Concerns have developed for the possible negative health effects of radiofrequency electromagnetic field (RF-EMF) exposure to children's brains. The purpose of this longitudinal study was to ...investigate the association between mobile phone use and symptoms of Attention Deficit Hyperactivity Disorder (ADHD) considering the modifying effect of lead exposure.
A total of 2,422 children at 27 elementary schools in 10 Korean cities were examined and followed up 2 years later. Parents or guardians were administered a questionnaire including the Korean version of the ADHD rating scale and questions about mobile phone use, as well as socio-demographic factors. The ADHD symptom risk for mobile phone use was estimated at two time points using logistic regression and combined over 2 years using the generalized estimating equation model with repeatedly measured variables of mobile phone use, blood lead, and ADHD symptoms, adjusted for covariates.
The ADHD symptom risk associated with mobile phone use for voice calls but the association was limited to children exposed to relatively high lead.
The results suggest that simultaneous exposure to lead and RF from mobile phone use was associated with increased ADHD symptom risk, although possible reverse causality could not be ruled out.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Loss of skeletal muscle mass and strength has recently become a hot research topic with the extension of life span and an increasingly sedentary lifestyle in modern society. Maintenance of skeletal ...muscle mass is considered an essential determinant of muscle strength and function. Myokines are cytokines synthesized and released by myocytes during muscular contractions. They are implicated in autocrine regulation of metabolism in the muscle as well as in the paracrine/endocrine regulation of other tissues and organs including adipose tissue, the liver, and the brain through their receptors. Till date, secretome analysis of human myocyte culture medium has revealed over 600 myokines. In this review article, we summarize our current knowledge of major identified and characterized myokines focusing on their biological activity and function, particularly in muscle mass and function.
•Flexural capacity of SFRC with variance in concrete strength and fiber content were evaluated.•First peak and post-cracking strength, and energy absorption capacity were discussed.•Effects of ...concrete strength and fiber content in equivalent strength ratio were evaluated.•Ultimate capacity of floor slabs was evaluated considering concrete strength and fiber content.
An experimental study was performed to examine the effects of concrete strength and fiber content ratio on the flexural capacity of steel fiber-reinforced concrete. Three fiber volume fractions, 0.25, 0.375, and 0.5%, and three concrete compressive strengths, 25, 35, and 45MPa, were designed for the experiments. The stress and deflection relationship, first peak and post-cracking strength, and energy absorption capacity were evaluated with respect to the variance in the fiber volume fraction and concrete strength. The results showed that the equivalent flexural strength ratio, which is determined from the first peak strength and energy absorption capacity, increased with the increase in the fiber volume fraction but decreased with the increase in the concrete strength. Furthermore, the effects of the concrete strength and fiber content ratio are discussed in a steel fiber-reinforced concrete floor slab. The ultimate flexural capacity also required a consideration of the influence of the content ratio of steel fiber as well as the strength of cement composite matrix.
Summary
Although Roux‐en‐Y gastric bypass (RYGB) and sleeve gastrectomy (SG) are the most prevalent bariatric surgical procedures, high‐level evidence is scarce regarding the assessment of ...postoperative nutritional risk in RYGB versus SG. Therefore, we performed a systematic review and meta‐analysis to compare the risk of anemia and related micronutrient deficiencies after RYGB and SG. We analyzed 10 randomized controlled trials that compared RYGB and SG with reported incidence of postoperative anemia and/or anemia‐related micronutrient deficiencies (iron, vitamin B12, or folate). There were no significant differences in the risk of postoperative anemia (moderate level of evidence), iron deficiency (high level of evidence), or folate deficiency (moderate level of evidence). Patients undergoing RYGB had a higher risk of postoperative vitamin B12 deficiency than those undergoing SG (relative risk, 1.86; 95% confidence interval, 1.15–3.02; p = 0.012; high level of evidence). Our findings imply that patients undergoing RYGB require more stringent vitamin B12 supplementation and surveillance than those undergoing SG. Additionally, our results may aid patients with high concern for anemia and related micronutrient deficiencies in making informed decisions regarding surgical methods based on nutritional risk.
•Simultaneous treatment using HC was proposed to enhance the lipid yield.•Optimal conditions for lipid extraction from Nannochloropsis salina were determined.•HC was energy-efficient compared with ...autoclaving and ultrasonication.
Simultaneous treatment (combining with cell disruption and lipid extraction) using hydrodynamic cavitation (HC) was applied to Nannochloropsis salina to demonstrate a simple and integrated way to produce oil from wet microalgae. A high lipid yield from the HC (25.9–99.0%) was observed compared with autoclave (16.2–66.5%) and ultrasonication (5.4–26.9%) in terms of the specific energy input (500–10,000kJ/kg). The optimal conditions for the simultaneous treatment were established using a statistical approach. The efficiency of the simultaneous method was also demonstrated by comparing each separate treatment. The maximum lipid yield (predicted: 45.9% and experimental: 45.5%) was obtained using 0.89% sulfuric acid with a cavitation number of 1.17 for a reaction time of 25.05min via response surface methodology. Considering its comparable extractability, energy-efficiency, and potential for scale-up, HC may be a promising method to achieve industrial-scale microalgae operation.
This study explores the major driving forces behind the dynamic pattern of the college wage premium in Korea since the 1980s, using the demand and supply framework. We find that movements in the ...college wage premium are mainly explained by expansion of the relative supply of college graduates and an increase in the relative demand for high‐skilled labour due to trade with China. We also find that the substitutability in Korea between college and non‐college‐educated workers is higher, with an elasticity of approximately 3.5–4.1 than that in advanced economies. The counterfactual analyses demonstrate that with a lower substitution elasticity or smaller trade volume with China, Korea might have witnessed a sharp decline in the college wage premium.
Liver cirrhosis (LC) can be caused by obesity, alcohol consumption, viral infection, and autoimmune disease. Early diagnosis and management of LC is important for patient quality of life. ...Non-invasive diagnostic methods are useful for predicting the current status and mortality risk of LC. The purpose of this study is to identify relevant diagnostic factors measured in routine laboratory test of alcohol-related liver cirrhosis (ALC) patients.
This study analyzed data from 127 patients with ALC, including their laboratory test results and clinical information, including coagulation parameters, hematologic parameters, and biochemical parameters. These data were used to compare the performance of the prediction models from three machine learning algorithms including K-nearest neighbor (KNN), support vector machine (SVM), and random forest (RF).
Higher Model for End-stage Liver Disease (MELD) score were associated with prothrombin time (PT) and D-dimer. Logistic and multiple linear regression analyses revealed significant factors predicting mortality in the MELD group. Machine learning approaches were used to predict death in ALC patients using some laboratory parameters associated with mortality. The prediction model based on SVM exhibited better prediction performance than others.
PT and D-dimer were the factors that were most strongly associated with 90-day mortality, and machine learning methods can create prediction models with good predictive power.
•Several characteristics of crimped SMA fiber such as tensile behavior, stress recovery and residual stress is investigated.•Pullout resistance of crimped SMA fibers compared with those of straight ...SMA fiber and paddled SMA fiber.•Pullout resistance of crimped SMA fiber is a function of wave geometry, number of waves embedded and yield strength of fiber.
This paper assesses the bond strength of crimped fibers manufactured by a cold-drawn SMA wire using a continuous method. Several pullout tests are conducted to study bond strength and crack-closing ability of crimped SMA wire. Before and after SMA heating, the pullout force–displacement relationships of crimped fibers are compared with different types of end-shapes, namely, straight and paddled end, to measure the bond strength of these fibers in cementitious composite material. The cold drawn fiber with more than 4% area reduction ratio due to cold drawing work should be used for producing crimped fibers to overcome the stretching effect of indentation by heating. The paddled fibers show almost twice energy dissipation capacity than the crimped fibers, while secant stiffnesses of the crimped fibers are larger by 20% on the maximum than those of the paddled fibers. Crack-closing ability of crimped fibers may be evaluated when the stretching effect at the bent parts due to thermal expansion are compared with recovery effect of prestrain due to shape memory effect. The experimental data reveals the efficiency and applicability of the crimped SMA fibers in contrast to other end-shape SMA fibers provided by discontinuous methods.
Lithium‐mediated reduction of dinitrogen is a promising method to evade electron‐stealing hydrogen evolution, a critical challenge which limits faradaic efficiency (FE) and thus hinders the success ...of traditional protic‐solvent‐based ammonia electro‐synthesis. A viable implementation of the lithium‐mediated pathway using lithium‐ion conducting glass ceramics involves i) lithium deposition, ii) nitridation, and iii) ammonia formation. Ammonia was successfully synthesized from molecular nitrogen and water, yielding a maximum FE of 52.3 %. With an ammonia synthesis rate comparable to previously reported approaches, the fairly high FE demonstrates the possibility of using this nitrogen fixation strategy as a substitute for firmly established, yet exceedingly complicated and expensive technology, and in so doing represents a next‐generation energy storage system.
The fix is N: The strong reducing power of lithium allows facile dinitrogen dissociation to be used in an ammonia electro‐synthesis process with extraordinary faradaic efficiency. This straightforward three‐step process represents a promising nitrogen cycle for next‐generation energy storage systems.
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