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Progressive cognitive decline in Alzheimers disease could either be caused by a spreading molecular pathology or by an initially focal pathology that causes aberrant neuronal activity in a larger network. To distinguish between these possibilities, we generated a mouse model with expression of mutant human amyloid precursor protein (APP) in only hippocampal CA3 cells. We found that performance in a hippocampus-dependent memory task was impaired in young adult and aged mutant mice. In both age groups, we then recorded from the CA1 region, which receives inputs from APP-expressing CA3 cells. We observed that theta oscillation frequency in CA1 was reduced along with disrupted relative timing of principal cells. Highly localized pathology limited to the presynaptic CA3 cells is thus sufficient to cause aberrant firing patterns in postsynaptic neuronal networks, which indicates that disease progression is not only from spreading pathology but also mediated by progressively advancing physiological dysfunction.

Abstract The present work aimed to evaluate the use of modified atmosphere and peracetic acid on the quality and postharvest conservation of organic Formosa 'Tainung I' papaya. The experimental design was completely randomized (DIC) in a (2 x 3) x 5 split-plot scheme, with peracetic acid treatments (with and without 500ppm application) and packaging (Xtend® 815-pp64, Xtend® 815-pp65, and without packaging) in the plot, and days of storage (0, 10, 18, 26, 34 days) in the subplot, with five replicates of one fruit each. Peracetic acid treatment in combination with packaging maintained the postharvest quality attributes of organic Formosa 'Tainung I' papaya during storage. Peracetic acid-treated fruits stored in Packaging 1 (Xtend® 815 pp64) maintained their vitamin C, soluble solids, sugars, and beta-carotene contents. In Packaging 2 (Xtend® 815 pp65), fruits showed better external appearance, maintaining acceptable commercial quality for up to 26 days.

Background: Kidney transplantation is a life-saving treatment for end-stage kidney disease, but allograft rejection remains a critical challenge, requiring accurate and timely diagnosis. The study aims to evaluate the integration of Fourier Transform Infrared (FTIR) spectroscopy and machine learning algorithms as a minimally invasive method to detect kidney allograft rejection and differentiate between T Cell-Mediated Rejection (TCMR) and Antibody-Mediated Rejection (AMR). Additionally, the goal is to discriminate these rejection types aiming to develop a reliable decision-making support tool. Methods: This retrospective study included 41 kidney transplant recipients and analyzed 81 serum samples matched to corresponding allograft biopsies. FTIR spectroscopy was applied to pre-biopsy serum samples, and Naïve Bayes classification models were developed to distinguish rejection from non-rejection and classify rejection types. Data preprocessing involved, e.g., atmospheric compensation, second derivative, and feature selection using Fast Correlation-Based Filter for spectral regions 600–1900 cm−1 and 2800–3400 cm−1. Model performance was assessed via area under the receiver operating characteristic curve (AUC-ROC), sensitivity, specificity, and accuracy. Results: The Naïve Bayes model achieved an AUC-ROC of 0.945 in classifying rejection versus non-rejection and AUC-ROC of 0.989 in distinguishing TCMR from AMR. Feature selection significantly improved model performance, identifying key spectral wavenumbers associated with rejection mechanisms. This approach demonstrated high sensitivity and specificity for both classification tasks. Conclusions: The integration of FTIR spectroscopy with machine learning may provide a promising, minimally invasive method for early detection and precise classification of kidney allograft rejection. Further validation in larger, more diverse populations is needed to confirm these findings' reliability. [ABSTRACT FROM AUTHOR]

The two‐way propagation of a certain class of long‐crested water waves is governed approximately by systems of equations of the Boussinesq type. These equations have been put forward in various forms by many authors and their higher‐order generalizations arise when modeling the propagation of waves on large lakes, ocean, and in other contexts. Considered here is a class of such system which couple two higher‐order Korteweg–de‐Vries type equations. Our aim is to investigate the controllability properties of the linearized model posed on a periodic interval. By using the classical duality approach and some theorems on nonharmonic Fourier series, we prove that the system is exactly controllable in certain well‐chosen Sobolev spaces by means of suitable boundary controls. [ABSTRACT FROM AUTHOR]

No presente artigo, investiga-se historiográfica e etnograficamente, quatro jornais moçambicanos de grande circulação entre os anos de 1975 e 2007, no intuito de perceber como a imprensa do país tratou a questão da homossexualidade desde a independência. Conclui-se que a imprensa local, ao publicizar a homossexualidade de estrangeiros e não engajar em um discurso de ódio, reforçou a ideia da exogenia da homossexualidade em África e, diferente de outras nações africanas vizinhas, produziu um ambiente de tolerância para com a questão em Moçambique.

The Plasma Electrolytic Oxidation (PEO) process was investigated to enhance the adhesion of AA2024-O aluminum alloy with a polyetherimide (PEI) matrix composite, using oxy-fuel welding (OFW). A Central Composite Design (CCD) statistical model was used to optimize three independent parameters in PEO: immersion time (s), duty cycle (%), and electrolyte concentration (Na2B4O7·10H2O), aiming to achieve a maximum value of shear strength of the hybrid joint (in MPa). The hybrid joint without PEO treatment presented a resistance of 2.2 MPa while the best condition presented a resistance of 9.5 MPa, resulting in a value 4× higher than the untreated material, due to the characteristics of the coating, which presented a more hydrophilic surface, allowing better mechanical interlocking with the polymer matrix and resulting in mixed-mode failure (adhesive, cohesive, and light fiber). In addition to improving adhesion, the PEO treatment provided better corrosion resistance to the alloy, forming an inert aluminum oxide (Al2O3) coating, with an improvement of approximately 99.84% compared to the untreated alloy. The statistical design covers about 77.15% of the total variability of the PEO + welding process, with independent factors influencing around 48.4% of the variability. [ABSTRACT FROM AUTHOR]

The neural basis of tactile processing in humans has been extensively studied; however, the neurophysiological basis of human width discrimination remains relatively unexplored. In particular, the changes that occur in neural networks underlying active tactile width discrimination learning have yet to be described. Here, it is hypothesized that subjects learning to perform the active version of the width discrimination task would present changes in behavioral data and in the neurophysiological activity, specifically in networks of electrodes relevant for tactile and motor processing. The specific hypotheses tested here were that the performance and response latency of subjects would change between the first and the second blocks; the power of the different frequency bands would change between the first and the second blocks; electrode F4 would encode task performance and response latency through changes in the power of the delta, theta, alpha, beta, and low-gamma frequency bands; the relative power in the alpha and beta frequency bands in electrodes C3 and C4 (Interhemispheric Spectral Difference—ISD) would change because of learning between the first and the second blocks. To test this hypothesis, we recorded and analyzed electroencephalographic (EEG) activity while subjects performed a session where they were tested twice (i.e., two different blocks) in an active tactile width discrimination task using their right index finger. Subjects (n = 18) presented high performances (high discrimination accuracy) already in their first block, and therefore no significant improvements were found in the second block. Meanwhile, a reduction in response latency was observed between the two blocks. EEG recordings revealed an increase in power for the low-gamma frequency band (30–45 Hz) for electrodes F3 and C3 from the first to the second block. This change was correlated with neither performance nor latency. Analysis of the neural activity in electrode F4 revealed that the beta frequency band encoded the subjects' performance. Meanwhile, the delta frequency band in the same electrode revealed a complex pattern where blocks appeared clustered in two different patterns: an Upper Pattern (UP), where power and latency were highly correlated (Rho = 0.950), and a sparser and more uncorrelated Lower Pattern (LP). Blocks belonging to the UP or LP patterns did not differ in performance and were not specific to the first or the second block. However, blocks belonging to the LP presented an increase in response latency, increased variability in performance, and an increased ISD in alpha and beta frequency bands for the pair of electrodes C3–C4, suggesting that the LP may reflect a state related to increased cognitive load or task difficulty. These results suggest that changes in performance and latency in an active tactile width discrimination task are encoded in the delta, alpha, beta, and low-gamma frequency bands in a fronto-central network. The main contribution of this study is therefore related to the description of neural dynamics in frontal and central networks involved in the learning process of active tactile width discrimination. [ABSTRACT FROM AUTHOR]

RESUMO No presente artigo, fruto de pesquisa histórica e etnográfica, apresento alguns arquivos coloniais portugueses e estrangeiros no que concerne à vida (homo)sexual pretérita dos homens do sul de Moçambique. Ao trazer tais dados, que vão desde a literatura de viagem até os boletins oficiais da Província, argumento pela escassez de registros sobre o homoerotismo na história colonial de Moçambique até o século XX. Ao analisar os casamentos entre homens moçambicanos nas minas sul-africanas, e os processos - até agora inéditos - sobre a penalização das práticas homossexuais no período tardo-colonial em Moçambique, argumento que o silêncio sobre a sexualidade, atribuído aos bantus desta região, pode ser também efeito do pudor do colonizador português, ainda que tenha sido ele o instaurador, naquele território, de uma nova categoria: a “homossexualidade”.

Abstract The current paper is an ethnographic study of an international cooperation project between an international organisation for the fight against the HIV/AIDS epidemic and the organisation LAMBDA, the largest LGBT NGO in Mozambique. The objectives of this paper are, firstly, to demonstrate how due to the international flow of financial resources attached to certain concepts and agendas, these projects end up somehow institutionalising a homosexuality project in Mozambique, in addition to reviving potentially neo-colonial practices. It also seeks to demonstrate how external bureaucratic practices can clash with local cultural practices, in what has been called ‘NGOisation.’

This article aims to understand the process of “institutionalization” (Douglas, 2007) of homosexuality in Mozambique, based on the ethnographic case of the Café Púrpura radio program sponsored by LambdaMoz – the largest LGBT organization in the country – and broadcast nationally in 2018. Analyzing five of its episodes, we concluded that the Mozambican LGBT movement seeks not only to institutionalize homosexuality through discourses, symbols and values, but also from a specific political perspective, namely, a politics of “base” of non-violent confrontation against the wider society. In this sense, the data lead to reflection on an important native category in local homosexual semantics, “tolerance”.

A partir de pesquisa etnográfica e documental, o artigo apresenta uma genealogia do movimento LGBT moçambicano desde sua origem até os dias atuais. Nesse sentido, ele aborda as primeiras festas homossexuais; o primeiro jornal do movimento; a institucionalização do movimento na organização “LAMBDA”; e a relação desta última com o Estado moçambicano. Dois são os argumentos aqui apresentados: respondendo aos debates sobre os discursos de exogenia da homossexualidade em África, argumento que a história do movimento LGBT local é uma das razões pelas quais faz sentido para o senso comum, em Moçambique, atribuir a “homossexualidade” aos estrangeiros, aos brancos e à cidade. Em segundo lugar, o artigo busca se contrapor aos africanistas que enfatizam a homofobia no continente, demonstrando a particular ambiguidade que há na relação do Estado Moçambicano com o movimento LGBT local.

Resumo Maríyarapáxjis é um neologismo (proveniente da expressão portuguesa maria-rapaz) encontrado na língua materna de meus interlocutores moçambicanos (a língua changana) para dar conta, entre outros, de homens que a princípio demonstram certa afeminação, mas que nas últimas décadas passou também a nomear os homossexuais. Apesar de analisar outros vocábulos, escolho-o como título deste artigo porque, além de ser uma das palavras mais ouvidas no sul do país para nomear esses sujeitos, ela parece ser o epítome de uma série de processos históricos de institucionalização das homossexualidades masculinas nas classes populares do sul de Moçambique. O presente artigo, fruto de investigação etnográfica e linguística, busca analisar o léxico das línguas changana e portuguesa dentro do campo semântico da homossexualidade no sul de Moçambique e colocá-las em diálogo com as teorias feministas africanas.