8 research outputs found
Comparison between the thermal properties of cement composites using infrared thermal images
The use of agribusiness residual lignocellulosic fibres can be a good alternative in the
development of lignocellulosic composites. The current work aimed to investigate the thermal
performance of cement-based composites with lignocellulosic materials: Eucalyptus, sugarcane
bagasse, coconut fibre in comparison with commercial gypsum board to be used as internal
partitions of the building using infrared thermal images. Three repetitions for each kind of
lignocellulosic material were made, and three commercial gypsum boards were used. In the
production of the panels, the following parameters were applied: material and cement ratio,
1:2.75; water and cement ratio, 1:2.5; hydration water rate of 0.25; additive, 4% (based on cement
mass). The calculations were performed for a nominal panel density of 1,200 kg m-
³. The thermal
analysis was performed in a chamber composed of MDP (Medium-Density Particleboard) and
with an internal layer of rock wool and the heat source (thermal resistance). For the superficial
temperature measurement, a FLIR E75 camera was used to capture the infrared images. When
the internal temperature of the chamber stabilized at 50 °C, an infrared thermal image was
collected from each side of the composite. Thermal properties were analysed: thermal
conductivity, resistivity, resistance, and transmittance. Based on the results, sugar cane cement
composites were characterized by higher values of thermal conductivity. Related to thermal
resistivity, thermal resistance, and thermal transmittance, only the coconut panel presented
similar behaviour to the commercial gypsum board. Thus, cement composite using coconut can
be a potential alternative that might solve energy and environmental concerns simultaneously
Chronic lead intoxication in a jaguar (Panthera onca) shot with round lead pellets - case report
ABSTRACT Lead is a heavy metal and an important cause of acute or chronic toxicosis in humans, domestic, and wild animals. This report aims to describe a case of chronic lead poisoning in a jaguar (Panthera onca) kept under human care that was rescued from the wild environment. The animal was rescued in poor condition in 2004 and kept under human care at the Belo Horizonte Zoological Garden (Minas Gerais, Brazil) until 2020, when it presented with anorexia, vomiting and ataxia. Over the past years the animal had episodes of anemia and increased serum urea and creatinine. Radiography demonstrated 21 radiopaque projectiles on the right side of the face. At necropsy there were multiple projectiles surrounded by fibrous tissue in the subcutaneous of the right side of the face, fibrinous peritonitis, multiple gastric ulcers, and melena. The lead dosage was performed using the atomic absorption spectrometry technique using renal tissue collected at necropsy, with a result of 908 ppb (µg/kg). The findings of projectiles associated with the dosage of lead above the reference limits allow the diagnosis of chronic intoxication in this case
Expression of growth and differentiation factor 9 (GDF-9) and its effect on the in vitro culture of caprine preantral ovarian follicles
AbstractThis study examined the expression of growth and differentiation factor 9 (GDF-9) in caprine ovarian follicles, and the effect of GDF-9 with or without FSH on the in vitro culture of preantral follicles. To evaluate the expression of GDF-9 in Experiment 1, follicles were recovered from 32 goat ovaries and the total RNA isolated and transcribed for real-time polymerase chain reaction (PCR). Experiments 2 and 3 each used a further 32 goat ovaries to provide preantral follicles of ≥150μm. These follicles were isolated and cultured individually in 100μL drops. In each experiment at least 45 follicles were used per treatment. Every 6 days, follicles were evaluated for viability, antrum formation and growth rate. At the end of the culture period, oocytes were submitted to in vitro maturation (IVM), viability tests and chromatin evaluation. In Experiment 2, follicles were cultured in a basal medium (control) or this medium supplemented with GDF-9 at a concentration of 100ng/mL (GDF-9 100) or 200ng/mL (GDF-9 200). The same media were used in Experiment 3, supplemented with recombinant FSH at a level of 100ng/mL from day 0, 500ng/mL from day 6 to 12 and 1000ng/mL from day 12 to 18 of culture to form the three treatments: control FSH, GDF-9 (100) plus FSH and GDF-9 (200) plus FSH. Relative GDF-9 expression (Experiment 1) was greater in the secondary (18units) than the primordial (1unit) and the primary (1unit) preantral follicles (P<0.05). In the antral follicles, GDF-9 expression was significantly higher in the cumulus–oocyte complexes COC's<3mm (1.6units) than those of >3mm diameter (1unit; P<0.05), and in COC's<3mm and >3mm (319.2 and 200.1units, respectively), compared to their respective granulosa and theca cells (1unit for each category, P<0.05). In Experiment 2, GDF-9 supplementation significantly improved the survival of the follicles (60.8%, 66.0% and 77.4% for the control, GDF-9 100 and GDF-9 200, respectively; P<0.05), follicular growth rate and antrum formation following 18 days of culture. Oocyte survival was approximately 100% in all treatments. More oocytes were submitted to IVM from GDF-9 100 (78.0%; P<0.05), compared to GDF-9 200 (48.1%), but no suitable oocytes could be retrieved from the control (58.8%). The proportion of oocytes showing a resumption of meiosis, was not significantly different between treatments (41.4%, 35.9% and 36.0% for the control, GDF-9 100 and GDF-9 200, respectively). The addition of GDF-9 to the media supplemented with FSH (Experiment 3) did not significantly affect any of the variables studied. The proportion of oocytes submitted to IVM in Experiment 3 was 53.3%, 56.5% and 63.8% for the control FSH, GDF-9 100 plus FSH and GDF-9 200 plus FSH, respectively (no statistical differences). The resumption of meiosis was 75.0%, 60.9% and 60.7% for the control FSH, GDF-9 100 plus FSH and GDF-9 200 plus FSH, respectively (NS). The occurrence of metaphase II was very low in both experiments. It was concluded that the supplementation of a basal medium with GDF-9 had a positive effect on the survival and development of caprine preantral follicles, but had no real effect in the presence of FSH
Contratação de Pessoas com Deficiência nas Empresas na Perspectiva dos Profissionais de Recursos Humanos
Density and diversity of filamentous fungi in the water and sediment of Araçá bay in São Sebastião, São Paulo, Brazil
CMS Physics Technical Design Report: Addendum on High Density QCD with Heavy Ions
This report presents the capabilities of the CMS experiment to explore the rich heavy-ion physics programme offered by the CERN Large Hadron Collider (LHC). The collisions of lead nuclei at energies , will probe quark and gluon matter at unprecedented values of energy density. The prime goal of this research is to study the fundamental theory of the strong interaction \u2014 Quantum Chromodynamics (QCD) \u2014 in extreme conditions of temperature, density and parton momentum fraction (low- x ). This report covers in detail the potential of CMS to carry out a series of representative Pb-Pb measurements. These include "bulk" observables, (charged hadron multiplicity, low p T inclusive hadron identified spectra and elliptic flow) which provide information on the collective properties of the system, as well as perturbative probes such as quarkonia, heavy-quarks, jets and high p T hadrons which yield "tomographic" information of the hottest and densest phases of the reaction