Duration Of Exposure Research Articles

Effects of Automation Exposure and Non-Driving Related Tasks on Manual Driving Performance after Takeover of Manual Control

Prolonged exposure to an automated driving system (ADS) can lead drivers to acclimate to the ADS in maladaptive ways. For example, exposure to a conditional ADS that maintained a time headway of 0.3 s resulted in drivers adopting smaller time headways postautomation, which is attributed to behavioral adaptation. The current study investigated whether drivers adapt to an ADS’ performance over time and if this adaptation differs based on the duration of automation exposure (15 or 25 min) and the task performed during the automation (NDRT or driving-related task). A greater exposure to the automation did not lead drivers to adopt smaller time headways. Surprisingly, drivers who provided a higher evaluation of the automation adopted smaller time headways post-automation than drivers who provided a lower evaluation. Future research should explore the relationship between trust in ADS and driving behavior to guide the development of safer ADSs.

Impact of UV Light Exposure During Printing on Thermomechanical Properties of 3D-Printed Polyurethane-Based Orthodontic Aligners

Aim: Polyurethane-based aligners, created through photoinitiated free-radical polymerization, have been the subject of numerous studies focusing solely on their mechanical properties. In contrast, we investigate their thermomechanical properties, which are crucial for their efficacy. This paper aims to investigate the effects of different UV light exposure durations on the complex modulus of elasticity, tan delta, glass transition temperature, and the degree of conversion (DC). Methods: Aligners were printed using Tera Harz TC-85 and NextDent Ortho Flex resin with specific exposure times (2, 2.4, 3, 4, and 4.5 s for Tera Harz; 5, 6, 7, and 8 s for NextDent) and processed per manufacturer guidelines. The degree of conversion was analyzed using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy, while Dynamic Mechanical Analysis (DMA) characterized the mechanical properties (complex modulus and tan delta) and the glass transition. Results: Tera Harz TC-85 showed a higher degree of conversion (90.29–94.54%), suggesting fewer residual monomers, which is potentially healthier for patients. However, its lower glass transition temperature (35.60–38.74 °C) might cause it to become rubbery in the mouth. NextDent Orto Flex, with a higher storage modulus (641.85–794.55 MPa) and Tg (49.36–50.98 °C), offers greater rigidity and stability at higher temperatures (greater than temperature in the oral cavity), ideal for orthodontic forces, though its lower degree of conversion raises health concerns. Conclusions: Tera Harz TC 85 generally achieves higher DC and more stable polymerization across different UV exposure times than NextDent Orto Flex. Optimal polymerization times significantly impact both the mechanical and thermal properties of these dental resins, with NextDent showing optimal properties at 7 s and Tera Harz benefiting from both very short and extended exposure times.

Examining the Independent and Interactive Carryover Effects of Cognitive and Physical Exertions on Physical Performance.

This study compared the effects of prior cognitive, physical, and concurrent exertion on physical performance. Fatiguing cognitive and physical exertions have been shown to negatively affect subsequent task performance. However, it is not clearly understood if concurrent physical and cognitive effort may exaggerate the negative carryover effects on physical task performance when compared to cognitive or physical exertion alone. Twenty-five participants completed four isometric handgrip endurance trials on different days. The endurance trials were preceded by four, 15-minute experimental manipulations (cognitive, physical, concurrent, control). Electromyography (EMG) and force tracing performance were monitored, with handgrip strength measured pre and post. Subjective ratings of mental and physical fatigue, as well as affect, motivation, and task self-efficacy, were also assessed. Handgrip strength decreased following both physical (-14.4% MVC) and concurrent (-12.3% MVC) exertion manipulations, with no changes being observed for the cognitive and control conditions. No differences were observed across conditions for endurance time, EMG, nor tracing performance. When compared to the control conditions, perceptions of mental and physical fatigue were higher following the experimental manipulation. Endurance trial self-efficacy was lower for the mental, physical and concurrent conditions compared to control. The concurrent condition resulted in similar decreases in strength as the physical fatigue condition, but otherwise resulted in similar carryover effects on endurance performance across all conditions. Further study is required at higher exposure levels, or for longer exposure durations, to further probe the influence of concurrent physical and cognitive effort on task performance. Concurrent cognitive and physical effort resulted in similar physical performance decrements to physical effort alone.

Prevalence and risk factors of myopia among children and adolescents in Hangzhou.

To analyze the prevalence and influencing factors of myopia among children and adolescents in Hangzhou city, and provide ideas for the formulation of myopia prevention and control measures. A cross-sectional school-based study using stratified cluster random sampling method was used to select 31,880 students from 113 schools in Hangzhou city. Myopia screening and questionnaires on the influencing factors of poor visual acuity were carried out. Univariate and multivariate logistic regression were used to screen possible risk factors of myopia. The overall prevalence of myopia was found to be 55.3% (17,630/31,880), with the myopia rates observed among students in kindergarten, primary school, junior high school, and senior high school, at 5.8%, 34.9%, 74.2%, and 85.0%, respectively. As the academic year progresses, there has been an observable increase in the prevalence of myopia (χ2 = 8676.748, P<0.001), low myopia (χ2 = 5444.040, P<0.001) and high myopia (χ2 = 2171.073, P<0.001) among students, with the difference between the three groups being statistically significant. The myopia prevalence in girls is higher than that in boys (χ2 = 119.917, P<0.001); the prevalence of myopia in urban students is higher than that in suburban students (χ2 = 4.603, P = 0.032). The time spent on homework after school, the correctness of reading and writing postures, the duration of exposure to electronic screens, and the use of lighting in an appropriate manner all have an impact on the development of myopia (all P<0.05). The overall prevalence of myopia and high myopia in schools in eastern China, is notably high. The prevalence of myopia and high myopia increases with grade or age. Myopia is associated with increased age, parental myopia, extended periods of homework after school, poor reading and writing posture, prolonged exposure to electronic screens and inappropriate lighting. In light of the findings of the present survey, it is recommended that a comprehensive prevention and control intervention model for myopia in children and adolescents based on society-hospital-school-family-individual students with a view to preventing and controlling myopia.

Assessing the mobility of Zn, Pb and Ni during the weathering of Nkana smelter copper slag, Zambia

Mine slag dumps could be point-sources of possible pollutants to the surrounding water and soils. The purpose of this study was to investigate the leaching behavior of zinc, lead and nickel from Nkana copper slag dump of Kitwe in Zambia. To assess the toxicity and hazardous nature of the slag, Bath Leaching EN 12,457–2:2002, Toxicity Characteristic Leaching Procedure (TCLP) and Synthetic Precipitation Leaching Procedure (SPLP) were employed. The results from these techniques revealed that the copper slag was inert in the open or natural environment. Sequential extraction analysis was conducted to analyze the fractionation of the zinc, lead and nickel using a seven-step procedure. The sequential extraction analysis showed that the 3 metals were predominantly present in the residual fraction. The risk assessment code (RAC) showed that zinc and lead's mobility could pose an environmental risk categorized as low risk, with RAC values of 1.31 % and 1.50 %, respectively. Nickel's mobility fell within the no-risk category with a RAC of 0.32 %. Additionally, the effect of pH, particle size and contact time on the release of the 3 metals were investigated. The results showed that the highest concentrations of zinc and nickel were observed for longer period of exposure (>33 days), in acidic environments (pH 2.2 and pH 3.0), for particle size distribution (<75 μm). However, lead leaching was not affected by the variation of pH or particle size distribution but mostly by duration of exposure. X-ray diffraction (XRD) analysis revealed that diopside (CaMgSi2O6) and quartz (SiO2) constitute the primary phases within the sample. It is recommended to limit the exposure of slag material to acidic environments and minimize the fragmentation of the slag into finer particles as these conditions would promote increased release of zinc, lead and nickel to the surrounding environment.

Behaviour, biochemical and histological responses of the freshwater mussels Unio ravoisieri exposed to wastewater from Wadi Guenniche (Northeastern Tunisia)

ABSTRACT Wastewater effluents increase contaminant levels in the aquatic environment, leading to various disruptive effects. In this study, responses of Unio ravoisieri transplanted into wastewater from Wadi Guenniche were monitored using filtration rate, oxidative stress, lipo-peroxidation, neurotoxicity and histopathological markers. The filtration rate was significantly increased by exposure to diluted wastewater, rising from 35.13 mg indiv−1 h−1 in the control to 63.49 mg indiv−1 h−1 in the mussels after 96 h of exposure. In contrast, this exposure significantly reduces catalase, glutathione-S-transferase and acetylcholinesterase activities in both organs. This decrease is dependent on the effluent concentration and time exposure. The malondihaldehyde content showed an increasing profile in both organs. It is only in the gills that this increase is significant for mussels transplanted in situ for 48 h. Contamination by wastewater causes histopathological changes in both organs, marked by infiltration, vacuolisation, secretion of lipofuscins and cell necrosis. The intensity of these lesions depends on the duration of exposure and the degree of pollution. The mean incidence of lesions increases depending on effluent concentration and exposure time in both organs. Our study contributes to the database on behavioural, biochemical and histopathological effects in mussels following the discharge of wastewater effluent into a freshwater ecosystem.

Time-Dependent Resistance of Sol–Gel HfO2 Films to In Situ High-Temperature Laser Damage

Laser damage in films under long-term high-temperature conditions is a significant concern for advancing laser applications. This study focused on HfO2 films prepared using the sol–gel method with HfCl4 as a precursor. It examined the effects of temperature on various properties of the films, including their optical properties, microstructure, surface morphology, absorption, and laser-induced damage threshold (LIDT). The prepared film demonstrated desirable characteristics at the high temperature of 423 K, such as high transmittance, low absorption, and high LIDT. As the duration of its high-temperature exposure increased, the LIDT of the films gradually decreased. An intriguing finding was that the film’s LIDT exhibited an exponential decay pattern with prolonged heating time. This observation could be attributed to the power-law increase in defects on both the internal and surface areas of the film as the duration of high-temperature exposure lengthened. Moreover, even after a 15-day heating period at 423 K, the film maintained an LIDT of 12.9 J/cm2, indicating its potential applicability in practical high-temperature environments. This study provided a general pattern and a universal formula for understanding the laser damage of sol–gel films at high temperatures over time. Furthermore, it opened possibilities for future developments of laser films suitable for extreme environments.

Characterization of the thermomechanical and aging behaviour of PAEK and CF/PAEK composites under long-term high-temperatures

The growing use of poly(aryl ether ketone) (PAEK) polymers reinforced with carbon fiber (CF) aims to meet the increasing demand for thermoplastic composites in applications that require excellent mechanical properties and thermal stability at higher temperatures. This study investigated the physicochemical properties of PAEK and CF/PAEK composites under long-term high-temperature exposure (150 °C, 200 °C and 250 °C) for durations of 15, 30, and 45 days, aiming to elucidate the durability mechanisms and enhance understanding of their performance. Specifically, the changes in the flexural properties and dynamic thermo-mechanical properties of the materials were evaluated after long-term high-temperature treatment. The results indicated that both PAEK and CF/PAEK composites possess substantial potential for long-term high-temperature applications, with CF not significantly altering the fundamental high-temperature response of the PAEK matrix. Regarding durability mechanisms, at 150 °C, PAEK's amorphous region undergoes chain reorientation, while temperatures of 200 °C and 250 °C induce significant secondary crystallization, which significantly improved the high-temperature mechanical properties of these materials. Additionally, at temperatures up to 250 °C, shorter linear chain fragments form through oxidative scission in PAEK's amorphous molecular chains. This work not only enriches the existing data on the properties of PAEK and CF/PAEK composites after long-term high-temperature treatment, but also provides further insights into their durability mechanisms.

Optimizing Electron‐Beam Photothermal Pyrolysis Parameters for Enhanced Molecular Biodegradability of Polyvinyl Chloride Plastics

AbstractPolyvinyl chloride (PVC), a synthetic plastic notable for harmful emissions during deterioration, has potential to be molecularly adjusted by photo‐oxidative ultraviolet degradation. This research investigates the influence of electron beam irradiation and near‐infrared photothermal treatment utilizing gold nanoparticles to establish the optimized molecular weight and beam time exposure for biodegradable PVC properties while maintaining a minimum tensile strength as measured through the ratio of peak tension force by cross sectional area. PVC powder samples with number‐average molecular weights ranging from 20.0 to 90.0 kDa and varying exposure times of a 100 kGy electron beam from 80 to 115 ms are employed for the study. Outcomes from PVC irradiation reveal the optimal parameters for inducing biodegradability in samples: an e‐beam exposure duration of 95 ms applied to PVC powder with a sample molecular weight of 20.0 kDa. Analysis of the ratio of number average molecular weight and weight average molecular weight demonstrates that shorter irradiation durations result in lower molecular weights and molecular weight is directly proportional to Tg and crystallinity. Future work aims to scale up the procedure to industrial applications and investigate the treatment's applicability to a variety of thermoplastics.

Hyperbaric oxygen rapidly produces intracellular bioenergetics dysfunction in human pulmonary cells

Hyperoxic exposure lasting days alters mitochondrial bioenergetic and dynamic functions in pulmonary cells as indices of oxygen toxicity. The aim of this study was to examine effects of short duration hyperbaric and hyperoxic exposures to induce oxygen toxicity similarly. Cultured human lung microvascular endothelial cells, human pulmonary artery endothelial cells and A549 cells were exposed to hyperoxia (∼5 % CO2 equivalent, balance O2) under hyperbaric conditions (4.8 ATA) for 1 and 4 h. Measures of mitochondrial dynamics, inner membrane potential, mitochondrial respiration, the intracellular distribution of bioenergetic capacity and respiration complex protein levels were then quantified. Exposures resulted in altered mitochondrial motility, presence of inhomogeneities in respiration parameters, loss of inner membrane potential, and changes in intracellular partitioning of ATP-linked respiration. Changes in the levels of respiration complex protein levels were also found. The combination of hyperoxic exposure with hyperbaric conditions rapidly produced changes in mitochondrial dynamics and bioenergetics in pulmonary cells. These changes are consistent with the onset of pulmonary oxygen toxicity previously known to result from long duration exposure to hyperoxia alone. These findings suggest health caution is warranted in environmental settings in which both hyperoxic and hyperbaric conditions are present. The synergism of hyperoxia and hyperbaria for rapid induction of oxygen toxicity in cellular models has utility for the study of mechanistic determinants of oxygen toxicity, testing of putative therapeutics, and associated investigations of mitochondrial dysfunction.

Are Microfibers a Threat to Marine Invertebrates? A Sea Urchin Toxicity Assessment.

The rise of "fast fashion" has driven up the production of low-cost, short-lived clothing, significantly increasing global textile fiber production and, consequently, exacerbating environmental pollution. This study investigated the ecotoxicological effects of different types of anthropogenic microfibers-cotton, polyester, and mixed fibers (50% cotton: 50% polyester)-on marine organisms, specifically sea urchin embryos. All tested fibers exhibited toxicity, with cotton fibers causing notable effects on embryonic development even at environmentally relevant concentrations. The research also simulated a scenario where microfibers were immersed in seawater for 30 days to assess changes in toxicity over time. The results showed that the toxicity of microfibers increased with both concentration and exposure duration, with polyester being the most toxic among the fibers tested. Although synthetic fibers have been the primary focus of previous research, this study highlights that natural fibers like cotton, which are often overlooked, can also be toxic due to the presence of harmful additives. These natural fibers, despite decomposing faster than synthetic ones, can persist in aquatic environments for extended periods. The findings underline the critical need for further research on both natural and synthetic microfibers to understand their environmental impact and potential threats to marine ecosystems and sea urchin populations.

Quantitative evaluation of anti-biofilm cavitation activity seeded from microbubbles or protein cavitation nuclei by passive acoustic mapping

Bacterial biofilms represent a major challenge for effective antibiotic therapy as they confer physical and functional changes that protect bacteria from their surrounding environment. In this work, focused ultrasound in combination with cavitation nuclei was used to disrupt biofilms of Staphylococcus aureus and Pseudomonas aeruginosa, both of which are on the World Health Organization's priority list for new antimicrobial research. &#xD;Approach: Single species biofilms were exposed to ultrasound (0.5 MHz centre frequency, 0.5-1.5 MPa peak rarefactional pressure, 200 cycle pulses, 5 Hz repetition frequency, 30 s duration), in the presence of two different types of cavitation nuclei. Quantitative passive acoustic mapping (PAM) was used to monitor cavitation emissions during treatment using a calibrated linear array. &#xD;Main Results: It was observed that the cumulative energy of acoustic emissions during treatment was positively correlated with biofilm disruption, with differences between bacterial species attributed to differences in biofilm morphology. PCaN provided increased biofilm reduction compared to microbubbles due in large part to their persistence over the duration of ultrasound exposure. There was also good correlation between the spatial distribution of cavitation as characterized by PAM and the extent of biofilm disruption observed with microscopy. &#xD;Significance: Collectively, the results from this work indicate the potential broad applicability of cavitation for eliminating biofilms of priority pathogens and the opportunity presented by Passive Acoustic Mapping for real-time monitoring of antimicrobial processes.

An assessment of in vitro lead (Pb) bioaccumulation of Dianthus chinensis L. (Chinese pink).

Heavy metals (HM) also known as potentially toxic elements (PTEs), are well-known environmental pollutants, among which lead (Pb) is a widespread and hazardous soil contaminant. Its removal from soil sediments is often difficult to achieve. In this study, in vitro experiments were conducted to investigate the bioaccumulation capability of Dianthus chinensis L. in solid and liquid Murashige and Skoog (MS) medium supplemented with varying concentrations (0, 10, 100, and 200µM) of Pb as lead nitrate [Pb(NO3)2] for 30days. The objectives of the study were to assess the efficiency of the selected plant as a bio-accumulator in the in vitro system and to obtain data on morphological, biochemical, and molecular changes during Pb salt-induced stress. Significant growth patterns of initial growth promotion up to 100µM lead nitrate supplemented medium were observed, with maximum shoot length and biomass production along with remarkable lead bioaccumulation. Molecular studies on in vitro raised plantlets confirm the high degree of genetic uniformity (98.3%) of the selected plants after a considerable duration (30days) of Pb exposure. Biochemical parameters revealed significant stress effects, including a 284% reduction in total chlorophyll content, altered carotenoid, and proline level during the study. The experiment revealed the high tolerance capacity of D. chinensis to Pb salt and its bioaccumulation potential (397.33mg/kg). This increases the possible use of such an ornamental and floriculture plant as a prospective candidate for the efficient removal of soil Pb pollutants, as they can remediate soils, coupled with aesthetic and profitable outcomes for the growers.

The Harmful Effects of Welding Fumes on Human Dental Enamel-A Microhardness Analysis.

Introduction: Over the years, welding fumes' harmful effects have been demonstrated countless times in the scientific literature. Recently, studies in the field have shown an increasing interest in the negative consequences that these fumes may have on the tissues of the oral cavity. Materials & method: The current study aimed to investigate the impact that welding fumes have on the structure of human dental enamel by analyzing the microhardness of the dental enamel in 15 extracted human teeth, after various exposure times, using the Vickers method. Results: The results obtained after 48, 96, 168, and 336 h of direct exposure of the extracted specimens to the welding fumes show a statistically significant increase in the depreciation of the dental enamel's microhardness, related to the duration of exposure (p < 0.05). An average of 305 Vickers units was observed at the longest exposure time, 336 h, in the present study, whereas in the control group, the microhardness analysis showed an average of 327 Vickers units.

Influence of Ensiling Timing and Inoculation on Whole Plant Maize Silage Fermentation and Aerobic Stability (Preliminary Research)

Despite efforts to prevent atypical ensiling conditions, such as delayed ensiling or sealing, these issues frequently occur in practice. This study aimed to investigate the effects of delayed ensiling (forage held for 24 h) and sealing, along with inoculation using a blend of Lentilactobacillus buchneri and Lactococcus lactis, on the characteristics of the resulting silages. Whole-plant maize (Zea mays L.) was treated with or without a commercial inoculant and ensiled (36% dry matter) for 60 days in 3.0 L glass containers. The forage was either ensiled immediately or subjected to a 24 h delay before ensiling. During the delay, the forage was either covered or left uncovered. Each treatment was replicated five times. All data were analyzed using the MIXED procedure of SAS statistical software (version 9.4; SAS Institute Inc., Cary, NC, USA). Delaying the ensiling process by 24 h worsens fermentation parameters, significantly increases dry matter (DM) losses (p &lt; 0.01), and significantly reduces aerobic stability and the hygienic quality of the silage (p &lt; 0.01), as evidenced by higher concentrations of undesirable fermentation products and elevated yeast and mold counts. The inoculation has a significant impact on both forage before ensiling and the characteristics of the resulting silage. Maize forage treated with inoculant showed a lower temperature increase by 8.2–8.1 °C (p &lt; 0.01) when delayed for 24 h before ensiling. In silages, it also resulted in a reduced pH (p &lt; 0.01); increased concentrations of lactic acid; acetic acid; and 1,2-propanediol (p &lt; 0.01); and decreased levels of negative fermentation indicators such as ammonia-N, alcohols, and butyric acid (p &lt; 0.01) During both the fermentation and aerobic exposure periods, inoculated silages exhibited up to 36% and 2.6 times lower (p &lt; 0.01) dry matter loss, while suppressing the growth of yeasts and molds by up to 2.6 and 3.1 times (p &lt; 0.01), respectively, compared to non-inoculated silages. The results of this study support the recommendation to minimize the duration of aerobic exposure of fresh forage during silo filling and to use LAB-based inoculants.

Compressive strength of nano concrete materials under elevated temperatures using machine learning

In this study, four Artificial intelligence (AI) - based machine learning models were developed to estimate the Residual compressive strength (RCS) value of concrete supported with nano additives of Nanocarbon tubes (NCTs) and Nano alumina (NAl), after exposure to elevated temperatures ranging from 200 to 800 degrees. These models were developed via adapting meta- heuristic models including the Water cycle algorithm (WCA), Genetic algorithm (GA), and classical AI models of Artificial neural networks (ANNs), Fuzzy logic models (FLM), in addition to the statistical method of Multiple linear regression (MLR). 156 post heating experimental results available as a literature data (represents four input parameters of temperature change, heat exposure duration, nanomaterial type, and replacement proportion) are used to achieve the study’s objective. Results of the developed models demonstrated that ANN and FLM have strong potential in predicting RCS. However, it is often infeasible to generate practical equations that relate input and output variables from these models. Upon analysing the results of the WCA and GA, it was found that WCA yielded the most accurate predictions based on all performance indicators. Furthermore, RCS prediction equations with superior accuracy were derived utilizing the meta-heuristic AI models of WCA and GA, with Mean absolute errors (MAEs) of 3.09 kg/cm² and 3.53 kg/cm² for the training, 1.91 kg/cm² and 2.72 kg/cm² for the validation, and 1.91 kg/cm² and 2.72 kg/cm² for the testing data sets, respectively. Additionally, sensitivity analysis via neural networks weights and SHAP investigation were performed to reveals the impact and relationship of the input variables with the output variables. Both techniques reveal that temperature degree and time of exposure had the highest positive impact on RCS value, followed by NAl and NCTs, in order.

Sub-Acute Toxicity Assay of the smoke of Seeds of Azadirachta indica and Peels of Citrus sinensis used as natural insecticides on the Liver, Kidney, Lungs and Heart of Albino Rats

Abstract Natural plant parts such as seeds of Azadirachta indica (neem seeds) and peels of Citrus sinensis (sweet orange) have been used as house-hold remedies against various ailments and bio-pesticides for agricultural purpose due to their repellent, growth regulatory and anti-feedant properties against insects. Despite their beneficial role, these natural insecticides could also have toxic effects on some vital organs of human. Therefore, this study aimed to investigate the sub-acute toxicity of smoke of the Seeds of Azadirachta indica and Peels of Citrus sinensis on the liver, kidney, lungs and heart of swiss albino rats. In this study, three groups of white swiss albino rats were exposed to the smoke of A indica seeds, peels of C sinensis and their combination at different duration of one hour and two hours respectively. The Control group were not exposed to any of the natural insecticides and were fed normal diet and water. After four weeks of the treatment, the animals were all sacrificed and their liver, kidneys, lung and heart were evaluated using standard biochemical and histopathological techniques. The levels of serum biochemical indices for liver (aspartate amino transferase (AST), alanine amino transferase (ALT), alkaline phosphatase (ALP), total bilirubin and protein), kidneys (urea, creatinine and electrolytes), and heart (creatine kinase and lactate dehydrogenase) were found to be significantly higher at (p&amp;lt;0.05) for all the groups treated with the two natural insecticides when compared to control group. Histopathological changes including fibrosis, hemorrhages, vascular congestion and necrosis were observed in the liver, kidneys and lungs tissues of the rats exposed to the smoke of the seeds of A indica. However, no histopathological changes were observed in all organs of rats exposed to the smoke of the peels of C sinensis compared to control group. Moreover, the severity of the effects of smoke of these natural insecticides on both biochemical and histopathological indices increases with increase in duration of exposure. The results of this study revealed that seeds of A indica have significant toxic effects on both the tissue and biochemical markers of all the major organs of the Swiss albino rats, while peels of C sinensis shows effect on only the biochemical indices at the specific duration of time studied.

Immune Checkpoint Inhibitor Therapy and Associations with Clonal Hematopoiesis

Cancer cohorts are now known to be associated with increased rates of clonal hematopoiesis (CH). We sort to characterize the hematopoietic compartment of patients with melanoma and non-small cell lung cancer (NSCLC) given our recent population level analysis reporting evolving rates of secondary leukemias. The advent of immune checkpoint blockade (ICB) has dramatically changed our understanding of cancer biology and has altered the standards of care for patients. However, the impact of ICB on hematopoietic myeloid clonal expansion remains to be determined. We studied if exposure to ICB therapy affects hematopoietic clonal architecture and if their evolution contributed to altered hematopoiesis. Blood samples from patients with melanoma and NSCLC (n = 142) demonstrated a high prevalence of CH. Serial samples (or post ICB exposure samples; n = 25) were evaluated in melanoma and NSCLC patients. Error-corrected sequencing of a targeted panel of genes recurrently mutated in CH was performed on peripheral blood genomic DNA. In serial sample analysis, we observed that mutations in DNMT3A and TET2 increased in size with longer ICB exposures in the melanoma cohort. We also noted that patients with larger size DNMT3A mutations with further post ICB clone size expansion had longer durations of ICB exposure. All serial samples in this cohort showed a statistically significant change in VAF from baseline. In the serial sample analysis of NSCLC patients, we observed similar epigenetic expansion, although not statistically significant. Our study generates a hypothesis for two important questions: (a) Can DNMT3A or TET2 CH serve as predictors of a response to ICB therapy and serve as a novel biomarker of response to ICB therapy? (b) As ICB-exposed patients continue to live longer, the myeloid clonal expansion may portend an increased risk for subsequent myeloid malignancy development. Until now, the selective pressure of ICB/T-cell activating therapies on hematopoietic stem cells were less known and we report preliminary evidence of clonal expansion in epigenetic modifier genes (also referred to as inflammatory CH genes).

N-Methyl-d-Aspartate Receptor Antibody and Sensory Gating Deficits in Non-smoking, Minimal Antipsychotic Medication Exposure, and First-Episode Patients With Schizophrenia.

Sensory gating deficit is considered a pathophysiological feature of schizophrenia, which has been linked to N-methyl-d-aspartate receptor (NMDAR) hypofunction as one of the potential underlying mechanisms. Here, we hypothesize that higher levels of NMDAR antibody (Ab) may contribute to the sensory gating deficits in schizophrenia. We enrolled 72 non-smoking inpatients with first-episode schizophrenia (FES), most of them with only a relatively short duration of exposure to antipsychotic medications, and 51 non-smoking healthy controls (HC). Sensory gating was measured by P50 evoked potentials ratio and the difference between the two stimuli in an auditory paired-stimuli paradigm and serum NMDAR Ab levels were quantified by enzyme-linked immunosorbent assay. The FES group showed higher serum NMDAR Ab levels [(9.23 ± 4.15) ng/mL vs. (7.08 ± 2.83) ng/mL; P = .002], higher P50 ratio (P = .002), and less P50 difference (P = .001) than HC. In partial correlation analysis, serum NMDAR Ab levels were positively correlated with the P50 ratio (r = 0.36, P = .003) and negatively with the P50 difference (r = -0.39, P = .001) in the FES group. The NMDAR Ab levels mediated the diagnosis of schizophrenia and P50 sensory gating deficits (P50 ratio and P50 difference). Autoimmunity targeting NMDAR is a crucial intermediate mechanism in impaired sensory gating in patients with schizophrenia. The findings support early intervention targeting NMDAR for patients with schizophrenia.

Association between Exposure to Smokeless Tobacco Consumption and Carcinoma of Cervix

Background: Cervical cancer is the most destabilizing cancer that grows increasingly prevalent worldwide. The Southeast Asia region has the greatest incidence and mortality rates due to widespread use of smokeless tobacco (SLT) products, a lack of screening programmes, and immunization against cervical cancer. Objective: To assess the association between smokeless tobacco consumption and carcinoma of cervix. Methodology: A case-control study was conducted with 272 women aged 18-49 years, conveniently selected from both outpatient and inpatient settings at the National Institute of Cancer Research and Hospital (NICRH) in Dhaka, Bangladesh. The selection of NICRH was purposive. Participants underwent interviews using a pre-tested, semi-structured questionnaire between January and December 2019. Results: The mean age of cases was 49.8±8.8 years, while the mean age of controls was 48.5±9.3 years. In comparison to controls (52.2%), the majority of patients (65.4%) consumed SLT throughout their entire lives. A significant relationship was found between SLT use and the development of cervical cancer (p&lt;0.05). Those who have consumed any SLT in their lives are 1.7 times more likely to develop cervical cancer than those who have not taken any SLT. Cases (22.8%) used betel quid with jorda &gt;5 times, compared to controls (14.7%), and intensity of Gul used ≤5 among cases (9.6%) than controls (2.9%). Compared to controls (56.3%), the majority of cases (76.4%) had been using SLT for more than 10 years, with a statistically significant difference (p&lt;0.05). Cases used SLT for a longer time (19.2±10.3) compared to controls (15.6±11.1), with a significant association (p&lt;0.05). Conclusion: The study revealed a significant association between the risk of cervical cancer and the extent and duration of exposure to SLT. To minimize the risk of cervical cancer, contemplate restricting SLT production and utilization. Journal of Monno Medical College June, 2024; 10 (1):17-22