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1.
Bull Math Biol ; 85(5): 39, 2023 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-37000280

RESUMO

Continuous-time Markov chains are frequently used as stochastic models for chemical reaction networks, especially in the growing field of systems biology. A fundamental problem for these Stochastic Chemical Reaction Networks (SCRNs) is to understand the dependence of the stochastic behavior of these systems on the chemical reaction rate parameters. Towards solving this problem, in this paper we develop theoretical tools called comparison theorems that provide stochastic ordering results for SCRNs. These theorems give sufficient conditions for monotonic dependence on parameters in these network models, which allow us to obtain, under suitable conditions, information about transient and steady-state behavior. These theorems exploit structural properties of SCRNs, beyond those of general continuous-time Markov chains. Furthermore, we derive two theorems to compare stationary distributions and mean first passage times for SCRNs with different parameter values, or with the same parameters and different initial conditions. These tools are developed for SCRNs taking values in a generic (finite or countably infinite) state space and can also be applied for non-mass-action kinetics models. When propensity functions are bounded, our method of proof gives an explicit method for coupling two comparable SCRNs, which can be used to simultaneously simulate their sample paths in a comparable manner. We illustrate our results with applications to models of enzymatic kinetics and epigenetic regulation by chromatin modifications.


Assuntos
Algoritmos , Conceitos Matemáticos , Processos Estocásticos , Epigênese Genética , Modelos Biológicos , Cadeias de Markov , Cinética
2.
J Trop Pediatr ; 69(2)2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36897068

RESUMO

The present study aimed to analyze the prevalence of childhood obesity in Brazil and compare it between boys and girls. This systematic review was conducted and reported according to the guidelines outlined in the PRISMA statement. A systematic search of electronic databases, including PubMed, LILACS, and SciELO, was performed in November 2021. Studies that met the following criteria were included: (i) original quantitative studies regardless of their design; (ii) childhood obesity was clearly defined; (iii) prevalence of childhood obesity was reported or it was possible to extract from tables or figures in the text; and (iv) eligible population included children under 12 years of age. A total of 112 articles were included in the systematic review. The prevalence of childhood obesity in Brazil was of 12.2%, being 10.8% in girls and 12.3% in boys. In addition, wide heterogeneity in the childhood obesity prevalence was observed between the states, since it was 2.6% in Pará, while it was 15.8% in Rondônia. Thus, the importance of urgently implementing measures to prevent and treat childhood obesity should be emphasized aiming to reduce obese children and adolescents and future health problems in adult life resulting from this cardiovascular risk factor.


Assuntos
Obesidade Infantil , Masculino , Adulto , Adolescente , Feminino , Criança , Humanos , Obesidade Infantil/epidemiologia , Prevalência , Brasil
3.
Trop Anim Health Prod ; 55(6): 384, 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37897539

RESUMO

Limited information exists on the use of zinc-l-selenomethionine (Zn-L-SeMet) in broiler diets and its effects on the growth performance, body temperature, mortality rates, blood profile, and gene expression, especially when animals are reared under cyclic heat stress conditions. This study aimed to investigate the impact of Zn-L-SeMet in broiler diets from 1 to 42 days of age reared under cyclic heat stress and its effects on growth performance, cloacal temperatures, mortality rate, blood parameters, and insulin-like growth factor 1 (IGF-1) and growth hormone receptor (GHR) gene expression in the breast muscle. A total of 1000 male Cobb 500® broiler chicks were randomly assigned to five treatments: 0, 0.15, 0.23, 0.47, and 1.30 mg/kg of Zn-L-SeMet. Each treatment consisted of 10 replicates with 20 birds each. No statistically significant differences in growth performance were observed from 1 to 21 days of age (P > 0.05). However, from 1 to 42 days, feed intake (FI) and feed conversion ratio (FCR) decreased linearly (P < 0.05). Cloacal temperatures showed no significant effects (P > 0.05), while overall mortality rate exhibited a quadratic response (P < 0.05), with the optimal inclusion level predicted to reduce broiler mortality at 0.71 mg/kg. Triglyceride (TRG) levels increased with 0.97 mg/kg (P < 0.05), and gama-glutamil transferase (GGT) levels decreased with the inclusion of 1.19 mg/kg (P < 0.05). No significant effects on IGF-1 and GHR gene expression were found (P > 0.05). In conclusion, the inclusion of 1.30 mg/kg of Zn-L-SeMet in diets of heat-stressed broilers improved growth performance from 1 to 42 days of age. An inclusion of 0.71 mg/kg reduced mortality rate, while 0.97 mg and 1.19 mg increased and reduced TRG and GGT levels, respectively.


Assuntos
Selenometionina , Zinco , Animais , Masculino , Selenometionina/metabolismo , Galinhas , Suplementos Nutricionais , Fator de Crescimento Insulin-Like I/metabolismo , Dieta/veterinária , Resposta ao Choque Térmico , Ração Animal/análise
4.
Int J Mol Sci ; 23(21)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36362362

RESUMO

A momentary increase in cytoplasmic Ca2+ generates an oscillation responsible for the activation of proteins, such as calmodulin and kinases, which interact with reactive oxygen species (ROS) for the transmission of a stress signal. This study investigated the influence of variations in calcium concentrations on plant defense signaling and photosynthetic acclimatization after mechanical damage. Solanum lycopersicum Micro-Tom was grown with 0, 2 and 4 mM Ca2+, with and without mechanical damage. The expression of stress genes was evaluated, along with levels of antioxidant enzymes, hydrogen peroxide, lipid peroxidation, histochemistry, photosynthesis and dry mass of organs. The ROS production generated by mechanical damage was further enhanced by calcium-free conditions due to the inactivation of the oxygen evolution complex, contributing to an increase in reactive species. The results indicated that ROS affected mechanical damage signaling because calcium-free plants exhibited high levels of H2O2 and enhanced expression of kinase and RBOH1 genes, necessary conditions for an efficient response to stress. We conclude that the plants without calcium supply recognized mechanical damage but did not survive. The highest expression of the RBOH1 gene and the accumulation of H2O2 in these plants signaled cell death. Plants grown in the presence of calcium showed higher expression of SlCaM2 and control of H2O2 concentration, thus overcoming the stress caused by mechanical damage, with photosynthetic acclimatization and without damage to dry mass production.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/metabolismo , Peróxido de Hidrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sinalização do Cálcio , Fotossíntese/genética , Aclimatação , Antioxidantes/metabolismo , Expressão Gênica , Folhas de Planta/metabolismo
5.
Environ Manage ; 70(6): 978-989, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36036277

RESUMO

Species distribution patterns are widely used to guide conservation planning and are a central issue in ecology. The usefulness of spatial correlation analysis has been highlighted in several ecological applications so far. However, spatial assumptions in ecology are highly scale-dependent, in which geographical relationships between species diversity and distributions can have different conservation concerns. Here, an integrative landscape planning was designed to show the spatial distribution patterns of taxonomic and functional diversity of amphibians and fishes, from multiple species traits regarding morphology, life history, and behavior. We used spatial, morphological, and ecological data of amphibians and fishes to calculate the functional diversity and the spatial correlation of species. Mapping results show that the higher taxonomic and functional diversity of fishes is concentrated in the West Atlantic Forest. Considering amphibians, are located in the East portion of the biome. The spatial correlation of species indicates the regions of the Serra do Mar and the extreme southern part of the Central Corridor as the main overlapped species distribution areas between both groups. New key conservation sites were reported within the Brazilian Atlantic Forest hotspot, revealing cross-taxon mismatches between terrestrial and freshwater ecosystems. This study offers useful spatial information integrating suitable habitats of fishes and amphibians to complement existing and future research based on terrestrial and freshwater conservation. New priorities for biodiversity conservation in rich-species regions highlight the importance of spatial pattern analysis to support land-use planning in a macroecological context.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Conservação dos Recursos Naturais/métodos , Anfíbios , Biodiversidade , Peixes
6.
Rev Med Chil ; 150(3): 391-396, 2022 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-36156724

RESUMO

BACKGROUND: Clinical Ethics Committees are deliberative groups whose main functions are to assess cases with ethical-clinical conflicts, to generate institutional protocols for preventive purposes, and to train health teams. AIM: To analyze the activity of a clinical ethics committee of a general hospital in the period 2007-2020. MATERIAL AND METHODS: A retrospective analysis of all session records, annual reports, case resolution and documents generated by the Clinical Ethics Committee of Carlos van Buren Hospital in Valparaíso, Chile, between 2007 and 2020, was carried out. RESULTS: On average, 12 cases are analyzed per year. Sixty percent correspond to requests from pediatric units and in 78% of these cases there was at least one neurological disease. In 62% of cases, the main ethical dilemma was adequacy of therapeutic effort, followed by dilemmas related to the exercise of autonomy in 18.2%. In education, two courses are identified aimed to doctors, residents, and other members of the health team. Regarding normative functions, several documents were generated at the request of the Hospital management or in different clinical situations. During COVID-19 pandemia, the active role of the committee was linked to the three main functions, namely evaluating cases, participating in morbidity and mortality meetings for preventive purposes, and issuing guidelines and recommendations for action. The active participation of Pediatric Neurology residents in the Committee, for educational and administrative purposes, stands out. CONCLUSIONS: The three main functions described for the ethics committees were exerted by this Committee during the evaluated period. The impact of our recommendations remain to be objectively evaluated.


Assuntos
COVID-19 , Comitês de Ética Clínica , Criança , Comissão de Ética , Hospitais Gerais , Humanos , Estudos Retrospectivos
7.
BMC Pediatr ; 21(1): 26, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33413191

RESUMO

BACKGROUND: Evaluating blood pressure (BP) is one element for diagnosing and preventing disease in student populations. The objectives of this research were to (a) identify the range of height for measuring BP adjusted for student populations and (b) propose percentiles for evaluating BP based on height. METHODS: A cross-sectional study was carried out with 3,013 students. Weight, height, and diastolic (DBP) and systolic (SBP) blood pressure were evaluated. Body Mass Index (BMI) was calculated. Height ranges of 5 and 10 cm were generated. RESULTS: R2 values for height ranges of 5 cm consisted of [normotensive: DBP (R2 = 10 to 13%) and SBP (R2 = 14 to 20%), and for hypertensive: DBP (R2 = 0.07 to 15%) and for SBP (R2 = 29 to 32%)]. For height ranges of 10 cm, values included: [normotensive: DBP (R2 = 10 to 15%), and SBP (R2 = 15 to 21%) and for hypertensive: DBP (R2 = 0.07 to 16%) and SBP (R2 = 29 to 35%)]. For 5 cm height ranges, diferences occurred between both sexes for DBP (in 5 height ranges from 123 to 148 cm and 158 to 168 cm) and for the SBP (in 6 height ranges from 128 to 148 cm and from 158 to 168 cm). In the 10 cm categories, diferences appeared in DBP (from 138 to 148 cm) and in the SBP (from 158 to 168 cm). CONCLUSIONS: Height is a determinant for evaluating blood pressure, and height ranges of 10 cm are more suitable for children and adolescents. The proposed percentiles based on height ranges allowed assessment of the DBP and SBP suggest their use in epidemiological and educational contexts.


Assuntos
Hipertensão , Adolescente , Pressão Sanguínea , Estatura , Índice de Massa Corporal , Peso Corporal , Criança , Estudos Transversais , Feminino , Humanos , Hipertensão/diagnóstico , Masculino
8.
J Oral Maxillofac Surg ; 79(2): 473.e1-473.e7, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33137301

RESUMO

PURPOSE: A variety of techniques have been described in the literature for the treatment of temporomandibular joint ankylosis. However, 1 of the factors most commonly related to the failure of maintenance mouth opening in the postoperative period is the inadequate excision of the ankylotic mass. Furthermore, the surrounding noble structures, such as the base of the skull, internal maxillary artery, and dental germs, are at risk of being affected during the procedure. MATERIALS AND METHODS: For this reason, prototyped guides have been proposed to steer osteotomies and resections of the ankylotic block in the temporomandibular joint. RESULTS: Nevertheless, access to this technology, especially in developing countries, can represent a financial barrier. CONCLUSION: Therefore, our proposal is to manufacture low-cost surgical cutting guides to increase their applicability.


Assuntos
Anquilose , Transtornos da Articulação Temporomandibular , Anquilose/cirurgia , Artroplastia , Criança , Humanos , Osteotomia , Articulação Temporomandibular/cirurgia , Transtornos da Articulação Temporomandibular/cirurgia
9.
Environ Monit Assess ; 193(9): 547, 2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34341861

RESUMO

Assessing carbon storage and sequestration is key for defining effective conservation actions to mitigate climate change. Forest species changes have direct impacts on carbon stocks and may lead to undesirable climate trade-offs. In this paper, we measure aboveground biomass (AGB) and the impact of forest changes on climate regulation through three land policy scenarios by 2030 in continental Portugal. We found that a High intervention scenario, supported by an important increase in "Other coniferous trees" class, will provide 29.5% more of carbon sequestration, whereas a Low intervention scenario, in which there is a moderate increase in all forest classes, will result in an increase of 5.7%. A business as usual (BAU) scenario, supported by an increase in eucalyptus forests and a decrease in autochthonous species, will decrease carbon sequestration (-2.7%), particularly Lisboa, Algarve and North regions. Economic valuation shows that the High intervention scenario will generate the highest economic outcome for climate regulation by 2030. This study provides a spatial-based methodology for monitoring carbon sequestration and new insights about the impact of policies for Green House Gas (GHG) mitigation, supporting the 2030 Sustainable Development Goals achievement.


Assuntos
Sequestro de Carbono , Monitoramento Ambiental , Biomassa , Carbono/análise , Mudança Climática , Conservação dos Recursos Naturais , Florestas , Portugal , Árvores
10.
Sensors (Basel) ; 20(14)2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32668609

RESUMO

Some robotic localization methods, such as ultra wideband localization and lighthouse localization, require external localization infrastructure in order to operate. However, there are situations where this localization infrastructure does not exist in the field, such as robotic exploration tasks. Deploying low power wireless sensor networks (WSNs) as localization infrastructure can potentially solve this problem. In this work, we demonstrate the use of an OpenWSN network of miniaturized low power sensor nodes as localization infrastructure. We demonstrate a quadrotor performing laser-based relative bearing measurements of stationary wireless sensor nodes with known locations and using these measurements to localize itself. These laser-based measurements require little computation on the WSN nodes, and are compatible with state-of-the-art 2 mm × 3 mm monolithic wireless system-on-chips (SoCs). These capabilities were demonstrated on a Crazyflie quadcopter using an Extended Kalman Filter and a network of motes running the OpenWSN wireless sensor network stack. The RMS error for X positioning was 0.57 m and the error for Y positioning was 0.39 m. This is the first use of an OpenWSN sensor network to support robotic localization. Furthermore, simulations show that these same measurements could be used for localizing sensor motes with unknown locations in the future.

11.
Environ Manage ; 65(1): 46-61, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31832730

RESUMO

Ecological connectivity depends on key elements within the landscape, which can support ecological fluxes, species richness and long-term viability of a biological community. Landscape planning requires clear aims and quantitative approaches to identify which key elements can reinforce the spatial coherence of protected areas design. We aim to explore the probability of the ecological connectivity of forest remnants and amphibian species distributions for current and future climate scenarios across the Central Corridor of the Brazilian Atlantic Forest. Integrating amphibian conservation, climate change and ecological corridors, we design a landscape ranking based on graph and circuit theories. To identify the sensitivity of connected areas to climate-dependent changes, we use the Model for Interdisciplinary Research on Climate by means of simulations for 2080-2100, representing a moderated emission scenario within an optimistic context. Our findings indicate that more than 70% of forest connectivity loss by climate change may drastically reduce amphibian dispersal in this region. We show that high amphibian turnover rates tend to be greater in the north-eastern edges of the corridor across ensembles of forecasts. Our spatial analysis reveals a general pattern of low-conductance areas in landscape surface, yet with some well-connected patches suggesting potential ecological corridors. Atlantic Forest reserves are expected to be less effective in a near future. For improved conservation outcomes, we recommend some landscape paths with low resistance values across space and time. We highlight the importance of maintaining forest remnants in the southern Bahia region by drafting a blueprint for functional biodiversity corridors.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Anfíbios , Animais , Biodiversidade , Brasil , Ecossistema
12.
Am J Ind Med ; 61(7): 547-555, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29608217

RESUMO

BACKGROUND: In Brazil, underreporting of mesothelioma and cancer of the pleura (MCP) is suspected to be high. Records from death certificates (SIM) and hospital registers (SIH-SUS) can be combined to recover missing data but only anonymous databases are available. This study shows how common data can be used for linkage and as an assessment of accuracy. METHODS: Mesothelioma (all sites, ICD-10 codes C45.0-C45.9) and cancer of the pleura (C38.4) were retrieved from both information systems and combined using a linkage algorithm. Accuracy was examined with non-anonymous databases, limited to the state of São Paulo. RESULTS: We found 775 cases in death certificates and 283 in hospital registers. The linkage matched 57 cases, all accurately paired. Three cases, 0.4% in SIM and 1.3% in SIH-SUS, could not be matched because of data inconsistencies. CONCLUSIONS: A computer linkage can recover MCP cases from hospital records not found in death certificates in Brazil.


Assuntos
Atestado de Óbito , Neoplasias Cardíacas/mortalidade , Registros Hospitalares , Mesotelioma/mortalidade , Neoplasias Peritoneais/mortalidade , Neoplasias Pleurais/mortalidade , Adulto , Idoso , Algoritmos , Brasil , Causas de Morte , Coleta de Dados , Feminino , Sistemas de Informação em Saúde , Humanos , Armazenamento e Recuperação da Informação , Masculino , Pessoa de Meia-Idade , Pericárdio
13.
Rev Med Chil ; 144(2): 262-6, 2016 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-27092683

RESUMO

Chronic eosinophilic pneumonia (CEP) is uncommon and predominantly seen in women. More than 6% of eosinophils in peripheral blood and more than 25% in bronchoalveolar lavage are diagnostic criteria. Secondary causes of hypereosinophilic pneumonia must be ruled out. We report a 72-year-old non-smoker man presenting in the emergency room with a history of cough, fever, and moderate dyspnea. He was not taking any medication. A chest-X ray showed a left lower lobe (LLL) consolidation, and was started on broad-spectrum antibiotics with a presumptive diagnosis of pneumonia. There was no improvement after therapy. A chest CT scan showed increased LLL consolidation and new left upper lobe ground glass opacities as well as a moderate left pleural effusion. Flexible bronchoscopy was performed and bronchoalveolar lavage showed 95% eosinophils, and had negative cultures. No parasites were identified. Transbronchial biopsies demonstrated eosinophil accumulation in alveoli and interstitium and pleural fluid was composed by 85% eosinophils. With the diagnosis of CEP, systemic corticosteroids were used with favorable clinical and radiological response.


Assuntos
Eosinofilia Pulmonar/diagnóstico , Idoso , Biópsia , Doença Crônica , Humanos , Masculino , Tomografia Computadorizada por Raios X
14.
Clin Oral Implants Res ; 26(11): 1256-60, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24995491

RESUMO

OBJECTIVES: The objective of this histologic study was to determine the effect of three drilling protocols (oversized, intermediate, and undersized) on biologic responses to a single implant type at early healing periods (2 weeks in vivo) in a beagle dog model. MATERIALS AND METHODS: Ten beagle dogs were acquired and subjected to surgeries in the tibia 2 weeks before euthanasia. During surgery, each dog received three Unitite implants, 4 mm in diameter by 10 mm in length, in bone sites drilled to 3.5, 3.75, and 4.0 mm in final diameter. The insertion torque was recorded during surgery, and bone-to-implant contact (BIC), and bone area fraction occupied (BAFO) measured from the histology. Each outcome measure was compared between treatment conditions with the Wilcoxon signed-rank test. Bonferroni-corrected statistical significance was set to 95%. RESULTS: Insertion torque increased as an inverse function of drilling diameter, as indicated by significant differences in torque levels between each pair of conditions (P = 0.005). BIC and BAFO levels were highest and statistically similar in the recommended and undersized conditions and significantly reduced in the oversized condition (P < 0.01). CONCLUSIONS: Reduced drilling dimensions resulted in increased insertion torque (primary stability). While BIC and BAFO were maximized when drilling the recommended diameter hole, only the oversized hole resulted in evidence of statistically reduced integration.


Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Torque , Animais , Remodelação Óssea , Cães , Modelos Animais , Cicatrização
15.
Med Oral Patol Oral Cir Bucal ; 20(4): e471-9, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25858087

RESUMO

BACKGROUND: This study histologically evaluated two implant designs: a classic thread design versus another specifically designed for healing chamber formation placed with two drilling protocols. STUDY DESIGN: Forty dental implants (4.1 mm diameter) with two different macrogeometries were inserted in the tibia of 10 Beagle dogs, and maximum insertion torque was recorded. Drilling techniques were: until 3.75 mm (regular-group); and until 4.0 mm diameter (overdrilling-group) for both implant designs. At 2 and 4 weeks, samples were retrieved and processed for histomorphometric analysis. For torque and BIC (bone-to-implant contact) and BAFO (bone area fraction occupied), a general-linear model was employed including instrumentation technique and time in vivo as independent. RESULTS: The insertion torque recorded for each implant design and drilling group significantly decreased as a function of increasing drilling diameter for both implant designs (p<0.001). No significant differences were detected between implant designs for each drilling technique (p>0.18). A significant increase in BIC was observed from 2 to 4 weeks for both implants placed with the overdrilling technique (p<0.03) only, but not for those placed in the 3.75 mm drilling sites (p>0.32). CONCLUSIONS: Despite the differences between implant designs and drilling technique an intramembranous-like healing mode with newly formed woven bone prevailed.


Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Osseointegração , Animais , Cães , Masculino , Modelos Animais
16.
An Acad Bras Cienc ; 86(4): 1873-86, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25590723

RESUMO

The number of papers on biology of amphibians has increased in the recent years. A detailed overview of the publications on amphibians can be very useful in assessing the status of our knowledge about this taxonomic group. Due to the large number of articles published, we aimed to assess the scientific contribution of herpetological researches carried out between the years 2001 and 2010 on Brazilian amphibians, considering the diversity patterns, the threats and the research topics that have been published most often. We applied scientometric attention indexes in the reviewed studies from seven scientific databases. To examine the relationship between the numbers of species recorded locally and regionally at different spatial scales, we used an additive partitioning of diversity in three hierarchical levels (i.e., states, geographic regions and biomes). We evaluated 892 articles and 914 species, which showed that 65 % of the total diversity of Brazilian amphibian species was represented by the beta diversity among the biomes. We identified many differences in the allocation of research efforts for taxonomic groups, threats categories, geographic regions, and research topics, highlighting the main research trends conducted and the priority themes for investigation of further papers on Brazilian amphibians.


Assuntos
Anfíbios/classificação , Biodiversidade , Conservação dos Recursos Naturais , Animais , Brasil , Densidade Demográfica , Dinâmica Populacional
17.
Mar Environ Res ; 198: 106563, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38801786

RESUMO

The Amazon Reef System (ARS) is one of the most important shallow and mesophotic reef ecosystems in the South Atlantic Ocean. The ARS consists mainly of extensive beds of calcareous algae interspersed by assemblages of octocorals and sponges. The enormous freshwater discharge from the Amazon River forms a plume along the extensive Amazon continental shelf, for which the hydroid community is still largely unknown. The aim of this study is to document the diversity and distribution of hydroids from the ARS, as well as to infer the influence of the plume on species composition in the different zones. Samples were collected at ninety-six stations between 15 and 240 m deep on the Amazon shelf. A total of 37 species were recorded in the studied area. Hydroid assemblages are richer in zones under lower river plume influence, and species composition differs significantly between zones with and without plume influence (PERMANOVA, p = 0.0025). The dissolved oxygen and nitrate ranges were the environmental variables significantly correlated with the hydroid distribution. This study is the first surveying the hydroid species composition and richness in the ARS, highlighting the presence of a typical reef biota and that further faunal studies in underexplored areas of the Atlantic should reveal the distribution of many poorly known hydroids species.


Assuntos
Biodiversidade , Recifes de Corais , Monitoramento Ambiental , Rios , Brasil , Animais , Oceano Atlântico , Ecossistema
18.
Poult Sci ; 103(9): 103986, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-39003795

RESUMO

Necrotic enteritis (NE) is a disease of worldwide distribution, which affects young broilers and causes economic losses on a scale of 6 billion dollars per year. For decades, NE was controlled in poultry flocks by dietary administration of low doses of antimicrobial growth promoters (AGPs). However, an increase in NE incidence was noted after the AGP ban. This study aimed to compare the effect of an antibiotic (Enramycin) diet to a combination of sodium butyrate, hydrolyzed yeast, and zinc proteinate (ViligenTM) on broiler diets regarding performance, blood parameters, intestinal permeability, morphology and lesions, and carcass yield of broilers challenged with Eimeria spp. and Clostridium perfringens to simulate subclinical necrotic enteritis. A total of 1,150 one-day-old male broiler chickens with an initial average weight of 43.9 ± 0.65 g were allocated to 50 experimental pens. Animals were divided into 5 groups: Negative control (NC) without additives; Positive control (PC) with 0.12 g/ton of Enramycin (8%); V500, V1000, and V1500 with the addition of 500, 1.000, and 1.500 g/ton of Viligen, respectively. All animals were challenged by Eimeria spp. at 7 d of age and by C. perfringens at 17, 18, and 19 d for induction of subclinical NE. The broilers fed with all concentrations of Viligen showed similar performance, blood parameters, intestinal permeability, and carcass yield compared to PC broilers. However, NC broilers showed higher FCR compared to PC broilers from 1 to 33 d (1.42 vs. 1.39) (P = 0.048) and from 1 to 42 d (1.51 vs. 1.49) (P < 0.001). V1500 broilers had fewer intestinal lesions at 28 d when compared to the PC treatment (P < 0.05) and showed that higher Viligen inclusion resulted in lower intestinal damage. At 21 d, the V500 group showed higher intestinal morphology characteristics (VH:VD 4.9 vs. 3.5) compared to the PC treatment (P < 0.001). Thus, in this study, the dietary addition of Viligen to broilers challenged by an experimental model of subclinical NE resulted in lower intestinal damage and similar performance to that obtained by the addition of Enramycin.

19.
J Oral Maxillofac Surg ; 71(2): e69-75, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23351770

RESUMO

PURPOSE: The present study evaluated the effect of different drilling dimensions (undersized, regular, and oversized) in the insertion and removal torques of dental implants in a beagle dog model. METHODS: Six beagle dogs were acquired and subjected to bilateral surgeries in the radii 1 and 3 weeks before euthanasia. During surgery, 3 implants, 4 mm in diameter by 10 mm in length, were placed in bone sites drilled to 3.2 mm, 3.5 mm, and 3.8 mm in final diameter. The insertion and removal torque was recorded for all samples. Statistical analysis was performed by paired t tests for repeated measures and by t tests assuming unequal variances (all at the 95% level of significance). RESULTS: Overall, the insertion torque and removal torque levels obtained were inversely proportional to the drilling dimension, with a significant difference detected between the 3.2 mm and 3.5 mm relative to the 3.8 mm groups (P < 0.03). Although insertion torque-removal torque paired observations was statistically maintained for the 3.5 mm and 3.8 mm groups, a significant decrease in removal torque values relative to insertion torque levels was observed for the 3.2 mm group. A different pattern of healing and interfacial remodeling was observed for the different groups. CONCLUSIONS: Different drilling dimensions resulted in variations in insertion torque values (primary stability) and stability maintenance over the first weeks of bone healing.


Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Retenção em Prótese Dentária , Animais , Fenômenos Biomecânicos , Implantação Dentária Endóssea/instrumentação , Planejamento de Prótese Dentária , Cães , Masculino , Modelos Animais , Osseointegração/fisiologia , Osteotomia/instrumentação , Estresse Mecânico , Propriedades de Superfície , Tíbia/cirurgia , Fatores de Tempo , Torque
20.
J Am Coll Radiol ; 20(11): 1177-1187, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37634794

RESUMO

PURPOSE: The purpose of this study was to use a discrete-choice experiment to model the trade-offs evaluators make between academic attributes and demographics when the United States Medical Licensing Examination (USMLE) Step 1 switches to pass/fail. METHODS: A discrete-choice experiment was administered to faculty members from a geographically diverse mix of 14 academic and community radiology departments in the United States from August through November 2020. Reviewers reviewed 10 applicant pairs with numeric Step 1 scores (part 1) and 10 applicant pairs with a pass Step 1 result (part 2). Applicant attributes included medical school rank, gender, race/ethnicity, USMLE Step 1 score, USMLE Step 2 score, class rank, clerkship honors, and publications. Conditional logistic regression modeled the influence of attribute levels. RESULTS: Two hundred twelve evaluators completed the study (response rate 59%). The most influential attribute was Step 1 score in part 1 and medical school rank in part 2. The relative importance of race/ethnicity and gender decreased by 25% and 29%, respectively, when Step 1 switches to pass/fail. Evaluators weigh race/ethnicity the strongest when applicants have the same Step 1 score (preference weights of 0.85 for African American, 1.42 for Hispanic, and 0 for White and Asian applicants). Race/ethnicity is relatively more important when Step 1 scores are higher (preference weights of 1.58 for African American, 0.90 for Hispanic, and 0 for White and Asian applicants). CONCLUSIONS: The loss of numeric Step 1 scores reduced the residency evaluator preference for diversity. Reviewers prioritize underrepresented-in-medicine applicants when Step 1 scores are higher and comparable with White and Asian applicants.


Assuntos
Avaliação Educacional , Internato e Residência , Licenciamento , Medicina , Humanos , Negro ou Afro-Americano , Etnicidade , Hispânico ou Latino , Estados Unidos , Diversidade, Equidade, Inclusão
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