2,231 research outputs found

    The impact of water on firefighter protective clothing thermal performance and steam burn occurrence in firefighters

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    Exposure to oscillating heat fluxes while having variable water contents in the thermal protective clothing (T.P. C) is possible in a real firefighting scenario. The occurrence of steam burns becomes inevitable in certain conditions which are still unidentified in the literature. In light of such, in this study, the effect of water distribution on thermal protective clothing (T.P.C) performance is studied for various environmental conditions (i.e., fixed and transient values of heat flux). A numerical approach is used to simulate heat and mass transport in the T.P.C.. Parametric studies are performed, where the exposure heat flux (0-80 kW/m(2)) and initial quantities of water in the T.P.C. are varied and correlated with second-degree burn times. The presence of water in the outer shell increases second-degree burn times, while water in the inner layer has the opposite effect for high heat fluxes. For the tested heat fluxes, burns obtained are majorly of a scald nature. The results generated allow for identifying environmental and protective clothing conditions where steam burns may become a potential hazard. This study can directly impact the proceedings for firefighters to take in certain environmental conditions and aid in the design of more effective firefighting protective suits

    Evaluation of the effectiveness of three therapeutic protocols used in the treatment of visceral canine leishmaniosis

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    Leishmaniasis is a tropical and subtropical disease caused by an intracellular protozoan transmitted by a bite from a vector, mainly from the genera Phlebotomus and Lutzomyia, and affects humans and other mammals, especially dogs. The main objective in controlling canine visceral leishmaniasis is to reduce the number of human cases by reducing its prevalence in dogs. In Brazil, glucantime antimoniate and Amphotericin B, utilized for treating the disease in humans, are prohibited so that only miltefosine, which is not employed for treatment of humans, is permitted for use in dogs. This work aimed to evaluate the efficacy of three different therapeutic protocols employed in the treatment of dogs naturally infected with visceral leishmaniasis. Fifty-six (56) dogs, of both sexes, were treated and evaluated utilizing three treatment protocols. The following protocols were utilized: association of several drugs; miltefosine associated with allopurinol; and immunotherapy with anti- Leishmania vaccine associated with Allopurinol. Immunotherapy was the most efficient protocol, followed by an association of drugs and miltefosine. The use of these protocols diminishes the constant relapses of the disease. Associations of therapeutic protocols produced clinical improvement of patients even with presentation of subsequent negative serology. However, the study did not include aspects related to hemoparasitoses, thus a further study is required

    A genetic network that suppresses genome rearrangements in Saccharomyces cerevisiae and contains defects in cancers.

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    Gross chromosomal rearrangements (GCRs) play an important role in human diseases, including cancer. The identity of all Genome Instability Suppressing (GIS) genes is not currently known. Here multiple Saccharomyces cerevisiae GCR assays and query mutations were crossed into arrays of mutants to identify progeny with increased GCR rates. One hundred eighty two GIS genes were identified that suppressed GCR formation. Another 438 cooperatively acting GIS genes were identified that were not GIS genes, but suppressed the increased genome instability caused by individual query mutations. Analysis of TCGA data using the human genes predicted to act in GIS pathways revealed that a minimum of 93% of ovarian and 66% of colorectal cancer cases had defects affecting one or more predicted GIS gene. These defects included loss-of-function mutations, copy-number changes associated with reduced expression, and silencing. In contrast, acute myeloid leukaemia cases did not appear to have defects affecting the predicted GIS genes

    Process simulation and techno-economic assessment for direct production of advanced bioethanol using a genetically modified Synechocystis sp.

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    ABSTRACT: A techno-economic assessment for the direct production of ethanol using a genetically-modified microalgae has been studied. It was considered two main scenarios for process modelling: i) bioenergy-driven microalgae plant, i.e., focused on the production of fuel-grade ethanol and biogas for CHP and, ii) biorefinery-driven microalgae plant, focused on the recovery of added-value bioproducts (zeaxanthin and phycocyanin) along with ethanol and CHP production. These main scenarios and several variants were modelled and optimized for a small-scale demo plant of 1000 Lethanol/day and extrapolated for larger production capacities. Results showed that despite the innovative approach of direct production of ethanol by microalgae, the bioenergy-driven scenario is non-feasible under the studied conditions. Conversely, ethanol production becomes economically feasible as co-product in the biorefinery-driven scenario although having payback periods>10 years. Furthermore, if only bio-based products are produced the NPV and the payback are even more positive, 104.8 M€ and ca. 5 years, respectively.info:eu-repo/semantics/publishedVersio

    Voxel-based registration of simulated and real patient CBCT data for accurate dental implant pose estimation

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    "Progress in Biomedical Optics and Imaging, vol. 16, nr. 42"The success of dental implant-supported prosthesis is directly linked to the accuracy obtained during implant's pose estimation (position and orientation). Although traditional impression techniques and recent digital acquisition methods are acceptably accurate, a simultaneously fast, accurate and operator-independent methodology is still lacking. Hereto, an image-based framework is proposed to estimate the patient-specific implant's pose using cone-beam computed tomography (CBCT) and prior knowledge of implanted model. The pose estimation is accomplished in a threestep approach: (1) a region-of-interest is extracted from the CBCT data using 2 operator-defined points at the implant's main axis; (2) a simulated CBCT volume of the known implanted model is generated through Feldkamp-Davis-Kress reconstruction and coarsely aligned to the defined axis; and (3) a voxel-based rigid registration is performed to optimally align both patient and simulated CBCT data, extracting the implant's pose from the optimal transformation. Three experiments were performed to evaluate the framework: (1) an in silico study using 48 implants distributed through 12 tridimensional synthetic mandibular models; (2) an in vitro study using an artificial mandible with 2 dental implants acquired with an i-CAT system; and (3) two clinical case studies. The results shown positional errors of 67±34μm and 108μm, and angular misfits of 0.15±0.08 and 1.4, for experiment 1 and 2, respectively. Moreover, in experiment 3, visual assessment of clinical data results shown a coherent alignment of the reference implant. Overall, a novel image-based framework for implants' pose estimation from CBCT data was proposed, showing accurate results in agreement with dental prosthesis modelling requirements.This work has been supported by FCT – Fundação para a Ciência e Tecnologia in the scope of the Ph.D. grant SFRH/BD/68270/2010, SFRH/BD/93443/2013 and the project EXPL/BBB-BMD/2146/2013.info:eu-repo/semantics/publishedVersio

    Acute effects of mixed circuit training on hemodynamic and cardiac autonomic control in chronic hemiparetic stroke patients: a randomized controlled crossover trial

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    Objectives: To investigate whether a single bout of mixed circuit training (MCT) can elicit acute blood pressure (BP) reduction in chronic hemiparetic stroke patients, a phenomenon also known as post-exercise hypotension (PEH). Methods: Seven participants (58 ± 12 years) performed a non-exercise control session (CTL) and a single bout of MCT on separate days and in a randomized counterbalanced order. The MCT included 10 exercises with 3 sets of 15-repetition maximum per exercise, with each set interspersed with 45 s of walking. Systolic (SBP) and diastolic (DBP) blood pressure, mean arterial pressure (MAP), cardiac output (Q), systemic vascular resistance (SVR), baroreflex sensitivity (BRS), and heart rate variability (HRV) were assessed 10 min before and 40 min after CTL and MCT. BP and HRV were also measured during an ambulatory 24-h recovery period. Results: Compared to CTL, SBP (∆-22%), DBP (∆-28%), SVR (∆-43%), BRS (∆-63%), and parasympathetic activity (HF; high-frequency component: ∆-63%) were reduced during 40 min post-MCT (p < 0.05), while Q (∆35%), sympathetic activity (LF; low-frequency component: ∆139%) and sympathovagal balance (LF:HF ratio: ∆145%) were higher (p < 0.001). In the first 10 h of ambulatory assessment, SBP (∆-7%), MAP (∆-6%), and HF (∆-26%) remained lowered, and LF (∆11%) and LF:HF ratio (∆13%) remained elevated post-MCT vs. CTL (p < 0.05). Conclusion: A single bout of MCT elicited prolonged PEH in chronic hemiparetic stroke patients. This occurred concurrently with increased sympathovagal balance and lowered SVR, suggesting vasodilation capacity is a major determinant of PEH in these patients. This clinical trial was registered in the Brazilian Clinical Trials Registry (RBR-5dn5zd), available at https://ensaiosclinicos.gov.br/rg/RBR-5dn5zd. Clinical Trial Registration: https://ensaiosclinicos.gov.br/rg/RBR-5dn5zd, identifier RBR-5dn5z

    The Kormendy relation of cluster galaxies in PPS regions

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    We study a sample of 936 early-type galaxies located in 48 low-z regular galaxy clusters with M200≥1014 M⊙M_{200}\geq 10^{14}~ M_\odot at z<0.1z< 0.1. We examine variations in the Kormendy relation (KR) according to their location in the projected phase space (PPS) of the clusters. We have used a combination of Bayesian statistical methods to identify possible differences between the fitted relations. Our results indicate that the overall KR is better fitted when we take into account the information about PPS regions. We also find that objects with time since infall ≥6.5\geq 6.5 Gyr have a significant statistical difference of the KR coefficients relative to objects that are more recent in the cluster environment. We show that giant central ellipticals are responsible for tilting the KR relation towards smaller slopes. These galaxies present a late growth probably due to cumulative preprocessing during infall, plus cannibalism and accretion of smaller stripped objects near the center of the clusters.Comment: 8 pages, 8 figures, appendix, published in MNRAS. arXiv admin note: text overlap with arXiv:2302.0428

    Maternal Low-Protein Diet Deregulates DNA Repair and DNA Replication Pathways in Female Offspring Mammary Gland Leading to Increased Chemically Induced Rat Carcinogenesis in Adulthood

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    Studies have shown that maternal malnutrition, especially a low-protein diet (LPD), plays a key role in the developmental mechanisms underlying mammary cancer programming in female offspring. However, the molecular pathways associated with this higher susceptibility are still poorly understood. Thus, this study investigated the adverse effects of gestational and lactational low protein intake on gene expression of key pathways involved in mammary tumor initiation after a single dose of N-methyl-N-nitrosourea (MNU) in female offspring rats. Pregnant Sprague–Dawley rats were fed a normal-protein diet (NPD) (17% protein) or LPD (6% protein) from gestational day 1 to postnatal day (PND) 21. After weaning (PND 21), female offspring (n = 5, each diet) were euthanized for histological analysis or received NPD (n = 56 each diet). At PND 28 or 35, female offspring received a single dose of MNU (25 mg/kg body weight) (n = 28 each diet/timepoint). After 24 h, some females (n = 10 each diet/timepoint) were euthanized for histological, immunohistochemical, and molecular analyses at PDN 29 or 36. The remaining animals (n = 18 each diet/timepoint) were euthanized when tumors reached ≥2 cm or at PND 250. Besides the mammary gland development delay observed in LPD 21 and 28 groups, the gene expression profile demonstrated that maternal LPD deregulated 21 genes related to DNA repair and DNA replication pathways in the mammary gland of LPD 35 group after MNU. We further confirmed an increased γ-H2AX (DNA damage biomarker) and in ER-α immunoreactivity in mammary epithelial cells in the LPD group at PND 36. Furthermore, these early postnatal events were followed by significantly higher mammary carcinogenesis susceptibility in offspring at adulthood. Thus, the results indicate that maternal LPD influenced the programming of chemically induced mammary carcinogenesis in female offspring through increase in DNA damage and deregulation of DNA repair and DNA replication pathways. Also, Cidea upregulation gene in the LPD 35 group may suggest that maternal LPD could deregulate genes possibly leading to increased risk of mammary cancer development and/or poor prognosis. These findings increase the body of evidence of early-transcriptional mammary gland changes influenced by maternal LPD, resulting in differential response to breast tumor initiation and susceptibility and may raise discussions about lifelong prevention of breast cancer risk.Fil: Zapaterini, Joyce R.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Fonseca, Antonio R. B.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Bidinotto, Lucas T.. Barretos Cancer Hospital; Brasil. Barretos School of Health Sciences; BrasilFil: Colombelli, Ketlin T.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Rossi, André L. D.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Kass, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Salud y Ambiente del Litoral. Universidad Nacional del Litoral. Instituto de Salud y Ambiente del Litoral; ArgentinaFil: Justulin, Luis A.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Barbisan, Luis F.. Universidade Estadual Paulista Julio de Mesquita Filho; Brasi
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