Increase In Duration Of Exposure Research Articles

Exploring changes in microplastic-associated bacterial communities with time, location, and polymer type in Liusha Bay, China

Microplastics have become a widespread concern within marine environments and are particularly evident in aquaculture regions that are characterized by plastic accumulation. This study employed 16 S rDNA sequencing to investigate the dynamic succession of microbial communities colonizing polyvinyl chloride (PVC), polystyrene (PS), and polyamide (PA) microplastics in seawater, when subjected to varying exposure durations in the Liusha Bay aquaculture region. Results revealed that the composition of microplastics microbial communities varied remarkably across geographical locations and exposure times. With an increase in exposure duration, both the diversity and richness of bacterial communities colonizing microplastics significantly increased, microbial communities show adaptations to the plastisphere. The type of microplastics had a significant effect on the community structure characteristicsof bacteria attached to their surfaces, with inconsistent trends in the relative abundance of different genera on different substrates. Notably, microplastic surfaces harbored a significant abundance of hydrocarbon-degrading bacteria, exemplified by Erythrobacter. These findings underscore the potential of microplastics as unique microbial niches. Meanwhile, long-term exposure experiments also offer the possibility of screening for plastic-degrading bacteria. In addition, the presence of the pathogenic bacterium Vibrio was detected in all microplastic samples, implying that microplastics could serve as carriers for pathogenic dissemination. This underscores the urgency of addressing the risk posed by the proliferation of harmful bacteria on microplastic surfaces. Overall, this study enhances our understanding of microbial community dynamics on microplastics under diverse conditions. It contributes to the broader comprehension of plastisphere microbial ecosystems in the marine environment, thereby addressing critical environmental implications.

Effects of Thermal Exposure on the Microstructure and Mechanical Properties of a Ti-48Al-3Nb-1.5Ta Alloy via Powder Hot Isostatic Pressing.

Research on how thermal exposure affects the microstructure and mechanical properties of the Ti-48Al-3Nb-1.5Ta (at. %) alloy, which is prepared via powder hot isostatic pressing (P-HIP), is essential since this low-density alloy shows promise for use in high-temperature applications, particularly for aero-engines, which require long-term stable service. In this study, a P-HIP Ti-48Al-3Nb-1.5Ta (at. %) alloy was exposed to high temperatures for long durations. The phase, microstructure and mechanical properties of the P-HIP Ti-48Al-3Nb-1.5Ta alloy after thermal exposure under different conditions were analyzed using XRD, SEM, EBSD, EPMA, TEM, nanomechanical testing and tensile testing. The surface scale is composed of oxides and nitrides, primarily Al2O3, TiO2, and TiN, among which Al2O3 is preferentially generated and then covered by rapidly growing TiO2 as the thermal exposure duration increases. The nitrides appear later than the oxides and exist between the oxides and the substrate. With increasing exposure temperature and duration, the surface scale becomes more continuous, TiO2 particles grow larger, and the oxide layer thickens or even falls off. The addition of Ta and Nb can improve the oxidation resistance because Ta5+ and Nb5+ replace Ti4+ in the rutile lattice and weaken O diffusion. Compared with the P-HIP Ti-48Al-3Nb-1.5Ta alloy, after thermal exposure, the grain size does not increase significantly, and the γ phase increases slightly (by less than 3%) with the decomposition of the α2 phase. With increasing thermal exposure duration, the γ phase exhibits discontinuous coarsening (DC). Compared with the P-HIP Ti-48Al-3Nb-1.5Ta alloy, the hardness increases by about 2 GPa, the tensile strength increases by more than 50 MPa, and the fracture strain decreases by about 0.1% after thermal exposure. When the depth extends from the edge of the thermally exposed specimens, the hardness decreases overall.

Investigation of critical factors influencing the underestimation of hearing loss predicted by the ISO 1999 predicting model.

To analyze factors influencing the underestimation of noise-induced permanent threshold shift (NIPTS) among manufacturing workers, providing baseline data for revising noise exposure standard. A cross-sectional study was designed with 2702 noise-exposed workers from 35 enterprises from 10 industries. Personal noise exposure level(LAeq,8h) and noise kurtosis level were determined by a noise dosimeter. Questionnaires and hearing loss tests were performed for each subject. The predicted NIPTS was calculated using the ISO 1999:2013 model for each participant, and the actual measured NIPTS was corrected for age and sex. The factors influencing the underestimation of NIPTS were investigated. The predicted NIPTS at each test frequency (0.5, 1, 2, 3, 4, or 6kHz) and mean NIPTS at 2, 3, 4, and 6kHz (NIPTS2346) using the ISO 1999:2013 model were significantly lower than their corresponding measured NIPTS, respectively (P < 0.001). The ISO model significantly underestimated the NIPTS2346 by 12.36 dB HL. The multiple linear regression analysis showed that noise exposure level, exposure duration, age, and kurtosis could affect the degree of underestimation of NIPTS2346. The generalized additive model (GAM) with (penalized) spline components showed nonlinear relationships between critical factors (age, exposure duration, noise level, and kurtosis) and the underestimated NIPTS2346.The underestimated NIPTS2346 decreased with an increase in exposure duration (especially over ten years). There was no apparent trend in the underestimated NIPTS2346 with age. The underestimated NIPTS2346 decreased with the increased noise level [especially > 90 dB(A)]. The underestimated NIPTS2346 increased with an increase in noise kurtosis after adjusting for the noise exposure level and exposure duration and ultimately exhibiting a linear regression relationship. The ISO 1999 predicting model significantly underestimated the noise-induced hearing loss among manufacturing workers. The degree of underestimation became more significant at the noise exposure condition of fewer than ten years, less than 90 dB(A), and higher kurtosis levels. It is necessary to apply kurtosis to adjust the underestimation of hearing loss and consider the applying condition of noise energy metrics when using the ISO predicting model.

21 Toxic Wounds are Associated with Cognitive Decrements in Women Veterans of the 1991 Gulf War

Objective:Gulf War Illness (GWI) is a debilitating multi-symptom condition that affects nearly a third of 1990-91 Gulf War (GW) veterans. Symptoms include chronic pain, debilitating fatigue, gastrointestinal issues, and cognitive decrements. Prior studies have documented reduced cognitive functioning in this affected population, particularly in the areas of memory, attention and response inhibition. To date, research has focused on cognitive functioning in male and female veterans together. Very limited research has reported on GW women's cognitive functioning separately mostly due to scarcity of data on women veterans. In this study, we had the unique opportunity to utilize a newly combined neuropsychological test dataset from women GW veterans in the Boston, Biorepository and Integrative Network (BBRAIN) for GWI. The aim was to compare neuropsychological outcomes with toxicant exposures in women veterans with and without GWI.Participants and Methods:Cognitive data from the BBRAIN biorepository was used for this study. The sample consisted of 62 women veterans who were deployed to the Persian Gulf War from 1990-91. Neuropsychological test scores included the Conners Continuous Performance Test Third Edition (CPT3), Delis-Kaplan Executive Function System (D-KEFS) Color-Word Interference, and the California Verbal Learning Test Second Edition (CVLT-II). War-related exposure to chemical weapons, anti-nerve gas pills and pesticides were measured by a self-reported survey. For analysis, war-related exposure was classified into three groups: controls with 0-6 days of exposure; cases with 0-6 days of exposure and cases with 7 or more days of exposure. Multiple linear regression modeling was used to measure differences in neuropsychological scores across the three groups by each war-related exposure.Results:After adjusting for age, education and other exposures, an increase in duration of exposure to pesticides was significantly associated with worse CPT3 commission errors, fewer words correct in the CVLT-II trials 1-5, and an increase in self-corrected errors on DKEFS Color-Word Interference Test Trials 1, 2 and 4 (p&lt;0.05). More days reported hearing chemical alarms and seeing smoke from oil well fires was significantly associated with fewer words correct on all CVLT-II trials, and more self-corrected errors on Color-Word Interference Trials 2 and 4 (p&lt;0.05). An increase in exposure duration to pyridostigmine bromide anti-nerve gas pills was associated with fewer words correct on the CVLT-II learning Trials 1-5 and short delay recall and an increase in self-corrected errors on Color-Word Interference Trials 2, 3, and 4 (p&lt;0.05). When associations were adjusted for PTSD, all significant associations stayed constant (p&lt;0.05).Conclusions:In this study, women veterans with GWI who had higher levels of exposure to pesticides, oil well fires and who took more antinerve gas pills during the war are showing increased learning difficulties and more deficits in attention and response inhibition. Future research should examine if similar patterns of neuropsychological symptoms are also present in male GW veterans with higher war-time related toxicant exposures.

Progressive collapse resistance of RC frames subjected to localized fire

Fire is one of the accidental loads that can cause progressive collapse of buildings. However, the behavior of fire-exposed reinforced concrete (RC) frames to resist progressive collapse are still unclear. Therefore, a numerical study on the RC assembly based on the sequential thermal-mechanical coupling method is conducted. Fire effects on the failure mode, load-resistant capacity, and the evolution of load-resistant mechanisms of the RC frame are captured. The numerical results show that compressive arch action (CAA) and catenary action (CA) can develop in sequence for the specimens exposed to fire within a short fire duration of 30 min. The failure of the specimen is controlled by the fracture of beam rebars near the removed column. However, when the fire duration exceeds 60 min, the specimen is difficult to develop effective CA due to a decrease of over 80% in the tensile strength of the bottom reinforcement. The failure of the specimen is dominated by the fracture of the rebar at the cut-off point of the beam top rebar. Fire lasting for 30 min, 60 min, 90 min and 120 min results in a decrease of 41%, 72%, 77% and 78% in ultimate load, respectively. Increasing the span-depth ratio can upgrade the deformation capacity of the specimen, but it is adverse to the development of CAA. The effects of the reinforcement ratio on the failure mode, the ultimate load and deformation capacity are mild as the fire exposure duration increases.

The role of kurtosis and kurtosis-adjusted energy metric in occupational noise-induced hearing loss among metal manufacturing workers.

Noise energy has been well-established to increase the risk of occupational noise-induced hearing loss (NIHL). However, the role of noise temporal structure (expressed by kurtosis) or its combination with energy metrics (e.g., kurtosis-adjusted cumulative noise exposure, adj-CNE) in occupational NIHL was still unclear. A cross-sectional survey of 867 Chinese workers, including 678 metal manufacturing workers and 189 workers exposed to Gaussian noise, was conducted. Noise energy metrics, including LAeq,8h and CNE, kurtosis (β), and adj-CNE were used to quantify noise exposure levels. Noise-induced permanent threshold shift at frequencies 3, 4, and 6 kHz (NIPTS346) and the prevalence of high-frequency NIHL (HFNIHL%) were calculated for each participant. The dose-response relationship between kurtosis or adj-CNE and occupational NIHL was observed. Among 867 workers, different types of work had specific and independent noise energy and kurtosis values (p > 0.05). HFNIHL% increased with an increase in exposure duration (ED), LAeq,8h, CNE, or kurtosis (p < 0.01), and there were strong linear relationships between HFNIHL% and ED (coefficient of determination [R2] = 0.963), CNE (R2 = 0.976), or kurtosis (R2 = 0.938, when CNE < 100 dB(A)∙year). The "V" shape notching extent in NIPTS became deeper with increasing kurtosis when CNE < 100 dB(A)∙year and reached the notching bottom at the frequency of 4 or 6 kHz. The workers exposed to complex noise (β ≥ 10) had a higher risk of NIHL than those exposed to Gaussian noise (β < 10) at the frequencies of 3, 4, 6, and 8 kHz (OR > 2, p < 0.01). Moreover, HFNIHL% increased with adj-CNE (p < 0.001). There were strong linear relationships between NIHL and adj-CNE or CNE when β ≥ 10 (R2adj-CNE > R2CNE). After CNE was adjusted by kurtosis, average differences in NIPTS346 or HFNIHL% between the complex and Gaussian noise group were significantly reduced (p < 0.05). Kurtosis was a key factor influencing occupational NIHL among metal manufacturing workers, and its combination with energy metrics could assess the risk of NIHL more effectively than CNE alone.

TOXICOLOGICAL EFFECTS OF TERTIARY MIXTURE OF METALS ON THE OXIDATIVE STRESS IN CIRRHINA MRIGALA AND LABEO ROHITA

Present research work was conducted to measure the effects of tertiary metals mixture (Fe+Zn+Mn) on superoxide dismutase (SOD) activity in various tissues of two major carps, Cirrhina mrigala and Labeo rohita at controlled laboratory conditions. 90-day-old fingerlings of both fish species were exposed to 1/4th and 1/5th of their respective 96-hr LC50 value of Fe+Zn+Mn mixture, for 24 days. After 6, 12, 18, and 24-day exposure, fish from each treatment will be sampled, dissected and their tissues viz. brain, gills, kidney, and heart isolated for the SOD enzyme assay. The physical and chemical parameters of test media viz. pH, temperature, dissolved oxygen, total hardness, carbon dioxide, total ammonia, magnesium, and calcium were determined on a 12-hourly basis. It was observed that with an increase in metal concentration, the activity of enzymes increased significantly in both fish species which was maximum at 1/4th of LC50 with the mean value of 49.35±10.04 UmL-1 in C. mrigala. In Labeo rohita, SOD activity decreased with an increase in exposure duration. SOD activity was maximum on day 6 at 52.22±12.91 UmL-1, and on day 24, it was minimum at 35.01±6.91 UmL-1. Among the organs, the SOD activity followed the trend: gills &gt; heart &gt; kidney &gt; brain. The various tissues of metals mixture treated fish Cirrhina mrigala showed significantly increased activity of SOD in comparison to Labeo rohita. All the physicochemical parameters varied significantly at p&lt;0.05 during this study period.

Beta-cyfluthrin-Induced Alterations in the Total and Differential Haemocytes Count in the Red Cotton Bug, Dysdercus koenigii (Fabricius,1775)

Dysdercus koenigii is a major global pest of cotton that causes severe economic loss. Among several control measures, pyrethroids are frequently used toxicants because of high efficacy at low dosages and relative safety. Since haemocytes are biomarkers of the physiological response and immunity of insect which determine the insecticide efficacy, the current study assessed the effect of a pyrethroid, β-cyfluthrin, on the total and differential haemocyte counts of D. koenigii. Haemolymph was collected from the fifth instars after the topical application of β-cyfluthrin (0.8, 1.6, 3.2, 6.4 and 12.8 mg/L) on the thoracic tergum. The haemolymph of control nymphs revealed 5270 haemocytes/mm3 which decreased instantly by 1.4-3.1-fold on β-cyfluthrin exposure; more reduction observed at lower dosages. Increase in exposure duration and β-cyfluthrin dosages fluctuated the count considerably, eventually raising them at lower dosages and diminishing at higher dosages. Among five kinds of haemocytes recorded in the haemolymph, the β-cyfluthrin exposure increased %prohaemocytes count; diminished %granulocytes and %plasmatocytes count while spherulocyte and oenocyte counts were inconsistent. The alterations in haemocyte counts indicate the immunity response trigger in D. koenigii due to β-cyfluthrin-induced stress. Further investigations may decipher the mechanisms involved and help to formulate the strategies for its management in fields.

Effect of chilling on pupal developmental arrest and subsequent impact on quality control parameters of adult blowfly, Lucilia cuprina (Diptera: Calliphoridae)

The chilling process will surely be a very cost-effective measure for repeated mass rearing and be an effective source for the requirements of a huge number of pupae collected and supplied for the sterile insect technique (SIT) program. In Bangladesh, blowfly (Lucilia cuprina) is a main cause of damage of marine fish during sun drying in coastal areas. The chilling for a certain duration at a certain temperature may store pupae for a specific time by reducing their metabolism. In this study, the effect of chilling temperature and exposure period on pupal developmental arrest was assessed and the subsequent impact on quality control parameters of the adult blowfly, L. cuprina was also observed. We considered the effects of three temperature (4, 7, and 10 °C) regimes and three exposure periods (10, 20, and 30 days) on 3-day-old pupae. Results showed that all the parameters were affected significantly by all the chilling temperatures and durations. Adult emergence, flight ability, pupal weight, adult longevity, fecundity, and fertility decreased with the increase of exposure duration, but partial emergence and pupal duration increased with exposure durations. Storages at 4 °C for 20 and 30 days had no adult emergence. Emergence occurred before the chilling duration at 10 °C for 20 and 30 days which clearly indicated the unsuitable condition for storage parameters. Though the emergence, flight ability, pupal weight, and longevity at 10 °C for 10 days had no significant difference with control, the fecundity and fertility did have a significant difference. In addition, treatment at 7 °C for 10days, the adult emergence, flight ability, pupal weight, longevity, fecundity, fertility, pre-oviposition, and oviposition period had no significant difference with control. Considering all the parameters, it can be concluded that the pupae of L. cuprina can be stored at 7 °C of chilling temperature for 10 days long without any deterioration towards the quality of adult flies.

High-temperature sintering resistance of novel NdYbZr2O7 thermal barrier coating

Ceramic materials of thermal barrier coatings (TBCs) inevitably undergo sintering during long-term service, which can deteriorate the performance at high temperatures. Sintering behavior is commonly a key index for evaluating the application potential of TBCs. Here, we conducted the thermal exposure experiments on the novel NdYbZr2O7 coating at 1300 °C. Results show that multipoint connection is the dominant sintering mechanism. Based on the porosity evolution, the whole sintering process is divided into two stages: 1) stage I characterized by the healing of most equal-width intrasplat cracks and narrow tip of wedge-like intersplat cracks, and 2) stage II characterized by the healing of residual wide part of intersplat cracks. As the thermal exposure duration increases, thermal conductivity of coating at 800 °C increases from ~0.72 W⋅m−1⋅K−1 to ~1.19 W⋅m−1⋅K−1. The linear correlation between the porosity and thermal conductivity indicates that porosity is the critical factor controlling the thermal conductivity of the coating. In comparison with other coatings such as YSZ and SrAl12O19 reported in previous literature, NdYbZr2O7 coating exhibits better thermal insulation and higher sintering resistance. In addition, Young's modulus of coating first rapidly increases and then slowly with time, closely associated with the evolution of porosity.

Bisphenol A-induced neurobehavioral transformation is associated with augmented monoamine oxidase activity and neurodegeneration in zebrafish brain

As bisphenol A (BPA) effortlessly crosses the blood-brain barrier, its serious impacts on the neuronal microenvironment towards precocious induction of oxidative stress and neuromorphological alteration can’t be ignored. Incidentally, a symmetric study establishing the possible link of transformed neurobehavior with heightened monoamine oxidase (MAO) activity and neuromorphological alteration in zebrafish brain subsequent to BPA-exposure is limiting in the literature. The study was conducted to delineate the role of BPA towards the genesis of aggressive behaviour in zebrafish and its correlation with brain MAO activity. Mirror biting test and open field test were conducted to evaluate the aggressive and explorative behaviour respectively. Biochemical studies were performed to delineate the modulation of the antioxidant defence system. Cresyl violet staining and Hoechst staining in the periventricular grey zone of the zebrafish brain were conducted to evaluate neuronal pyknosis and chromatin condensation. Our study showed that BPA exposure is associated with the genesis of aggressive neurobehavioral response. Moreover, the brain MAO activity, oxidative stress and chromatin condensation were increased with increase in exposure duration. The results of the present study gave conclusive evidence that BPA act as a potent neurotoxicant in transforming the native neurobehavioral response of zebrafish through heightened oxidative stress, MAO activity and altered neuromorphology.

Biochemical responses of hairgrass (Deschampsia caespitosa) to hydrological change.

Plant growth and development are closely related to water availability. Water deficit and water excess are detrimental to plants, causing a series of damage to plant morphology, physiological and biochemical processes. In the long evolutionary process, plants have evolved an array of complex mechanisms to combat against stressful conditions. In the present study, the duration-dependent changes in ascorbate (AsA) and glutathione (GSH) contents and activities of enzymes involved in the AsA-GSH cycle in hairgrass (Deschampsia caespitosa) in response to water stress was investigated in a pot trial using a complete random block design. The treatments were as follows: (1) heavily waterlogging, (2) moderate waterlogging, (3) light waterlogging, (4) light drought, (5) moderate drought, (6) heavily drought, and (7) a control (CK) with plant be maintained at optimum water availability. The hairgrass plants were subjected to waterlogging or drought for 7, 14, 21 and 28 days and data were measured following treatment. Results revealed that hairgrass subjected to water stress can stimulate enzymatic activities of ascorbate peroxidase (APX), glutathione peroxidase (GPX), glutathione reductase (GR), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDHAR) and L-galactono-1, 4-lactone dehydrogenase (GalLDH), switched on the ascorbate-glutathione (AsA-GSH) cycle and the L-galactose synthesis, up-regulated the contents of AsA and GSH, and maintained higher ratios of ascorbate to dehydroascorbate (AsA/DHA) and reduced glutathione to oxidized glutathione (GSH/GSSG) to alleviate potential oxidative damage. However, the light waterlogging did not induce hairgrass under stress to switch on the AsA-GSH pathway. In general, the critic substances and enzyme activities in AsA-GSH metabolic pathway increased as the increase of water stress intensity. As the increase of exposure duration, the critic antioxidant substances content and enzyme activities increased first and then maintained a relatively stable higher level. Our findings provide comprehensive information on biochemical responses of hairgrass to hydrological change, which would be a major step for accelerating ecological restoration of degradation alpine marshes in the Qinghai-Tibetan Plateau.

Migration of bisphenol A from epoxy-can malt drink under various storage conditions and evaluation of its health risk

ABSTRACT Bisphenol-A (BPA) is a notable endocrine disrupting chemical and a core raw material utilised in the manufacture of some food contact materials such as epoxy resin and polycarbonate (PC) plastics. The human health risk (HRI) associated with the migration of BPA into malt drinks packaged in epoxy-cans and stored under various conditions was investigated. Solid-phase extraction (SPE) was used to extract BPA, while analysis was performed with a high performance liquid chromatography coupled to an ultraviolet detector (HPLC-UV). The health risk index was used to assess the likelihood of developing chronic non-carcinogenic health risk among consumers of epoxy-can malt drink. Results showed BPA concentrations at 3.98 ± 0.05°C, 25.34 ± 0.70°C and 30.98 ± 0.27°C range from 0.0166 to 0.0300 μg L−1, 0.0188 to 0.0788 μg L−1 and 0.0217 to 0.2131 μg L−1 respectively. BPA levels in the samples did not exceed the European Union limit (50 μg kg−1). Enrichment levels of BPA in samples stored at 30.98 ± 0.27°C were highest, while that at 3.98 ± 0.05°C samples were the least. Initial migration rate of BPA at 3.98 ± 0.05°C and 25.34 ± 0.70°C decreased with increasing exposure duration, and later maintained a mildly constant rate at longer exposure duration. However, at 30.98 ± 0.27°C, BPA migration rates decreased initially with increase in exposure duration, and increased later at prolonged exposure. Although BPA concentrations showed no significant difference (p > 0.05) at the study’s storage conditions, a significant difference (p < 0.05) was observed in BPA migration rates. The computed chronic non-carcinogenic health risk for daily ingestion of malt drink contaminated with BPA by both adults and children was less than one indicating no probable adverse health effect from consumption of the malt drink.

Influence of Magnetic Water on Concrete Properties with Different Magnetic Field Exposure Times.

The characteristics of a concrete mix are purely dependent on the hydration of cement that is carried forward by using the water quality used in the mix. Several researchers have focused on incorporating pozzolanic or nanomaterials to improve the hydration mechanisms and impart high strength to concrete. A new technology has been introduced to improve the properties of concrete by magnetic-field-treated water (MFTW). Due to magnetization, water particles become charged and the molecules inside the water cluster decrease from 13 to 5 or 6, which eventually decreases the hardness of water, thus improving the strength of concrete when compared to the use of normal water (NW). In advanced construction techniques and practices, the application of Magnetic Water (MW) plays an important role in boosting physicochemical properties. This research work focused on evaluating the standards of water quality through physiochemical analysis, such as Electrical Conductivity (EC), Viscosity, pH, and Total Dissolved Solids (TDS) with the MW at different exposure periods (60 min (MW60), 45 min (MW45), 30 min (MW30), 15 min (MW15), and instant exposure (MWI)). Experiments were carried out to evaluate the fresh, hardened, and microstructural behavior of concrete made with magnetic water (MW) using a permanent magnet of PERMAG (N407) under a field intensity of 0.9 Tesla. In addition, optical properties such as X-ray Diffraction (XRD) and Ultraviolet (UV) absorption were considered for the MW60 mix to ensure water magnetization. Characterization methods such as Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetric Analysis (TGA), and Scanning Electron Microscopy (SEM) were employed for NWC and MWC to quantify the hydrated products. From the results, it was observed that the magnetic effect on water characteristics showed significant improvement in the concrete properties with the increase in exposure duration. There were increments of 25.6% and 24.1% in workability and compressive strength, respectively, for the MW60 mix compared to normal water concrete (NWC).

Study of lung function tests in tea garden factory workers in relation to duration of exposure to tea dust

Background: Occupational hazard is a common health problem in the world today. The tea industry is also no exception. Tea dust inhalation leads to development of many respiratory symptoms: Acute as well as chronic. Workers in the tea factory often are not aware of the ill effects of inhalation of tea dust. There is therefore a need to make them aware of their working environment and take necessary precautions to keep themselves healthy to earn their livelihood. Aims and Objectives: The aim of the study was to assess the pulmonary function tests (PFT) in tea garden factory workers and assess the outcome of exposure duration to tea dust in them. Materials and Methods: The study had been carried out on 210 male tea garden factory workers (cases) and 70 male field workers (control) employed in various tea gardens of Dibrugarh, in Assam. Computerized spirometer was used to evaluate PFTs. The cases were categorized into three categories (70 numbers in every category) according to their exposure duration, namely – Category 1: Exposure duration &lt;1 year; Category 2: Exposure duration of 1–2 years; and Category 3: Exposure duration of &gt;2 years up to 5 years. Statistical analysis was done using ANOVA. Results: On comparing with control group values, statistically significant decline of forced vital capacity and forced expiratory volume (FEV)1 values were seen in Category 1 while highly significant decline were seen for Categories 2 and 3. Decline of FEV1% in Category 3 was highly significant. Decline of peaked expiratory flow rate values in Category 2 and Category 3 was significant. Conclusion: Increase in exposure duration to tea dust causes a significant decline in lung functions.

Elevated White Blood Cell Count Is Associated with an Increased Risk of Insulin Resistance among Non-Diabetic Taxi-Motorbike Drivers Working in Cotonou, Benin

High white blood cell count (WBC) and insulin resistance (IR) are interrelated events that contribute to non-communicable diseases (NCDs), including type-2 diabetes (T2D). However, associations between IR and hematological parameters have never been explored in populations of Benin. The aims of this study were to determine the prevalence of IR and associated hematological parameters in taxi-motorbike drivers (TMDs) working in Cotonou. A total of 133 participants were analyzed in this cross-sectional study. Complete blood count, including WBC and platelet, as well as fasting plasma glucose and insulin, were performed by standard procedures. IR was assessed using the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). Factors associated with IR, their odds ratios (ORs) and 95% confidence intervals (CIs) were determined by logistic regression analysis. The mean age of the study participants was 39.3 years. The HOMA-IR cut-off (75th percentile) for IR was 5.9. The overall prevalence of IR was 24.1%. IR increased with the increase of exposure duration and WBC levels. Logistic regression analysis revealed that the risk of IR increased significantly with higher total WBC, with adjusted ORs (95% CI) for the second and third tertiles of 3.56 (1.10 - 11.58) and 4.01 (1.21 - 13.31), respectively. Similar patterns of associations were observed in an analysis restricted to non-drinkers, although these estimates lacked statistical significance. BMI > 24.2 kg/m2 was independently associated with an increased risk of IR (OR = 3.82, 95% CI: 1.33 - 11.03, P = 0.013). In conclusion, the prevalence of IR in TMDs was 24.1%. IR was significantly associated with elevated WBC count and BMI. WBC may serve as a biomarker to identify individuals at the greatest IR risk.

Association between environmental tobacco smoke exposure in early life and autistic-like behaviors in Chinese preschoolers

ObjectiveFew studies have evaluated the association between children's exposure to environmental tobacco smoke (ETS) in early life (during pregnancy, from birth to one year and from one to three years) and autistic-like behaviors. This study aimed to explore this association. MethodsThis cross-sectional study analyzed data collected in 2017 as part of the Longhua Child Cohort Study. Autistic-like behaviors were measured using the Autism Behavior Checklist (ABC). Data on ETS exposure and autistic-like behaviors of children were collected via self-administered questionnaires completed by the mothers. Multivariate logistic regression models were undertaken to assess the associations. ResultsOf the 65,243 participants included in this study, 1958 children met criteria for having autistic-like behaviors. The results showed that children were more likely to exhibit autistic-like behaviors when they were exposed to ETS in early life (AOR = 1.38; 95% CI = 1.26–1.52), compared to preschoolers without ETS exposure at any period of their early life. Compared with their unexposed counterparts, children who were exposed to ETS during gestation (AOR = 1.42; 95% CI = 1.29–1.57), or from birth to one year old (AOR = 1.42; 95% CI = 1.19–1.69) had significantly increased risk of autistic-like behaviors. In addition, with the increase in duration of exposure and average number of cigarettes smoked in the child's immediate environment, the risk of autistic-like behaviors increased. ConclusionOur study indicated that children's ETS exposure in early life was significantly associated with autistic-like behaviors. When children's exposure to cigarettes in early life increased in duration and number, the likelihood of the presence of autistic-like behaviors was higher.

High thermal plasticity, and vulnerability, in extreme environments at the warm distributional edge: The case of a tidepool shrimp

Climate change threatens the resilience of species, especially at their warm distributional edge in extreme environments. We investigated the thermal vulnerability of the tidepool shrimp, Palaemon elegans in the fast-warming southeastern Mediterranean Sea, its warm distributional edge. Tidepool organisms experience strong and fast thermal fluctuations. This might make them more resilient to change, but also bring them closer to their thermal limits during extreme conditions. To examine the shrimp's resilience, we tested three hypotheses: (1) P. elegance in the southeast Mediterranean has higher critical thermal maximum (CTMax) than in cooler regions, (2) the shrimp possess seasonal acclimatization, but (3) long exposure to extreme summer temperatures might erode its thermal performance making it vulnerable to future climate change. In a series of field observations and laboratory experiments we characterized the shrimp's thermal environment and population dynamics, determined its CTMax and tested diverse physiological performance attributes (respiration, digestion, activity, growth) under a wide range of temperatures during winter and summer. The thermal performance curves show that peak respiration rates occur at higher temperatures in the summer compared to winter, indicating seasonal acclimatization. The shrimp's CTMax was 38.1 °C; higher than its Atlantic counterparts, and an indication of biogeographic adaptation. However, its warming tolerance (the thermal safety margin: distance between maximum pool temperatures and CTMax) was only 0.3 °C, indicating low capacity for dealing with further warming in mostly isolated pools, compared to northeast Atlantic populations that have a wider safety margin. Performance also eroded with increase in exposure duration to high temperatures, and the optimum temperature reduces with time. We predict that prolonged exposure to current (~ 32 °C) and future mean summer values in open water would significantly reduce its performance and increase its mortality. Further, juvenile P. elegans were found to be more vulnerable to extreme (cold and hot) temperatures than adults. Together, these findings indicate that the population viability of this robust coastal water shrimp would eventually be reduced under continuous regional warming and the intensification of extreme events.

Photocatalytic activity of biogenic zinc oxide nanoparticles: In vitro antimicrobial, biocompatibility, and molecular docking studies

Abstract The biogenic synthesis of zinc oxide nanoparticles (ZnO NPs) with pinecone extract (PCE) as a reducing agent and antibacterial agent was explored. The current study aims to investigate the biosynthesis of ZnO NPs and their effect on photocatalytic dye degradation and antimicrobial properties. The physical, chemical, and morphological properties of biogenic ZnO NPs synthesized using PCE were investigated using advanced spectroscopy techniques such as Fourier transform infrared spectroscopy (FTIR), UV-visible spectroscopy, transmission electron microscopy (TEM) analysis, selected area electron diffraction (SAED), and X-ray diffraction (XRD) techniques. The photocatalytic degradation of methylene blue was measured spectrophotometrically using biogenic ZnO NPs as nanocatalysts, and decolonization of solution indicates dye degradation gradually as exposure duration increases. The antimicrobial properties of ZnONPs against the tested pathogenic strains were demonstrated using the disc diffusion method. The antimicrobial efficacy of ZnONPs was further explained using molecular docking analysis. Confirmation of the lowest binding energy was used to predict receptor binding site with NPs in order to understand the mechanistic approach. ZnONPs are likely to interact with pathogens via mechanical enfolding, which could be one of the major toxicity actions of ZnONPs against strains. Furthermore, the nontoxicity and biocompatibility of ZnO NPs were studied, revealing impressive hemocompatibility with red blood cells (RBCs) and no significant toxicity to Brine shrimps at lower ZnONP concentrations.

Impact of Exposure of Chemical Fumes on Blood Pressure and Peak Expiratory Flow Rate in Industrial Workers of Faisalabad

Objectives: 1. To determine the impact of duration of exposure to industrial chemical fumes on Peak Expiratory Flow Rate (PEFR) and blood pressure of the industrial workers. 2. To find out the association between changes in blood pressure and PEFR due to exposure to industrial chemical fumes in these subjects. Methods: This cross-sectional study was performed at Aziz Fatimah Medical and Dental College, Faisalabad. The study participants were 151 males working in the chemical industries. The study was approved by institutional ethical committee and informed consent was taken from the participants. Free camp was arranged for three days in September 2020 in the industrial area of Faisalabad. Thorough history of exposure to chemicals was taken using structured proforma. PEFR values were recorded using Wrights handheld peak flow meter. Blood pressure was taken by auscultatory method using mercury sphygmomanometer. Data was analyzed using SPSS version 22. Results: Systolic and diastolic blood pressures were significantly raised with increase in duration of exposure. PEFR levels were significantly declined with increase in duration of exposure to chemicals. Significant negative association was noted between diastolic blood pressure and PEFR (p value = 0.003). Negative correlation was observed between PEFR and systolic Blood pressure, however it was not statistically significant (p value = 0.92). Conclusions: PEFR decreased while Systolic and diastolic blood pressures increased significantly with increase in the duration of exposure to chemicals. There was a significant negative correlation between PEFR and diastolic blood pressure while there was no association between PEFR and systolic blood pressure.