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1.
PeerJ ; 12: e17428, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38881861

RESUMO

Background: Patients in serious condition due to COVID-19 often require special care in intensive care units (ICUs). This disease has affected over 758 million people and resulted in 6.8 million deaths worldwide. Additionally, the progression of the disease may vary from individual to individual, that is, it is essential to identify the clinical parameters that indicate a good prognosis for the patient. Machine learning (ML) algorithms have been used for analyzing complex medical data and identifying prognostic indicators. However, there is still an urgent need for a model to elucidate the predictors related to patient outcomes. Therefore, this research aimed to verify, through ML, the variables involved in the discharge of patients admitted to the ICU due to COVID-19. Methods: In this study, 126 variables were collected with information on demography, hospital length stay and outcome, chronic diseases and tumors, comorbidities and risk factors, complications and adverse events, health care, and vital indicators of patients admitted to an ICU in southern Brazil. These variables were filtered and then selected by a ML algorithm known as decision trees to identify the optimal set of variables for predicting patient discharge using logistic regression. Finally, a confusion matrix was performed to evaluate the model's performance for the selected variables. Results: Of the 532 patients evaluated, 180 were discharged: female (16.92%), with a central venous catheter (23.68%), with a bladder catheter (26.13%), and with an average of 8.46- and 23.65-days using bladder catheter and submitted to mechanical ventilation, respectively. In addition, the chances of discharge increase by 14% for each additional day in the hospital, by 136% for female patients, 716% when there is no bladder catheter, and 737% when no central venous catheter is used. However, the chances of discharge decrease by 3% for each additional year of age and by 9% for each other day of mechanical ventilation. The performance of the training data presented a balanced accuracy of 0.81, sensitivity of 0.74, specificity of 0.88, and the kappa value was 0.64. The test performance had a balanced accuracy of 0.85, sensitivity 0.75, specificity 0.95, and kappa value of 0.73. The McNemar test found that there were no significant differences in the error rates in the training and test data, suggesting good classification. This work showed that female, the absence of a central venous catheter and bladder catheter, shorter mechanical ventilation, and bladder catheter duration were associated with a greater chance of hospital discharge. These results may help develop measures that lead to a good prognosis for the patient.


Assuntos
COVID-19 , Unidades de Terapia Intensiva , Aprendizado de Máquina , SARS-CoV-2 , Humanos , COVID-19/mortalidade , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Brasil/epidemiologia , Idoso , Fatores de Proteção , Adulto , Fatores de Risco , Prognóstico , Alta do Paciente/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos
2.
Sci Total Environ ; 882: 163503, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37076012

RESUMO

Tropical montane forests (TMF) of the threatened Atlantic Forest hotspot play an important role in providing essential ecosystem services associated with hydrological regime and biodiversity conservation. However, important ecological patterns such as those related to the woody carbon biogeochemical cycle are not yet known for these forests, especially those located at high elevations (> 1500 m. a.s.l.). Herein, we used a dataset of 60 plots (2.4 ha) of old-growth TMF sampled along a high-elevation gradient (1500-2100 m a.s.l.) and monitored in two inventories (2011 and 2016) to better understand the patterns of carbon stock and uptake of these high-elevation forests and the related environmental (soil) and elevation controls. We found differences in the carbon stock along different elevation levels (120.36-170.4C.ton.ha-1) and a carbon accumulation trend over the period along the entire gradient. Thus, forest carbon gain (3.82-5.14 ton.ha.year-1) was greater than the carbon loss (2.1-3.4 ton.ha.year-1) and resulted in a positive productivity net. In other words, the TMF acted as a carbon sink, removing carbon from the atmosphere and storing it in woody tissues. Soil variables also exert significant influences on carbon stock and uptake (significative effects of phosphorus on carbon stock and of cation exchange capacity on carbon loss), driving such patterns in isolation or in interaction with elevation. Considering the high conservation degree of the TMF monitored, our results may be indicative of a similar trend in other similar forests, but which have gone through disturbances in the more recent past. These TMF fragments have a wide occurrence in the Atlantic Forest hotspot and may also be acting or will soon act as carbon sinks in improved conservation scenarios. Thus, these forests can play an essential role in conserving ecosystem services in the region and in mitigating climate changes.


Assuntos
Carbono , Ecossistema , Florestas , Madeira , Sequestro de Carbono , Solo , Clima Tropical , Árvores , Biomassa
3.
Sci Adv ; 8(24): eabl7968, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35714191

RESUMO

Understanding the mechanisms controlling forest carbon storage is crucial to support "nature-based" solutions for climate change mitigation. We used a dataset of 892 Atlantic Forest inventories to assess the direct and indirect effects of environmental conditions, human impacts, tree community proprieties, and sampling methods on tree above-ground carbon stocks. We showed that the widely accepted drivers of carbon stocks, such as climate, soil, topography, and forest fragmentation, have a much smaller role than the forest disturbance history and functional proprieties of the Atlantic Forest. Specifically, within-forest disturbance level was the most important driver, with effect at least 30% higher than any of the environmental conditions individually. Thus, our findings suggest that the conservation of tropical carbon stocks may be dependable on, principally, avoiding forest degradation and that conservation policies focusing only on carbon may fail to protect tropical biodiversity.

4.
Ultrasonics ; 119: 106582, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34600427

RESUMO

For the first time, the 9% Ni steel is being used in CO2 injection units in floating production storage offloading vessels. Pipe joints welded with nickel-based superalloy 625 as the filler metal present difficulties in ultrasonic inspection owing to the sonic attenuation and deviation caused by the anisotropic and coarse-grained weld metal. This study aims to conduct a probability of detection (POD) to evaluate the discontinuity detection reliability in 9% Ni steel arc welded joints. The inspections were performed using ultrasonic phased array transducers with transversal and longitudinal waves, by using both a conventional wedge formed of Rexolite® and an adapted wedge filled with water to simulate the immersion inspection. POD curves were developed using the hit/miss and â vs a models. The inspection performed with transversal waves detected much fewer discontinuities than that performed with longitudinal waves. Furthermore, inspection performed with longitudinal waves after weld metal cap pass removal exhibited much more reliability in 9% Ni steel welded joints. The obtained POD curves were shown to be a suitable tool to evaluate the inspection of 9% Ni steel welded joints, as they confirmed that the best inspection procedure involves a combination of three different phased array ultrasonic testing configurations.

5.
Clin. biomed. res ; 42(4): 389-396, 2022.
Artigo em Português | LILACS | ID: biblio-1516184

RESUMO

Este estudo teve por objetivo reunir evidências científicas sobre o papel dos fatores sociodemográficos na adesão aos anti-hipertensivos na Atenção Primária à Saúde (APS) no Brasil. Trata-se de uma revisão integrativa com estudos publicados entre 2015 e 2019 em periódicos nacionais. Foram incluídos artigos originais desenvolvidos com hipertensos usuários da APS no Brasil e foram excluídos artigos publicados fora do intervalo temporal citado, bem como revisões de literatura, e os que não tinham como foco os elementos de interesse nesta revisão. Foram selecionados 5 estudos que investigaram variáveis sociodemográficas no contexto da adesão a esta classe de medicamentos na APS. Embora alguns estudos tenham encontrado uma possível interferência de algumas variáveis sociodemográficas na adesão aos anti-hipertensivos na Atenção Básica, há, para cada uma dessas variáveis, resultados divergentes, mostrando que a dimensão sociodemográfica pode ou não interferir na adesão à medicação em um determinado grupo populacional. Nesse sentido, há também resultados sugestivos de que, com oferta efetiva de assistência aos usuários, tais variáveis parecem perderem capacidade de interferirem nesta adesão, em consonância com a hipótese de que características organizacionais dos serviços de saúde têm impacto muito maior na adesão do que diferenças sociodemográficas.


This study aimed to gather scientific evidence on the role of sociodemographic factors in adherence to antihypertensive drugs in Primary Health Care (PHC)_in Brazil. This is an integrative review with studies published between 2015 and 2019 in national journals. Original studies developed with hypertensive PHC users in Brazil were included and articles published outside the time range were excluded, as well as literature reviews, and those that did not focus on the elements of interest of this review. A total of 5 studies that investigated sociodemographic variables in the context of adherence to this class of drugs in PHC were selected. Although some studies have found a possible interference of some sociodemographic variables in adherence to antihypertensive drugs in Primary Care, there are, for each of these variables, divergent results, showing that the sociodemographic dimension may or may not interfere with medication adherence in a given population group. In this sense, there are also results suggesting that, with effective provision of assistance to users, such variables seem to lose their interference capacity in user adherence, in line with the hypothesis that organizational characteristics of health services have a much greater impact on adherence than sociodemographic differences.


Assuntos
Humanos , Idoso , Idoso de 80 Anos ou mais , Adesão à Medicação/estatística & dados numéricos , Anti-Hipertensivos/uso terapêutico , Hipertensão/prevenção & controle , Hipertensão/tratamento farmacológico
6.
MethodsX ; 8: 101449, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34430334

RESUMO

This article presents a methodology to classify the polarity of words from selected Tweets. Usually, social media sentiment (SMS) is lexically determined, manually or by machine learning. However, these methods are either slow or based on a pre-established dictionary, thus not providing a customised analysis. We propose a methodology that, after having mined the topic-related Tweets, filters relevant words based on the mean and standard deviation frequency in positive and negative market days to remove neutral terms. Subsequently, through an ad hoc perceptual mapping, we assign a polarity to the dataset. This method allows the building of a dictionary associated with the investor sentiment customised to that organisation. A practical application was carried out to test the proposed methodology. The results were significant and in line with the behavioural finance theory, confirming that irrational investor feelings-expressed via social media-drive a portion of asset prices. Results also confirm the investor asymmetric behaviour under gain or loss scenarios, with the latter generating more impact than the former because people are risk-averse. The proposed method is expected to identify patterns of behaviour in social media linked to market oscillations, thereby contributing to risk management and optimising decision-making in the stock market.•The use of both statistical and perceptual map filters allows a specific asset dictionary to be built;•Textual sentiment analysis based on social media;•The proposed method efficiently overcomes generic dictionaries and language issues.

7.
Clin Adv Periodontics ; 11(3): 150-154, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33527757

RESUMO

INTRODUCTION: The remaining epithelial layer existent in connective tissue graft (CTG) harvested from the hard palate, which underwent de-epithelization outside the oral cavity, can be histologically detected unless it is completely removed. Its presence may cause adverse esthetics results, affecting thus the color and texture of the receptor site, and an increased risk of presence of scar tissues after surgical procedures. The proposal of this study was to evaluate the CTG (histological and morphometrically) collected from the hard palate using the Harris technique, removing the epithelial layer outside the mouth, assessing the remaining presence of epithelial tissue. CASE SERIES: Fourteen patients (14 CTGs) were included in the present case series study, therefore there were two dropouts. A small part of the tip of the graft was harvested and fixed in formalin solution for histological processing, staining, and then to be morphometrically analyzed. The epithelial tissue and CTGs were assessed by three calibrated and double-blinded professionals. All information was compiled, and the statistical analysis was performed. CTGs obtained had a width average of 1224.26 µm. There was no presence of any residual of the epithelium in three samples, whereas only one had the epithelium tissue covering the entire connective layer. Furthermore, seven samples (approximately 50%) had the presence of epithelium. CONCLUSION: Within the limitation of this study, there was incomplete removal of the epithelial layer after harvesting the CTG using the Harris technique (44.32%), most likely due to its histological persistency, suggesting to be inaccurate the clinical removal.


Assuntos
Retração Gengival , Transplantes , Tecido Conjuntivo , Estética Dentária , Gengiva , Humanos
8.
Sci Adv ; 6(51)2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33355136

RESUMO

Tropical forests have played an important role as a carbon sink over time. However, the carbon dynamics of Brazilian non-Amazon tropical forests are still not well understood. Here, we used data from 32 tropical seasonal forest sites, monitored from 1987 to 2020 (mean site monitoring length, ~15 years) to investigate their long-term trends in carbon stocks and sinks. Our results highlight a long-term decline in the net carbon sink (0.13 Mg C ha-1 year-1) caused by decreasing carbon gains (2.6% by year) and increasing carbon losses (3.4% by year). The driest and warmest sites are experiencing the most severe carbon sink decline and have already moved from carbon sinks to carbon sources. Because of the importance of the terrestrial carbon sink for the global climate, policies are needed to mitigate the emission of greenhouse gases and to restore and protect tropical seasonal forests.

9.
Front Plant Sci ; 11: 1113, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849685

RESUMO

The projected impact of global warming on coffee production may require the heat-adapted genotypes in the next decades. To identify cellular strategies in response to warmer temperatures, we compared the effect of elevated temperature on two commercial Coffea arabica L. genotypes exploring leaf physiology, transcriptome, and carbohydrate/protein composition. Growth temperatures were 23/19°C (day/night), as optimal condition (OpT), and 30/26°C (day/night) as a possible warmer scenario (WaT). The cv. Acauã showed lower levels of leaf temperature (Tleaf) under both conditions compared to cv. Catuaí, whereas slightly or no differences for other leaf physiological parameters. Therefore, to explore temperature responsive pathways the leaf transcriptome was examined using RNAseq. Genotypes showed a marked number of differentially-expressed genes (DEGs) under OpT, however DEGs strongly decrease in both at WaT condition indicating a transcriptional constraint. DEGs responsive to WaT revealed shared and genotype-specific genes mostly related to carbohydrate metabolism. Under OpT, leaf starch content was greater in cv. Acauã and, as WaT temperature was imposed, the leaf soluble sugar did not change in contrast to cv. Catuaí, although the levels of leaf starch, sucrose, and leaf protein decreased in both genotypes. These findings revealed intraspecific differences in the underlying transcriptional and metabolic interconnected pathways responsive to warmer temperatures, which is potentially linked to thermotolerance, and thus may be useful as biomarkers in breeding for a changing climate.

10.
Materials (Basel) ; 13(4)2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32098044

RESUMO

This work aims to compare the ultrasonic inspection of 9%Ni steel joints welded with the Gas Metal Arc Welding (GMAW) process and Shielded Metal Arc Welding (SMAW) process. These are the two most widely used processes used to weld pipes for CO2 injection units for floating production storage and offloading (FPSO) in the Brazilian oil and gas industry. The SMAW equipment is simple and portable, which is convenient for the FPSO; however, the GMAW process has the advantage of welding with high productivity. In this study we performed a numerical simulation using the software CIVA, 11th version, to analyze the behavior of ultrasonic longitudinal wave beams through GMAW and SMAW dissimilar weld joints. Ultrasonic tests were performed on calibration blocks drawn from both welded joints to evaluate the simulation results. The results are discussed with regard to the microstructure of the weld metal via electron backscatter diffraction (EBSD) analyses. The SMAW process presented better inspection performance than the GMAW process in terms of attenuation and dispersion effects. Although the SMAW had a better outcome, for both processes the configuration of 16 active elements and a scanning angle of 48° resulted in an optimized inspection of the entire joint.

11.
Rev. bras. odontol ; 72(1/2): 92-95, Jan.-Jun. 2015. ilus
Artigo em Português | LILACS | ID: lil-792066

RESUMO

A evolução do projeto dos implantes osseointegráveis é resultado do desenvolvimento de diferentes tipos de estruturas em sua superfície. No entanto, ainda existe a necessidade de estudos para definir o tipo de superfície ideal. Esse trabalho discute métodos de avaliação da superfície de implantes que mostram o potencial de determinadas superfícies para induzir mineralização óssea in vitro, partir do uso de células mesenquimais progenitoras. Foram realizadas análises comparativas entre a topografia de implantes com e sem rugosidades nanométricas e o tipo de interação entre pré-osteoblastos semeados diretamente nesses implantes. Características distintas foram observadas em cada superfície.


Improvements in dental implants structure is the result of development of different types of geometrically intelligent surfaces, provided by the emergence of companies interested in innovation of these materials, however, there is still a need for studies to define the type of ideal surface. This work addresses an unprecedented discussion regarding implant surface evaluation methods, able to show the potential of certain areas to induce bone mineralization in vitro. From the use of mesenchymal progenitor cells, which have the capacity to respond to stimuli surface, comparative tests were performed between the topography implants with and without nano-roughness and the type of functional interaction between pre-osteoblasts seeded directly into these implants. Different characteristics of coating cells and mineralization niches on different surfaces were found.

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