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This study leverages deep learning to analyze sex differences in brain MRI data, aiming to further advance fairness in medical imaging. We employed 3D T1-weighted Magnetic Resonance images from four diverse datasets: Calgary-Campinas-359, OASIS-3, Alzheimer's Disease Neuroimaging Initiative, and Cambridge Center for Aging and Neuroscience, ensuring a balanced representation of sexes and a broad demographic scope. Our methodology focused on minimal preprocessing to preserve the integrity of brain structures, utilizing a Convolutional Neural Network model for sex classification. The model achieved an accuracy of 87% on the test set without employing total intracranial volume (TIV) adjustment techniques. We observed that while the model exhibited biases at extreme brain sizes, it performed with less bias when the TIV distributions overlapped more. Saliency maps were used to identify brain regions significant in sex differentiation, revealing that certain supratentorial and infratentorial regions were important for predictions. Furthermore, our interdisciplinary team, comprising machine learning specialists and a radiologist, ensured diverse perspectives in validating the results. The detailed investigation of sex differences in brain MRI in this study, highlighted by the sex differences map, offers valuable insights into sex-specific aspects of medical imaging and could aid in developing sex-based bias mitigation strategies, contributing to the future development of fair AI algorithms. Awareness of the brain's differences between sexes enables more equitable AI predictions, promoting fairness in healthcare outcomes. Our code and saliency maps are available at https://github.com/mahsadibaji/sex-differences-brain-dl.

Abstract We sought to investigate possible impaired hyperaemia during dynamic handgrip exercise (HGE) in young healthy individuals who had recovered from COVID‐19. We tested the vascular function in individuals recovered from COVID‐19 using a nitric oxide donor (i.e., sodium nitroprusside; SNP), which could revert a possible impaired endothelial function during HGE. Further, we tested whether individuals who recovered from COVID‐19 would present exaggerated brachial vascular resistance under an adrenergic agonist (i.e., phenylephrine; PHE) stimuli during HGE. Participants were distributed into two groups: healthy controls (Control; men: n = 6, 30 ± 3 years, 26 ± 1 kg/m2; and women: n = 5, 25 ± 1 years, 25 ± 1 kg/m2) and subjects recovered from COVID‐19 (post‐COVID; men: n = 6, 29 ± 3 years, 25 ± 1 kg/m2; and women: n = 10, 32 ± 4 years, 22 ± 1 kg/m2). Participants in the post‐COVID group tested positive (RT‐PCR) 12–14 weeks before the protocol. Heart rate (HR), brachial blood pressure (BP), brachial blood flow (BBF) and vascular conductance (BVC) at rest were not different between groups. The HGE increased HR (Control: Δ9 ± 0.4 bpm; and post‐COVID: Δ11 ± 0.4 bpm) and BP (Control: Δ6 ± 1 mmHg; and post‐COVID: Δ12 ± 0.6 mmHg) in both groups. Likewise, BBF (Control: Δ632 ± 38 ml/min; and post‐COVID: Δ620 ± 27 ml/min) and BVC (Control: Δ6.6 ± 0.4 ml/min/mmHg; and post‐COVID: Δ6.1 ± 0.3 ml/min/mmHg) increased during HGE. SNP did not change HGE‐induced hyperaemia but did decrease BP, which induced a reflex‐related increase in HR. PHE infusion also did not change the HGE‐induced hyperaemia but raised BP and reduced HR. In conclusion, exercise‐induced hyperaemia is preserved in healthy young subjects 12–14 weeks after recovery from COVID‐19 infection.

O presente trabalho trata-se de um recorte da dissertação de mestrado intitulada “A Cidadania na Formação Inicial dos Futuros Professores de Geografia: Um relato da UFT e Unifesspa”. As atenções se voltam para os futuros docentes de Geografia e sua formação inicial, trazendo a inquietude em saber: a) qual a concepção dos futuros professores de Geografia da Unifesspa, campus Marabá, e da UFT, campus Porto Nacional, sobre cidadania?; b) os respectivos cursos de licenciatura formam professores na perspectiva de formação cidadã?; c) Como se dá a formação inicial desses sujeitos perante as transformações no mundo contemporâneo?; d) de que maneira a Geografia contribui para a formação cidadã? Para a realização desta pesquisa, foram considerados alguns procedimentos com base nos objetivos propostos. As metodologias utilizadas foram: 1º) pesquisa e levantamento bibliográfico; 2º) análise documental do Projeto Pedagógico dos Cursos (PPC) de licenciatura em Geografia da Unifesspa e da UFT; 3º) elaboração e aplicação de questionários e por fim, 4º) discussões dos resultados obtidos após coleta de dados por meio dos questionários respondidos. A Geografia apresenta-se como um campo do conhecimento que auxilia o jovem educando no entendimento da sua realidade e na busca por mudanças, podendo atuar politicamente na construção de uma sociedade mais justa. Assim, faz-se necessário desde a formação inicial de professores de Geografia construir conhecimentos transformadores capazes de contribuir no exercício de uma Geografia escolar e na promoção de práticas cidadãs.

Abstract Simulation studies, such as finite element (FE) modeling, provide insight into knee joint mechanics without patient involvement. Generic FE models mimic the biomechanical behavior of the tissue, but overlook variations in geometry, loading, and material properties of a population. Conversely, subject-specific models include these factors, resulting in enhanced predictive precision, but are laborious and time intensive. The present study aimed to enhance subject-specific knee joint FE modeling by incorporating a semi-automated segmentation algorithm using a 3D Swin UNETR for an initial segmentation of the femur and tibia, followed by a statistical shape model (SSM) adjustment to improve surface roughness and continuity. For comparison, a manual FE model was developed through manual segmentation (i.e., the de-facto standard approach). Both FE models were subjected to gait loading and the predicted mechanical response was compared. The semi-automated segmentation achieved a Dice similarity coefficient (DSC) of over 98% for both the femur and tibia. Hausdorff distance (mm) between the semi-automated and manual segmentation was 1.4 mm. The mechanical results (max principal stress and strain, fluid pressure, fibril strain, and contact area) showed no significant differences between the manual and semi-automated FE models, indicating the effectiveness of the proposed semi-automated segmentation in creating accurate knee joint FE models. We have made our semi-automated models publicly accessible to support and facilitate biomechanical modeling and medical image segmentation efforts ( https://data.mendeley.com/datasets/k5hdc9cz7w/1 ).

Microalgae have a high growth rate, high CO2 absorption capacity, and high content of chlorophyll, proteins, vitamins, mineral salts, carbohydrates, antioxidant substances, and fatty acids. In recent years, Chlorella vulgaris has been widely used as a feedstock for producing third-generation biofuels, such as bioethanol. Thus, this work aims to develop a strategy to increase the production scale of the microalgae Chlorella vulgaris grown in distilled reused water, supplemented with a modified BG-11 medium, to use biomass in the production of bioethanol. The total cultivation of 72 L presented a concentration of 0.415 g·L−1·d−1, with 61.32 g of final biomass. To improve carbohydrate extraction, the biomass was pre-treated with sulfuric acid at different concentrations (1.5% and 3% v/v). The hydrolyzed solution was supplemented with YPD (yeast extract peptone dextrose) medium and inoculated with Saccharomyces cerevisae yeast, initiating fermentation. In each sample, the Brix degree, cell concentration, reducing sugar concentration, and alcohol content were analyzed. The sample pre-treated with sulfuric acid 1.5% v/v was the one that presented the best result, with alcohol content after distillation of 68 °GL (Gay-Lussac). It appears that the cultivation of the microalgae Chlorella vulgaris in scale-up, with reused water, has high potential in the production of third-generation biofuel.

Abstract Background Identifying early biomarkers of serious mental illness (SMI)—such as changes in brain structure and function—can aid in early diagnosis and treatment. Whole brain structural and functional connectomes were investigated in youth at risk for SMI. Methods Participants were classified as healthy controls (HC; n = 33), familial risk for serious mental illness (stage 0; n = 31), mild symptoms (stage 1a; n = 37), attenuated syndromes (stage 1b; n = 61), or discrete disorder (transition; n = 9) based on clinical assessments. Imaging data was collected from two sites. Graph-theory based analysis was performed on the connectivity matrix constructed from whole-brain white matter fibers derived from constrained spherical deconvolution of the diffusion tensor imaging (DTI) scans, and from the correlations between brain regions measured with resting state functional magnetic resonance imaging (fMRI) data. Results Linear mixed effects analysis and analysis of covariance revealed no significant differences between groups in global or nodal metrics after correction for multiple comparisons. A follow up machine learning analysis broadly supported the findings. Several non-overlapping frontal and temporal network differences were identified in the structural and functional connectomes before corrections. Conclusions Results suggest significant brain connectome changes in youth at transdiagnostic risk may not be evident before illness onset.

Magnetic resonance spectroscopy is a powerful, non-invasive, quantitative imaging technique that allows for the measurement of brain metabolites that has demonstrated utility in diagnosing and characterizing a broad range of neurological diseases. Its impact, however, has been limited due to small sample sizes and methodological variability in addition to intrinsic limitations of the method itself such as its sensitivity to motion. The lack of standardization from a data acquisition and data processing perspective makes it difficult to pool multiple studies and/or conduct multisite studies that are necessary for supporting clinically relevant findings. Based on the experience of the ENIGMA MRS work group and a review of the literature, this manuscript provides an overview of the current state of MRS data harmonization. Key factors that need to be taken into consideration when conducting both retrospective and prospective studies are described. These include (1) MRS acquisition issues such as pulse sequence, RF and B0 calibrations, echo time, and SNR; (2) data processing issues such as pre-processing steps, modeling, and quantitation; and (3) biological factors such as voxel location, age, sex, and pathology. Various approaches to MRS data harmonization are then described including meta-analysis, mega-analysis, linear modeling, ComBat and artificial intelligence approaches. The goal is to provide both novice and experienced readers with the necessary knowledge for conducting MRS data harmonization studies.

Accurate brain segmentation is critical for magnetic resonance imaging (MRI) analysis pipelines. Machine-learning-based brain MR image segmentation methods are among the state-of-the-art techniques for this task. Nevertheless, the segmentations produced by machine learning models often degrade in the presence of expected domain shifts between the test and train sets data distributions. These domain shifts are expected due to several factors, such as scanner hardware and software differences, technology updates, and differences in MRI acquisition parameters. Domain adaptation (DA) methods can make machine learning models more resilient to these domain shifts. This paper proposes a benchmark for investigating DA techniques for brain MR image segmentation using data collected across sites with scanners from different vendors (Philips, Siemens, and General Electric). Our work provides labeled data, publicly available source code for a set of baseline and DA models, and a benchmark for assessing different brain MR image segmentation techniques. We applied the proposed benchmark to evaluate two segmentation tasks: skull-stripping; and white-matter, gray-matter, and cerebrospinal fluid segmentation, but the benchmark can be extended to other brain structures. Our main findings during the development of this benchmark are that there is not a single DA technique that consistently outperforms others, and hyperparameter tuning and computational times for these methods still pose a challenge before broader adoption of these methods in the clinical practice.

Deep-learning-based brain magnetic resonance imaging (MRI) reconstruction methods have the potential to accelerate the MRI acquisition process. Nevertheless, the scientific community lacks appropriate benchmarks to assess the MRI reconstruction quality of high-resolution brain images, and evaluate how these proposed algorithms will behave in the presence of small, but expected data distribution shifts. The multi-coil MRI (MC-MRI) reconstruction challenge provides a benchmark that aims at addressing these issues, using a large dataset of high-resolution, three-dimensional, T1-weighted MRI scans. The challenge has two primary goals: (1) to compare different MRI reconstruction models on this dataset and (2) to assess the generalizability of these models to data acquired with a different number of receiver coils. In this paper, we describe the challenge experimental design and summarize the results of a set of baseline and state-of-the-art brain MRI reconstruction models. We provide relevant comparative information on the current MRI reconstruction state-of-the-art and highlight the challenges of obtaining generalizable models that are required prior to broader clinical adoption. The MC-MRI benchmark data, evaluation code, and current challenge leaderboard are publicly available. They provide an objective performance assessment for future developments in the field of brain MRI reconstruction.

O presente artigo é resultado de pesquisa de iniciação científica. A análise teórica baseou-se em uma revisão bibliográfica e a análise empírica baseou-se em um trabalho de campo com a aplicação de entrevistas e na coleta de dados estatísticos sobre emprego no banco de dados do Instituto Brasileiro de Geografia e estatística e no Atlas de Desenvolvimento Humano de 2000 e 2013. Tem como objetivo analisar, avaliar a dinâmica do emprego, a evolução e o desenvolvimento humano em Porto Nacional-TO. A investigação empírica foi desenvolvida a partir de dados estatísticos coletados no banco de dados do IBGE e PNUD e de entrevistas com líderes sindicais. Os resultados desta pesquisa estão expostos na forma de tabelas e de gráficos no texto.

The iamxt is an array-based max-tree toolbox implemented in Python using the NumPy library for array processing. It has state of the art methods for building and processing the max-tree, and a large set of visualization tools that allow to view the tree and the contents of its nodes. The array-based programming style and max-tree representation used in the toolbox make it simple to use. The intended audience of this toolbox includes mathematical morphology students and researchers that want to develop research in the field and image processing researchers that need a toolbox simple to use and easy to integrate in their applications. Keywords: Max-tree, Component tree, Mathematical morphology

O artigo levanta uma discussão teórica e empírica sobre as contribuições do processo de modernização na reorganização do espaço agrário e no fortalecimento político e econômico de um grupo de atores sociais vinculados ao agronegócio na Microrregião de Rondonópolis – MT, a partir da década de 1970, com a introdução do progresso técnico-científico no espaço agrário dentro do modelo de produção capitalista. Observa e estuda a influência da introdução do progresso técnico-científico na modernização da economia e do espaço agrário, bem como o papel que este progresso desempenhou no fortalecimento político e econômico do setor ligado ao agronegócio. O texto aborda as estratégias dos agentes do agronegócio no processo de produção tanto a montante quanto a jusante no setor agrícola. Observa as ações e estratégias de territorialização das empresas globais do agronegócio e sua influência na reorganização e produção do espaço regional e a subordinação dos agricultores à sua arena geopolítica comercial. Adotou-se o método qualitativo e a elaboração do artigo baseou-se em uma revisão bibliográfica e em uma pesquisa empírica. Após o levantamento bibliográfico, procedeu-se a compilação, organização das ideias e interpretação dos dados e informações teóricas e empíricas disponíveis na literatura adotada e nas pesquisas de campo.

BackgroundARFI elastrography has been used as a noninvasive method to assess the severity of liver fibrosis in viral hepatitis, although with few studies in schistosomiasis mansoni. We aimed to evaluate the performance of point shear wave elastography (pSWE) for predicting significant periportal fibrosis (PPF) in schistosomotic patients and to determine its best cutoff point.Methodology/principal findingsThis cross-sectional study included 358 adult schistosomotic patients subjected to US and pSWE on the right lobe. Two hundred two patients (62.0%) were women, with a median age of 54 (ranging 18-92) years. The pSWE measurements were compared to the US patterns of PPF, as gold standard, according to the Niamey classification. The performance of pSWE was calculated as the area under the ROC curve (AUC). Patients were further classified into two groups: 86 patients with mild PPF and 272 patients with significant PPF. The median pSWE of the significant fibrosis group was higher (1.40 m/s) than that of mild fibrosis group (1.14 m/s, p1.39 m/s, with specificity of 86.1% and positive predictive value of 92.0%.Conclusions/significancepSWE was able to differentiate significant from mild PPF, with better performance to predict significant PPF.

INTRODUCTION: Thyroid gland exposures to radiation induce nuclear chromosomal alteration. Objective: To evaluate the DNA content of thyroid gland submitted to radiation. MATERIALS AND METHODS: We radiated 75 rats while 25 were not radiated to be used as control group. Exposure was conducted by the use of Cobalt-60 radioactive source in the right anterior cervical region in a field of 3-30cm, comprising the second and the sixth tracheal rings with 600-centigray (cGY) doses. The DNA content (ploidy) was obtained with Feulgen-thionin stain and was quantified with CAS 200 quantitative measurement equipment. RESULTS: Diploid pattern was obtained in 88 cases (95.7%), independently of time of exposure: on the other hand, aneuploidy was observed in four cases (4.3%) only in the group sacrificed to the 33 days. Eight cases were excluded due to technical reasons. CONCLUSION: The early aneuploid pattern found in our study certainly corroborated that radiation affects thyroid gland with important consequences in terms of disorders.INTRODUÇÃO: A exposição da tireóide à irradiação está associada à alteração do componente cromossômico nessa glândula. OBJETIVO: Avaliar o conteúdo de DNA (ploidia) em glândula tireóide submetida à radiação. MATERIAL E MÉTODOS: Foram irradiadas tireóides de 75 ratos; 25 foram usados como grupo controle e não sofreram irradiação. A exposição à irradiação foi realizada com o uso de Cobalt-60 na região cervical anterior direita com espaço de 3-30cm, com anel traqueal de 2º e 6º e dose de 600 centigrays (cGY). O conteúdo de DNA (ploidia) foi obtido com o método de Feulgen-Thionin e quantificado com o aparelho CAS 200 de citometria estática. RESULTADO: Dos 92 casos, 88 (95,7%) foram diplóides, independente do tempo de exposição; aneuploidia foi observada em quatro casos (4,3%), somente no grupo sacrificado aos 33 dias. Oito casos foram excluídos por problemas técnicos. CONCLUSÃO: A irradiação afeta muito precocemente o conteúdo de DNA nuclear levando a aneuploidia.

Este artigo tem como finalidade abordar o processo de urbanização e a reprodução da força de trabalho na região e levantar uma discussão teórica sobre o papel do Estado na formação e na expansão da fronteira agropecuária, desde início dos anos 40 até os dias atuais. Também pretende identificar os fatores que deram origem às cidades na região e proporcionaram seu crescimento na malha urbana Mato Grosso. Analisar o papel do Estado que, através de suas políticas públicas de investimento direcionadas para a ocupação do território pouco povoado, procura organizar o território, a organização do modo de produção e estrutura e organiza a fronteira agrícola. Abordar a importância do capital agropecuário como agente que contribui para a ocupação demográfica da região através da introdução de novas técnicas, agroindústrias, infraestrutura urbana e não urbana motivando o fenômeno imigratório.

O presente artigo teve seus fundamentos embasados em resultados de longo período de observação e percepção comportamental de vários servidores do Instituto Médico Legal de São Paulo, ao longo do período de convivência profissional com esses servidores e o evento morte, período de experiência de cerca de 35 anos para cada autor, diuturnamente em contato com o ambiente das mais variadas unidades de IMLs como médicos legistas. Para tanto, propôs-se como reflexão em torno desse tema central os seguintes questionamentos: qual a proximidade de um “Trabalhador da morte” com a morte?; o que realmente atormenta o estado psicológico do trabalhador envolvido com a morte?; o que gera o dilema e instala o trauma? Concluiu-se que é preciso trazer esse servidor ao enfrentamento da realidade em que vive, sem fugas ou máscaras, demonstrando a sua relevante contribuição à sociedade.

0 objetivo principal do trabalho foi o de verificar o valor do emprego da endoscopia como método de avaliação pós-cirúrgica, em cães submetidos aesofagectomia cervical parcial, associada a miotomias relaxadoras. Utilizaram-se, para tal, 25 animais que foram submetidos a exame endoscópico entre o 2º e o 44º dia após sofrerem esofagectomia cervical parcial de 4,0 cm de comprimento, anastomose térmico-terminal em plano único de sutura e miotomias transversais totais distantes 2,0 cm cranial e caudalmente ao bordo da sutura. Diante dos resultados obtidos, concluiu-se que a endoscopia permitiu avaliar de maneira clara, segura e pormenorizada, os fenômenos relativos à cicatrização cirúrgica, bem como acompanhar as complicações dos procedimentos cirúrgicos empregados. Mostrou, ainda, ser o exame endoscópico, método rápido, eficaz e seguro, sendo indicado seu emprego na avaliação pós-cirúrgica de esofagectomias cervicais parciais e miotomias relaxadoras transversais em cães.

OBJETIVO: Os carcinomas epidermóides do trato aerodigestivo superior são tumores de comportamento biológico heterogêneo. O objetivo deste trabalho é verificar se a expressão imuno-histoquímica dos marcadores Ki67, PCNA e P53 apresenta correlações com parâmetros prognósticos clínico-patológicos. MÉTODOS: Determinação da expressão imuno-histoquímica dos antígenos Ki67, PCNA e P53 em espécimes tumorais fixados e embebidos em parafina de 53 pacientes com carcinoma epidermóide em diferentes sítios primários do trato aerodigestivo superior. RESULTADOS: Os marcadores tiveram altos índices de expressão imuno-histoquímica, sendo 46,5% para o Ki67, 66,5% para o PCNA e 36,5% para o P53. Não houve correlação da expressão do Ki67 e do PCNA com o estadiamento TNM (AJCC), nem com o grau de malignidade. A expressão do Ki67 apresentou correlação positiva com a expressão do PCNA (p = 0,037). O mesmo aconteceu para o PCNA e o número de mitoses por campo (p = 0,001). CONCLUSÕES: De acordo com estes resultados, concluiu-se que a determinação da imunorreatividade dos marcadores Ki67 e PCNA é um método objetivo e quantificável para avaliar proliferação celular que pode subsidiar as informações prognósticas.

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