Non-Invasive Fish Biometrics for Enhancing Precision and Understanding of Aquaculture Farming through Statistical Morphology Analysis and Machine Learning.

Aquaculture requires precise non-invasive methods for biomass estimation. This research validates a novel computer vision methodology that uses a signature function-based feature extraction algorithm combining statistical morphological analysis of the size and shape of fish and machine learning to improve the accuracy of biomass estimation in fishponds and is specifically applied to tilapia (Oreochromis niloticus). These features that are automatically extracted from images are put to the test against previously manually extracted features by comparing the results when applied to three common machine learning methods under two different lighting conditions. The dataset for this analysis encompasses 129 tilapia samples. The results give promising outcomes since the multilayer perceptron model shows robust performance, consistently demonstrating superior accuracy across different features and lighting conditions. The interpretable nature of the model, rooted in the statistical features of the signature function, could provide insights into the morphological and allometric changes at different developmental stages. A comparative analysis against existing literature underscores the competitiveness of the proposed methodology, pointing to advancements in precision, interpretability, and species versatility. This research contributes significantly to the field, accelerating the quest for non-invasive fish biometrics that can be generalized across various aquaculture species in different stages of development. In combination with detection, tracking, and posture recognition, deep learning methodologies such as the one provided in the latest studies could generate a powerful method for real-time fish morphology development, biomass estimation, and welfare monitoring, which are crucial for the effective management of fish farms.

Orientaciones para el manejo ambulatorio de adultos que viven con VIH en Chile / Guidelines for the primary care of adult people living with HIV in Chile

El enfrentamiento de las personas que viven con VIH es amplio y requiere dedicación en múltiples dimensiones, más allá de la terapia antirretroviral. Estas recomendaciones abordan el manejo desde el diagnóstico, primera visita, seguimiento, manejo de comorbilidades infecciosas y no infecciosas, tamizaje de neoplasias, profilaxis antimicrobiana y vacunas, entre otras.

Management of people living with HIV is broad and multiple dimensions must be considered, beyond antiretroviral therapy. These recommendations include management from diagnosis, first visit, patient follow-up, infectious and non-infectious comorbidities, malignancies screening, antimicrobial and immunizations prophylaxis, among others.

Numerical Study of a Solar Cell to Achieve the Highest InGaN Power Conversion Efficiency for the Whole In-Content Range.

A solar cell structure with a graded bandgap absorber layer based on InGaN has been proposed to overcome early predicted efficiency. Technological issues such as carrier concentration in the p- and n-type are based on the data available in the literature. The influence of carrier concentration-dependent mobility on the absorber layer has been studied, obtaining considerable improvements in efficiency and photocurrent density. Efficiency over the tandem solar cell theoretical limit has been reached. A current density of 52.95 mA/cm2, with an efficiency of over 85%, is determined for a PiN structure with an InGaN step-graded bandgap absorption layer and 65.44% of power conversion efficiency for the same structure considering piezoelectric polarization of fully-strained layers and interfaces with electron and hole surface recombination velocities of 10-3 cm/s.

First report and genetic characterization of Seneca Valley virus (SVV) in Chile.

Seneca Valley virus (SVV) is a non-enveloped RNA virus and the only member of the Senecavirus A (SVA) species, in the Senecavirus genus, Picornaviridae family. SVV infection causes vesicular lesions in the oral cavity, snout and hooves of pigs. This infection is clinically indistinguishable from trade-restrictions-related diseases such as foot-and-mouth disease. Other clinical manifestations include diarrhoea, anorexia, lethargy, neurological signs and mortality in piglets during their first week of age. Before this study, Chile was considered free of vesicular diseases of swine, including SVV. In April 2022, a suspected case of vesicular disease in a swine farm was reported in Chile. The SVV was confirmed and other vesicular diseases were ruled out. An epidemiological investigation and phylogenetic analyses were performed to identify the origin and extent of the outbreak. Three hundred ninety-five samples from 44 swine farms were collected, including faeces (208), oral fluid (28), processing fluid (14), fresh semen (61), environmental samples (80) and tissue from lesions (4) for real-time RT-PCR detection. Until June 2022, the SVV has been detected in 16 out of 44 farms, all epidemiologically related to the index farm. The closest phylogenetic relationship of the Chilean SVV strain is with viruses collected from swine in California in 2017. The direct cause of the SVV introduction has not yet been identified; however, the phylogenetic analyses suggest the USA as the most likely source. Since the virus remains active in the environment, transmission by fomites such as contaminated feed cannot be discarded. Further studies are needed to determine the risk of the introduction of novel SVV and other transboundary swine pathogens to Chile.

Conocimiento y conductas asociadas al uso comunitario de antimicrobianos en adultos en Santiago de Chile / Knowledge and behaviors regarding community antimicrobial use in a group of adults in Santiago de Chile

INTRODUCCIÓN: El uso de antimicrobianos se asocia a efectos laterales como alergias, reacciones adversas específicas y emergencia de resistencia antimicrobiana. Resulta fundamental una comunicación de riesgo efectiva a la población general sobre su utilidad y potenciales problemas. Experiencias internacionales revelan un bajo grado de conocimiento en la comunidad en países sin políticas educativas dirigidas, lo que mejora tras su implementación; a nivel regional y nacional existen escasas publicaciones al respecto. OBJETIVO: Describir el grado de conocimiento y conductas sobre el uso de antimicrobianos en adultos de Santiago de Chile. MÉTODOS: Estudio transversal realizado mediante una encuesta a adultos en Santiago de Chile, evaluando cuatro aspectos sobre antimicrobianos: conocimiento, uso reciente, conductas sobre su uso y nociones sobre resistencia antimicrobiana. RESULTADOS: Se encuestaron 300 personas entre 18 y 81 años (tres fueron descartadas posteriormente), siendo 75% de ellas menores de 45 años. Un 65% de los encuestados cree que los antibióticos antimicrobianos son activos frente a virus, 51% cree que sirven para tratar el resfrío común y 32% los ha utilizado sin receta. Un 51% ha escuchado el término resistencia antimicrobiana y 33% conoce su definición correcta. CONCLUSIÓN: El conocimiento sobre la utilidad y problemas de los antimicrobianos en población chilena es deficiente, lo que podría favorecer su uso inapropiado.

BACKGROUND: Antimicrobials use is associated with diverse secondary effects, as allergies, specific adverse drug reactions and emergence of antimicrobial resistance. Effective risk communication to the general public about their uses and potential issues is critical. International experience reveals deficient knowledge in countries without educational policies regarding this issue, but their implementation can reverse such deficit. There are scarce publications at regional and national level about these topics. AIM: To describe the knowledge and behaviors regarding antimicrobial use in adults in Santiago de Chile. METHODS: We conducted a cross-sectional study through a survey in 300 people in Santiago de Chile, evaluating 4 areas about antimicrobials: knowledge, use, behaviors, and antimicrobial resistance knowledge. RESULTS: 297 people were surveyed with ages between 18 and 81 years old. Seventy-five percent of them were younger than 45 years old. 65% of the surveyed thinks antimicrobials works against viruses, 51% believes they work against the common cold and 32% of the population has used them without a prescription. Fifty-one percent of the sample has heard about antimicrobial resistance and 33% knows its correct definition. CONCLUSIONS: The Chilean population has an important deficit in antimicrobial knowledge and use.

Effectiveness of manual therapy in patients with thumb carpometacarpal osteoarthritis: a systematic review and meta-analysis.

BACKGROUND: The effectiveness of Manual Therapy (MT) in thumb carpometacarpal osteoarthritis (OA) is unclear. OBJECTIVE: This study aimed to determine the effectiveness of MT for functional outcomes in patients with thumb carpometacarpal OA. DESIGN: Systematic review and meta-analysis of randomized clinical trials. METHODS: An electronic search was performed in the Medline, Central, Embase, PEDro, Lilacs, Cinahl, SPORTDiscus, and Web of Science databases. The eligibility criteria for selecting studies included randomized clinical trials that compared MT versus other interventions in functional outcomes, such as thumb and/or hand function questionnaires, pinch and/or grip strength, thumb and/or hand range of motion, and pain intensity or pressure pain threshold in patients with thumb carpometacarpal OA. RESULTS: Five clinical trials met the eligibility criteria; for the quantitative synthesis, four studies were included. The mean difference (MD) for grip strength was 0.87kg (95% CI = 0.29-1.44, p = .003), for pinch strength was 0.10kg (95% CI = -0.01-0.20, p = .06), and for the pressure pain threshold was 0.64kg/cm2 (95% CI = 0.07-1.20, p = .03). All differences were in favor of the MT group. CONCLUSIONS: In the short-term, there was moderate to high evidence, with statistically significant differences in the functional outcomes, in favor of MT versus sham interventions in patients with thumb carpometacarpal OA. However, these differences are not clinically important.

Optical Method for Estimating the Chlorophyll Contents in Plant Leaves.

This work introduces a new vision-based approach for estimating chlorophyll contents in a plant leaf using reflectance and transmittance as base parameters. Images of the top and underside of the leaf are captured. To estimate the base parameters (reflectance/transmittance), a novel optical arrangement is proposed. The chlorophyll content is then estimated by using linear regression where the inputs are the reflectance and transmittance of the leaf. Performance of the proposed method for chlorophyll content estimation was compared with a spectrophotometer and a Soil Plant Analysis Development (SPAD) meter. Chlorophyll content estimation was realized for Lactuca sativa L., Azadirachta indica, Canavalia ensiforme, and Lycopersicon esculentum. Experimental results showed that-in terms of accuracy and processing speed-the proposed algorithm outperformed many of the previous vision-based approach methods that have used SPAD as a reference device. On the other hand, the accuracy reached is 91% for crops such as Azadirachta indica, where the chlorophyll value was obtained using the spectrophotometer. Additionally, it was possible to achieve an estimation of the chlorophyll content in the leaf every 200 ms with a low-cost camera and a simple optical arrangement. This non-destructive method increased accuracy in the chlorophyll content estimation by using an optical arrangement that yielded both the reflectance and transmittance information, while the required hardware is cheap.

Epidemiological investigations of the introduction of porcine reproductive and respiratory syndrome virus in Chile, 2013-2015.

Porcine reproductive and respiratory syndrome (PRRS) is endemic in most pork producing countries. In Chile, eradication of PRRS virus (PRRSV) was successfully achieved in 2009 as a result of the combined efforts of producers and the animal health authorities. In October 2013, after several years without detecting PRRSV under surveillance activities, suspected cases were confirmed on a commercial swine farm. Here, we describe the PRRS epidemic in Chile between October 2013 and April 2015, and we studied the origins and spread of PRRSV throughout the country using official surveillance data and Bayesian phylogenetic analysis. Our results indicate that the outbreaks were caused by a PRRSV closely related to viruses present in swine farms in North America, and different from the strain that circulated in the country before 2009. Using divergence time estimation analysis, we found that the 2013-2015 PRRSV may have been circulating in Chile for at least one month before the first detection. A single strain of PRRSV spread into a limited number of commercial and backyard swine farms. New infections in commercial systems have not been reported since October 2014, and eradication is underway by clearing the disease from the few commercial and backyard farms that remain positive. This is one of the few documented experiences of PRRSV introduction into a disease-free country.

Platelet tau pattern correlates with cognitive status in Alzheimer's disease.

Platelets are major reservoirs of circulating amyloid-ß and amyloid-ß protein precursor (AßPP) and have been postulated as a reliable source for biological markers of Alzheimer's disease (AD). We have recently demonstrated that tau is also present in platelets, and that there are differences in the electrophoretic patterns of platelet tau forms in AD subjects with respect to controls. Here, we demonstrate that modifications in platelet tau forms occur independently of age in a broad population of 104 neurologically healthy individuals. More interesting, a strong correlation of platelet markers with the degree of cognitive impairment was evidenced in a group of 47 AD patients in comparison with 19 cognitive healthy subjects. In our series, platelet tau forms ratio had a sensitivity of 75.7% and specificity of 73.7%, respectively. We also found that platelet tau displays a significantly higher correlation with the presence of AD than the analyses of platelet AßPP.

Carbon monoxide concentration forecasting in Santiago, Chile.

In the city of Santiago, Chile, air quality is defined in terms of particulate matter with an aerodynamic diameter < or = 10 microm (PM10) concentrations. An air quality forecasting model based on past concentrations of PM10 and meteorological conditions currently is used by the metropolitan agency for the environment, which allows restrictions to emissions to be imposed in advance. This model, however, fails to forecast between 40 and 50% of the days considered to be harmful for the inhabitants every year. Given that a high correlation between particulate matter and carbon monoxide (CO) concentrations is observed at monitoring stations in the city, a model for CO concentration forecasting would be a useful tool to complement information about expected air quality in the city. Here, the results of a neural network-based model aimed to forecast maximum values of the 8-hr moving average of CO concentrations for the next day are presented. Forecasts from the neural network model are compared with those produced with linear regressions. The neural network model seems to leave more room to adjust free parameters with 1-yr data to predict the following year's values. We have worked with 3 yr of data measured at the monitoring station located in the zone with the worst air quality in the city of Santiago, Chile.