Health care for pesticide applicators in a locust eradication campaign in Kuwait (1988-1989)

Pesticide applicators in the Plant Protection Department of the Agriculture Affairs and Fish Resources Authority are monitored regularly by the Occupational Health Section of the Ministry of Health. The aim is to protect them from the adverse effects of pesticides and to prevent acute poisoning by removing from exposure those who have low cholinesterase (ChE) activity levels or low white blood cell counts. Thirty-eight workers routinely examined in July 1988 were reexamined at the onset of the locust invasion in Kuwait in November 1988; also examined were 36 farmers recruited for the first time to fight locusts and a matched control group of 38 firefighters. After 2 to 3 months, when the locust invasion decreased markedly and pesticide spraying nearly stopped, the exposed workers were reexamined. The pesticides used to control locusts were five organophosphates and one organochlorine (lindane). Sixty percent of normal for red blood cell (RBC) ChE activity and 50% of normal for plasma ChE activity were used as threshold levels for removing workers from continued exposure to ChE-inhibiting pesticides. The different reactions of study groups during the locust control period are described, including results from tests of pulmonary function, RBC and plasma ChE activity, and nerve conduction velocity.     

The energy saving effects of complex heat-integrated distillation configurations

The distillation of a ternary BTX mixture was studied to evaluate three potential energy saving methods: optimal configuration strucluring, heat integration and heat pumping. Ten heuristics, in two categories, were induced and arranged in order of priority. Separation-technique heuristics: (1) Favor heat flux exchange between units by direct stream contact (thermal coupling). (2) Favor separations with initial splits between extremes in volatility (prefractionation). (3) Favor heat integration if flexibility and operability are satisfactory. (4) Favor operation under lower pressures if the cost involved is reasonable. (5) Favor heat pumping with a product stream as the working medium. Separation-system heuristics: (1) Favor the PET configuration. (2) Favor the PF configuration if various feeds are anticipated. (3) Favor the SS configuration for very low concentrations of the most or least volatile components. (4) Favor the R heat integration form. (5) Favor the OHP heat pumping form.     

Comparative Study of Power Saving and Delay in LTE DRX,Directional-DRX and Hybrid-Directional DRX

With integration of advanced long term evolution networks (LTE networks) in mobile technology, 5G networks are introduced due to broadband spectrum extension which requires higher power consumption. Discontinuous reception (DRX) sleep mode mechanism is provided to accommodate lower power consumption of user equipment terminals (UE_s). For mmWave directional communication air interface in LTE between UE and LTE eNB, UE performs beam searching and alignment with LTE eNB (4G base station) after every short/long DRX cycle during ON duration. Dual connectivity of UE to both LTE eNB and NR NodeB (5G New RAN base station) is a hybrid-directional system. This allows us to propose a sleep mode mechanism which is called hybrid directional-DRX (HD-DRX). In HD-DRX, UE performs beam searching and alignment with NR NodeB during ON duration only if data packet intimation. A semi-Markov chain process is introduced to describe UE state transition. Depending on this chain, power saving factor and average delay are calculated. HD-DRX power saving as compared to LTE DRX and Directional-DRX (D-DRX) is conducted. Due to different beam searching procedure, another comparison of average delay is assigned between D-DRX and HD-DRX. Data traffic model parameters are considered and numerical analysis is validated using MATLAB program simulations.     

Parental attitudes toward mouthguards

An 11-item, one-page questionnaire was mailed to 1800 parents chosen at random in the Henrico County, VA public school system. Parents were asked questions such as "who should be responsible for mouthguard wear?" "what sports should require mouthguards?" and "has [their] child ever sustained an oral or facial injury?" The parental responses indicate that mouthguard enforcement is the responsibility of both parents and coaches. Of the total injuries reported, 19% were sustained in basketball, 17% in baseball, and 11% in soccer. Despite these high injury rates, however, there was a lack of perceived need for mouthguard use in these sports. When asked which sports should require a mouthguard rule, the sports that generated the most responses were, in decreasing order, football, boxing, ice hockey, wrestling, field hockey, and karate. Parents were more likely to require mouthguards for their sons than daughters, and more likely to require them for their children who participated in a mandatory mouthguard sport, a contact sport, or who had been previously injured. The authors conclude that because parents view themselves as equally responsible as coaches for maintaining mouthguard use, both groups should be targeted and approached as a possible source for the recommendation of mandatory mouthguard rules in basketball, baseball, and soccer.     

Few-mode ring core fiber characteristics: temperature impact

Photonic Network Communications - In this paper, a novel fiber is proposed to support few linearly polarized (LP) modes, with the feature of a circular ring-shaped core filled by liquid. This fiber...     

Enhanced coyote optimizer-based cascaded load frequency controllers in multi-area power systems with renewable

Neural Computing and Applications - Recently, the renewable energy has been occupied a lot of attention around the world since it presents cheap and sustainable energy. Consequently, its presence...     

Liquid—solid mass transfer at vertical screens in bubble columns

The effect of gas sparging on the rate of mass transfer at a vertical single screen was studied by an electrochemical technique which involved measuring the limiting current of the cathodic reduction of potassium ferricyanide. Variables studied were screen characteristics, physical properties of the solution and gas superficial velocity. Screen characteristics, e. g., mesh number and wire diameter were found to have little effect on the rate of mass transfer. The data at different screens were correlated in terms of the superficial gas velocity by the equation St Sc_0.5 = 0.095 (Re Fr)^?0.272, where St is Stanton number, Sc is Schmidt number, Re is Reynolds number and Fr is Froude number. Comparison of the present data with previous results obtained with different transfer geometries has shown that screens produce higher rates of mass transfer than other geometries. The importance of the present work to catalytic and electrochemical reactor design was noted.     

Acidity of sulfated zirconia as studied by FTIR spectroscopy of adsorbed CO and NH3 as probe molecules

The acid properties of pure and sulfated zirconias were studied by FTIR spectroscopy of adsorbed CO and NH₃ as probe molecules. Whereas pure monoclinic zirconia shows only Lewis acidity, sulfation of tetragonal and monoclinic zirconia creates new bridging OH groups. Two types of Brønsted-acidic centers and two types of Lewis-acidic centers with enhanced acid strength were identified. A communication between the different types of Lewis-acidic sites and the related adsorbed sulfate molecules could be shown. The coordination of basic molecules such as CO onto Lewis-acid sites induces a decrease of the intrinsic Brønsted-acidity of the bridging OH groups. These effects are discussed on the basis of a model of the acidic centers that was previously proposed.On leave from Department of Chemistry, Faculty of Science, Minia University, El-Minia, Egypt.     

Dynamometer evaluation and engine wear characteristics of palm oil diesel emulsions

Dynamometer engine tests at steady-state conditions and a wear characteristics study were carried out on an indirect-injection diesel engine with palm oil diesel (POD) and its emulsions. The POD fuel was obtained in commercial form, and its emulsions were created by mixing POD fuel to contain 5 and 10% of water by volume. Variations in the engine’s performance characteristics were determined from the results of steady-state tests carried out at fifteen selected torque-speed matrix points of the engine’s performance map. The wear characteristics tests were performed by running the engine at half throttle setting for twenty hours for each fuel system. Then a desk-top comparison study was performed between the base-line fuel system of ordinary diesel (OD), POD, and its emulsions. Promising results have been obtained. Neither the lower cetane number of POD fuel nor its emulsification with water presented obstacles to the operation of the diesel engine during a series of steady-state engine tests and the twenty-hour endurance tests. Engine performance and fuel consumption for POD and its emulsions are comparable with those of OD fuel. Accumulations of wear metal debris in crank-case oil samples were lower with POD and its emulsions than with baseline OD fuel.     

Graft copolymerization of methyl methacrylate onto oil palm empty fruit bunch fiber using H2O2/Fe2+ as an initiator

Graft copolymerization of methyl methacrylate (MMA) onto oil palm empty fruit bunch fiber (OPEFB) was successfully carried out in aqueous medium using hydrogen peroxide as an initiator. Results from the investigation of the optimum conditions for grafting are presented. Maximum percentage of grafting was achieved when the amount of initiator, cocatalyst, and nitric acid were 5.877 × 10^?3 mol, 2.63 × 10^?4 mol, and 3.24 × 10^?3 mol, respectively. The optimum reaction temperature was 50°C and the reaction period was 120 min. The highest percentage of grafting and grafting efficiency were 220 and 47%, respectively, under optimum conditions. The grafted copolymer was characterized by FTIR spectroscopy and scanning electron microscopy. The presence of a band at 1730 cm^?1 provides strong evidence of grafting. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2233–2238, 2003