The SPECTRAL Perfusion Arm Clamping dAtaset (SPECTRALPACA) for video-rate functional imaging of the skin.

Spectral imaging has the potential to become a key technique in interventional medicine as it unveils much richer optical information compared to conventional RBG (red, green, and blue)-based imaging. Thus allowing for high-resolution functional tissue analysis in real time. Its higher information density particularly shows promise for the development of powerful perfusion monitoring methods for clinical use. However, even though in vivo validation of such methods is crucial for their clinical translation, the biomedical field suffers from a lack of publicly available datasets for this purpose. Closing this gap, we generated the SPECTRAL Perfusion Arm Clamping dAtaset (SPECTRALPACA). It comprises ten spectral videos (∼20 Hz, approx. 20,000 frames each) systematically recorded of the hands of ten healthy human participants in different functional states. We paired each spectral video with concisely tracked regions of interest, and corresponding diffuse reflectance measurements recorded with a spectrometer. Providing the first openly accessible in human spectral video dataset for perfusion monitoring, our work facilitates the development and validation of new functional imaging methods.

Test-time augmentation with synthetic data addresses distribution shifts in spectral imaging.

PURPOSE: Surgical scene segmentation is crucial for providing context-aware surgical assistance. Recent studies highlight the significant advantages of hyperspectral imaging (HSI) over traditional RGB data in enhancing segmentation performance. Nevertheless, the current hyperspectral imaging (HSI) datasets remain limited and do not capture the full range of tissue variations encountered clinically. METHODS: Based on a total of 615 hyperspectral images from a total of 16 pigs, featuring porcine organs in different perfusion states, we carry out an exploration of distribution shifts in spectral imaging caused by perfusion alterations. We further introduce a novel strategy to mitigate such distribution shifts, utilizing synthetic data for test-time augmentation. RESULTS: The effect of perfusion changes on state-of-the-art (SOA) segmentation networks depended on the organ and the specific perfusion alteration induced. In the case of the kidney, we observed a performance decline of up to 93% when applying a state-of-the-art (SOA) network under ischemic conditions. Our method improved on the state-of-the-art (SOA) by up to 4.6 times. CONCLUSION: Given its potential wide-ranging relevance to diverse pathologies, our approach may serve as a pivotal tool to enhance neural network generalization within the realm of spectral imaging.

Micronuclei, Pesticides, and Element Mixtures in Mining Contexts: The Hormetic Effect of Selenium.

The contexts where there are mining and agriculture activities are potential sources of risk to human health due to contamination by chemical mixtures. These contexts are frequent in several Colombian regions. This study explored the potential association between the frequency of micronuclei and pesticides and elements in regions with ferronickel (Montelibano, Córdoba) and gold (Nechí, Antioquia) mining, and a closed native mercury mine (Aranzazu, Caldas), with an emphasis in the potential effect of selenium as a potential chelator. A cross-sectional study was carried out with 247 individuals. Sociodemographic, occupational, and toxicological variables were ascertained. Blood and urine samples were taken for pesticide analysis (5 organophosphates, 4 organochlorines, and 3 carbamates), 68 elements were quantified in hair, and micronuclei were quantified in lymphocytes. The mixtures of elements were grouped through principal component analysis. Prevalence ratios were estimated with robust variance Poisson regressions to explore associations. Interactions of selenium with toxic elements were explored. The highest concentrations of elements were in the active mines. The potentially most toxic chemical mixture was observed in the ferronickel mine. Pesticides were detected in a low proportion of participants (<2.5%), except paraoxon-methyl in blood (27.55%) in Montelibano and paraoxon-ethyl in blood (18.81%) in Aranzazu. The frequency of micronuclei was similar in the three mining contexts, with means between 4 to 7 (p = 0.1298). There was great heterogeneity in the exposure to pesticides and elements. The "hormetic effect" of selenium was described, in which, at low doses, it acts as a chelator in Montelibano and Aranzazu, and at high doses, it can enhance the toxic effects of other elements, maybe as in Nechí. Selenium can serve as a protective agent, but it requires adaptation to the available concentrations in each region to avoid its toxic effects.

HeiPorSPECTRAL - the Heidelberg Porcine HyperSPECTRAL Imaging Dataset of 20 Physiological Organs.

Hyperspectral Imaging (HSI) is a relatively new medical imaging modality that exploits an area of diagnostic potential formerly untouched. Although exploratory translational and clinical studies exist, no surgical HSI datasets are openly accessible to the general scientific community. To address this bottleneck, this publication releases HeiPorSPECTRAL ( https://www.heiporspectral.org ; https://doi.org/10.5281/zenodo.7737674 ), the first annotated high-quality standardized surgical HSI dataset. It comprises 5,758 spectral images acquired with the TIVITA® Tissue and annotated with 20 physiological porcine organs from 8 pigs per organ distributed over a total number of 11 pigs. Each HSI image features a resolution of 480 × 640 pixels acquired over the 500-1000 nm wavelength range. The acquisition protocol has been designed such that the variability of organ spectra as a function of several parameters including the camera angle and the individual can be assessed. A comprehensive technical validation confirmed both the quality of the raw data and the annotations. We envision potential reuse within this dataset, but also its reuse as baseline data for future research questions outside this dataset. Measurement(s) Spectral Reflectance Technology Type(s) Hyperspectral Imaging Sample Characteristic - Organism Sus scrofa.

Mortalidad perioperatoria en Tolima, perspectivas del cuarto indicador de The Lancet Commission on Global Surgery: Un análisis preliminar de la cohorte prospectiva del estudio Colombian Surgical Outcomes Study (ColSOS) / Perioperative mortality in Tolima and perspectives of the fourth indicator of The Lancet Commission on Global Surgery: A preliminary analysis of the prospective cohort of the Colombian Surgical Outcomes Study (ColSOS)

Introducción. La mortalidad perioperatoria en el mundo representa 4,2 millones de muertes anuales. El cuarto indicador de The Lancet Commission on Global Surgery permite estandarizar la mortalidad perioperatoria. En Colombia, existen aproximaciones por datos secundarios, limitando el análisis y las intervenciones aplicables a nuestra población. El objetivo de este estudio fue describir la mortalidad perioperatoria a través de datos primarios que permitan sustentar políticas públicas. Métodos. Se hizo el análisis preliminar de un estudio observacional, de cohorte prospectiva, multicéntrico en 6 instituciones del departamento de Tolima. Se incluyeron los pacientes llevados a procedimientos quirúrgicos por una semana, con posterior seguimiento hasta el egreso, fallecimiento o 30 días de hospitalización. La mortalidad perioperatoria fue el desenlace primario. Resultados. Fueron incluidos 378 pacientes, con mediana de 49 años (RIC 32-66), buen estado funcional (ASA I-II 80 %) y baja complejidad quirúrgica (42 %). Las cirugías más comunes fueron por Ortopedia (25,4 %) y Cirugía plástica (23,3 %). El 29,7 % presentaron complicaciones postoperatorias, las más comunes fueron síndrome de dificultad respiratoria agudo e íleo postoperatorio. La mortalidad perioperatoria fue de 1,3 %. Discusión. La mortalidad perioperatoria discrepó de la reportada en otros estudios nacionales, aun cuando los pacientes tenían un bajo perfil de riesgo y baja complejidad de los procedimientos. Sin embargo, coincide con la reportada internacionalmente y nos acerca a la realidad del país. Conclusión. La determinación del cuarto indicador es de vital importancia para mejorar la atención quirúrgica en Colombia. Este es el primer acercamiento con datos primarios que nos permite tener información aplicable a nuestra población

Introduction. Perioperative mortality accounts for 4.2 million deaths annually. The fourth indicator of The Lancet Commission on Global Surgery allows standardizing perioperative mortality. In Colombia, there are approximations based on secondary data, limiting the analysis and interventions applicable to our population. The objective of this study is to describe perioperative mortality through primary data that allow supporting public policies. Methods. A preliminary analysis of an observational, prospective cohort, multicenter study was carried out at six institutions in the District of Tolima. Patients undergoing surgical procedures were included for one week, for subsequent follow-up until discharge, death, or 30 days of hospitalization. Perioperative mortality was the primary outcome and was presented as a proportion. Results. A total of 378 patients were included, with a median age of 49 years (RIC 32-66), low-risk profile (ASA I-II 80%), and low surgical complexity (42%). The most common surgeries were Orthopedic (25.4%) and Plastic Surgery (23.3%). Postoperative complications occurred in 29.7%, the most common were ARDS and postoperative ileus. Perioperative mortality was 1.3%. Discussion. Perioperative mortality differed from that reported in national studies, even when the patients had a low-risk profile and low complexity of the procedures. However, it coincides with that reported internationally and brings us closer to the reality of the country. Conclusion. The determination of the fourth indicator is of vital importance to improving surgical care in Colombia. This is the first approach with primary data that allows us to have applicable information for our population

Spectral imaging enables contrast agent-free real-time ischemia monitoring in laparoscopic surgery.

Laparoscopic surgery has evolved as a key technique for cancer diagnosis and therapy. While characterization of the tissue perfusion is crucial in various procedures, such as partial nephrectomy, doing so by means of visual inspection remains highly challenging. We developed a laparoscopic real-time multispectral imaging system featuring a compact and lightweight multispectral camera and the possibility to complement the conventional surgical view of the patient with functional information at a video rate of 25 Hz. To enable contrast agent-free ischemia monitoring during laparoscopic partial nephrectomy, we phrase the problem of ischemia detection as an out-of-distribution detection problem that does not rely on data from any other patient and uses an ensemble of invertible neural networks at its core. An in-human trial demonstrates the feasibility of our approach and highlights the potential of spectral imaging combined with advanced deep learning-based analysis tools for fast, efficient, reliable, and safe functional laparoscopic imaging.

ICG-augmented hyperspectral imaging for visualization of intestinal perfusion compared to conventional ICG fluorescence imaging: an experimental study.

BACKGROUND: Small bowel malperfusion (SBM) can cause high morbidity and severe surgical consequences. However, there is no standardized objective measuring tool for the quantification of SBM. Indocyanine green (ICG) imaging can be used for visualization, but lacks standardization and objectivity. Hyperspectral imaging (HSI) as a newly emerging technology in medicine might present advantages over conventional ICG fluorescence or in combination with it. METHODS: HSI baseline data from physiological small bowel, avascular small bowel and small bowel after intravenous application of ICG was recorded in a total number of 54 in-vivo pig models. Visualizations of avascular small bowel after mesotomy were compared between HSI only (1), ICG-augmented HSI (IA-HSI) (2), clinical evaluation through the eyes of the surgeon (3) and conventional ICG imaging (4). The primary research focus was the localization of resection borders as suggested by each of the four methods. Distances between these borders were measured and histological samples were obtained from the regions in between in order to quantify necrotic changes 6 h after mesotomy for every region. RESULTS: StO2 images (1) were capable of visualizing areas of physiological perfusion and areas of clearly impaired perfusion. However, exact borders where physiological perfusion started to decrease could not be clearly identified. Instead, IA-HSI (2) suggested a sharp-resection line where StO2 values started to decrease. Clinical evaluation (3) suggested a resection line 23 mm (±7 mm) and conventional ICG imaging (4) even suggested a resection line 53 mm (±13 mm) closer towards the malperfused region. Histopathological evaluation of the region that was sufficiently perfused only according to conventional ICG (R3) already revealed a significant increase in pre-necrotic changes in 27% (±9%) of surface area. Therefore, conventional ICG seems less sensitive than IA-HSI with regards to detection of insufficient tissue perfusion. CONCLUSIONS: In this experimental animal study, IA-HSI (2) was superior for the visualization of segmental SBM compared to conventional HSI imaging (1), clinical evaluation (3) or conventional ICG imaging (4) regarding histopathological safety. ICG application caused visual artifacts in the StO2 values of the HSI camera as values significantly increase. This is caused by optical properties of systemic ICG and does not resemble a true increase in oxygenation levels. However, this empirical finding can be used to visualize segmental SBM utilizing ICG as contrast agent in an approach for IA-HSI. Clinical applicability and relevance will have to be explored in clinical trials. LEVEL OF EVIDENCE: Not applicable. Translational animal science. Original article.

Perioperative mortality in Colombia: perspectives of the fourth indicator in The Lancet Commission on Global Surgery - Colombian Surgical Outcomes Study (ColSOS) - a protocol for a multicentre prospective cohort study.

INTRODUCTION: Death following surgical procedures is a global health problem, accounting for 4.2 million deaths annually within the first 30 postoperative days. The fourth indicator of The Lancet Commission on Global Surgery is essential as it seeks to standardise postoperative mortality. Consequently, it helps identify the strengths and weaknesses of each country's healthcare system. Accurate information on this indicator is not available in Colombia, limiting the possibility of interventions applied to our population. We aim to describe the in-hospital perioperative mortality of the surgical procedures performed in Colombia. The data obtained will help formulate public policies, improving the quality of the surgical departments. METHODS AND ANALYSIS: An observational, analytical, multicentre prospective cohort study will be conducted throughout Colombia. Patients over 18 years of age who have undergone a surgical procedure, excluding radiological/endoscopic procedures, will be included. A sample size of 1353 patients has been projected to achieve significance in our primary objective; however, convenience sampling will be used, as we aim to include all possible patients. Data collection will be carried out prospectively for 1 week. Follow-up will continue until hospital discharge, death or a maximum of 30 inpatient days. The primary outcome is perioperative mortality. A descriptive analysis of the data will be performed, along with a case mix analysis of mortality by procedure-related, patient-related and hospital-related conditions ETHICS AND DISSEMINATION: The Fundación Cardioinfantil-Instituto de Cardiología Ethics Committee approved this study (No. 41-2021). The results are planned to be disseminated in three scenarios: the submission of an article for publication in a high-impact scientific journal and presentations at the Colombian Surgical Forum and the Congress of the American College of Surgeons. TRIAL REGISTRATION NUMBER: NCT05147623.

C-arm positioning for standard projections during spinal implant placement.

Fluoroscopy-guided trauma and orthopedic surgeries involve the repeated acquisition of correct anatomy-specific standard projections for guidance, monitoring, and evaluating the surgical result. C-arm positioning is usually performed by hand, involving repeated or even continuous fluoroscopy at a cost of radiation exposure and time. We propose to automate this procedure and estimate the pose update for C-arm repositioning directly from a first X-ray without the need for a patient-specific computed tomography scan (CT) or additional technical equipment. Our method is trained on digitally reconstructed radiographs (DRRs) which uniquely provide ground truth labels for an arbitrary number of training examples. The simulated images are complemented with automatically generated segmentations, landmarks, and with simulated k-wires and screws. To successfully achieve a transfer from simulated to real X-rays, and also to increase the interpretability of results, the pipeline was designed to closely reflect the actual clinical decision-making process followed by spinal neurosurgeons. It explicitly incorporates steps such as region-of-interest (ROI) localization, detection of relevant and view-independent landmarks, and subsequent pose regression. The method was validated on a large human cadaver study simulating a real clinical scenario, including k-wires and screws. The proposed procedure obtained superior C-arm positioning accuracy of dθ=8.8°±4.2° average improvement (pt-test≪0.01), robustness, and generalization capabilities compared to the state-of-the-art direct pose regression framework.

Diferencias biomecánicas del gesto técnico de la media sentadilla libre en físico-culturistas profesionales y amateur / Diferenças biomecânicas do gesto técnico do meio-francho livre em musculturistas profissionais e iniciantes / Biomechanical differences of the technical gesture of the free half squat in professional and amateur bodybuilders

RESUMEN El perfeccionamiento de la técnica deportiva tiene como premisa comparar los valores del movimiento motriz, esta debe ser caracterizada para corregir errores detectados como parte del proceso de dirección del entrenamiento deportivo. Se pone énfasis en los deportes eminentemente técnicos, como es el caso del entrenamiento del fisiculturismo. En tal sentido, la presente investigación tuvo como objetivo analizar la técnica de la media sentadilla en fisiculturistas profesionales y amateurs como método empírico (medición específica del deporte). La investigación es descriptiva-explicativa de orden correlacional. Se correlacionan seis variables de interés (X1: ángulo de la articulación del hombro; X2: ángulo de la articulación de la cadera; X3: Velocidad máxima alcanzada; X4: aceleración máxima alcanzada; X5: centro de gravedad en X; X6: centro de gravedad en Y). Las medias establecen diferencias entre grupos independientes, tanto en la variable X1 (Grupo 1: ≈66°; grupo 2: H"70°; p=0.247), la X2 (grupo 1: ≈73°; grupo 2: ≈86°; p=0.002), La X3 (grupo 1:≈1.03m/s; grupo 2: ≈1.36m/s; p=0.017), la X4 (grupo 1: ≈2.93m/s2; grupo 2: ≈4.78m/s2; p=0.011), la X5 (grupo 1: ≈0.43m; grupo 2: ≈0.65m; p=0.000), y la X6 (grupo 1: ≈0.61m; grupo 2: ≈0.83m; p=0.000). El grupo 1 posee una técnica más efectiva, mientras que los amateurs poseen menor eficiencia en el movimiento biomecánico dada su inexperiencia, se muestran valores altos en velocidad y aceleración, se incluyen ángulos de movimiento como el de cadera.

RESUMO A melhoria da técnica desportiva baseia-se na premissa de comparar os valores do movimento motor, que deve ser caracterizada a fim de corrigir erros detectados como parte do processo de gestão do treino desportivo. A tónica é colocada no desporto eminentemente técnico, como é o caso do treino de musculação. Neste sentido, o objectivo desta investigação era analisar a técnica de meio agachamento em musculturistas profissionais e iniciantes como um método empírico (medição específica do desporto). A investigação é descritiva-explicativa da ordem correlativa. Seis variáveis de interesse estão correlacionadas (X1: ângulo da articulação do ombro; X2: ângulo da articulação da anca; X3: velocidade máxima alcançada; X4: aceleração máxima alcançada; X5: centro de gravidade em X; X6: centro de gravidade em Y). Os meios estabelecem diferenças entre grupos independentes, tanto na variável X1 (Grupo 1: ≈66°; grupo 2: ≈70°; p=0,247), a X2 (grupo 1: ≈73°; grupo 2: ≈86°; p=0,002), a X3 (grupo 1: ≈1. 03m/s; grupo 2: ≈1.36m/s; p=0.017), o X4 (grupo 1: ≈2.93m/s2; grupo 2: ≈4.78m/s2; p=0.011), o X5 (grupo 1: ≈0.43m; grupo 2: ≈0.65m; p=0.000), e o X6 (grupo 1: ≈0.61m; grupo 2: ≈0.83m; p=0.000). O grupo 1 tem uma técnica mais eficaz, enquanto os iniciantes têm uma eficiência de movimento biomecânico mais baixa devido à sua inexperiência, eles mostram menos eficiência no movimento biomecânico. Dada a sua inexperiência, são mostrados valores elevados em velocidade e aceleração, e são incluídos ângulos de movimento como o ângulo da anca.

ABSTRACT The improvement of the sports technique is premised on comparing the values of the motor movement, this must be characterized to correct errors detected as part of the sports training management process. Emphasis is placed on highly technical sports, such as bodybuilding training. In this sense, the present research aimed to analyze the half-squat technique in professional and amateur bodybuilders as an empirical method (sport-specific measurement). The research is descriptive-explanatory of correlational order. Six variables of interest are correlated (X1: shoulder joint angle; X2: hip joint angle; X3: maximum speed reached; X4: maximum acceleration reached; X5: center of gravity in X; X6: center of gravity in Y). The means establish differences between independent groups, both in variable X1 (group 1: ≈66°; group 2: ≈70°; p=0.247 ), X2 (group 1: ≈73°; group 2: ≈86°; p=0.002 ), X3 (group 1: ≈1.03m/s; group 2:≈1.36m/s; p=0.017 ), X4 (group 1: ≈2.93m/s2; group 2: ≈4.78m/s2; p=0.011 ), X5 (group 1: ≈0.43m; group 2:≈0.65m; p=0.000 ), and X6 (group 1: ≈0.61m; group 2: ≈0.83m; p =0.000 ). Group 1 has a more effective technique, while the amateurs have less efficiency in biomechanical movement due to their inexperience, high values are shown in speed and acceleration, movement angles such as hip angles are included.

Condición física de jóvenes aspirantes a pruebas de ingreso en escuelas militares ecuatorianas: estudio en dos grupos independientes / Aptidão física dos jovens candidatos aos exames de admissão nas escolas militares equatorianas: um estudo em dois grupos independentes / Physical fitness of young applicants for admission tests in Ecuadorian military schools: study in two independent groups

RESUMEN Anualmente, se abren convocatorias para jóvenes aspirantes a las diferentes escuelas de formación militar; para ello, existen ciertos requisitos para la selección del personal más cualificado para el acceso a estas instituciones. Entre ellos, diversas exigencias relacionadas con la condición física. Se plantea como objetivo de la investigación determinar los niveles y diferencias de la condición física entre dos grupos independientes de aspirantes a pruebas de ingreso de una escuela militar ecuatoriana. El estudio es descriptivo-correlacional con enfoque cuantitativo, realizado en una población de (N=40) jóvenes aspirantes a una Escuela Educativa Militar con una similitud de condiciones. Estos se clasifican en dos grupos independientes con 20 integrantes cada una (LN: Liceo Naval; CNC: Colegio Nacional Conocoto). La condición física fue evaluada mediante tres pruebas del Ejercito Nacional del Ecuador. En función de correlacionar datos, se utilizó la prueba paramétrica t de Student para muestras independientes (p≤0.05) en los test de flexión y extensión de codo y cadera y el test de resistencia en 3219 m. Existieron diferencias significativas entre los dos grupos evaluados en cada test (p=0.000), los cuales fueron mejores las medias en el grupo de aspirantes LN frente al grupo CNC. Específicamente, el Liceo Naval presentó mejores indicadores de capacidad física y, en sentido general, se identificó una carencia de condición física por parte de los aspirantes de las dos escuelas independientes, caracterizados por bajos niveles de actividad física. Este aspecto que repercute negativamente en los resultados de las pruebas de ingreso a academias militares ecuatorianas.

RESUMO A cada ano, há convites para inscrições de jovens candidatos às diversas escolas de treinamento militar, e há certos requisitos para a seleção do pessoal mais qualificado para o acesso a essas instituições. Estes incluem vários requisitos relacionados à condição física. O objetivo da pesquisa é determinar os níveis e diferenças nas condições físicas entre dois grupos independentes de candidatos a exames de admissão a uma escola militar equatoriana. O estudo é descritivo-correlacional com uma abordagem quantitativa, realizado em uma população de (N=40) jovens candidatos a uma Escola de Educação Militar com condições similares. Estes foram classificados em dois grupos independentes com 20 membros cada (LN: Liceo Naval; CNC: Colégio Nacional Conocoto). A aptidão física foi avaliada por meio de três testes do Exército Nacional do Equador. A fim de correlacionar os dados, o teste t de Student paramétrico para amostras independentes (p≤0.05) foi usado para os testes de flexão e extensão de cotovelo e quadril e o teste de resistência a 3219m. Houve diferenças significativas entre os dois grupos avaliados em cada teste (p=0,000), com o grupo candidato LN tendo melhores meios do que o grupo CNC. Especificamente, o Liceo Naval tinha melhores indicadores de capacidade física e, em um sentido geral, foi identificada uma falta de aptidão física nos candidatos das duas escolas independentes, caracterizada por baixos níveis de atividade física. Este aspecto tem um impacto negativo sobre os resultados dos exames de ingresso nas academias militares equatorianas.

ABSTRACT Annually, calls are opened for young applicants to the different military training schools; for this, there are certain requirements for the selection of the most qualified personnel for access to these institutions. Among them, various demands related to physical fitness. The objective of the research is to determine the levels and differences in physical fitness between two independent groups of applicants for entrance tests at an Ecuadorian military school. The study is descriptive-correlational with a quantitative approach, carried out in a population of (N=40) young people aspiring to a Military Educational School with similar fitness. These are classified into two independent groups with 20 members each (LN: Liceo Naval; CNC: Colegio Nacional Conocoto). The physical fitness was evaluated through three tests of the National Army of Ecuador. In order to correlate data, the parametric Student's t test was used for independent samples (p≤0.05) in the elbow and hip flexion and extension tests and the 3219 m endurance test. There were significant differences between the two groups evaluated in each test (p=0.000), which were better means in the group of LN applicants compared to the CNC group. Specifically, the Liceo Naval presented better indicators of physical fitness and, in general, a lack of physical fitness was identified by the applicants of the two independent schools, characterized by low levels of physical activity. This aspect has a negative impact on the results of the admission tests to Ecuadorian military academies.

Spectral organ fingerprints for machine learning-based intraoperative tissue classification with hyperspectral imaging in a porcine model.

Visual discrimination of tissue during surgery can be challenging since different tissues appear similar to the human eye. Hyperspectral imaging (HSI) removes this limitation by associating each pixel with high-dimensional spectral information. While previous work has shown its general potential to discriminate tissue, clinical translation has been limited due to the method's current lack of robustness and generalizability. Specifically, the scientific community is lacking a comprehensive spectral tissue atlas, and it is unknown whether variability in spectral reflectance is primarily explained by tissue type rather than the recorded individual or specific acquisition conditions. The contribution of this work is threefold: (1) Based on an annotated medical HSI data set (9059 images from 46 pigs), we present a tissue atlas featuring spectral fingerprints of 20 different porcine organs and tissue types. (2) Using the principle of mixed model analysis, we show that the greatest source of variability related to HSI images is the organ under observation. (3) We show that HSI-based fully-automatic tissue differentiation of 20 organ classes with deep neural networks is possible with high accuracy (> 95%). We conclude from our study that automatic tissue discrimination based on HSI data is feasible and could thus aid in intraoperative decisionmaking and pave the way for context-aware computer-assisted surgery systems and autonomous robotics.

Robust deep learning-based semantic organ segmentation in hyperspectral images.

Semantic image segmentation is an important prerequisite for context-awareness and autonomous robotics in surgery. The state of the art has focused on conventional RGB video data acquired during minimally invasive surgery, but full-scene semantic segmentation based on spectral imaging data and obtained during open surgery has received almost no attention to date. To address this gap in the literature, we are investigating the following research questions based on hyperspectral imaging (HSI) data of pigs acquired in an open surgery setting: (1) What is an adequate representation of HSI data for neural network-based fully automated organ segmentation, especially with respect to the spatial granularity of the data (pixels vs. superpixels vs. patches vs. full images)? (2) Is there a benefit of using HSI data compared to other modalities, namely RGB data and processed HSI data (e.g. tissue parameters like oxygenation), when performing semantic organ segmentation? According to a comprehensive validation study based on 506 HSI images from 20 pigs, annotated with a total of 19 classes, deep learning-based segmentation performance increases - consistently across modalities - with the spatial context of the input data. Unprocessed HSI data offers an advantage over RGB data or processed data from the camera provider, with the advantage increasing with decreasing size of the input to the neural network. Maximum performance (HSI applied to whole images) yielded a mean DSC of 0.90 ((standard deviation (SD)) 0.04), which is in the range of the inter-rater variability (DSC of 0.89 ((standard deviation (SD)) 0.07)). We conclude that HSI could become a powerful image modality for fully-automatic surgical scene understanding with many advantages over traditional imaging, including the ability to recover additional functional tissue information. Our code and pre-trained models are available at https://github.com/IMSY-DKFZ/htc.

SIMPA: an open-source toolkit for simulation and image processing for photonics and acoustics.

SIGNIFICANCE: Optical and acoustic imaging techniques enable noninvasive visualisation of structural and functional properties of tissue. The quantification of measurements, however, remains challenging due to the inverse problems that must be solved. Emerging data-driven approaches are promising, but they rely heavily on the presence of high-quality simulations across a range of wavelengths due to the lack of ground truth knowledge of tissue acoustical and optical properties in realistic settings. AIM: To facilitate this process, we present the open-source simulation and image processing for photonics and acoustics (SIMPA) Python toolkit. SIMPA is being developed according to modern software design standards. APPROACH: SIMPA enables the use of computational forward models, data processing algorithms, and digital device twins to simulate realistic images within a single pipeline. SIMPA's module implementations can be seamlessly exchanged as SIMPA abstracts from the concrete implementation of each forward model and builds the simulation pipeline in a modular fashion. Furthermore, SIMPA provides comprehensive libraries of biological structures, such as vessels, as well as optical and acoustic properties and other functionalities for the generation of realistic tissue models. RESULTS: To showcase the capabilities of SIMPA, we show examples in the context of photoacoustic imaging: the diversity of creatable tissue models, the customisability of a simulation pipeline, and the degree of realism of the simulations. CONCLUSIONS: SIMPA is an open-source toolkit that can be used to simulate optical and acoustic imaging modalities. The code is available at: https://github.com/IMSY-DKFZ/simpa, and all of the examples and experiments in this paper can be reproduced using the code available at: https://github.com/IMSY-DKFZ/simpa_paper_experiments.

Band selection for oxygenation estimation with multispectral/hyperspectral imaging.

Multispectral imaging provides valuable information on tissue composition such as hemoglobin oxygen saturation. However, the real-time application of this technique in interventional medicine can be challenging due to the long acquisition times needed for large amounts of hyperspectral data with hundreds of bands. While this challenge can partially be addressed by choosing a discriminative subset of bands, the band selection methods proposed to date are mainly restricted by the availability of often hard to obtain reference measurements. We address this bottleneck with a new approach to band selection that leverages highly accurate Monte Carlo (MC) simulations. We hypothesize that a so chosen small subset of bands can reproduce or even improve upon the results of a quasi continuous spectral measurement. We further investigate whether novel domain adaptation techniques can address the inevitable domain shift stemming from the use of simulations. Initial results based on in silico and in vivo experiments suggest that 10-20 bands are sufficient to closely reproduce results from spectral measurements with 101 bands in the 500-700 nm range. The investigated domain adaptation technique, which only requires unlabeled in vivo measurements, yielded better results than the pure in silico band selection method. Overall, our method could guide development of fast multispectral imaging systems suited for interventional use without relying on complex hardware setups or manually labeled data.

Diferencias biomecánicas en la patada chigo-Chagüi con pierna delantera entre taekwondocas principiantes y avanzados

El análisis de la técnica deportiva entre diferentes niveles de rendimiento sirve para establecer comparaciones metodológicas que tributan al perfeccionamiento del rendimiento motriz especializado, incluidos los deportes eminentemente técnico-tácticos. En tal sentido, el objetivo de la investigación es analizar las diferencias biomecánicas entre deportistas profesionales y amateurs de taekwondo en la realización de la patada Chigo-Chagüi con pierna delantera. Se estudiaron dos grupos independientes, Deportistas Principiantes (DPRI) 15 principiantes y Deportistas Profesionales (DPRO): 15 avanzados o profesionales), se estudiaron indicadores de Velocidad, Ángulo de Flexión y Centro de Gravedad y se estableció una comparación. Se determinó un ángulo inicial de DPRO =28,4° y DPRI: 27,34° (p=0.309) y un ángulo de impacto de DPRI= 117,93º y DPRO=129,2º (p=0.001) y un ángulo final de DPRI=31,34º y DPRO=26,34º (p=0.057), con un tiempo de ejecución de la patada de DPRO=1312ms y DPRI=1462 ms (p=0.009), una velocidad máxima de DPRO=6,86 m/s y DPRI=5,47 m/s (p=0.003) y una aceleración promedio de DPRO=48,35 m/s2 y DPRI=36,55 m/s2 (p=0.029), siendo el centro de gravedad para el punto de impacto en Eje X sin diferencias significativas (p=0.506) y en el Eje y con diferencias significativas entre grupos independientes (p=0.029). Las diferencias entre deportistas avanzados y principiantes en la patada chigo-chagüi con pierna delantera suelen ser notables en la mayoría de los indicadores analizados, siendo el nivel del atleta un indicador que permite describir las deficiencias técnicas.

A análise da técnica desportiva entre diversos níveis de desempenho serve para estabelecer comparações metodológicas que contribuirão para a melhoria do desempenho motor especializado, nomeadamente dos desportos eminentemente técnico-tácticos. Neste sentido, o propósito da investigação é analisar as diferenças biomecânicas entre os atletas profissionais e os iniciantes de taekwondo no desempenho do pontapé Chigo-Chagüi com a perna dianteira. Foram estudados dois grupos independentes, Atletas Principiantes (DPRI) 15 principiantes e Atletas Profissionais (DPRO): 15 avançados ou profissionais), foram estudados indicadores de Velocidade, Ângulo de Flexibilidade e Centro de Gravidade e foi estabelecida uma comparação. Um ângulo inicial do DPRO=28,4° e DPRI: 27,34° (p=0,309) e um ângulo de impacto do DPRI= 117,93º e DPRO=129,2º (p=0,001) e um ângulo final do DPRI=31,34º e DPRO=26,34º (p=0,057), com um tempo de pontapé de execução do DPRO=1312ms e DPRI=1462 ms (p=0,009), um tempo máximo de pontapé de execução do DPRO=1312ms e DPRI=1462 ms (p=0 009), uma velocidade máxima de DPRO=6,86 m/s e DPRI=5,47 m/s (p=0,003) e uma aceleração média de DPRO=48,35 m/s2 e DPRI=36,55 m/s2 (p=0,029), sendo o centro de gravidade para o ponto de colisão no Eixo X sem diferenças significativas (p=0,506) e no Eixo y com diferenças significativas entre grupos independentes (p=0,029). As diferenças entre atletas avançados e iniciantes no pontapé de chigo-Chagüi com a perna dianteira são geralmente notáveis na maioria dos indicadores analisados, sendo o nível do atleta um indicador que permite descrever as deficiências técnicas.

The analysis of sports technique between different performance levels serves to establish methodological comparisons that contribute to the improvement of specialized motor performance, including eminently technical-tactical sports. In this sense, the objective of the research is to analyze the biomechanical differences between professional and amateur taekwondo athletes in the performance of the Chigo-Chagüi kick with front leg. Two independent groups were studied, 15 Beginner Athletes (DPRI in Spanish) and15 Professional or advanced Athletes (DPRO in Spanish); indicators of Speed, Flexion Angle and Center of Gravity were studied and a comparison was established. An initial angle of DPRO=28.4° and DPRI: 27.34° (p=0.309) and an impact angle of DPRI= 117.93º and DPRO=129.2º (p=0.001) and a final angle of DPRI=31.34º and DPRO=26.34º (p=0.057) were determined, with a kick execution time of DPRO=1312ms and DPRI=1462 ms (p=0.009), a maximum velocity of DPRO=6.86 m/s and DPRI=5.47 m/s (p=0.003) and an average acceleration of DPRO=48.35 m/s2 and DPRI=36.55 m/s2 (p=0.029), being the center of gravity for the impact point in Axis X with no significant differences (p=0.506) and in Axis Y with significant differences between independent groups (p=0.029). The differences between advanced and beginner athletes in the chigo-chagüi kick with front leg are usually remarkable in most of the indicators analyzed, being the level of the athlete an indicator that allows describing the technical deficiencies.

Higher viral load and infectivity increase risk of aerosol transmission for Delta and Omicron variants of SARS-CoV-2.

BACKGROUND: Airborne transmission of SARS-CoV-2 is an important route of infection. For the wildtype (WT) only a small proportion of those infected emitted large quantities of the virus. The currently prevalent variants of concern, Delta (B1.617.2) and Omicron (B.1.1.529), are characterized by higher viral loads and a lower minimal infective dose compared to the WT. We aimed to describe the resulting distribution of airborne viral emissions and to reassess the risk estimates for public settings given the higher viral load and infectivity. METHOD: We reran the Monte Carlo modelling to estimate viral emissions in the fine aerosol size range using available viral load data. We also updated our tool to simulate indoor airborne transmission of SARS-CoV-2 by including a CO2 calculator and recirculating air cleaning devices. We also assessed the consequences of the lower critical dose on the infection risk in public settings with different protection strategies. RESULTS: Our modelling suggests that a much larger proportion of individuals infected with the new variants are high, very high or super-emitters of airborne viruses: for the WT, one in 1,000 infected was a super-emitter; for Delta one in 30; and for Omicron one in 20 or one in 10, depending on the viral load estimate used. Testing of the effectiveness of protective strategies in view of the lower critical dose suggests that surgical masks are no longer sufficient in most public settings, while correctly fitted FFP2 respirators still provide sufficient protection, except in high aerosol producing situations such as singing or shouting. DISCUSSION: From an aerosol transmission perspective, the shift towards a larger proportion of very high emitting individuals, together with the strongly reduced critical dose, seem to be two important drivers of the aerosol risk, and are likely contributing to the observed rapid spread of the Delta and Omicron variants of concern. Reducing contacts, always wearing well-fitted FFP2 respirators when indoors, using ventilation and other methods to reduce airborne virus concentrations, and avoiding situations with loud voices seem critical to limiting these latest waves of the COVID-19 pandemic.

Carga de la enfermedad y costos en salud por la exposición a mercurio: revisión de alcance / Burden of disease and health costs from mercury exposure: Scoping review

Resumen Introducción: El mercurio circula por el aire; persiste en suelos, sedimentos y agua, y causa efectos en la salud humana. Las mujeres en edad fértil y los neonatos son la población más vulnerable. Objetivo: Analizar las evidencias sobre la carga de enfermedad ocasionada por la exposición a mercurio, así como el impacto económico sobre el sistema de salud. Metodología: Revisión de alcance de la literatura, de las bases de datos PUBMED y EPISTEMONIKOS, búsqueda manual de documentos técnicos de entidades oficiales de diferentes continentes. Resultados: Se identificaron 311 registros en bases de datos y 4 en búsqueda manual en entidades oficiales; 19 artículos fueron incluidos. Discusión: Predomina la afectación del desarrollo neurológico y cognitivo en niños de madres expuestas y lactantes. Los costos se midieron por la pérdida del coeficiente intelectual. Conclusión: Efectos en salud por la exposición a metilmercurio se traducen en gastos para la sociedad y los sistemas de salud.

Abstract Introduction: Mercury circulates through the air, persists in soils, sediments and water, and can affect human health. Women of childbearing age and newborns are the most vulnerable population. Objective: To analyze the evidence on the burden of disease caused by mercury exposure, as well as the economic impact on the health system. Methodology: Review of the literature, PUBMED and EPISTEMONIKOS databases, manual search of technical documents of official entities from different continents. Results: A total of 311 records were identified in databases and four in manual searches from official entities; 19 articles were included. Discussion: Neurological and cognitive development in children of exposed mothers and infants are more predominant. Costs were measured by IQ loss. Conclusion: Health effects of methylmercury exposure translate into costs for society and health systems.

Using GIS to Estimate Population at Risk Because of Residence Proximity to Asbestos Processing Facilities in Colombia.

The recent enactment of the law banning asbestos in Colombia raises a significant number of challenges. The largest factories that have historically processed asbestos include five asbestos-cement facilities located in the cities of Sibaté (Cundinamarca), Cali (Valle del Cauca), and Barranquilla (Atlántico), and Manizales (Caldas), which has two, as well as a friction products facility in Bogotá D.C. An asbestos chrysotile mine has also operated in Colombia since 1980 in Campamento (Antioquia). In the framework of developing the National Asbestos Profile for Colombia, in this study, we estimated the population residing in the vicinity of asbestos processing plants or the mine and, therefore, potentially at risk of disease. Using a geographic information system, demographic data obtained from the last two general population censuses were processed to determine the number of people living within the concentric circles surrounding the asbestos facilities and the mine. In previous studies conducted in different countries of the world, an increased risk of asbestos-related diseases has been reported for people living at different distance bands from asbestos processing facilities. Based on these studies, circles of 500, 1000, 2000, 5000, and 10,000 m radii, centered on the asbestos processing facilities and the mine that operated in Colombia, were combined with the census data to estimate the number of people living within these radii. Large numbers of people were identified. It is estimated that in 2005, at the country level, 10,489 people lived within 500 m of an asbestos processing facility or mine. In 2018, and within a distance of 10,000 m, the number of people was 6,724,677. This information can aid public health surveillance strategies.

Influencia de la capacidad física de velocidad en la potencia de salto del voleibol escolar / Influência da capacidade física da velocidade no salto em potência no voleibol escolar / Influence of physical speed capacity on jumping power in volleyball, school category

RESUMEN El entrenamiento integrado evidencia la necesidad de implementar varios componentes de la preparación para lograr mayores rendimientos. Es conocido la importancia que reviste el método pliométrico para potenciar la habilidad motriz salto, pero otras capacidades como la velocidad pudieran influir directa o indirectamente. En tal sentido, se planteó como objetivo determinar si la capacidad física de velocidad influye en la potencia de salto del voleibolista de categoría escolar. Esta investigación es de tipo cuasi-experimental, de orden correlativa, que estudia la población de voleibolistas de la Unidad Educativa La Salle, (grupo 1 experimental: 26 estudiantes) y la Unidad Educativa Oswaldo Lombeyda (grupo 2 control: 25 estudiantes), género masculino y categoría 13-14 años. Los grupos se sometieron al mismo entrenamiento, excepto el grupo experimental que se le implementó una estrategia de trabajo con estímulos físicos, que prioriza cargas de velocidad para miembros inferiores. Las medias en la habilidad de salto se incrementaron significativamente para las muestras relacionadas (p=0.000) en ambos grupos (grupo 1: 4.38 cm. a 6.23 cm.; grupo 2: 4.40 cm. a 6.04 cm) como parte del postest, lo cual no muestra diferencias entre grupos independientes (pretest: k=0.894; postest: k=0.605), mientras que la capacidad de velocidad para grupos relacionados se incrementaron significativamente (p=0.000) a favor del postest, no existiendo diferencias en el pretest (k=0.183) y sí en el postest, a favor del grupo experimental (k=0.009). Se demuestra una potenciación del salto del voleibolista escolar, dada la aplicación del método pliométrico, método de repeticiones y test de valoraciones de rendimiento.

RESUMO O treino integrado mostra a necessidade de implementar vários componentes da preparação para alcançar um maior desempenho. É conhecida a importância do método pliométricos para melhorar a habilidade motora de salto, mas outras capacidades como a velocidade podem influenciar direita ou indiretamente. Neste sentido, o objectivo é determinar se a capacidade física da velocidade e sua influência no poder de salto do jogador de voleibol da categoria escolar. Esta investigação é de tipo quase experimental, de ordem correlativa, que estuda a população de jogadores de voleibol da Unidade Educativa La Salle (grupo experimental 1: 26 estudantes) e da Unidade Educativa Oswaldo Lombeyda (grupo de controlo 2: 25 estudantes), sexo masculino e categoria 13-14 anos de idade. Os grupos foram submetidos à mesma formação, exceto para o grupo experimental que foi implementado uma estratégia de trabalho com estímulos físicos, que dá prioridade às cargas de velocidade para os membros inferiores. Os meios em capacidade de salto aumentaram significativamente para as amostras relacionadas (p=0,000) em ambos os grupos (grupo 1: 4,38 cm. a 6,23 cm.; grupo 2: 4,40 cm. a 6,04 cm.) como parte do pós-teste, que não mostra diferenças entre os grupos independentes (pré-teste: k=0. 894; posttest: k=0,605), enquanto a capacidade de velocidade para grupos relacionados aumentou significativamente (p=0,000) a favor do posttest, sem diferenças no pré-teste (k=0,183) e no posttest, a favor do grupo experimental (k=0,009). Demonstra-se uma potenciação do salto do jogador de voleibol escolar, dada a aplicação do método pliométrico, método de repetições e teste de avaliação do desempenho.

ABSTRACT Integrated training demonstrates the need to implement various components of preparation to achieve higher performance. The importance of the plyometric method to enhance jumping ability is known, but other capacity such as speed could have a direct or indirect influence. In this sense, the objective is to determine whether the physical capacity for speed influences the jumping power of the school-class volleyball player. Quasi-experimental research of a correlative order that study the population of volleyball players from the "La Salle" Educational Unit, (Experimental Group 1: 26 students) and the "Oswaldo Lombeyda" Educational Unit (Control Group 2: 25 students), male gender, category 13-14 years. The groups underwent the same training, except that in the experimental group it was implemented a work strategy with physical stimuli, prioritizing speed loads for lower limbs. The means in jumping ability were significantly increased for the related samples (p = 0.000) in both groups (Group 1: 4.38cm to 6.23cm; Group 2: 4.40cm to 6.04cm) as part of posttest, there were no differences between independent groups (Pretest: k = 0.894; Posttest: k = 0.605), while the speed capacity for related groups increased significantly (p = 0.000) in posttest favor, there were no pretest differences (k = 0.183), with differences in the posttest in favor of the experimental group (k = 0.009). It is demonstrated a potentiation of the school volleyball player's jump, given the application of the plyometric method, repetition method and performance assessment test.