Exposure Time Research Articles

Monte Carlo Simulation of Organ Absorbed Dose of Worker's Radiation Exposure in Bone Scintigraphy

Objectives: This study examines individual organ doses and the impact of ionizing radiation sources on effective radiation doses. Methods: In the research, the ICRP-defined adult standing phantom was used as the phantom material in the Visual Monte Carlo Dose Calculation Program (VMC). Subsequently, the incurred doses were calculated by defining different doses, distances, and durations for the 99mTc radioactive source. Results: Exposure times were set at 5 minutes and 20 minutes in comparison. The results indicated that for 5 minutes and 20 minutes at 360 cm, doses remained below the ICRP recommended annual dose limit of 5.7 µSv/h for occupational exposure. Conclusion: Organ absorbed and effective doses varied with exposure time and source-phantom distance. To optimize radiation exposure, people working in radiation fields must make an increased effort to reduce radiation doses following the ALARA principles. Keywords: Effective dose, absorbed dose, VMC software, Monte Carlo

The AstroSat UV Deep Field South. I. Far- and Near-ultraviolet Source Catalog of the GOODS South Region

We present the AstroSat UV Deep Field south (AUDFs), an imaging survey using the wide-field Ultraviolet Imaging Telescope on board AstroSat. AUDFs cover ∼236 arcmin2 of the sky area, including the Great Observatories Origins Deep Survey (GOODS) South field in F154W and N242W filters. The deep and shallow parts of AUDFs have an exposure time ∼62,000 and ∼31,000 s, respectively, in the F154W filter, while in the N242W filter, they are ∼64,000 and ∼34,000 s. These observations reached a 3σ depth of 27.2 and 27.7 AB mag with a 50% completeness limit of 27 and 27.6 AB mag in the F154W and N242W filters, respectively. With the acquired depth, AUDFs is the deepest far- and near-UV imaging data covering the largest area known to date at 1.″2–1.″6 spatial resolution. Two primary catalogs were constructed for the F154W and N242W filters, each containing 13,495 and 19,374 sources brighter than the 3σ detection limit, respectively. Our galaxy counts of a power-law slope of ∼0.43 dex mag−1 in the N242W filter match well with Hubble Space Telescope/Wide-Field Camera 3/UVIS observations. A wide range of extragalactic science can be achieved with this unique data, such as providing a sample of galaxies emitting ionizing photons in the redshift range of z ∼1–3 and beyond, constraining the UV luminosity function, investigating the extended UV emission around star-forming galaxies and UV morphologies for z < 1. The UV catalog will enhance the legacy value of the existing optical/IR imaging and spectroscopic observations from ground- and space-based telescopes on the GOODS South field.

Paleoecology, bioerosion, and paleoenvironments in the Late Miocene of Dar Pahn Unit, Makran, SE Iran

This study focuses on sedimentation patterns and paleoecological conditions during the Upper Miocene in Southeast Iran, specifically analyzing the Rudig section. The sedimentation was predominantly terrigenous and occurred in marine conditions, forming multiple shallowing upwards sequences comprising silty marl, siltstone, and sandstone. The analysis of molluscan shells from this period indicates minimal bioerosion, with encrusters represented solely by Balanus sp. This low level of encrustation suggests rapid sedimentation and brief exposure times. Bioerosion was limited, with Caulostrepsis taeniola borings found only in the shells of vermetid Thylacodes sp. and predatory gastropod Conus sp. Predatory drillings, identified as Oichnus paraboloides were present in the shells of Turritella sp., Corbula sp., and Bursa sp., along with occasional shell aperture peeling repairs in Turritella sp. The presence of abundant large Thalassinoides burrows in the sandstone facies, along with moderate ichnodiversity supports the interpretation of the sandstone facies as shoreface. The rare occurrence of Ophiomorpha nodosa in siltstone facies, and the dominance of burrowing crustaceans in shallow water facies and suspension-feeding mollusks in deeper facies, provides further insight into the paleoenvironment. This study offers a detailed reconstruction of the sedimentary and ecological dynamics during the Upper Miocene in this region, enhancing our understanding of paleoenvironmental conditions and faunal interactions. Keywords: biofacies, sedimentary facies, bioerosion, encrustation, predation, Cenozoic.

Postharvest CO2 treatment and cold storage for Drosophila suzukii (Diptera: Drosophilidae) fruit infestation control.

The invasive pest, spotted wing drosophila (Drosophila suzukii (Matsumura, 1931)or SWD), damages various soft-skinned fruits, severely impacting orchards and vineyards economically. Current sorting practices in commercial production may overlook early-stage SWD infestations, as visible signs take a few days to appear. Our study focused on managing SWD infesting fruits (blueberry, cherry, and raspberry) without visible signs using an artificial atmosphere with elevated CO2 and low temperature. We hypothesized that these factors affect SWD survival and possibly interact, with potential variations among different soft- or stone-fruit species or varieties. High CO2 concentrations and cold storage both negatively affected SWD development. A 24-h 100% CO2 fumigation, without cold storage, significantly reduced SWD infestations in all 3 fruit species studied. On the other hand, 10% CO2 without cold storage did not cause a significant infestation reduction in cherries. Cold storage alone was too slow to be considered effective. Concurrent low-temperature treatment and CO2 treatment reduced the insecticidal efficacy of CO2 fumigation. Optimal fruit sanitation was achieved with a 3-h 100% CO2 treatment at ambient temperature before cold storage. Raspberries were the most suitable host for SWD development, with over a 5-fold higher SWD development compared to blueberries and over 50 times more than in cherries. We discussed the observed interactions between CO2 fumigation and chilling and suggested a simple postharvest SWD management protocol using optimal CO2 levels, exposure times, and chilling periods-achievable without complex equipment.

Factors Influencing the Protective Effect of Salivary Pellicle Against Dental Erosion: A Concise Review

Dental erosion is the irreversible loss of dental hard tissue caused by chemical processes without bacteria involvement. Dental erosion prevalence has increased due to extensive consumption of acidic foods and drinks or suffering from gastrointestinal diseases. Salivary pellicle acts as a physical barrier that impedes direct contact between the tooth surface and erosive acids. Furthermore, it is a selectively permeable membrane that controls the diffusion of erosive acids to the tooth surface. Therefore, salivary pellicle can protect the tooth surface from erosive demineralization. The protective effect of salivary pellicle depends on the intraoral location, tooth substrate, thickness, formation time, composition, the pH level of erosive acids, and exposure time. This concise review aimed to provide an overview on factors influencing the protective effect of salivary pellicle against dental erosion.

Virtual X-ray critical dimension metrology via Monte Carlo simulation.

X-ray critical dimension (XCD) metrology is a highly promising technique for achieving sub-nanometer precision in critical dimension measurements at advanced nodes of integrated circuit manufacturing. Compared to XCD experiments utilizing synchrotron radiation sources, those employing compact X-ray sources encounter challenges like extended testing time and increased uncertainty. To evaluate the influence of experimental conditions on measurement results, we developed an ab initio virtual X-ray critical dimension metrology via a Monte Carlo simulation (MC-VXCD). Through calibrating the system parameters of the MC-VXCD to a home-built compact XCD instrument, we achieved excellent consistency between virtual and actual measurement results. The virtual instrument effectively estimated measurement errors stemming from the reduced exposure time, which significantly influences the measurement accuracy and throughput. Furthermore, through the MC-VXCD, we establish the connection between the application scenarios of the XCD metrology and the geometry of XCD instruments, offering a versatile platform for the system design, experimental configuration optimization, data analysis, etc., in XCD metrology.

Ecotoxicological effects of a glyphosate-based herbicide on Gryllus (Gryllus) assimilis (Orthoptera: Gryllidae) ontogeny: a study on antioxidant system, oxidative stress and cholinergic system.

Brazil is an important global agricultural producer and to increase production the country has extensively used glyphosate-based herbicides (GBH), surpassing consumption and sales records. Consequently, concerns have arisen regarding the potential impact of GBH on ecosystems and non-target organisms. Thus, the effects of GBH exposure were evaluated throughout the cricket Gryllus (Gryllus) assimilis ontogeny, with five developmental stages. Each period contained 3 control and 3 treated boxes, with 15 crickets each, resulting in 90 insects at a time. The control groups received water, while the treated ones were continuously exposed to GBH (0.864 mg.GBH.L-1), with the solutions changed every 48 h. After each exposure time the crickets' group were euthanized to assess the activity of antioxidant enzymes (GST, GR, GPx, and CAT), cholinergic enzymes (ChE), and lipid peroxidation (LPO). The results revealed changes in the systems throughout different developmental phases. Specifically, CAT activity exhibited a significant increase during the nymphal phase, associated with the dismutation of hydrogen peroxide. The GBH increased GST, indicating its role in cellular detoxification, particularly during adulthood. In the senescence stage there was a considerable rise in ChE enzymes, suggesting their involvement in both, choline esters breakdown and potential pesticide detoxification. The action of these enzymes to effectively control lipid peroxidation shows the adaptability of this species to environmental contamination. These findings underscore the long-term effects of agrochemical pollution and emphasize the importance of sustainable practices, effective regulations, and alternative weed control methods.

Measurement of Noise Intensity in the Al-Mahirah Lamdingin Market Area, Banda Aceh City in 2024

Introduction: Noise is a fairly important issue, especially in relation to comfort. Excessive noise levels in markets can have very dangerous negative impacts in many ways, namely health impacts as well as psychological and technical impacts. Objective: The purpose of this study is to identify the noise level that occurs in the market area using a Sound Level Meter (SLM) and to map the noise level in the Al-mahirah Lamdingin market. Methods: This study uses an observation method, data collection is carried out by direct observation and measurement of the research object. The sample in this study is one of the sectors of the community trade center, namely the Al-Mahirah Lamdingin market in Banda Aceh city which consists of 93 kiosks with 639 traders. Inclusion criteria are places where people often gather and pass by, areas that are flanked by lots of noise and come from different sources and machines that operate more than 4 hours in 1 day. Exclusion criteria are locations/areas that do not have noise sources and are far from the main road shoulder, machines that operate for less than 4 hours and operate only at certain times. Data were analyzed using Microsoft Excel software. Results: The results of the study showed that the noise intensity at the Al-Mahirah Lamdingin Market was already in the risky category because it had the highest noise intensity of 55.2 dBA, but did not exceed the threshold value that had been set, namely 65 dBA. Conclusion: Based on the measurement of noise intensity in the Al-Mahirah Lamdingin market, the noise intensity value does not exceed the noise quality standard value but is already at a risky stage because the measurement results are close to the set quality standard and the frequency and time of noise exposure are quite long with the target group. It is necessary to carry out control at each point such as changing the layout of the machine so that the noise does not collect in one place and the use of Hearing Protection Equipment (APT) or it can be by controlling the device, be it equipment renewal or repair.

A rotenone organotypic whole hemisphere slice model of mitochondrial abnormalities in the neonatal brain.

Mitochondrial abnormalities underscore a variety of neurologic injuries and diseases and are well-studied in adult populations. Clinical studies identify critical roles of mitochondria in a wide range of developmental brain injuries, but models that capture mitochondrial abnormalities in systems representative of the neonatal brain environment are lacking. Here, we develop an organotypic whole-hemisphere (OWH) brain slice model of mitochondrial dysfunction in the neonatal brain. We extended the utility of complex I inhibitor rotenone (ROT), canonically used in models of adult neurodegenerative diseases, to inflict mitochondrial damage in OWH slices from term-equivalent rats. We quantified whole-slice health over 6days of exposure for a range of doses represented in ROT literature. We identified 50nM ROT as a suitable exposure level for OWH slices to inflict injury without compromising viability. At the selected exposure level, we confirmed exposure- and time-dependent mitochondrial responses showing differences in mitochondrial fluorescence and nuclear localization using MitoTracker imaging in live OWH slices and dysregulated mitochondrial markers via RT-qPCR screening. We leveraged the regional structures present in OWH slices to quantify cell density and cell death in the cortex and the midbrain regions, observing higher susceptibilities to damage in the midbrain as a function of exposure and culture time. We supplemented these findings with analysis of microglia and mature neurons showing time-, region-, and exposure-dependent differences in microglial responses. We demonstrated changes in tissue microstructure as a function of region, culture time, and exposure level using live-video epifluorescence microscopy of extracellularly diffusing nanoparticle probes in live OWH slices. Our results highlight severity-, time-, and region-dependent responses and establish a complimentary model system of mitochondrial abnormalities for high-throughput or live-tissue experimental needs.

Human-centric lighting asset management for LED bulbs: a context-driven approach on prognostics and maintenance strategy development in public libraries

ABSTRACT Traditional asset management of lighting systems typically focuses on functionality, cost, and lifespan. In contrast, a human-centric approach prioritizes social sustainability and user well-being by ensuring lighting assets “provide the right light at the right time” for diverse activities. Light-emitting diode (LED) bulbs, known for energy efficiency and longevity, have become a preferred choice, yet public libraries often struggle to manage these assets sustainably, remaining in a reactive “fix/replace when it breaks” stage. Current predictive methods, such as artificial intelligence and machine learning, rely on laboratory data that often overlook real-world contexts, leading to performance gaps. This paper presents a context-driven, human-centric methodology for LED prognosis and maintenance strategies in public libraries, employing limited degradation data from LED testing. Advanced analytical techniques, including Markov Chain Monte Carlo (MCMC) and Deviance Information Criterion (DIC), support a shift from function-based to performance-based reliability assessment. By incorporating Mean Time of Exposure (MTOE) and Critical Integrated Levels (CILs), the approach defines optimal maintenance inspection intervals. This research enhances sustainable LED lighting management in public libraries, offering a framework adaptable to broader applications and aligned with human-centric goals..

Effectiveness of the Music Therapy in Dementia: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Studies have not comprehensively examined key variables in music therapy (MT) interventions such as exposure time, session length, and frequency, particularly in relation to patients with dementia. This study investigated the effects of MT on cognitive function, depression, anxiety, behavior, and quality of life in individuals with dementia. Relevant articles published before April 23, 2023, were sourced from five databases, including PubMed, Web of Science, and Embase. Only randomized controlled trials (RCTs) comparing the effects of MT and standard care on the cognitive function, depression levels, anxiety levels, behaviors, and quality of life of individuals with dementia were included. The Reviewers independently extracted data and assessed the studies' methodological quality. Heterogeneity was quantifed using Q statistics from 2 tests and I2 statistics. Outcome analysis was conducted using a random-effects model, and the standardized mean difference (SMD), mean difference, and 95% confidence interval (CI) were calculated. A total of 23 RCTs were included. Compared with the control group, patients who received MT had higher cognitive function, lower levels of depression, and lower levels of anxiety. Meta-regression analysis revealed that the total MT period, total number of MT sessions, weekly MT frequency, MT exposure time, and length of each MT session were associated with an improvement in cognitive function. However, no significant difference was observed in behaviors or quality of life. MT yielded improved cognitive function in individuals with dementia if the intervention spans at least 12 weeks, has at least 16 sessions, and has at least 8 hours of therapy.

Enhancing cyclist safety in cyclist-vehicle interactions through early hazard notifications: a comparison of bi-modal cues at head level

Cyclists frequently face numerous hazards on the road. Often those hazards are posed by motorised vehicles. Advanced support systems that alert cyclists to potential dangers could enhance their safety. However, research in this area, particularly regarding hazard notifications for cyclists, remains sparse. This work assesses bi-modal early hazard notification concepts (combining visual cues with either auditory or tactile feedback) provided at head level (smart glasses with speakers, tactile headband). They are detailing the nature of the hazard, its direction relative to the cyclist, and the timing of exposure. This work investigates cyclists' preference and perception of the proposed concepts for two hazardous situations originating from interactions with vehicles: ‘dooring’, the hazard of a potential collision with an opening door of a parked vehicle (evaluated through a test track study, N = 32) and ‘being overtaken’ which poses the hazard of being cut off or hit by the overtaking vehicle (assessed in a bicycle simulator study, N = 21). The study involved comparisons of supported and unsupported rides, focusing on their impact on usability, intuitiveness, workload, and perceived safety. Our findings reveal varied preferences for the supporting feedback modality, with 56% favouring visual-auditory and 31% visual-tactile. The participants rated user experience, intuitiveness and perceived safety for the use of both concepts quite high. Further, the workload for assisted rides was rated as equally low as for unassisted rides.

Early pregnancy metal levels in maternal blood and pregnancy outcomes.

Prenatal exposure to heavy metals such as Lead (Pb), arsenic (As), cadmium (Cd), and selenium (Se) is associated with various adverse pregnancy outcomes. This study examines the association between early pregnancy maternal blood levels of these metals and adverse pregnancy outcomes, while also addressing the differences between low-risk and high-risk groups based on having a history of preterm birth (PTB). This prospective cohort study recruited parous women during first trimester, categorized into low-risk and high-risk groups. Participants completed a questionnaire, and heavy metal levels were measured in blood samples. Pregnancy outcomes including PTB, low birth weight (LBW), gestational age at delivery, birth weight and head circumference were recorded following delivery. Multivariable analyses were conducted to evaluate the independent associations between heavy metal levels and pregnancy outcomes, while adjusting for maternal age, BMI, employment, smoking, fertility treatments and education. Among 404 participants, the mean (± SD) levels were Pb: 3.12 ± 1.82µg/L, As: 0.41 ± 0.4µg/L, Cd: 0.26 ± 0.34µg/L, and Se: 119.84 ± 21.05µg/L. Significant differences in Pb, Se, Cd and As levels were observed between the low-risk and high-risk groups, with higher levels in the low-risk group. However, no significant associations were found between heavy metal levels and any of the study outcomes in either univariable comparison or multivariable models. These findings highlight the need for further research to understand the potential impact of these metals on pregnancy, considering population-specific factors and exposure timing.

Screen Exposure in 4-Year-Old Children: Association with Development, Daily Habits, and Ultra-Processed Food Consumption

This study aimed to investigate the association between child development, daily habits, and ultra-processed food consumption with screen exposure in 4-year-old children. A cross-sectional study was conducted using a questionnaire that included sociodemographic data, the child’s daily habits, and screenings for child development and eating habits. The daily screen exposure time (cell phone, computer, television, and/or tablet) was measured in minutes and classified as inadequate if &gt;60 min. We conducted bivariate analyses and a generalized linear model. Overall, 362 caregivers–children pairs were investigated. The average screen time per child was 120 min (IQR: 120), and most of the children (71%) showed inadequate screen time for the age group. The longest screen time was associated with the lowest score in child development (β = −0.03; p = 0.01), an increased habit of eating in front of screens (β = 0.34; p &lt; 0.001), and the highest score of ultra-processed foods (UPFs) (β = 0.05; p = 0.001). The sample showed a high prevalence of inadequate screen time, and this has been associated with the lowest score in child development, an increased habit of eating in front of screens, and the highest score of UPFs.

Effect of Mexel®432 on DNA Damage in Haliotis Discus Hannai and Mesocentrotus Nudus

Mexel®432 is a surfactant-like substance that is a biosuppressant against marine fouling organisms. Therefore, to study the toxic effect of Mexel®432 on marine organisms, the wrinkled abalone and echinococcus was exposed to concentrations of 0.175 mg·L-1, 0.350 mg·L-1, 0.700 mg·L-1, 0.275 mg·L-1, 0.550 mg∙L−1, 1.100 mg·L-1 Mexel®432 solution, and single-cell gel electrophoresis (comet experiment) was used to detect different exposure times (0, 10, 20 d) DNA damage effect of digestive gland cells and echinococcus pallidae intestinal cells in wrinkled disc abalone, and tail DNA content, tail length, tail distance, and Olive tail distance were used as evaluation indexes. The results showed that different concentrations of Mexel®432 could cause DNA disintegration and tailing in digestive gland cells and intestinal cells in a short period of time (10 d), and with the increase of Mexel®432 concentration and the extension of exposure time, DNA deformation was obvious, the fragmentation increased, and the degree of damage was aggravated. When the concentration of Mexel®432 reaches 0.350 mg·L-1, it produces certain genotoxicity to the digestive gland cells of wrinkled abalone, and when the concentration of Mexel®432 reaches 1.1000 mg·L-1, it also has certain genotoxicity to the intestinal cells of Mesocentrotus nudus. The experimental results showed that Mexel®432 had a significant dose effect relationship on DNA damage in the cells of two biological tissues.

Impact of Body Mass Index on the Outcomes of Cryoballoon Pulmonary Vein Isolation for Paroxysmal Atrial Fibrillation

Background: Atrial fibrillation (AF) is prevalent among obese patients, and cryoballoon ablation (CBA) is an effective strategy for the rhythm control of AF. The impact of body mass index (BMI) on the clinical outcomes of CBA for AF is not fully explored. Methods: 85 consecutive patients with paroxysmal AF were enrolled and were categorized into three groups as per their BMI: normal weight (BMI 18.5–25 kg/m2), overweight (BMI 25–30 kg/m2), and obese patients (BMI &gt; 30 kg/m2). The primary study endpoint was a late (12 month) recurrence of AF. Early recurrence of AF, symptom improvement, and procedural outcomes were some key secondary outcomes. Results: 20 patients had normal weight, 35 were overweight, and 30 were obese. Obese patients featured a higher prevalence of diabetes mellitus, heavier exposure to smoking, and worse baseline symptoms (as assessed through EHRA class at admission and 12 months before CBA) compared to overweight and normal weight patients. Both late and early (&lt;3 months) AF recurrence rates were comparable across the three groups. Of note, obese patients showed greater improvement in their symptoms post-CBA, defined as improvement by at least one EHRA class, compared to normal weight patients; this might be explained by improved diastolic function. Total procedure time and dose area product were significantly increased in obese patients. The multivariate logistic regression analysis indicated that early AF recurrence and the duration of hypertension are independent predictors of late AF recurrence. Conclusion: CBA is effective in overweight and obese patients with paroxysmal AF. Procedure time and radiation exposure are increased in obese patients undergoing CBA.

Apoptotic Impact of Heliox Cold Plasma on a Cervical Cell Line Using Gold Nanoparticle-Doped Graphene Oxide Nanosheets

Background: Invasive cervical cancer is recognized as the second most common malignancy in women after breast cancer. Objectives: This study investigates, for the first time, the effect of gold nanoparticle-doped graphene oxide (GO) nanosheets on the human epithelial carcinoma (HeLa) cell line in the presence of heliox cold plasma. Methods: Graphene oxide nanosheets were synthesized using the Hummer method and then doped with gold nanoparticles. The nanoparticles were characterized by transmission electron microscopy (TEM), and the diffraction peaks of GO and gold nanoparticles were confirmed through X-ray diffraction (XRD) analysis. Additionally, the optical absorbance of the nanoparticles was measured in the range of 200 - 900 nm using UV-Visible spectroscopy. A plasma generator was fabricated to produce cold plasma using helium (He) and oxygen (O₂) gases at a 99:1 ratio. The radicals generated by the cold plasma were analyzed via optical emission spectroscopy (OES). Cell treatment was conducted by applying various concentrations of GO and GO/Au nanoparticles. Cellular phenotype was monitored through optical microscopy, and biocompatible concentrations of both nanoparticles were determined using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay. Subsequently, cold plasma at varying distances and durations was applied to the nanoparticle-treated cells. The generated radicals and the expression of apoptotic genes in treated cells were assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and real-time PCR, respectively. Results: The width of the bacillus-like gold nanoparticles was 15.13 ± 0.96 nm. The cold plasma generated radicals such as N2I2⁺, N2II1⁻, He•, and O⁻•. XRD analysis confirmed the successful coupling of gold onto the GO nanosheets. The biocompatible concentrations of GO and GO/Au nanoparticles were found to be 30 µg/100 µL and 20 µg/100 µL, respectively, as determined by the MTT assay. Radical formation increased as incubation time was extended from 30 to 60 seconds. Furthermore, real-time PCR analysis demonstrated the highest levels of p53, Bax, and caspase 3/8 expression at a plasma exposure time of 60 seconds in the composite-treated group, while Bcl2 expression was significantly reduced. Conclusions: The findings suggest that the parameters of heliox cold plasma and the concentrations of GO/Au nanoparticles must be optimized to effectively induce apoptosis in cervical cancer cells.

Delivery Methods of Radiopharmaceuticals: Exploring Global Strategies to Minimize Occupational Radiation Exposure.

In the world of nuclear medicine, health care professionals face the challenge of safeguarding themselves and their patients from occupational radiation exposure. As the field experiences exponential growth, driven by the surge in approvals of radiopharmaceuticals for diagnostic and therapeutic applications, it becomes vital to delve into the delivery methods of radiopharmaceuticals. Health care professionals take precautions during radiopharmaceutical administration, including maintaining distance from radioactive sources, using shielding, limiting exposure time, and monitoring radiation levels with badges. Regular evaluations provide compliance with recommended exposure limits, yet concerns persist, especially regarding the cumulative radiation exposure from manual injections over time. Understanding the long-term effects of radiation exposure has spurred the development of cutting-edge medical device technologies, such as autoinjectors, designed to administer radiopharmaceuticals accurately while minimizing total radiation dose to health care professionals. The U.S. Pharmacopeia 825 regulation refers to these devices as "direct infusion systems." Nuclear medicine technologists commonly refer to them as "autoinjectors," whereas device manufacturers may use terms such as injection system, radiopharmaceutical injector, or infusion system. Despite variations in terminology, these devices hold a pivotal role in shaping the future of radiopharmaceutical delivery. In an era of escalating demand for PET procedures worldwide, skilled health care professionals ensure the safe and precise dosing of radiopharmaceuticals. This article explores the state-of-the-art medical devices in radiopharmaceutical delivery, spotlighting transformative medical devices currently revolutionizing the nuclear medicine landscape in the global market.

Analyzing the occupational exposure risks of dental healthcare workers from the perspective of repeated occupational exposure.

Healthcare workers in dental hospitals frequently experience repeated occupational exposures (ROEs). In our study, we aim to analyze these repeated exposures among dental healthcare workers (DHWs), assess the risk levels of different risk factors, and explore the significance of ROE data for infection control in dental hospitals. Based on hospital statistical data, we categorized the occupational exposure incidents at West China Hospital of Stomatology over the past seven years into initial and repeated exposures. We analyzed the association of various risk factors, including personnel types, gender, treatment locations, timing of occupational exposure, and pathways of occupational exposure, with the occurrence of repeated exposures. The Statistical Package for Social Sciences (SPSS) 21 was used to conduct chi-square analysis and binary logistic regression analysis, with the significance level set at p < 0.05. Compared to students, hospital dentists with teaching qualifications exhibited a higher risk of ROEs. The risk of repeated exposure for dental students was 60% lower than that of hospital dentists (P = 0.003). However, gender, treatment locations, timing of occupational exposure, and pathways of occupational exposure did not significantly impact the repeated exposures among DHWs. Our study demonstrates that the analysis of repeated occupational exposures (ROEs) is meaningful. In our study, hospital dentists with teaching qualifications had the highest risk of ROEs, compared to dental students, hospital dental nurses, and dental nurse students. This means that among individuals who have already experienced occupational exposure, hospital dentists are more likely to experience repeated exposure. Meanwhile, gender, treatment locations, timing of occupational exposure, and pathways of occupational exposure did not have a significant impact on the occurrence of ROEs.

Older Amphibian Larvae Are More Sensitive to Ultraviolet Radiation and Experience More Sublethal Carryover Effects Post-Metamorphosis.

Elevated ultraviolet radiation (UVR) is postulated as one of multiple, interrelated environmental stressors driving amphibian population declines globally. However, key knowledge gaps remain in elucidating the link between elevated UVR and amphibian declines in a changing climate, including whether timing and irradiance of UVR exposure in early life dictates the onset of detrimental carryover effects post-metamorphosis. In this study, striped marsh frog larvae (Limnodynastes peronii) were exposed to UVR at one of two different irradiances for up to 7 days, either as hatchlings (Gosner stage 23) or as older larvae (Gosner stage 25-28). These animals were then reared to metamorphosis in the absence of UVR to examine independent and interactive carryover effects throughout development. Older larvae were more sensitive to UVR than hatchlings, with 53.1% and 15.6% mortality in larvae exposed to high and low irradiance respectively, compared with no mortality of hatchlings in either irradiance treatment. Irradiance and timing of UVR exposure had interactive effects on larval body length, causing stunted growth patterns and a lack of compensatory growth following UVR exposure, particularly in animals exposed to high irradiance UVR later in development. Timing of UVR exposure also determined the severity of carryover effects into metamorphosis, including delayed metamorphosis and the first published account (to our knowledge) of latent UVR-induced depigmentation in an amphibian. These findings highlight how acute changes to the larval UVR exposure regime can impact on amphibian health later in life, with implications for our understanding of the effects of climate change on UVR-related amphibian declines.