This work deals with the synthesis of Na-P1 (GIS) zeolite using rice husk as the starting material, instead of the more expensive chemicals currently used in the industry (i.e., Na aluminates and Na silicates).
View Article and Find Full Text PDFThe present work deals with the hydrothermal synthesis of a Na-A (LTA) zeolite using rice husk as a starting material. The focus was on defining the most favorable conditions for the synthesis of zeolite Na-A from rice husk in order to economize on both energy (i.e.
View Article and Find Full Text PDFThis study assesses the potential impacts on human health of volcanic ash emitted during the 2021 Tajogaite eruption (La Palma Island, Spain). Ash samples were physically and chemically characterized and leaching tests (with deionized water and acidic solution) were performed according to the IVHHN protocols to elucidate i) the leachable elements that may affect water quality and represent a potential threat for livestock and humans through drinking water supply; and ii) the bioaccessible fraction of toxicants able to be solubilized from ash surfaces if ashes are incidentally ingested by children. The most abundant readily water-soluble compounds were SO, F, Cl, Na, Ca, Ba, Mg, and Zn.
View Article and Find Full Text PDFAmmonium -(pyridin-2-ylmethyl)oxamate (AmPicOxam), synthesized from -methyl--(pyridin-2-ylmethyl)oxamate, was spectroscopically and structurally characterized and assayed as a novel precursor for the protection and consolidation of carbonate stone substrates. An in-depth characterization of treated and untreated biomicritic limestone and white Carrara marble samples was carried out by means of SEM microscopy, X-ray powder diffraction, helium pycnometry, determination of water transport properties, and pull-off tests. The improved solubility (1.
View Article and Find Full Text PDFIonic exchange tests have been performed on superficial wastewaters to remove ammonia using a volcanic zeolitized rock from Lazio Region (Central Italy). The zeolitite (natural zeolite) is characterized by chabazite, phillipsite and minor amounts of sanidine, leucite and analcime. After preliminary column experiments in laboratory focused to determine the saturation time of the zeolitite, a pilot plant was built up on a little water course near the area of San Giustino channel (Abruzzo Region, Central Italy).
View Article and Find Full Text PDFAnalcime is nowadays an important component in dental porcelain systems, in heterogeneous catalysis, in the nanoelectronic field, in selective adsorption and in stomatology (dental filling and prosthesis). Analcime synthesis from an impure, silica-rich kaolinite rock coming from Romana (Sassari, Italy) is here presented. A synthesis protocol is proposed that aims to make an improvement of synthesis conditions compared to the past.
View Article and Find Full Text PDFThe use of agroindustry by-products in animal diets allows the use of residues that are not fit for human consumption. In this study, it was investigated whether fattening commercial rabbits during 30 days with a non-medicated feed, with 20% addition of grape pomace (GPD), affected production traits and the fatty acid composition, antioxidants properties, and the shelf life of the meat compared to a conventional strategy (CON). Furthermore, it was tested, by chromatographic analysis, whether this alternative diet allowed the transfer of phenolic compounds to the meat.
View Article and Find Full Text PDFReproductive traits in breeding herds can be improved through crossbreeding, which results in breed differences, heterosis and breed complementarity. The aim of this study was to estimate group additive genetic and dominance effects for three reproductive traits; probability of artificial insemination (AIP); calving success (CS); and days to calving (DC) for Hereford (H), Angus (A), Nellore (N) and Salers (S) breeds under grazing conditions. Data were obtained from an experiment carried out during 1992-2002 by the Faculty of Agronomy, Universidad de la Republica (UdelaR), Uruguay and Caja Notarial de Seguridad Social.
View Article and Find Full Text PDFThis work focuses on the hydrothermal synthesis of Na-P zeolite by using a kaolinite rock coming from Romana (Sassari, Italy). The kaolin is calcined at a temperature of 650 °C and then mixed with calculated quantities of NaOH. The synthesis runs are carried out at ambient pressure and at variable temperatures of 65 and 100 °C.
View Article and Find Full Text PDFThis work is a part of a research project conducted in order to characterize the volcanic ash from Mount Etna, focusing in particular on the surface reactivity of ashes and possible consequence for human health. In this framework, a sampling campaign began on 16 March 2013, taking advantage of the intense volcanic activity on Etna. The interaction between volcanic ash and human organism was simulated treating two classes of representative Etnean particles with ultrapure water (grainsize of 850 um) and Gamble's solution mimic lug fluids (grainsize <38 μm) with the aim to evaluate the risk due to gastric and respiratory exposure to volcanic particles.
View Article and Find Full Text PDFCrystallization of zeolite Li-A(BW) from kaolinite (Standard Porcelain by the IMERYS Minerals Ltd) through a conventional hydrothermal treatment is here achieved for the first time with no additives as reported in the literature. Moreover lower kaolin calcination temperatures and lower synthesis temperatures are tested and verified in this work. The synthesis process is rather simple as the reaction of kaolinite with alkali occurs very readily after calcination of at 650 °C.
View Article and Find Full Text PDFLeucite is nowadays an important component in ceramic restoration systems with particular suitability to dental porcelains. The leucite synthesis from a hydrothermally-derived precursor is here presented. A silicate solution was prepared by mixing a naturally derived amorphous silica (diatomitic rock from Crotone, southern Italy) with potassium hydroxide and an aluminate solution was obtained by mixing aluminium hydroxide and potassium hydroxide.
View Article and Find Full Text PDFImproving meat production traits has increased its importance in sheep breeding. We report novel associations of SNP present in genes related to lipid metabolism and growth with several carcass traits in purebred Texel lambs. Expected progeny differences (EPD) predictions from 461 animals from the Central Progeny Testing of Texel breed in Uruguay were used for the association analysis.
View Article and Find Full Text PDFStudy Design: A cross-sectional survey with a longitudinal follow-up.
Objectives: The aim of this study was to test the hypothesis that pain, which is localized to the low back, differs epidemiologically from that which occurs simultaneously or close in time to pain at other anatomical sites SUMMARY OF BACKGROUND DATA.: Low back pain (LBP) often occurs in combination with other regional pain, with which it shares similar psychological and psychosocial risk factors.
This article aimed to present a basic questionnaire and minimum methodological criteria for consideration in future Surveys on Working Conditions, Employment, and Health in Latin America and the Caribbean. A virtual and face-to-face consensus process was conducted with participation by a group of international experts who used the surveys available up until 2013 as the point of departure for defining the proposal. The final questionnaire included 77 questions grouped in six dimensions: socio-demographic characteristics of workers and companies; employment conditions; working conditions; health status; resources and preventive activities; and family characteristics.
View Article and Find Full Text PDFBackground: As the world's population ages, the prevalence of multiple chronic and non-chronic health-related conditions is increasing. Research on multimorbidity, the co-occurrence of two or more health-related conditions, has mainly involved patient and older populations. Its effect in working populations, presumably younger and healthier, is not well known but could conceivably affect sickness absence (SA) and ability to return to work.
View Article and Find Full Text PDFObjectives Patients with common mental disorders (CMDs) often suffer from comorbidities, which may limit their functioning at work. We assessed the longitudinal impact of multimorbidity, defined as two or more co-occurring chronic health conditions, on work functioning over time among workers who had returned to work after sick leave due to CMDs. Methods Prospective cohort study of 156 workers followed for 1 year after return to work from sick leave due to CMDs.
View Article and Find Full Text PDFSomatising tendency, defined as a predisposition to worry about common somatic symptoms, is importantly associated with various aspects of health and health-related behaviour, including musculoskeletal pain and associated disability. To explore its epidemiological characteristics, and how it can be specified most efficiently, we analysed data from an international longitudinal study. A baseline questionnaire, which included questions from the Brief Symptom Inventory about seven common symptoms, was completed by 12,072 participants aged 20-59 from 46 occupational groups in 18 countries (response rate 70%).
View Article and Find Full Text PDFThe goal of this multiphased research is to develop methods to comprehensively determine the economic impact of hearing impairment and noise-induced hearing injury among active duty U.S. Service Members.
View Article and Find Full Text PDFObjectives: The aim of this study was to examine the presence of a dose-response relationship between work hours and incident cardiovascular disease (CVD) in a representative sample of U.S. workers.
View Article and Find Full Text PDFTo inform case definition for neck/shoulder pain in epidemiological research, we compared levels of disability, patterns of association, and prognosis for pain that was limited to the neck or shoulders (LNSP) and more generalised musculoskeletal pain that involved the neck or shoulder(s) (GPNS). Baseline data on musculoskeletal pain, disability, and potential correlates were collected by questionnaire from 12,195 workers in 47 occupational groups (mostly office workers, nurses, and manual workers) in 18 countries (response rate = 70%). Continuing pain after a mean interval of 14 months was ascertained through a follow-up questionnaire in 9150 workers from 45 occupational groups.
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