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This paper describes a dataset of convective systems (CSs) associated with hailstorms over Brazil tracked using GOES-16 Advanced Baseline Imager (ABI) measurements and the Tracking and Analysis of Thunderstorms (TATHU) tool. The dataset spans from June 5, 2018, to September 30, 2023, providing five-year period of storm activity. CSs were detected and tracked using the ABI's clean IR window brightness temperature at 10.3 µm, projected on a 2 km x 2 km Lat-Lon WGS84 grid. Systems were identified using a brightness temperature (BT) threshold of 235 K, conducive to detecting convective clusters with larger area and excluding smaller or non-convective cells such as groups of thin Cirrus clouds. Each detected CS was treated as an object, containing geographic boundaries and raster statistics such as BT's mean, minimum, standard deviation, and count of data points within the CS polygon, which serves as proxy for size estimates. The life cycle of each system was tracked based on a 10 % overlap area criterion, ensuring continuity, unless disrupted by dissociative or associative events. Then, the tracked CSs were filtered for intersections in space and time with verified ground reports of hail, from the Prevots group. The matches were then exported to a database with SpatiaLite enabled data format to facilitate spatial data queries and analyses. This database is structured to support advanced research in severe weather events, in particular hailfall. This setting allows for extensive temporal and spatial analyses of convective systems, making it useful for meteorologists, climate scientists, and researchers in related fields . The inclusion of detailed tracking information and raster statistics offers potential for diverse applications, including climate model validation, weather prediction enhancements, and studies on the climatological impact of severe weather phenomena in Brazil.

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Inoculation of Azospirillum in maize has become a standard practice in Latin America. However, information on the behavior and population survival of the Azospirillum post-inoculation is scarce, making standardization difficult and generating variations in inoculation efficiency across assays. In this study, we tracked the colonization of three agriculturally relevant Azospirillum strains (Ab-V5, Az39, and the ammonium excreting HM053) after different inoculation methods in maize crops by qPCR. Besides, we assessed their ability to promote maize growth by measuring biometric parameters after conducting a greenhouse essay over 42 days. Inoculated plants exhibited Azospirillum population ranging from 103 to 107 cells plant-1 throughout the experiment. While all strains efficiently colonized roots, only A. argentinense Az39 demonstrated bidirectional translocation between roots and shoots, which characterizes a systemic behavior. Optimal inoculation methods for plant growth promotion varied among strains: soil inoculation promoted the best maize growth for the Ab-V5 and Az39 strains, while seed inoculation proved most effective for HM053. The findings of this study demonstrate that the inoculation method affects the behavior of Azospirillum strains and their effectiveness in promoting maize growth, thereby guiding practices to enhance crop yield.

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OBJECTIVE: Video-based eye tracking was used to investigate saccade, pupil, and blink abnormalities among patients with Huntington's disease (HD) who watched sequences of short videos. HD, an autosomal dominant neurodegenerative disorder resulting from a CAG mutation on chromosome 4, produces motor and cognitive impairments including slow or irregular eye movements, which have been studied using structured tasks. METHODS: To explore how HD affects eye movements under instruction free conditions, we assessed 22 HD patients and their age matched controls in a 10-minute video-based free viewing task. RESULTS: Patients with HD experienced a significant reduction in saccade exploration rate following video clip transitions, an increase in pupil reactions to luminance changes after clip transitions, and a significant higher blink rate throughout the task compared to the control group. CONCLUSIONS: These results show that HD has a significant impact on how patients visually explore and respond to their environment under unconstrained and ecologically natural conditions. SIGNIFICANCE: Eye tracking in HD patients revealed saccadic, pupil, and blink abnormalities in early HD patients, suggestive of brain circuitry abnormalities that probably involve brain stem deficits. Further research should explore the impact of these changes on the quality of life of the patients affected by the disease.

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Jataí is a pollinator of some crops; therefore, its sustainable management guarantees quality in the ecosystem services provided and implementation in precision agriculture. We acquired videos of natural and artificial hives in urban and rural environments with a camera positioned at the hive entrance. In this way, we obtained videos of the entrance of several colonies for multiple bee tracking and removed images from the videos for bee detectors. This data, their respective labels, and metadata make up the dataset. The dataset displays potential for utilization in computer vision tasks such as comparative studies of deep learning models. They can also integrate intelligent monitoring systems for natural and artificial hives.

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The increased environmental presence of micro-/nanoplastics (MNPLs) and the potential health risks associated with their exposure classify them as environmental pollutants with special environmental and health concerns. Consequently, there is an urgent need to investigate the potential risks associated with secondary MNPLs. In this context, using "true-to-life" MNPLs, resulting from the laboratory degradation of plastic goods, may be a sound approach. These non-commercial secondary MNPLs must be labeled to track their presence/journeys inside cells or organisms. Because the cell internalization of MNPLs is commonly analyzed using fluorescence techniques, the use of fluorescent dyes may be a sound method to label them. Five different compounds comprising two chemical dyes (Nile Red and Rhodamine-B), one optical brightener (Opticol), and two industrial dyes (Amarillo Luminoso and iDye PolyPink) were tested to determine their potential for such applications. Using commercial standards of polystyrene nanoplastics (PSNPLs) with an average size of 170 nm, different characteristics of the selected dyes such as the absence of impact on cell viability, specificity for plastic staining, no leaching, and lack of interference with other fluorochromes were analyzed. Based on the overall data obtained in the wide battery of assays performed, iDye PolyPink exhibited the most advantages, with respect to the other compounds, and was selected to effectively label "true-to-life" MNPLs. These advantages were confirmed using a proposed protocol, and labeling titanium-doped PETNPLs (obtained from the degradation of milk PET plastic bottles), as an example of "true-to-life" secondary NPLs. These results confirmed the usefulness of iDye PolyPink for labeling MNPLs and detecting cell internalization.

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BACKGROUND: This study investigates myocardial structural changes in stable coronary artery disease (CAD) patients with type 2 diabetes (T2D) using cardiac magnetic resonance (CMR) strain and T1 mapping. METHODS: A total of 155 stable CAD patients underwent CMR examination, including left ventricular (LV) morphology and function assessment, late gadolinium enhancement (LGE), and feature tracking (CMR-FT) for LV global longitudinal, circumferential, and radial strain. T1 mapping with extracellular volume (ECV) evaluation was also performed. RESULTS: Among the enrolled patients, 67 had T2D. Diabetic patients exhibited impaired LV strain and higher ECV compared to non-diabetics. Multivariate analysis identified T2D as an independent predictor of increased ECV and decreased strain. CONCLUSIONS: CMR-based strain and T1 mapping highlighted impaired myocardial contractility, elevated ECV, and potential interstitial fibrosis in diabetic patients with stable CAD. This suggests a significant impact of diabetes on myocardial health beyond CAD, emphasizing the importance of a comprehensive assessment in these individuals. TRIAL REGISTRATION: http://www.controlled-trials.com/ISRCTN09454308.

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Despite the effectiveness of antiretroviral therapy (ART), human immunodeficiency virus (HIV) infection remains a global public health concern. However, weaknesses in its management regarding access to integrated HIV care include treatment gaps and loss to follow-up (LTFU) from antiretroviral treatment (ART). This study aimed to characterize the epidemiological and clinical profiles of people living with HIV/AIDS (PLHA) in LTFU from HIV care in Campo Grande, Central Brazil. This retrospective cross-sectional study was conducted between January 2021 and April 2022 using secondary data from PLHA who had LTFU in Campo Grande. A total of 852 patients with PLHA were included in this study. The majority of participants in LTFU were male (63.1%), had a CD4 cell count > 200 cells/mm3 (68.2%), and had been treated for ≥ 3 months (86.4%). Only 287 (33.7%) participants had undetectable HIV viral load. Of the total number of patients who returned to treatment during the study period, 448 (54.3%) were LTFU-positive. The tracking strategy was not applied to 556 (65.26%) patients, and 44.4% of the participants had been in spontaneous demand. These results highlight the relevance of patient-centered interventions and the need to ensure early treatment and promote retention in care systems with consequent viral suppression, impacting the healthcare indicators of the population, with emphasis on health managers and stakeholders in HIV care.

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Uncertainties and discrepant results in identifying crucial areas for emotional facial expression recognition may stem from the eye tracking data analysis methods used. Many studies employ parameters of analysis that predominantly prioritize the examination of the foveal vision angle, ignoring the potential influences of simultaneous parafoveal and peripheral information. To explore the possible underlying causes of these discrepancies, we investigated the role of the visual field aperture in emotional facial expression recognition with 163 volunteers randomly assigned to three groups: no visual restriction (NVR), parafoveal and foveal vision (PFFV), and foveal vision (FV). Employing eye tracking and gaze contingency, we collected visual inspection and judgment data over 30 frontal face images, equally distributed among five emotions. Raw eye tracking data underwent Eye Movements Metrics and Visualizations (EyeMMV) processing. Accordingly, the visual inspection time, number of fixations, and fixation duration increased with the visual field restriction. Nevertheless, the accuracy showed significant differences among the NVR/FV and PFFV/FV groups, despite there being no difference in NVR/PFFV. The findings underscore the impact of specific visual field areas on facial expression recognition, highlighting the importance of parafoveal vision. The results suggest that eye tracking data analysis methods should incorporate projection angles extending to at least the parafoveal level.

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This study examined lexical-semantic processing in children with Developmental Language Disorder (DLD) during visually situated comprehension of real-time spoken words. Existing evidence suggests that children with DLD may experience challenges in lexical access and retrieval, as well as greater lexical competition compared to their peers with Typical Development (TD). However, the specific nature of these difficulties remains unclear. Using eye-tracking methodology, the study investigated the real-time comprehension of semantic relationships in children with DLD and their age-matched peers. The results revealed that, for relatively frequent nouns, both groups demonstrated similar comprehension of semantic relationships. Both groups favored the semantic competitor when it appeared with an unrelated visual referent. In turn, when the semantic competitor appeared with the visual referent of the spoken word, both groups disregarded the competitor. This finding shows that, although children with DLD usually present a relatively impoverished vocabulary, frequent nouns may not pose greater difficulties for them. While the temporal course of preference for the competitor or the referent was similar between the two groups, numerical, though non-significant, differences in the extension of the clusters were observed. In summary, this research demonstrates that monolingual preschoolers with DLD exhibit similar lexical access to frequent words compared to their peers with TD. Future studies should investigate the performance of children with DLD on less frequent words to provide a comprehensive understanding of their lexical-semantic abilities.

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Extracellular vesicles (EVs) are produced by all domains of life. In fungal pathogens, they participate in virulence mechanisms and/or induce protective immunity, depending on the pathogenic species. EVs produced by pathogenic members of the Cryptococcus genus mediate virulence, antifungal resistance, as well as humoral and cell-mediated immunity. The isolation of cryptococcal EVs has been laborious and time-consuming for years. In this chapter, we detail a fast protocol for the isolation and analysis of EVs produced by members of the Cryptococcus genus.

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Different tests measure text comprehension, including the cloze gap-filling test, often used for language learning. Different studies hypothesized cognitive strategies in this type of test and their relationship with working memory and performance. However, no study investigated the cloze test, working memory, and possible cognitive strategies, while performing the test. Therefore, this study aimed to identify cognitive visual strategies in the cloze test by applying an unsupervised algorithm and to analyze the relationship between these strategies with working memory and performance in the cloze test. Our sample consisted of 51 university students, the largest sample in studies of cognitive strategies with cloze tests. Participants answered an 11-item cloze test in a computer with eye-tracking, a verbal working memory test, and a visuospatial working memory test. Our analysis of participants' scanpath identified two main strategies: one with fewer toggles between text and word bank and fewer fixations than the other one, indicating the existence of a global strategy. Furthermore, a model predicting the efficiency of participants in the cloze test found that item complexity, using a global strategy, and higher scores of working memory were the most significant predictors. These results confirm the hypothesis of a global strategy being related to successfully achieving higher-order reading processes.

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Eukaryotic genomes store information on many levels, including their linear DNA sequence, the posttranslational modifications of its constituents (epigenetic modifications), and its three-dimensional folding. Understanding how this information is stored and read requires multidisciplinary collaborations from many branches of science beyond biology, including physics, chemistry, and computer science. Concurrent recent developments in all these areas have enabled researchers to image the genome with unprecedented spatial and temporal resolution. In this review, we focus on what single-molecule imaging and tracking of individual proteins in live cells have taught us about chromatin structure and dynamics. Starting with the basics of single-molecule tracking (SMT), we describe some advantages over in situ imaging techniques and its current limitations. Next, we focus on single-nucleosome studies and what they have added to our current understanding of the relationship between chromatin dynamics and transcription. In celebration of Robert Feulgen's ground-breaking discovery that allowed us to start seeing the genome, we discuss current models of chromatin structure and future challenges ahead.

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The COVID-19 pandemic presented numerous challenges that required immediate attention to mitigate its devastating consequences on a local and global scale. In March 2020, the Chilean government, along with health and science authorities, implemented a strategy aimed at generating relevant evidence to inform effective public health decisions. One of the key strengths of this strategy was the active involvement of the scientific community, employing transdisciplinary approaches to address critical questions and support political decision-making. The strategy promoted collaborations between the government, public and private institutions, and transdisciplinary academic groups throughout each phase of the pandemic. By focusing on pressing problems and questions, this approach formed the foundation of this report which reflects the collaborative effort throughout the pandemic of individuals from the Instituto de Sistemas Complejos de Ingeniería (ISCI), the Faculty of Medicine of the University of Chile, government authorities and industry. Early in the pandemic, it became crucial to gather evidence on how to minimize the impact of infection and disease while awaiting the availability of vaccines. This included studying the dynamics of SARS-CoV-2 infection in children, assessing the impact of quarantines on people's mobility, implementing strategies for widespread SARS-CoV-2 polymerase chain reaction (PCR) testing, and exploring pool testing for large populations. The urgent need to reduce disease severity and transmission posed a significant challenge, as it was essential to prevent overwhelming healthcare systems. Studies were conducted to predict ICU bed requirements at the local level using mathematical models. Additionally, novel approaches, such as using cellphone mobility-based technology to actively identify infected individuals, and to optimize population sampling, were explored following the first wave of the pandemic. Chile took early action in addressing vaccination through a high-level scientific board, before vaccines became available. Studies conducted during this period included population-based immunologic evaluations of different vaccines, which helped build confidence in the population and supported the need for booster doses and potential vaccination of children. These studies and collaborations, which will be discussed here, have provided valuable insights and will inform future approaches in a post-pandemic world. Importantly, highly conservative estimates indicate that 3,000 lives and more than 300 million USD were saved by this academic-public-private collaborative effort.

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Millimeter-wave (mmWave) radars attain high resolution without compromising privacy while being unaffected by environmental factors such as rain, dust, and fog. This study explores the challenges of using mmWave radars for the simultaneous detection of people and small animals, a critical concern in applications like indoor wireless energy transfer systems. This work proposes innovative methodologies for enhancing detection accuracy and overcoming the inherent difficulties posed by differences in target size and volume. In particular, we explore two distinct positioning scenarios that involve up to four mmWave radars in an indoor environment to detect and track both humans and small animals. We compare the outcomes achieved through the implementation of three distinct data-fusion methods. It was shown that using a single radar without the application of a tracking algorithm resulted in a sensitivity of 46.1%. However, this sensitivity significantly increased to 97.10% upon utilizing four radars using with the optimal fusion method and tracking. This improvement highlights the effectiveness of employing multiple radars together with data fusion techniques, significantly enhancing sensitivity and reliability in target detection.

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STUDY OBJECTIVES: The aim of this study was to develop a sleep staging classification model capable of accurately performing on different wearable devices. METHODS: Twenty-three healthy participants underwent a full-night type I polysomnography and used two device combinations: (A) flexible single-channel electroencephalogram (EEG) headband + actigraphy (n = 12) and (B) rigid single-channel EEG headband + actigraphy (n = 11). The signals were segmented into 30-second epochs according to polysomnographic stages (scored by a board-certified sleep technologist; model ground truth) and 18 frequency and time features were extracted. The model consisted of an ensemble of bagged decision trees. Bagging refers to bootstrap aggregation to reduce overfitting and improve generalization. To evaluate the model, a training dataset under 5-fold cross-validation and an 80-20% dataset split was used. The headbands were also evaluated without the actigraphy feature. Participants also completed a usability evaluation (comfort, pain while sleeping, and sleep disturbance). RESULTS: Combination A had an F1-score of 98.4% and the flexible headband alone of 97.7% (error rate for N1: combination A = 9.8%; flexible headband alone = 15.7%). Combination B had an F1-score of 96.9% and the rigid headband alone of 95.3% (error rate for N1: combination B = 17.0%; rigid headband alone = 27.7%); in both, N1 was more confounded with N2. CONCLUSIONS: We developed an accurate sleep classification model based on a single-channel EEG device, and actigraphy was not an important feature of the model. Both headbands were found to be useful, with the rigid one being more disruptive to sleep. Future research can improve our results by applying the developed model in a population with sleep disorders. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Name: Actigraphy, Wearable EEG Band and Smartphone for Sleep Staging; URL: https://clinicaltrials.gov/study/NCT04943562; Identifier: NCT04943562. CITATION: Melo MC, Vallim JRS, Garbuio S, et al. Validation of a sleep staging classification model for healthy adults based on 2 combinations of a single-channel EEG headband and wrist actigraphy. J Clin Sleep Med. 2024;20(6):983-990.

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Eye tracking has become increasingly applied in medical education research for studying the cognitive processes that occur during the performance of a task, such as image interpretation and surgical skills development. However, analysis and interpretation of the large amount of data obtained by eye tracking can be confusing. In this article, our intention is to clarify the analysis and interpretation of the data obtained from eye tracking. Understanding the relationship between eye tracking metrics (such as gaze, pupil and blink rate) and cognitive processes (such as visual attention, perception, memory and cognitive workload) is essential. The importance of calibration and how the limitations of eye tracking can be overcome is also highlighted.

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The utmost aim of regenerative medicine is to promote the regeneration of injured tissues using stem cells. Amniotic mesenchymal stem cells (AmMSCs) have been used in several studies mainly because of their easy isolation from amniotic tissue postpartum and immunomodulatory and angiogenic properties and the low level of rejection. These cells share characteristics of both embryonic/fetal and adult stem cells and are particularly advantageous because they do not trigger tumorigenic activity when injected into immunocompromised animals. The large-scale use of AmMSCs for cellular therapies would greatly benefit from fluorescence labeling studies to validate their tracking in future therapies. This study evaluated the fluorophore positivity, fluorescence intensity, and longevity of canine AmMSCs. For this purpose, canine AmMSCs from the GDTI/USP biobank were submitted to three labeling conditions, two commercial fluorophores [CellTrace CFSE Cell Proliferation kit - CTrace, and CellTracker Green CMFDA - CTracker (CellTracker Green CMFDA, CT, #C2925, Molecular Probes®; Life Technologies)] and green fluorescent protein (GFP) expression after lentiviral transduction, to select the most suitable tracer in terms of adequate persistence and easy handling and analysis that could be used in studies of domestic animals. Fluorescence was detected in all groups; however, the patterns were different. Specifically, CTrace and CTracker fluorescence was detected 6 h after labeling, while GFP was visualized no earlier than 48 h after transduction. Flow cytometry analysis revealed more than 70% of positive cells on day 7 in the CTrace and CTracker groups, while fluorescence decreased significantly to 10% or less on day 20. Variations between repetitions were observed in the GFP group under the present conditions. Our results showed earlier fluorescence detection and more uniform results across repetitions for the commercial fluorophores. In contrast, fluorescence persisted for more extended periods in the GFP group. These results indicate a promising direction for assessing the roles of canine AmMSCs in regenerative medicine without genomic integration.

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BACKGROUND: Premature newborns have a higher risk of abnormal visual development and visual impairment. OBJECTIVE: To develop a computational methodology to help assess functional vision in premature infants by tracking iris distances. METHODS: This experimental study was carried out with children up to two years old. A pattern of image capture with the visual stimulus was proposed to evaluate visual functions of vertical and horizontal visual tracking, visual field, vestibulo-ocular reflex, and fixation. The participants' visual responses were filmed to compose a dataset and develop a detection algorithm using the OpenCV library allied with FaceMesh for the detection and selection of the face, detection of specific facial points and tracking of the iris positions is done. A feasibility study was also conducted from the videos processed by the software. RESULTS: Forty-one children of different ages and diagnoses participated in the experimental study, forming a robust dataset. The software resulted in the tracking of iris positions during visual function evaluation stimuli. Furthermore, in the feasibility study, 8 children participated, divided into Pre-term and Term groups. There was no statistical difference in any visual variable analyzed in the comparison between groups. CONCLUSION: The computational methodology developed was able to track the distances traveled by the iris, and thus can be used to help assess visual function in children.

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OBJECTIVES: This study assessed laypeople's perceptions of orthodontist credibility based on malocclusions and whether these views affect their choice to seek treatment. Eye-tracking technology and questionnaires were utilized. MATERIALS AND METHODS: Ninety-five lay raters, through eye tracking and a questionnaire, assessed 12 images of orthodontists with malocclusions. Malocclusions were categorized by the Index Of Treatment Need (IOTN) as grade 1 (near ideal), 3 (anterior crowding), and 5 (with diastemas). Fixation points were recorded, and credibility was gauged via questionnaires. A Mentimeter word cloud was generated. RESULTS: IOTN 1 orthodontists were viewed as more credible than IOTN 3 (p < 0.001) and 5 (p < 0.001). Raters were more willing to receive treatment from IOTN 1 orthodontists. The focus for IOTN 1 was between eyes and mouth, while IOTN 3 and 5 were on the mouth. "Crooked teeth" and "spacing" were predominant in word clouds for IOTN 3 and 5. CONCLUSION: Orthodontists with an IOTN grade 1 rating were perceived as more competent, reliable, and professional, thus making it more likely for laypeople to choose them as their preferred providers. CLINICAL RELEVANCE: The smiles of professionals play a significant role in laypeople's decision to choose them as their orthodontist, and strategic utilization of social media can effectively deliver health information to a larger audience in a faster and more direct manner.

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Passive acoustic and Argos satellite telemetry are common methods for tracking marine species and are often used similarly to quantify space use. However, data-driven comparisons of these methods and their associated ecological inferences are limited. To address this, we compared temporal durations, spatial resolutions, financial costs and estimates of occurrence and range distributions for each tracking approach using nine juvenile green turtles (Chelonia mydas) in Bimini, Bahamas. Tracking durations were similar, although acoustic tracking provided higher spatiotemporal resolution than satellite tracking. Occurrence distributions (95%) estimated from satellite telemetry were 12 times larger than those from acoustic telemetry, while satellite range distributions (95%) were 89 times larger. While individuals generally remained within the extent of the acoustic receiver array, gaps in coverage were identified. These gaps, combined with the lower accuracy of satellite telemetry, were likely drivers for the larger satellite distributions. Costs differed between telemetry methods, with acoustic telemetry being less expensive at larger sample sizes with a previously established array. Our results suggest that acoustic and satellite telemetry may not provide similar inferences of individual space use. As such, we provide recommendations to identify telemetry methods appropriate for specific study objectives and provide discussion on the biases of each.