Selenium nanoparticles induce coumarin metabolism and essential oil production in Trachyspermum ammi under future climate CO2 conditions.

Research on nanoparticles (NPs) and future elevated CO2 (eCO2) is extensive, but the effects of SeNPs on plant growth and secondary metabolism under eCO2 remain uncertain. In this study, we explored the impact of SeNPs and/or eCO2 on the growth, physiology, chemical composition (primary metabolites, coumarins, and essential oils), and antioxidant capacity of Trachyspermum (T.) ammi. The treatment with SeNPs notably improved the biomass and photosynthesis of T. ammi plants, particularly under eCO2 conditions. Plant fresh and dry weights were improved by about 19, 33 and 36% in groups treated by SeNPs, eCO2, and SeNPs + eCO2, respectively. SeNPs + eCO2 induced photosynthesis, consequently enhancing sugar and amino acid levels. Similar to the increase in total sugars, amino acids showed variable enhancements ranging from 6 to 42% upon treatment with SeNPs + eCO2. At the level of the secondary metabolites, SeNPs + eCO2 substantially augmented coumarin biosynthesis and essential oil accumulation. Consistently, there were increases in coumarins and essential oil precursors (shikimic and cinnamic acids) and their biosynthetic enzymes. The enhanced accumulation of coumarins and essential oils resulted in increased overall antioxidant activity, as evidenced by improvements in FRAP, ORAC, TBARS, conjugated dienes, and inhibition % of hemolysis. Conclusively, the application of SeNPs demonstrates significant enhancements in plant growth and metabolism under future CO2 conditions, notably concerning coumarin metabolism and essential oil production of T. ammi.

Sleep Patterns of Pilots: An Objective Assessment.

Objectives Circadian dysregulation (jetlag), sleep loss (extended wakefulness), sleep deprivation (acute or chronic), fatigue (exhaustion), preexisting medical and mental conditions, and medication use can all affect the cognitive and behavioral performance of commercial aircraft pilots. This study evaluated the sleep habits of pilots and copilots flying short-haul flights in the Gulf region. Methods This cross-sectional study examined Airbus A320 pilots and copilots for one of Saudi Arabia's commercial airlines. Data such as age, sex, body mass index (BMI), employment position, work experience, flight hours, and rest time were collected. Each participant completed the Epworth Sleepiness Scale (ESS) for daytime sleepiness, the Pittsburgh Sleep Quality Index (PSQI), and the Fatigue Severity Index (FSI). Actigraphy equipment was used to perform objective sleep evaluations. Results Twenty-four participants were included. Actigraphy showed that 66.7% had an irregular sleep pattern and that 41.7% had poor sleep efficiency. We found that 12.5% had daytime sleepiness, 33% had poor sleep quality, and 29.2% had fatigue. We found a significant negative correlation between years of experience and time in bed; however, there was no significant difference in sleep time or sleep efficiency between pilots with different levels of experience. Conclusions We found that pilots and copilots are at risk of irregular sleep patterns, poor sleep efficiency, poor sleep quality, daytime sleepiness, and fatigue. This study emphasizes the need to instigate measures to minimize these risks.

Synergistic effect of carbon nanoparticles with mild salinity for improving chemical composition and antioxidant activities of radish sprouts.

The demand for healthy foods with high functional value has progressively increased. Carbon nanoparticles (CNPs) have a promising application in agriculture including the enhancement of plant growth. However, there are few studies on the interactive effects of CNPs and mild salinity on radish seed sprouting. To this end, the effect of radish seed priming with 80mM CNPs on biomass, anthocyanin, proline and polyamine metabolism, and antioxidant defense system under mild salinity growth condition (25 mM NaCl). The results indicated that seed nanopriming with CNPs along with mild salinity stress enhanced radish seed sprouting and its antioxidant capacity. Priming boosted the antioxidant capacity by increasing antioxidant metabolites such as (polyphenols, flavonoids, polyamines, anthocyanin, and proline). To understand the bases of these increases, precursors and key biosynthetic enzymes of anthocyanin [phenylalanine, cinnamic acid, coumaric acid, naringenin, phenylalanine ammonia lyase, chalcone synthase (CHS), cinnamate-4-hydroxylase (C4H) and 4-coumarate: CoA ligase (4CL)], proline [pyrroline-5-carboxylate synthase (P5CS), proline dehydrogenase (PRODH), Sucrose, Sucrose P synthase, invertase) and polyamines [putrescine, spermine, spermidine, total polyamines, arginine decarboxylase, orinthnine decarboxylase, S-adenosyl-L-methionine decarboxylase, spermidine synthase, spermine synthase] were analyzed. In conclusion, seed priming with CNPs has the potential to further stimulate mild salinity-induced bioactive compound accumulation in radish sprouts.

Evaluation of environmental and biological monitoring methods for toluene exposure assessment in paint industry.

The aim of this study was to assess the exposure to Toluene in paint industry and to evaluate the environmental and biological monitoring techniques for the assessment of occupational exposure to this aromatic hydrocarbon. In this study, personal active and passive air sampling for toluene measurements, blood and urine sampling respectively for B-Tol and HA or U-Tol analyses for eight workers from two paint and thinner production factories were collected during four successive working days. Correlations were analyzed between biological indicators and environmental toluene exposure levels. The concentration of Toluene measured in air samples ranged from 0.2 to 414.0 ppm (mean = 59.8 ppm), with high variability of atmospheric levels between activities and between days. No significant difference was found between airborne toluene concentrations measured by the two sampling methods. The correlation between air concentrations sampled by the diffusive sampling method and the biomarkers was the best for HA (r = 0.902, p < 0.01), followed by B-Tol (r = 0.820; p < 0.01), o-Cr (r = 0.691; p < 0.01) and U-Tol (r = 0.607; p < 0.05). The correlation was better between air concentrations and urinary metabolites HA and o-Cr for exposure levels higher than 50 ppm (r = 0.931; p < 0.01), and lower than 300 ppm (r = 0.827; p < 0.01), respectively. According to our results, workers in the studied industries are highly exposed to Toluene. Given the high correlation found between toluene concentrations in samples taken on dosimeters and those actively sampled on charcoal tubes, it may be assumed that both sampling methods are valuable. Despite the influencing factors, HA was found to be a reliable biological indicator for the monitoring of occupational exposure to toluene for high exposure levels. However, B-Tol seems to be an interesting alternative, since it is more specific and showed the best correlations with airborne toluene levels.

CO2 Enrichment Differentially Upregulated Sugar, Proline, and Polyamine Metabolism in Young and Old Leaves of Wheat and Sorghum to Mitigate Indium Oxide Nanoparticles Toxicity.

Soil contamination with indium oxide nanoparticles (In2O3-NPs) is a challenge for plant growth and productivity. Despite In2O3-NPs toxicity, their effects on plant growth and metabolism are largely unknown, particularly under future climate CO2 (eCO2). Therefore, the In2O3-NPs toxicity and stress mitigating impact of eCO2 in the young and old leaves of C3 (wheat) and C4 (sorghum) plants were investigated. Overall, In2O3-NPs significantly retard the biomass and photosynthetic machinery of all tested crops, particularly the young leaves of C3 plants. Consequently, In2O3-NPs altered C and N metabolism in C3 and C4 plants. On the other hand, eCO2 contrarily alleviated the hazardous effects of In2O3-NPs on growth and photosynthesis, especially in the young leaves of C4 plants. Increased photosynthesis consequently enhanced the soluble sugars' accumulation and metabolism (e.g., sucrose P synthase, cytosolic, and vacuolar invertase) in all stressed plants, but to a greater extent in C4 young leaves. High sugar availability also induced TCA organic and fatty acids' accumulation. This also provided a route for amino acids and polyamines biosynthesis, where a clear increase in proline biosynthetic enzymes [e.g., pyrroline-5-carboxylate synthetase (P5CS), ornithine aminotransferase (OAT), Pyrroline-5-carboxylate reductase (P5CR), pyrroline-5-carboxylate dehydrogenase (P5CDH), and proline dehydrogenase (PRODH)] and polyamine metabolic enzymes (e.g., spermine and spermidine synthases, ornithine decarboxylase, and adenosyl methionine decarboxylase) were mainly recorded in C4 young leaves. The observed increases in these metabolites involved in osmo- and redox-regulation to reduce In2O3-NPs induced oxidative damage. Overall, our study, for the first time, shed light on how eCO2 differentially mitigated In2O3-NPs stress in old and young leaves of different species groups under the threat of In2O3-NPs contamination.

Elevated CO2 Differentially Mitigated Oxidative Stress Induced by Indium Oxide Nanoparticles in Young and Old Leaves of C3 and C4 Crops.

Soil contamination with indium (In) oxide nanoparticles (In2O3-NPs) threatens plant growth and development. However, their toxicity in plants under ambient (aCO2) and elevated (eCO2) conditions is scarcely studied. To this end, this study was conducted to investigate In2O3-NPs toxicity in the young and old leaves of C3 (barley) and C4 (maize) plants and to understand the mechanisms underlying the stress mitigating impact of eCO2. Treatment of C3 and C4 plants with In2O3-NPs significantly reduced growth and photosynthesis, induced oxidative damage (H2O2, lipid peroxidation), and impaired P and Fe homeostasis, particularly in the young leaves of C4 plants. On the other hand, this phytotoxic hazard was mitigated by eCO2 which improved both C3 and C4 growth, decreased In accumulation and increased phosphorus (P) and iron (Fe) uptake, particularly in the young leaves of C4 plants. Moreover, the improved photosynthesis by eCO2 accordingly enhanced carbon availability under the challenge of In2O3-NPs that were directed to the elevated production of metabolites involved in antioxidant and detoxification systems. Our physiological and biochemical analyses implicated the role of the antioxidant defenses, including superoxide dismutase (SOD) in stress mitigation under eCO2. This was validated by studying the effect of In2O3-stress on a transgenic maize line (TG) constitutively overexpressing the AtFeSOD gene and its wild type (WT). Although it did not alter In accumulation, the TG plants showed improved growth and photosynthesis and reduced oxidative damage. Overall, this work demonstrated that C3 was more sensitive to In2O3-NPs stress; however, C4 plants were more responsive to eCO2. Moreover, it demonstrated the role of SOD in determining the hazardous effect of In2O3-NPs.

Effect of Elevated CO2 on Seed Yield, Essential Oil Metabolism, Nutritive Value, and Biological Activity of Pimpinella anisum L. Accessions at Different Seed Maturity Stages.

Besides the lack of studies regarding applying elevated CO2 (eCO2) as a strategy to improve the chemical composition of anise (Pimpinella anisum L.) seeds, studies on its interaction with seed developmental stages and origin are very limited. The seed yield, chemical composition, and biological activity of 6 aniseed accessions (Egypt, Tunisia, Syria, Turkey, Yemen, and Morocco) were investigated during three developmental stages (immature, premature, and mature) under control and elevated CO2 conditions. Mature seeds from all aniseed accessions had significantly higher (p < 0.05) dry weight (DW) percentages than premature and immature seeds. The highest DW percentages were recorded in Egypt and Morocco accessions. Seed maturation increased nutrients and antioxidant metabolites in most eCO2-treated accessions. In contrast, essential oils were decreased by seed maturation, while eCO2 reversed this effect. Essential oil-related precursors (e.g., phenylalanine) and enzyme activities (3-Deoxy-d-arabino-heptulosonate-7-phosphate synthase (DAHPS) and O-methyltransferase) decreased with seed maturity. However, high CO2 reduced this impact and further induced the other essential oil-related precursors (shikimic and cinnamic acids). Consequently, eCO2 provoked changes in the antioxidant and hypocholesterolemic activities of aniseeds, particularly at mature stages. Overall, eCO2 application, as an efficient way to improve aniseed growth, essential oil metabolism, and chemical composition, was affected by seed maturation and origin. Future studies of eCO2-treated aniseeds as a nutraceutical and pharmaceutical product are suggested.

Prevalence of Obstructive Sleep Apnea Among Saudi Pilots.

PURPOSE: To evaluate the presence of obstructive sleep apnea (OSA), using home sleep testing in pilots and first officers in Saudi-based airlines. This will allow for proper diagnosis and management of OSA in that group which can help in minimizing any possible aviation accidents related to sleep disturbances secondary to OSA. MATERIALS AND METHODS: This is a cross-sectional study conducted through Saudi-based aviation among pilots and first officers who were in service, active, and flying short- to medium-haul flights. Forty-one participants met the inclusion criteria. However, 39 out of 41 completed the study questionnaires (Berlin questionnaire, Epworth sleepiness scale, Pittsburgh sleep quality index (PSQI), Fatigue severity scale (FSS), Visual analog fatigue scale (VAFS), and Patient health questionnaire (PHQ9), along with home sleep testing. RESULTS: Sixty-nine percent of the study population had OSA by home sleep testing. Majority of which had mild OSA (64%) and 5% had moderate and severe OSA (2.5% each). Results of different questionnaires showed one-third of the participants had insomnia, 33.3% of the participants had severe fatigue, excessive daytime sleepiness was found in 23.1% of the participants, and 10.3% had moderate depression, while 25.6% were classified as having mild depression symptoms. CONCLUSION: Sleep apnea is prevalent among the studied Saudi-based airline pilots and first officers. Screening for workers of this high-risk occupation needs to be considered. Fatigue, depression, and insomnia can be secondary consequences of sleep apnea and should be assessed and treated early.

Sleep Disorders Among Commercial Airline Pilots.

BACKGROUND: Over the next 20 yr, international market expansion will necessitate the production of new commercial airplanes and the recruitment of additional crewmembers and technicians. Research has proven that fatigue and lack of sleep are risk factors for impaired cognitive performance and human error. Pilots frequently report fatigue to their employers, which may be related to sleep disturbance. Airline pilots, in particular, often experience circadian desynchronization and other types of sleep disorders. Shift workers have been observed to be at higher risk of fatigue that affects their performance and alertness. In Saudi Arabia, sleep disorders among airline pilots are understudied and underreported. The primary objective of this study was to screen for and determine the risk of sleep disorders, fatigue, and depression among pilots.METHODS: A cross-sectional epidemiological study with national commercial pilots was conducted from March 2019 to March 2020 using validated questionnaires to screen for the risk of sleep disorders, fatigue, and depression.RESULTS: In total, 344 pilots participated in the study. Half the sample was at risk for insomnia and fatigue. Older and more experienced pilots were less likely to suffer impaired sleep quality, insomnia, sleepiness, fatigue, and depression. In total, 59 (17.2%) pilots were at high risk for sleep apnea.CONCLUSION: The current study found that pilots were at risk of developing sleep disorders. A more robust and objective assessment is warranted for screening.Alzehairi A, Alhejaili F, Wali S, Al Qassas I, Balkhyour M, Pandi-Perumal SR. Sleep disorders among commercial airline pilots. Aerosp Med Hum Perform. 2021; 92(12):937-944.

Occupational accidents and injuries in construction industry in Jeddah city.

In Saudi Arabia, the construction industry has been growing remarkably during the past several years. However, the most hazardous worksites in the country may be found in this industry. This study identified the causes of accidents and injuries in the construction industry among 300 workers in Jeddah City, situated on the coast of the Red Sea. Results from the questionnaire showed that the major cause of accidents and injuries is the lack of awareness about occupational safety and lack of experience among the workers (>82%); and the most common type of accidents and injuries that occur in the construction industry, are workers falling from a height (>80%), and electrical shock (>60%). Recommendations to prevent accidents and injuries in this industry are provided in this paper.

Occupational exposure and respiratory health of workers at small scale industries.

Certain occupations like welding, painting, and vehicle repairing are associated with regular exposure to dust, exhausts, fuels, fumes, PM, and vapors of welding, solvents, and paint. Many studies have proved a reduction in lung functions due to exposure to these agents. The present study aims to assess and compare respiratory symptoms and pulmonary functions among exposed and non-exposed persons as well as suggests controls respectively. A cross-sectional case study was carried out among small scale industry workers having matched demographic and anthropometric parameters. Medical Research Council (MRC) questionnaire and Micro Direct computerized automated spirometer were used for recording respiratory ailments and pulmonary function tests (PFT) respectively. The percentages of mechanics, welders and painters were 40.9, 31.8, and 27.3 respectively. The highest reported respiratory symptom was chest tightness and whistling among exposed (22.7%) and unexposed (10%). Among study exposed cases, the occupational exposure was found as often (22.7%), sometimes (68.2%) and never (9.1%) while the reported use of airway protection (masks) was very low. Overall respiratory health of the exposed versus controls was reported as excellent (54.5% vs 73.4%), good (27.3% vs 23.3%) and average (18.2% vs 3.3%) respectively. The exposed group on contrary to control one has decreased mean values for FEV1 (3.12 vs 3.50), FVC (4.12 vs 4.43), FEV1/ FVC % (79.60 vs 80.79) and PEF (414.77 vs 523.16). The present study reveals that exposed workers are at increased risk of developing respiratory symptoms and decreased pulmonary functions as compared to unexposed. Such exposure research studies are instrumental in health status evaluation of workers. However, this area has been neglected by the researchers in Saudi Arabia. It is, thus, strongly recommended to carry out prospective studies to substantiate the study results including large sample size, background pollutants concentrations and biological monitoring. Control strategies should be adopted to reduce the vapor concentration in the ambient air, protect and promote respiratory health of workers.

Assessment of personal protective equipment use and occupational exposures in small industries in Jeddah: Health implications for workers.

Small-scale industries account for a large proportion of jobs and play a vital role in most countries' economic growth and prosperity. Due to the very low use of personal protective equipment (PPEs), employees are exposed to numerous physical, chemical, and accidental hazards in small-scale industries. PPEs are very effective in minimizing occupational injuries, accidents, and other hazards which otherwise result in substantial manpower and financial losses. The study objective was to assess the availability and use of PPEs as well as self-reported occupational exposures among workers in surveyed small industries in Jeddah. The study involved 102 workers from 28 small-scale industries (vehicle repair, welding, and paint). A survey was conducted to gather data of socio-demographic characteristics, self-reported occupational exposures, and frequency of PPEs used by workers. The occupational exposures (never exposed, sometimes exposed and always exposed) were reported in percentages including; noise exposure (19.6, 73.5 and 6.9%); dust/smoke exposure (9.8, 69.6 and 20.6%); vapors/fumes exposure (11.8, 60.8 and 27.5%); and direct sunlight (43.1, 56.9 and 0%), respectively. The reported use of different PPEs in descending order was; knee joints mats (50%), welding shields (50%), safety glasses (33.3%), gloves (27.5%), face masks (26.5%), safety shoes (10.8%) and earplugs/ muffs (8.8%). On the basis of this study findings, hand hygiene and general OSH awareness like interventions can be developed which will help in minimizing workplace exposures among small-scale industry workers.

Trends in occupational injuries and diseases among Saudi and non-Saudi insured workers.

BACKGROUND: The ongoing industrial and infrastructural development in Saudi Arabia carries a high risk of occupational injuries/diseases. AIMS: To compare trends in occupational injuries and diseases among Saudi and non-Saudi insured workers. METHODS: We used the index values method and slope (S) calculation to analyse the occupational injuries/diseases trends from data in the annual statistical reports published by the General Organization for Social Insurance between 2004 and 2014. Data for 10 565 993 (18.5%) Saudi insured workers (SIWs) and 46 402 079 (81.5%) non-Saudi insured workers (NSIWs) and 896 627 occupational injuries/diseases were analysed. RESULTS: The distribution of incidences of occupational injuries/diseases among NSIWs (93.5%) was 14 times higher than that of SIWs (6.5%). Occupational injuries/diseases were more likely to increase among NSIWs than SIWs, particularly in the construction, trade, financing and real estate economic activities, and engineering, technicians and service workers occupations. There was a general decreasing trend in occupational injuries/diseases until 2013. CONCLUSIONS: Non-Saudi insured workers were at high risk of occupational injuries/diseases, therefore, implementation of an effective injury prevention programme is required.

Evaluation of full-facepiece respirator fit on fire fighters in the municipality of Jeddah, Saudi Arabia.

The purpose of this study was to assess the effect of personal variables on the fit of the respirators used by firefighters and workers in highly polluted environments. However, resistance from many plants managers was met to conduct the study on their workers. Therefore, we were forced to limit the study on firefighters who were found very cooperative. Forty volunteer firefighters from different departments participated in the study. They were subjected to a daily leak rate measurement using a Control Negative Pressure (CNP) fit tester for five consecutive days. Two types of respirators were used for each volunteer: the Drager type and the MSA. At the end of the study, the association between face shape and presence of beard with the respirator leak rates was investigated. A significant difference in the leak rate was detected between the two types of respirators used, with the Drager respirator having higher leak rates. The presence of a beard increased dramatically the leak rate whatever the face shape was. The oval shape was the best fitting to the respirators, followed by the rounded and finally the rectangular face. The study recommends that personal variables like face shape must be taken into consideration and fit testing must be carried out periodically, to specify the respirator that best fits each firefighter. Having beard must be absolutely prohibited, since it can be life threatening in environmental dangerous conditions such those encountered during extinguishing fires and overhaul situations.

Total fume and metal concentrations during welding in selected factories in Jeddah, Saudi Arabia.

Welding is a major industrial process used for joining metals. Occupational exposure to welding fumes is a serious occupational health problem all over the world. The degree of risk to welder's health from fumes depends on composition, concentration, and the length of exposure. The aim of this study was to investigate workers' welding fume exposure levels in some industries in Jeddah, Saudi Arabia. In each factory, the air in the breathing zone within 0.5 m from welders was sampled during 8-hour shifts. Total particulates, manganese, copper, and molybdenum concentrations of welding fumes were determined. Mean values of eight-hour average particulate concentrations measured during welding at the welders breathing zone were 6.3 mg/m(3) (Factory 1), 5.3 mg/m(3) (Factory 2), 11.3 mg/m(3) (Factory 3), 6.8 mg/m(3) (Factory 4), 4.7 mg/m(3) (Factory 5), and 3.0 mg/m(3) (Factory 6). Mean values of airborne manganese, copper, and molybdenum levels measured during welding were in the range of 0.010 mg/m(3)-0.477 mg/m(3), 0.001 mg/m(3)-0.080 mg/m(3) and 0.001 mg/m(3)-0.058 mg/m(3) respectively. Mean values of calculated equivalent exposure values were: 1.50 (Factory 1), 1.56 (Factory 2), 5.14 (Factory 3), 2.21 (Factory 4), 2.89 (Factory 5), and 1.20 (Factory 6). The welders in factories 1, 2, 3, and 4 were exposed to welding fume concentration above the SASO limit value, which may increase the risk of respiratory health problems.