Effect of Computer Keyboard Slope on Upper Limb Postures at Sitting and Standing ComputerWorkstations : A Pilot Study

A user’s posture at a computer workstation, especially wrist posture, is determined by the keyboard angle. Most commercially available computer keyboards have a built-in positive slope that requires the user to extend their wrist approximately 20° when typing. The purpose of this study is to find the negative keyboard angles that minimize wrist extension for both sitting and standing workstations. In this study, we compared upper limb working postures, including those of the wrist, elbow and shoulder, at 5 different keyboard angles between −16° and +6° in sitting and standing postures. Based on our results, we can conclude that the optimal range of keyboard slope is from −4° to −12° in sitting posture and −8° to −12° in the standing posture in terms of minimum wrist extension, typing performance, and user preference. We also propose a universal keyboard support design as an attachment to currently available keyboards.

The Effect of Eight Weeks of Training on Positive and Negative Slopes with Royal Jelly Consumption on MGMT and ATPase Gene Expression Levels in the Hippocampus Tissue of Trimethyltin-Induced Alzheimer’s Rats

Background: Alzheimer’s disease (AD) is a common disease in the elderly that is associated with impaired metabolism and biology of the hippocampus. Although the role of exercise and natural antioxidants in improving the disease has been reported, the role of muscle contraction-related physical activity along with royal jelly (RJ) consumption is not yet well understood. Objectives: This study aimed to investigate the effect of eight weeks of training on positive slope (ETPS) and negative slope (ETNS) with royal jelly (RJ) consumption on O-6-methylguanine DNA methyltransferase (MGMT) and ATPase gene expression levels in the hippocampus tissue of trimethyltin (TMT)-induced AD rats. Methods: In this experimental trial, 36 male Sprague-Dawley AD rats (induced with 8 mg/kg TMT) were divided into (1) control + normal saline/royal jelly solvent) (Sh); (2) ETPS; (3) ETNS; (4) ETPS + RJ; (5) ETNS + RJ, and (6) RJ groups. Six rats were placed in the healthy control (HC) group. Then the training groups trained on ( + 15 and -15) slopes for eight weeks, five sessions per week, and each session lasted 60 minutes at a speed of 16 m/min. The royal jelly (RJ) groups received 100 mg/kg royal jelly per day by intraperitoneal injection. Results: ETNS, ETPS, ETPS + RJ, and ETNS + RJ increased MGMT gene expression (P ≥ 0.05). ETPS and ETPS + RJ also increased ATPase gene expression (P ≥ 0.05). However, RJ had no significant effect on increasing MGMT and ATPase gene expression in the hippocampus tissue of AD rats (P ≥ 0.05). Conclusions: It seems that the improvement of DNA damage markers and energy levels depends on the type of contraction. Although training on positive and negative slopes with royal jelly consumption has an interactive effect on DNA repair markers, training on a positive slope and royal jelly consumption has an interactive effect on ATPase gene expression.

Sensor less Control of Switched Reluctance Motor

Switched reluctance motor is considered for variable speed applications. It is a power device which can be manufactured easily and inexpensively and relatively high reliable. A sensor less control of SRM is proposed. Here, the communication of SRM is done without use of position detector. It is ensured that the switching of each phase winding takes place during positive slope of inductance profile. Simulation is carried out using MATLAB. A 6/4 SRM is used for this purpose.

Head-to-head comparison of (R)-[11C]verapamil and [18F]MC225 in non-human primates, tracers for measuring P-glycoprotein function

Purpose P-glycoprotein (P-gp) function is altered in several brain disorders; thus, it is of interest to monitor the P-gp function in vivo using PET. (R)-[11C]verapamil is considered the gold standard tracer to measure the P-gp function; however, it presents some drawbacks that limit its use. New P-gp tracers have been developed with improved properties, such as [18F]MC225. This study compares the characteristics of (R)-[11C]verapamil and [18F]MC225 in the same subjects. Methods Three non-human primates underwent 4 PET scans: 2 with (R)-[11C]verapamil and 2 with [18F]MC225, at baseline and after P-gp inhibition. The 30-min PET data were analyzed using 1-Tissue Compartment Model (1-TCM) and metabolite-corrected plasma as input function. Tracer kinetic parameters at baseline and after inhibition were compared. Regional differences and simplified methods to quantify the P-gp function were also assessed. Results At baseline, [18F]MC225 VT values were higher, and k2 values were lower than those of (R)-[11C]verapamil, whereas K1 values were not significantly different. After inhibition, VT values of the 2 tracers were similar; however, (R)-[11C]verapamil K1 and k2 values were higher than those of [18F]MC225. Significant regional differences between tracers were found at baseline, which disappeared after inhibition. The positive slope of the SUV-TAC was positively correlated to the K1 and VT of both tracers. Conclusion [18F]MC225 and (R)-[11C]verapamil show comparable sensitivity to measure the P-gp function in non-human primates. Moreover, this study highlights the 30-min VT as the best parameter to measure decreases in the P-gp function with both tracers. [18F]MC225 may become the first radiofluorinated tracer able to measure decreases and increases in the P-gp function due to its higher baseline VT.

Trend and Variability Analysis of Rainfall and Temperature Trends in Ilorin Metropolis, Kwara State, Nigeria

ABSTRACT Rainfall and temperature are the most important physical parameters that influence climate. This paper examines the trend and variability of rainfall and temperature of Ilorin township in Nigeria between2010- 2018, using standard statistical descriptors. Rainfall had an increasing trend (positive slope value of 5.30), moderate precipitation concentration index of 12.15 percent and extremely high degree of variability with a coefficient of variation ranging between 33.54 percent and 155.73 percent. Temperature also had a slight warming or increasing trend (positive slope value of 0.012) with minimal degree of variability of coefficient of variation between 5.49 percent and 7.31 percent. The oscillating structure of both rainfall and temperature anomalies further confirm yearly fluctuations as well as change in the distribution and characteristics. It is recommended that government and non-government agencies should formulate plans and policies that will accommodate changes in rainfall and temperature patterns to successfully manage the environment.

Longitudinal assessment of loss and gain of lung function in childhood asthma

Background: The Childhood Asthma Management Program study revealed that 25.7% of children with mild to moderate asthma exhibit a loss of lung function. The objective was to assess the trajectories of function by means of serial FEV1 in asthmatic children participating in out-of-hospital follow-up. Methods: A total of 295 children (199 boys) who had undergone at least 10 spirometry tests from the age of 8 were selected from a single-center open cohort. The annualized rate of change (slope) for prebronchodilator FEV1 (percent predicted) was estimated for each participant and three patterns were defined: significantly positive slope, significantly negative slope, and null slope (non-significant P-value in the Pearson test). The standard deviation (SD) of each individual slope was recorded as a variability criterion of FEV1. Results: The median (25th and 75th percentile) age at inclusion and the last visit was 8.5 (8.2, 9.3) and 15.4 (14.8, 16.0) years, respectively. Tracking of function (null slope) was observed in 68.8% of the children, while 27.8% showed a loss of function (negative slope) and 3.4% showed a gain in function (positive slope). The children characterized by loss of function depicted a better initial function and a lower FEV1 variability during their follow-up than children with tracking or gain of lung function. At the last visit, these children were characterized by a lower lung function than children with tracking or gain of lung function. Conclusion: Children with a better initial FEV1 value and less FEV1 variability are more prone to loss of lung function.

Polygenic Nature of Olivines from the Ultramafic Lamprophyres of the Terina Complex (Chadobets Upland, Siberian Platform) Based on Trace Element Composition, Crystalline, and Melt Inclusion Data

Olivine from the deep mantle-derived rocks, such as ultramafic lamprophyres, carries important information about the composition of the mantle source, the processes of mantle metasomatism, the origin of specific silicate-carbonate melts, as well as the composition and mechanisms of crystallization of these rocks. Textures and compositions of olivine from the carbonate-rich ultramafic lamprophyres (aillikites) of the Terina complex, along with their mineral and melt inclusions, exposed that olivines have different sources. Two populations of olivines were considered: macrocrysts (>1 mm) and groundmass olivines (<1 mm). Groundmass olivines are phenocrysts and characterized by weak variations in Mg# (84–86.5), a sharp increase in Ca and Ti contents, and a decrease in Ni and Cr from core to rim. They have higher concentrations of Li, Cu, Ti, and Na compared to macrocrysts. Among the macrocrysts, the following populations are observed: (1) high-Mg olivines (Mg# 89–91) with high Ni and low Ti contents, which are interpreted as xenocrysts from the slightly depleted lherzolite mantle; (2) high-Ca olivines (Mg# 84–88, CaO 0.13–0.21 wt %), which have patterns similar to groundmass olivines and are interpreted as cumulates of early portions of aillikite melt; (3) macrocrysts with wide variations in Mg# (73–88), low CaO contents (0.04–0.11 wt %), and positive slope in Ca vs. Al and negative slope in Ca vs. Mn, which are interpreted as disintegrated megacrysts from the Cr-poor megacryst suite. The megacryst suite could have been formed in the pre-trap period during the melting of the metasomatized subcontinental lithospheric mantle (SCLM). The aillikite melt evolution is traced by secondary melt inclusions in olivine macrocrysts: early phlogopite-diopside-calcite-apatite association, containing Ti-magnetite and ilmenite, is followed by an association with magnetite and sulfides (pyrrhotite and pentlandite); finally, at a late stage, inclusions with a predominance of Ca-Na-carbonates and sulfates and enriched in U, Th, Y, REEs, Sr, and Ba were captured.