concrete moment frame equipped with a new isolator. The Lateral Impact Resilient Double Concave Friction Pendulum (LIR-DCFP) bearing has an enhanced inner slider capable of limiting the magnitude of the lateral impact force generated between the inner slider and the restraining rims of the sliding surfaces. Due to the presence of a plane high-friction interface with an internal gap, the novel isolator has an increased energy dissipation capacity that is activated during the lateral impact. Three isolation systems were considered to evaluate the benefits of using LIR-DCFP devices. One conformed by the suggested isolator, and two composed of classic non-articulated Double Concave Friction Pendulum (DCFP) bearings. The isolation devices were modelled employing a numerical formulation based on rigid body dynamics, capable of accounting for the lateral impact behaviour. The superstructure, a reinforced concrete moment resisting frame designed according to the American ASCE/SEI 7-16 standard, was modelled using beam-column elements considering geometric and material nonlinearities. Furthermore, the degrading behaviour of the building was incorporated using a proper degradation model for both the stiffness and the force. Incremental Dynamic Analyses (IDAs) were performed considering the friction coefficient as a random variable to characterize the statistics of the maximum inter-story responses. With the data generated in the IDAs, fragility curves related to the superstructure performance were constructed. Finally, employing the hazard curve, reliability curves were derived. The superstructure equipped with LIR-DCFP bearings presents better seismic performance than the same building equipped with the same size DCFP isolators. The benefits of using the new isolator are not achieved by increasing the lateral capacity of the classic isolation system

    Model uncertainty in non-linear numerical analyses of slender reinforced concrete members

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    The present study aims to characterize the epistemic uncertainty within the use of global non-linear numerical analyses (i.e., NLNAs) for design and assessment purposes of slender reinforced concrete (RC) members. The epistemic uncertainty associated to NLNAs may be represented by approximations and choices performed during the definition of a structural numerical model. In order to quantify epistemic uncertainty associated to a non-linear numerical simulation, the resistance model uncertainty random variable has to be characterized by means of the comparison between experimental and numerical results. With this aim, a set of experimental tests on slender RC columns known from the literature is considered. Then, the experimental results in terms of maximum axial load are compared to the outcomes achieved from NLNAs. Nine different modeling hypotheses are herein considered to characterize the resistance model uncertainty random variable. The probabilistic analysis of the results has been performed according to Bayesian approach accounting also for both the previous knowledge from the scientific literature and the influence of the experimental uncertainty on the estimation of the statistics of the resistance model uncertainty random variable. Finally, the resistance model uncertainty partial safety factor is evaluated in line with the global resistance format of fib Model Code for Concrete Structures 2010 with reference to new and existing RC structures

    In vitro bioaccessibility and antioxidant activity of coffee silverskin polyphenolic extract and characterization of bioactive compounds using UHPLC-Q-Orbitrap HRMS

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    Coffee silverskin (CS), the main by-product in the coffee industry, contains a vast number of human health-related compounds, which may justify its exploitation as a functional food ingredient. This study aimed to provide a comprehensive analysis of the polyphenolic and alkaloid profile through UHPLC-Q-Orbitrap HRMS analysis. The bioaccessibility of total phenolic compounds and changes in the antioxidant activity during an in vitro gastrointestinal digestion were also evaluated through spectrophotometric tests (TPC by Folin-Ciocalteu, ABTS, DPPH, and FRAP), to elucidate their effcacy for future applications in the nutraceutical industry. Caffeoylquinic and feruloylquinic acids were the most representative polyphenols, with a mean concentration of 5.93 and 4.25 mg/g, respectively. Results showed a high content of caffeine in the analyzed CS extracts, with a mean value of 31.2 mg/g, meaning a two-fold increase when compared to coffee brews. Our findings highlighted that both the bioaccessibility and antioxidant activity of CS polyphenols significantly increased in each in vitro gastrointestinal digestion stage. In addition, the colon stage might constitute the main biological site of action of these antioxidant compounds. These results suggest that in vivo, the dietary polyphenols from CS might be metabolized by human colonic microflora, generating metabolites with a greater antioxidant activity, increasing their well-known beneficial effects

    Gingival crevicular fluid protein content and alkaline phosphatase activity in relation to pubertal growth phase

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    OBJECTIVE: To evaluate gingival crevicular fluid (GCF) protein content and alkaline phosphatase (ALP) activity in growing subjects in relation to stages of skeletal maturation, ie, the growth phase, as prepubertal, pubertal, and postpubertal. SUBJECTS AND METHODS: Fifty healthy growing subjects (31 girls and 19 boys; age range, 7.8–17.7 years) were enrolled in this study that followed a double-blind, prospective, cross-sectional design. Collection of GCF was performed at the mesial and distal sites of both central incisors, for the maxilla and mandible. Growth phase was assessed through the cervical vertebral maturation method. GCF parameters were expressed as total protein content, total ALP activity, and normalized ALP activity. RESULTS: The total GCF protein content was similar between the different growth phases. On the contrary, the total ALP activity showed a peak for the pubertal growth phase. The normalized GCF ALP activity was only poorly associated with growth phase. No differences were seen between the maxillary and mandibular sites, or between the sexes, for any GCF parameter. CONCLUSIONS: The total GCF protein content is not sensitive to the growth phase. However, GCF ALP activity has potential as a diagnostic aid for identification of the pubertal growth phase in individual subjects when expressed as total, but not normalized, values

    Ultra-high-performance liquid chromatography coupled with quadrupole Orbitrap high-resolution mass spectrometry for multi-residue analysis of mycotoxins and pesticides in botanical nutraceuticals

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    Cannabidiol (CBD) food supplements made of Cannabis sativa L. extracts have quickly become popular products due to their health-promoting effects. However, potential contaminants, such as mycotoxins and pesticides, can be coextracted during the manufacturing process and placed into the final product. Accordingly, a novel methodology using ultra-high-performance liquid chromatography coupled with quadrupole Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) was developed to quantify 16 mycotoxins produced by major C. sativa fungi, followed by a post-target screening of 283 pesticides based on a comprehensive spectral library. The validated procedure was applied to ten CBD-based products. Up to six different Fusarium mycotoxins were found in seven samples, the most prevalent being zearalenone (60%) and enniatin B1 (30%), both found at a maximum level of 11.6 ng/g. Co-occurrence was observed in four samples, including one with enniatin B1, enniatin A and enniatin A1. On the other hand, 46 different pesticides were detected after retrospective analysis. Ethoxyquin (50%), piperonyl butoxide (40%), simazine (30%) and cyanazine (30%) were the major residues found. These results highlight the necessity of monitoring contaminants in food supplements in order to ensure a safe consumption, even more considering the increase trend in their use. Furthermore, the developed procedure is proposed as a powerful analytical tool to evaluate the potential mycotoxin profile of these particular products

    Target quantification and semi-target screening of undesirable substances in pear juices using ultra-high-performance liquid chromatography-quadrupole orbitrap mass spectrometry

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    Fruit juices are common products in modern diets due to the supply of vegetal nutrients combined with its tastiness. Nevertheless, potential contaminants, such as mycotoxins and pesticides, can be present in commercial products due to a potential carry-over. Therefore, the aim of this study was to investigate for the first time the presence of 14 Fusarium mycotoxins using a quick, easy, cheap, effective, rugged, and safe (QuEChERS)-based extraction followed by an ultra-high-performance liquid chromatography-quadrupole Orbitrap high-resolution mass spectrometry in 21 pear juice samples from Italian markets. Up to nine different mycotoxins were detected, particularly an extensive presence of zearalenone (67%, n = 21, mean value = 0.88 ng/mL). Emerging Fusarium mycotoxins enniatins B, B1, A, and A1 were also detected. Additionally, 77 pesticide residues were tentatively identified through a retrospective analysis based on a mass spectral library. The prevalent presence of some non-approved pesticides, such as ethoxyquin (64%, n = 21) and triazophos (55%, n = 21), must be highlighted. The results obtained indicate an extensive contamination of marketed pear juice with undesirable compounds, and they should be taken into consideration when performing risk assessment studies

    Systemic approach to the management of infrastructure safety: Organizational items

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    This study deals with the organizational items within a systemic approach finalized to make the safety management of road infrastructures more sustainable at a scale of territory. In fact, the infrastructure safety is a very relevant topic in many states with structural systems built some decades ago. Beyond the inherent structural problems, other items are worthy to be investigated, such as, social, economic and organizational aspects. With this aim, the study describes a systemic approach finalized to make all the public and private stakeholders active actors in the management process by improving the organizational items: interaction and mode of governance. In detail, regarding a case study in an Italian region, the authors propose to take on the satellite-based information to investigate the structural safety problems of the infrastructures at a scale of territory. Along this issue, risk or alert maps are properly defined. Successively, useful suggestions are discussed with the focus to increase the interactions between the different actors for a better management of the safety. The recommendations are able to improve the governance mode and decision process with a more all-inclusive level of organization

    First-Year Teachers’ Perceptions of the Mentor Program in a Southeastern School District

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    Many educators are leaving their teaching positions, especially in the early years of their career. This has led many states and districts to mandate teacher mentor programs for new teachers with the hope of retaining these teachers. However, even with these mentor programs, new teachers are continuing to leave their positions, which affects the district, the school, its employees, and the students. A lack of knowledge about teachers’ experiences as mentees in mentoring programs limits a state’s ability to improve programs. This study was conducted to address this gap in knowledge. The purpose of this qualitative study was to explore new teachers’ perceptions of their experiences with their state’s mentor program and how they feel supported by the mentor program. The theoretical framework for this study was the Knowles’s adult learning theory, andragogy. A generic qualitative approach was used to learn about new teachers’ experiences. Participants were nine teachers within a suburban school district in a Southeastern state. Semi structured interview questions were used to gather data regarding teachers’ description of their experiences. Data were interpreted through a thematic analysis. Four themes were identified in response to the research questions: (a) mentees’ relationships with mentor determine outcome, (b) mentees’ sense of community, (c) mentor communication with mentee, and (d) mentor program’s overall structure. This study’s findings may have potential implications for positive social change within school districts and the ways they support new teachers. Greater support for new teachers may increase teacher retention and contribute to positive social change in the community

    FULL SCALE TESTS OF THE BASE-ISOLATION SYSTEM FOR AN EMERGENCY HOSPITAL

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    The paper presents the results of some full-scale tests regarding the base-isolation system of the emergency room building of the polyclinic hospital in Palermo (Italy). This building has been recently realized and its base isolation system is characterized by double friction pendulum isolators. Static lateral pushing tests were aimed at identifying fundamental mechanical properties of the whole isolation level (e.g. friction forces and stiffness) in order to verify the agreement with the design hypotheses. Further dynamic tests provided different displacements of the isolated base followed by the instantaneous release (snap-back tests), in order to verify the effectiveness, the mechanical parameter in dynamics and re-centering capacity of the isolation system. The design of both the types of test and the respective results and interpretations are illustrated in the paper highlighting a number of issues arising when arranging such kind of investigations on full scale buildings
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