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The fall armyworm (FAW), Spodoptera frugiperda Smith (Lepidoptera: Noctuidae), poses a significant threat to food security, necessitating effective management strategies. While chemical control remains a primary approach, understanding the toxicity and detoxification mechanisms of different insecticides is crucial. In this study, we conducted leaf-dipping bioassays to assess the toxicity of quinalphos and beta-cypermethrin·emamectin benzoate (β-cyp·EMB) on S. frugiperda larvae. Additionally, we assessed the response of alterations in CarE, GST, MFO, and AChE activities to sublethal concentrations of these insecticides over various treatment durations. Results indicated that β-cyp·EMB exhibited higher toxicity than quinalphos in S. frugiperda. Interestingly, the highest activities of GST, CarE, MFO, and AChE were observed at 6 h exposure to LC 10 and LC 25 of β-cyp·EMB, surpassing equivalent sublethal concentrations of quinalphos. Subsequently, GST and CarE activities exposure to β-cyp·EMB steadily decreased, while MFO and AChE activities exposure to both insecticides was initially decreased then increased. Conversely, two sublethal concentrations of quinalphos notably enhanced GST activity across all exposure durations, with significantly higher than β-cyp·EMB at 12–48 h. Similarly, CarE activity was also increased at various durations. Our research has exhibited significant alterations in enzyme activities exposure to both concentration and duration. Furthermore, Pearson correlation analysis showed significant correlations among these enzyme activities at different treatment durations. These findings contribute to a better understanding of detoxification mechanisms across different insecticides, providing valuable insights for the rational management of S. frugiperda populations. [Display omitted] • β-cyp·EMB exhibited higher toxicity than quinalphos in S. frugiperda. • Different exposure durations and sublethal concentrations of both insecticides affected activities of CarE, GST, MFO, and AChE. • Significant correlations were observed among CarE, GST, MFO, and AChE activities across different exposure durations. [ABSTRACT FROM AUTHOR]

Background: The ability of cooling period to adjust muscle strength between gender and BMI (Body Mass Index) classification is not well understood, and the use of local cooling as a muscle strength technique is not well acknowledged. Purpose: This study aimed to investigate the effects of local cooling for 30s to 15 min with an ice pack technique on hand grip strength in healthy young adults depending on their gender and BMI classification. Methods: Total participants in this study were 62 active young adults (aged 20.08 ±0.5 years old, BMI of 20.30 ±1.9 kg/m²) to evaluate the effect of an ice pack (10-15°C) on their dominant wrist flexor muscles (1/3 proximal part). Grip strength (kg) was measured with a hand-held dynamometer before cooling as a baseline, at 30s and 15 min after cooling. The variations in grip strength depending on time were evaluated using a one-way repeated measures ANOVA. Results: Grip strength was determined to be slightly lower in females after 30s and 15 min of cooling differentiated to the baseline (p < 0.001); this was not found in males. After cooling, BMI classification revealed association to changes in grip strength; specifically, a significant lowering in grip strength was monitored in the normal-weight category (p < 0.001). Limitations: In this study, subject's skin temperature was not controlled, and the menstrual cycle in female participants was not monitored even though it could have affected the results. Conclusion: Grip strength was significantly correlated with cooling in the female and normal-weight groups. This result suggests that the effects of ice pack cooling on grip strength are dependent on the characteristics of the participants. [ABSTRACT FROM AUTHOR]

A tractor is the main element of agricultural mechanization. However, the use of tractors has some problems, including noise emissions. The exhaust system in tractors is responsible in addition to the transmission of gases released from combustion into the atmosphere, reducing engine noise. In this study, a combined resistance exhaust system was used to reduce noise emission in two common tractors in Iran (285 and 299 Massey-Ferguson tractors). Noise emission was measured and compared in ordinary and combined resistance exhaust systems. The tests of this study were carried out based on international standards for product noise emissions (ISO 7216 and ISO 5131) taking into account the type of the exhaust system, the position of the microphone, engine speed (rpm) and gear position. The number of tests for each tractor reached 72, which consisted of 24 treatments replicated three times. The data obtained were analyzed in the form of a factorial test which was based on a completely randomized design. The results showed that the effect of the main factors of engine speed, gear position, type of exhaust and microphone position on the noise emitted from the tractors was significant at 1% probability level. In all treatments, the combined resistance exhaust system reduced the sound pressure level and increased allowable driver exposure time compared to the ordinary exhaust system. [ABSTRACT FROM AUTHOR]

Oil spilled into an aquatic environment produces oil droplet and dissolved component concentrations and compositions that are highly variable in space and time. Toxic effects on aquatic biota vary with sensitivity of the organism, concentration, composition, environmental conditions, and frequency and duration of exposure to the mixture of oil-derived dissolved compounds. For a range of spill (surface, subsea, blowout) and oil types under different environmental conditions, modeling of oil transport, fate, and organism behavior was used to quantify expected exposures over time for planktonic, motile, and stationary organisms. Different toxicity models were applied to these exposure time histories to characterize the influential roles of composition, concentration, and duration of exposure on aquatic toxicity. Misrepresenting these roles and exposures can affect results by orders of magnitude. Well-characterized laboratory studies for <24-hour exposures are needed to improve toxicity predictions of the typically short-term exposures that characterize spills. • Oil spills produce highly variable water column oil and dissolved concentrations. • Differential weathering and partitioning yields highly variable compositions. • Duration of exposure to aquatic biota is typically on the time scale of hours. • Oil transport, fate and exposure modeling demonstrates dynamic exposures. • Toxicity predictions ignoring dynamics and based on total measured compounds are inaccurate. [ABSTRACT FROM AUTHOR]

Background: Carbon monoxide poisoning (COP) accounts for a large number of emergency department visits worldwide and is fatal in many cases. In surviving patients, neurological sequelae (NS) attributable to cerebral hypoxia are the most devastating outcome, but reliable predictors are limited. Therefore, we conducted a study to identify predictors of NS in patients with COP and evaluate their effects.Methods: In this retrospective case-control study, we identified patients with COP in a medical center in Southern Taiwan between January 2005 and December 2014. Cases were patients with NS, and controls were patients without NS. We obtained information on potential predictors of NS from medical records and evaluated their association with NS, including demographic characteristics, exposure source, suicide attempts, duration of exposure (by tertile), histories, symptoms, signs, laboratory data, treatment, and the length of hospital stay.Results: We included 371 patients with COP. Of them, 93 developed NS, and their mean ages (41.4 ± 14.7 years vs. 39.7 ± 14.2 years) and proportions of males (59.1% vs. 58.6%) were similar to those in the 298 controls. Multivariate logistic regression showed that a history of hypertension (adjusted odds ratio = 2.1; 95% confidence interval = 1.0, 4.5) and a longer duration of carbon monoxide exposure (adjusted odds ratio = 1.7; 95% confidence interval = 1.1, 2.8; the longest tertile [>5 hours] vs. the other two tertiles [≤5 hours]) were independent predictors for NS, but not the level of carboxyhemoglobin.Conclusions: This study identified two independent predictors for NS that may be useful for public healthcare workers and physicians in predicting outcomes and deciding on treatment strategies for COP patients. [ABSTRACT FROM AUTHOR]

This study aims to compare differential effects of continuous and pulsed BaP exposures on metabolism and antioxidant defense in the liver of large yellow croaker. Fish were subjected to BaP for 4 days and 36 days in three exposure regimes with the same time-averaged concentration of BaP: 4 μg/L BaP continuously, 8 μg/L BaP for 24 h every other day or 16 μg/L BaP for 24 h every 4 days. Our results showed that compared to pulsed BaP exposures, continuous BaP exposure reduced BaP metabolism (CYP1A , CYP3A and AHR transcriptional expressions, GSH content, GSH/GSSG ratio, EROD and GST activities) and antioxidant defense (T-SOD activity) on day 4, resulting to the increases in MDA and PC contents, indicating that continuous BaP exposure induced more severe oxidative damage during the early stage of exposure. But continuous BaP exposure reduced MDA and PC contents by improving BaP metabolism and antioxidant defense during the late stage of exposure. CYP1B transcriptional expression and CAT activity were unsuitable biomarkers of both continuous and pulsed BaP exposures. In conclusion, our results demonstrated differential effects of continuous and pulsed exposures on BaP metabolism and antioxidant responses, which were depend on exposure duration. • Continuous and pulsed BaP exposures had differential toxicological effects on fish. • All the BaP exposure treatments induced oxidative damage on day 4. • Continuous BaP exposure alleviated while pulsed BaP exposures aggravated oxidative damage on day 36 compared to those on day 4. • CYP1B mRNA and CAT activity were unsuitable biomarkers for BaP exposure. [ABSTRACT FROM AUTHOR]

Elevated exposure to airborne particulate matter is linked to deleterious health and well-being outcomes. Exposure assessment can be improved through enhanced understanding of source-receptor relationships, for example as expressed in the inhalation intake fraction metric. This study provides new knowledge about how inhalation intake of airborne particles varies with spatially varying indoor emissions. In a controlled environmental chamber with low background particle levels, we monitored the time- and size-resolved particle concentrations at multiple locations including the subject's breathing zone. We investigated two types of particle emissions: (i) controlled releases from several specific indoor locations; and (ii) natural release from skin and clothing for a range of simulated occupant activities. Findings show that particles released proximate to the human envelope caused a total inhalation intake fraction of 7–10 per thousand, which was 1.5–16 × higher than the intake fraction for other indoor release locations. These outcomes reflect the influence of emissions-receptor proximity combined with the efficient transport of particles by means of the thermal plume to the breathing zone. The results show that the well-mixed representation of an indoor environment could underestimate the inhalation intake by 40–90% for various localized indoor emissions, and by up to 3 × for particles emitted from the human envelope. The post-release exposure period contributed substantially to total inhalation intake. For particles released naturally from the human envelope, inhalation intake fractions varied with activity type and were higher for a subject when seated rather than walking. [ABSTRACT FROM AUTHOR]

Agricultural mechanisation is accompanied by several challenges, one of them is the noise pollution caused by machinery. Noise pollution has undesirable effects on humans such as temporary or permanent loss of hearing, decrease in working efficiency and increase in accidents. The aim of this study is to assess noise pollution in the 1055I John Deere combine harvester. The tests were performed at different engine speeds, gear positions and sound measuring locations. The obtained data were analysed in the form of factorial test based on a completely randomised design. An artificial neural network model was created to predict the sound level in the combine. The results of variance analysis for the effects of the main factors on the level of sound were significant at probability level of 1%. The sound intensity reaching the driver's ear based on frequency analysis is equal to 84.16 dB at the frequency of 4000 Hz. The mean square error and the correlation coefficient for the best neural network with ten neurons in the hidden layer were obtained. The permitted time duration of driving the harvester was calculated to be less than 2 h. [ABSTRACT FROM AUTHOR]

Recent studies have shown that short-term exposure to high levels of indoor carbon dioxide (CO 2) could negatively affect human cognitive performance, but the results are still controversial. In this study, a systematic review and meta-analysis of fifteen eligible studies was performed to quantify the effects of short-term CO 2 exposure on cognitive task performance. The control CO 2 levels used for comparison were below 1000 ppm, while the exposure concentrations were divided into three groups: 1000–1500 ppm, 1500–3000 ppm, and 3000–5000 ppm. The results indicated that CO 2 exposure below 5000 ppm impacted human cognitive performance, with complex cognitive tasks being more significantly affected than simple tasks. The complex task performance declined significantly when exposed to additional CO 2 concentrations of 1000–1500 ppm and 1500–3000 ppm, with pooled standardized mean differences (SMDs) (95% CI) of −2.044 (−2.620, −1.467) and −0.860 (−1.380, −0.340), respectively. Moreover, prolonged exposure to CO 2 may exacerbate the adverse effects on complex task performance. School-aged children also exhibited a slight decrease in simple task accuracy when exposed to ventilation-manipulated CO 2 concentrations of 1500–3000 ppm, with a SMD (95% CIs) of −0.117 (−0.225, −0.009). Besides, the complex task performance of the occupational-exposure population was less impaired by increased CO 2 exposure than that of the general population. The meta-analyses provide new evidence to support the recommendation for a stricter occupational exposure concentration limit of less than 1000 ppm in workplaces that require high cognitive demands. Moreover, the exposure duration for performing complex cognitive tasks at high indoor CO 2 concentrations is suggested to be no more than 120 min. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of West Indian Medical Journal is the property of West Indian Medical Journal (WIMJ) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Asymmetric thermal radiation from a cold surface, could easily cause local thermal discomfort and even health problems, such as knee osteoarthritis. An experiment with subjects was conducted to study the radiant asymmetry caused by a cold wall at a room temperature of 18 °C, which is the lower limit of the room temperature for heating design in Chinese Building Regulations. The temperature of a single wall was set at 15 °C and 12 °C respectively to simulate a cold exterior wall or window. A control experiment was also conducted under uniform chamber conditions. Groups of 24 healthy college students participated in the experiments. During the first 30 min of the 90-min experiment, the participants could adjust their clothing to approach thermal comfort. The skin temperatures and thermal perceptions of the subjects were measured. The results indicated that clo-value for participants increased with the decrease of the temperature of the cold wall. The skin temperatures and thermal sensations of the limbs were significantly lower than these of the upper torso. The skin temperature of the calf was the lowest. The prolonged exposure to the cold wall decreased the acceptability of the subjects. Accepting 5% of the subjects expressed local discomfort, the acceptable radiant temperature asymmetry was 4.2 K. The limit value obtained in this experiment was significantly lower than the limit value recommended in the existing standards. The lower acceptable value of radiant temperature asymmetry from this study can provide a relevant input to a revision of existing thermal comfort standards. • An experiment on cold radiant asymmetry caused by a cold wall was conducted. • Subjects adjusted their clothes to keep thermal neutrality during acclimation. • The cold radiant asymmetry increased the non-uniformity of skin temperatures. • Subjects' satisfaction declined with prolonged exposure to cold radiation. • The permissible limit of radiant asymmetry caused by a cold wall was 4.2 K. [ABSTRACT FROM AUTHOR]

Abstract: Nanoparticles (NPs) offer a great possibility for biomedical application, not only to deliver pharmaceutics, but also to be used as novel diagnostic and therapeutic approaches. Currently, there are no data available regarding to what extent the degree of the toxicity and the accumulation of gold nanoparticles (GNPs) are present in in vivo administration. This study aimed to address the GNP size and exposure duration effect on the liver and kidney function of rats: in vivo. Methods: A total of 30 healthy male Wistar-Kyoto rats of the same age (12weeks old) and weighing 220–240g of King Saud University colony were used. Animals were randomly divided into groups, two GNP-treated rat groups and one control group (CG). The 50μl of 10 and 50nm GNPs was intraperitoneally administered in rats for exposure duration of 3days. Then, several biochemical parameters such as aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), alanine transaminase (ALT), alkaline phosphatase (ALP), urea (UREA) and creatinine (CREA) were evaluated. Results: In this study, the AST values increased with the administration of 10 and 50nm GNPs compared with the control. The AST values significantly increased with 10nm GNPs compared with 50nm GNPs and control. The GGT and ALT values decreased with the administration of 10 and 50nm GNPs compared with the control. The GGT and ALT values significantly decreased with 50nm GNPs compared with 10nm GNPs and control. The ALP values significantly decreased with the administration of 10 and 50nm GNPs compared with the control. The decrease in ALP values with 10nm GNPs was higher than those compared with 50nm GNPs. In this study, the levels of UREA and CREA values increased in a non significant manner after the administration of 10 and 50nm GNPs compared with the control. Conclusions: This study demonstrates that the increase in the enzymes AST and the decrease in ALP are smaller GNPs (10nm) size-dependent for exposure duration of 3days; while the decrease in the enzymes GGT and ALT are bigger GNPs (50nm) size-dependent. The levels of UREA and CREA values indicated no significant changes with the administration of 10 and 50nm GNPs for exposure duration of 3days compared with the control. The administration of 10 and 50nm GNPs for short exposure duration of 3days induced only significant variations with some liver enzymes while kidney showed no significant variations. This study suggests that synthesis and metabolism of GNPs as well as the protection of the liver will be more important issues for medical applications of gold-based nanomaterials in future. [Copyright &y& Elsevier]

The article discusses the study of the co-morbidity in mesothelioma that could give an insight into the pathogenesis of the tumor. According to the author, mesothelioma exactly corresponds to the sites of industries with high asbestos use and it develops after a long-time exposure to asbestos. It was also mentioned that the possible co-factors in the pathogenesis of asbestos-related mesothelioma include genetic predisposition, viruses, and recurrent serosal inflammation.

Tropospheric ozone (O 3) affects isoprenoid emissions, and floral emissions in particular, which may result in potential impacts on the interactions of plants with other organisms. The effects of ozone (O 3) on isoprenoid emissions have been investigated for many years, while knowledge on O 3 effects on floral emissions is still scarce and the relevant mechanism has not been clarified so far. We investigated the effects of O 3 on floral and foliar isoprenoid emissions (mainly isoprene, monoterpenes and sesquiterpenes) and their synthase substrates from three rose varieties (CH, Rosa chinensis Jacq. var. chinensis ; SA, R. hybrida 'Saiun'; MO, R. hybrida 'Monica Bellucci') at different exposure durations. Results indicated that the O 3 -induced stimulation after short-term exposure (35 days after the beginning of O 3 exposure) was significant only for sesquiterpene emissions from flowers, while long-term O 3 exposure (90 days after the beginning of O 3 exposure) significantly decreased both foliar and floral monoterpene and sesquiterpene emissions. In addition, the observed decline of emissions under long-term O 3 exposure resulted from the limitation of synthase substrates, and the responses of emissions and substrates varied among varieties, with the greatest variation in the O 3 -sensitive variety. These findings provide important insights on plant isoprenoid emissions and species selection for landscaping, especially in areas with high O 3 concentration. Floral isoprenoid emissions were higher and more sensitive to short-term O 3 exposure relative to foliar emissions, while both foliar and floral emissions significantly decreased after long-term O 3 exposure due to the limitation of their synthase substrates. [ABSTRACT FROM AUTHOR]

Emerging evidence has demonstrated that exposure to fine particulate matter (PM 2.5) is a risk factor for lipid metabolic disorders in the liver. However, the effects of PM 2.5 exposure time duration on hepatic lipid metabolism remain unknown. In this study, C57BL/6 mice were randomly divided into ambient PM 2.5 (PM) or filtered air (FA) exposure chamber for short-term (4 weeks) or long-term (24 weeks) exposure via a whole body exposure system. We measured hepatic triglyceride and free fatty acid levels and analyzed the alteration of lipometabolism-related molecules in the liver. We found that triglyceride levels were significantly elevated in both short-term and long-term PM 2.5 -exposed mice and free fatty acid levels were increased after long-term PM 2.5 exposure. Besides, enzymes for lipolysis and fatty acid oxidation in the liver were inhibited after short-term PM 2.5 exposure but adaptively enhanced after long-term PM 2.5 exposure. Furthermore, molecules for fatty acid uptake were down-regulated in the short-term PM 2.5 -exposed mice whereas molecules for lipid export were induced after long-term PM 2.5 exposure. Therefore, ambient PM 2.5 exposure disturbed hepatic lipid metabolism and the effects varied in different exposure duration. These findings in mice provide new insight into the biological basis of PM 2.5 -induced human metabolic dysfunction and specific strategies may be applied based on different exposure time periods. Image 1 • PM 2.5 exposure induced adaptive enhancement in hepatic lipolysis. • PM 2.5 exposure led to acclimation in fatty acid oxidation in the liver. • Reduced free fatty acid uptake was induced by short-term PM 2.5 exposure. • Elevated lipid export was triggered in response to long-term PM 2.5 exposure. Lipid metabolism and ambient fine particulate matter exposure for different duration. [ABSTRACT FROM AUTHOR]

Extreme high temperatures in summer become more and more universal. However, the effects of high temperature on fitness and performance of different developmental stages in most biological control agents are very limited. The purpose of this work was to evaluate the effects of heat stress and exposure duration on the survival characteristics of immature and adult stages of Propylaea japonica , a dominant aphidophagous ladybeetle in China. Here, we investigated the survival characteristics of different developmental stages in P. japonica when subjecting to high temperatures, 35, 37, 39, 41 and 43 °C for exposure durations of 1, 2, 4 and 6 h, respectively, and 25 °C is the control. The results indicated that egg survival greatly decreased only at 43 °C for 4 h or 6 h, and had no significant difference from 25 to 41 °C for any exposure duration. The younger larvae were the most vulnerable stage with the minimum survival exposure to high temperature but older larvae showed stronger resistance to heat stress. The survivals of pupae and adult stages rapidly decreased only at 43 °C for exceeding 2 h. These results suggest that different developmental stages of P. japonica possess different degrees of heat resistance, which ensures its survival in summer. Moreover, according to the heat resistance of several natural enemy insects in our previous reports and the present results, a comprehensive utilization strategy of aphid biological control was constructed to restrain aphid damage and population growth in challenging environment. • The heat tolerances of different developmental stages of P. japonica were explored. • The egg was the most resistant to heat stress. • The first instar larvae were the most sensitive to heat stress. • The female exhibited more resistant to high temperature stress than male. • The integrated application strategy of aphid biological control was constructed. [ABSTRACT FROM AUTHOR]