Search

This study considers a deliberate hypothetical release of radioactive material over an inhabited urban zone. The event is initiated by the activation of a radiological dispersion device. The main threat is the deposition of radioactive material onto the soil's surface. The radiation represents the threat-defining risks, which depend on the main variables, i.e. soil surface roughness, sex, age of the exposed individuals and the moment of the release (day or nighttime). This study aims to evaluate the effect of soil surface roughness on the radiological risk. The simulation was performed by an analytical method using the HotSpot Health Physics code within the first 100 h. The results found relevant elements that allow for differentiating consequences as a function of the time of release (whether daytime or nighttime), thus allowing decision-makers to be supported with a little more detail about the situation, although in a critical initial phase., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: During invasive procedures involving needles, there is a chance of damage to peripheral nerves. Therefore, a method for experimentally simulating these situations is needed., Objectives: In this study we aimed to evaluate peripheral nerve lesions caused by the entry and exit of an injection needle, nerve transfixion through a suture stitch, and the injection of saline solution and lidocaine into the nerve., Methods: After obtaining approval from the Animal Ethics Committee, we randomly divided 36 Wistar rats, weighing approximately 250 g each, into 6 groups (control, sham, suture, needle, saline, and lidocaine groups), with 6 animals in each group. All procedures were performed on the left paws of the rats. After the procedure, walking track analysis was performed to assess the walking function of rats for 8 weeks. Four months after the procedures, we performed bilateral electrophysiological studies (measuring the latency and amplitude of the electrical impulse in the peroneal nerve). Subsequently, the rats were euthanized, and bilateral tissue samples were collected from the peroneal nerve and tibialis cranialis muscle for morphometric histological analysis., Results: In the walking track analysis, all groups showed normalization of walking functionality after 13 days. There was little histological change between the groups, and no functional loss related to the procedures was observed., Conclusions: Procedures involving the infusion of local anesthetic or saline solution, or suture needles, are safe with regard to peripheral nerve function loss. Accidents tend not to cause nerve impairment., (© The Author(s) 2023. Published by Oxford University Press on behalf of The Aesthetic Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The development of the human nervous system makes up a series of fundamental and interdependent events involving birth, growth, and neuronal maturation, in addition to the positive or negative selection of synapses of these neurons that will participate in the composition of neural circuits essential to the activity of the nervous system. In this context, where environment and social relationships seem to be relevant markers for neurodevelopment, advanced neuroimaging techniques and behavioral assessment tools have demonstrated alterations in brain regions and cognitive functions among children developing in low or high socioeconomic status environments. Considering the aspects mentioned, this review aimed to identify the importance of socioeconomic status in children's brain development, seeking to identify what are the impacts of these factors on the morphological and physiological formation of the nervous system, allowing a greater understanding of the importance of environmental factors in neurodevelopmental processes., Competing Interests: Disclosure: The authors report no conflicts of interest.

This systematic review aimed to analyze the development and functionality of microfluidic concentration gradient generators (CGGs) for toxicological evaluation of different biological organisms. We searched articles using the keywords: concentration gradient generator, toxicity, and microfluidic device. Only 33 of the 352 articles found were included and examined regarding the fabrication of the microdevices, the characteristics of the CGG, the biological model, and the desired results. The main fabrication method was soft lithography, using polydimethylsiloxane (PDMS) material (91%) and SU-8 as the mold (58.3%). New technologies were applied to minimize shear and bubble problems, reduce costs, and accelerate prototyping. The Christmas tree CGG design and its variations were the most reported in the studies, as well as the convective method of generation (61%). Biological models included bacteria and nematodes for antibiotic screening, microalgae for pollutant toxicity, tumor and normal cells for, primarily, chemotherapy screening, and Zebrafish embryos for drug and metal developmental toxicity. The toxic effects of each concentration generated were evaluated mostly with imaging and microscopy techniques. This study showed an advantage of CGGs over other techniques and their applicability for several biological models. Even with soft lithography, PDMS, and Christmas tree being more popular in their respective categories, current studies aim to apply new technologies and intricate architectures to improve testing effectiveness and reduce common microfluidics problems, allowing for high applicability of toxicity tests in different medical and environmental models.

Considering there are several difficulties and limitations in labeling stem cells using multifunctional nanoparticles (MFNP), the purpose of this study was to determine the optimal conditions for labeling human bone marrow mesenchymal stem cells (hBM-MSC), aiming to monitor these cells in vivo. Thus, this study provides information on hBM-MSC direct labeling using multimodal nanoparticles in terms of concentration, magnetic field, and period of incubation while maintaining these cells' viability and the homing ability for in vivo experiments. The cell labeling process was assessed using 10, 30, and 50 µg Fe/mL of MFNP, with periods of incubation ranging from 4 to 24 h, with or without a magnetic field, using optical microscopy, near-infrared fluorescence (NIRF), and inductively coupled plasma mass spectrometry (ICP-MS). After the determination of optimal labeling conditions, these cells were applied in vivo 24 h after stroke induction, intending to evaluate cell homing and improve NIRF signal detection. In the presence of a magnetic field and utilizing the maximal concentration of MFNP during cell labeling, the iron load assessed by NIRF and ICP-MS was four times higher than what was achieved before. In addition, considering cell viability higher than 98%, the recommended incubation time was 9 h, which corresponded to a 25.4 p g Fe/cell iron load (86% of the iron load internalized in 24 h). The optimization of cellular labeling for application in the in vivo study promoted an increase in the NIRF signal by 215% at 1 h and 201% at 7 h due to the use of a magnetized field during the cellular labeling process. In the case of BLI, the signal does not depend on cell labeling showing no significant differences between unlabeled or labeled cells (with or without a magnetic field). Therefore, the in vitro cellular optimized labeling process using magnetic fields resulted in a shorter period of incubation with efficient iron load internalization using higher MFNP concentration (50 μgFe/mL), leading to significant improvement in cell detection by NIRF technique without compromising cellular viability in the stroke model.

Statistics plays a key role in many areas of modern society, including technology, social and behavior studies, economics, and the sciences. Statistics anxiety (SA) has a detrimental impact on academic experiences in university populations, although the mediating factors remain underexplored. We conducted the first systematic review and meta-analysis focused on SA in university students in the context of statistical performance, individual differences in statistical learning, self-perceptions regarding the statistics course and instructor, and sociodemographic factors. Searches were carried out in the PsycINFO, PubMed, Scielo, and Web of Science databases according to our preregistration. Forty studies were selected for systematic review. Seventeen were included in a series of six meta-analyses concerning academic achievement, attitudes, self-perception, procrastination, and gender. The findings reveal learning strategies, procrastination, self-efficacy, and self-awareness as predictors of SA. However, the impact of sociodemographic data in these moderators is still uncharted. We conclude with a critical appraisal of the selected studies and present future directions for research in SA., (© 2022 New York Academy of Sciences.)