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Open Journal of Ecology 2022年第11期12卷 718-732页

作者： raymond charles Oluwole Daniel Makinde Monica Kung’aro Department of Mathematics University of Dodoma Dodoma Tanzania Faculty of Military Science Stellenbosch University Cape Town South Africa

Interaction between prey and predator species is a complex and non-linear process. Understanding various phenomena in the dynamics of prey-predator systems is vital to both mathematical ecology and conservation biology. Mathematical models on prey-predator systems have been the hot sport providing important information regarding the interactions of prey and predator species in various ecosystems. In this paper, a review of the available mathematical models on prey-predator systems was done. Our aim was to assess their structure, behaviour, available control strategies, population involved and their ability in predicting the future behaviour of the ecosystems. We observed diversities in the reviewed mathematical models, some model incorporated factors such as drought, harvesting and prey refuge as the factors that affect ecosystems, some ignored the contribution of environmental variations while others considered the variable carrying capacity. Most of the models reviewed have not considered the contribution of diseases and seasonal weather variation in the dynamics of prey predator systems. Some of the reviewed models do not match the real situation in most modelled ecosystems. Thus, to avoid unreliable results, this review reveals the need to incorporate seasonal weather variations and diseases in the dynamics of prey predator systems of Serengeti ecosystem.

关键词： Prey Predator Weather Variation Disease Serengeti Ecosystem

Asbestos Exposure during Gasket Removal from Aircraft Engine

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Occupational Diseases and Environmental Medicine 2024年第2期12卷 59-67页

作者： charles L. Blake Kevin M. Guth raymond D. Harbison Apex Companies Marietta USA Center for Environmental and Occupational Risk Analysis and Management College of Public Health University of South Florida Tampa USA

We have previously evaluated asbestos exposure associated with various maintenance procedures on light aircraft. The purpose of this study was to evaluate asbestos exposure during engine maintenance on light aircraft. This test was designed to evaluate the potential for asbestos exposure to mechanics and others who remove asbestos-containing engine gaskets from reciprocating style aircraft engines. Utilized in this test was an air cooled, horizontally opposed, aviation gasoline burning engine, assembled during 1986 and operated intermittently up into 2015, having accumulated 1680 hours run time. Nearly 75% of the asbestos-containing gaskets installed during 1986 were still in place at the time of testing. Chrysotile asbestos contents of such gaskets ranged from 55% to 60% by area, for those of sheet style and 5% by area, for the spiral wound metal/asbestos style. Despite the levels of effort required to effect gasket removals, the professional aircraft mechanic was not exposed to airborne asbestos fibers at the lower limits of sampling and analytical detection achieved;all of which were substantially less than the current Occupational Safety and Health Administration Permissible Exposure Limits for asbestos. The results of this testing indicate an absence of gasket related asbestos exposure risk to mechanics who work with light aircraft engines, including those having asbestos-containing gaskets. These results are consistent with the findings of Mlyarek and Van Orden who studied the asbestos exposure risk occasioned during overhaul of larger radial style reciprocating aircraft engines [1].

关键词： Asbestos Exposure Gaskets Aircraft Engine Friction Materials

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情有时比血浓

少年文摘 2004年第11期 40-41页

作者： charles raymond 杨柳岸

那天凯莱出现时,善良的杰克不忍心打破凯莱对亲情的渴望,而自己也好像多了一个可爱的女儿,所以希望这个秘密不被凯莱知道。

关键词：凯莱马里兰州母亲洗衣房医院先天性心脏病化验结果墨西哥玉米血型中学

High efficacy of chlorfenapyr-based net Interceptor■G2 against pyrethroid-resistant malaria vectors from Cameroon

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Infectious Diseases of Poverty 2023年第4期12卷 1-16页

作者： Magellan Tchouakui Riccado F.Thiomela Elysee Nchoutpouen Benjamin D.Menze Cyrille Ndo Dorothy Achu raymond N.Tabue Flobert Njiokou Ateba Joel charles S.Wondji Centre for Research in Infectious Diseases(CRID) P.O.Box 13501YaoundéCameroon Department of Animal Biology and Physiology Faculty of ScienceUniversity of Yaoundé1P.O.Box 812YaoundéCameroon Department of Biological Sciences Faculty of Medicine and Pharmaceutical SciencesUniversity of DoualaP.O.Box 24157DoualaCameroon Ministry of Public Health National Malaria Control ProgrammeP.O.Box 14386YaoundeCameroon Department of Vector Biology Liverpool School of Tropical MedicinePembroke PlaceLiverpoolL35QAUK International Institute of Tropical Agriculture(IITA) P.O.Box 2008YaoundéCameroon

Background The increasing reports of resistance to pyrethroid insecticides associated with reduced efficacy of pyrethroid-only interventions highlight the urgency of introducing new non-pyrethroid-only control ***,we investigated the performance of piperonyl-butoxide(PBO)-pyrethroid[Permanet 3.0(P3.0)]and dual active ingredients(AI)nets[Interceptor G2(IG2):containing pyrethroids and chlorfenapyr and Royal Guard(RG):containing pyrethroids and pyriproxyfen]compared to pyrethroid-only net Royal Sentry(RS)against pyrethroid-resistant malaria vectors in *** The efficacy of these tools was firstly evaluated onAnopheles gambiae *** funestus *** Gounougou,Mibellon,Mangoum,Nkolondom,and Elende using cone/tunnel *** addition,experimental hut trials(EHT)were performed to evaluate the performance of unwashed and 20 times washed nets in semi-field ***,pyrethroid-resistant markers were genotyped in dead vs alive,blood-fed vs unfed mosquitoes after exposure to the nets to evaluate the impact of these markers on net *** XLSTAT software was used to calculate the various entomological outcomes and the Chi-square test was used to compare the efficacy of various *** odds ratio and Fisher exact test were then used to establish the statistical significance of any association between insecticide resistance markers and bed net *** Interceptor G2 was the most effective net against wild *** followed by Permanet *** EHT,this net induced up to 87.8%mortality[95%confidence interval(CI):83.5-92.1%)and 55.6%(95%CI:48.5-62.7%)after 20 washes whilst unwashed pyrethroid-only net(Royal Sentry)killed just 18.2%(95%CI:13.4-22.9%)of *** unwashed Permanet 3.0 killed up to 53.8%(95%CI:44.3-63.4%)of field-resistant mosquitoes and 47.2%(95%CI:37.7-56.7%)when washed 20 times,and the Royal Guard 13.2%(95%CI:9.0-17.3%)for unwashed net and 8.5%(95%CI:5.7-11.4%)for t

关键词： Malaria Anopheles Insecticide resistance Dual active ingredient nets Interceptor G2

Strain control of layer-resolved negative capacitance in superlattices

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npj Computational Materials 2020年第1期6卷 127-130页

作者： raymond Walter Sergey Prosandeev charles Paillard L.Bellaiche Department of Physics and Institute for Nanoscience and Engineering University of ArkansasFayettevilleAR 72701USA Department of Mathematical Sciences University of ArkansasFayettevilleAR 72701USA Identity Engineering Kinesso LLCConwayAR 72032USA Institute of Physics and Physics Department of Southern Federal University Rostov-na-Donu 344090Russia Laboratoire Structures Propriétés et Modélisation des SolidesCentraleSupélecUMR CNRS 8580UniversitéParis-Saclay91190 Gif-sur-YvetteFrance

Negative capacitance in BaTiO_(3)/SrTiO_(3) superlattices is investigated by Monte Carlo simulations in an atomistic effective Hamiltonian model,using fluctuation formulas for responses to the local macroscopic field that incorporates depolarizing *** show that epitaxial strain can tune the negative capacitance of the BaTiO_(3) ferroelectric layer and the overall capacitance of the *** addition,we predict and explain an original switching of the negative capacitance from the BaTiO3 layer to the SrTiO_(3) layer at low temperatures for intermediate strains.

关键词： capacitance layer resolved

Assessment of Asbestos Exposure Associated with a Brake Grinder

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Occupational Diseases and Environmental Medicine 2023年第3期11卷 137-142页

作者： charles L. Blake Kevin M. Guth raymond D. Harbison Apex Companies Marietta GA USA College of Public Health University of South Florida Center for Environmental and Occupational Risk Analysis and Management Tampa Florida USA

The wear patterns for drum-style automotive brakes tend to enlarge internal drum diameters. Such enlargement is most profound when used brake drums are machined to restore the metal friction surfaces. Specialized arc grinding machinery has been used to match replacement shoe-style brake friction materials to enlarged drums. The process of arc grinding removes friction material, thereby producing dust. When organic-style friction materials contained asbestos, use of arc grinding machinery posed an asbestos fiber exposure risk to operators and proximate personnel. The manufacturers of arc grinding machinery have incorporated local exhaust ventilation systems designed to capture and remove this dust at the point of grinding contact and propel this dust into collection bags or other systems. This research was designed to evaluate the dust capture and retention characteristics of a specific arc grinder product, when used to custom grind asbestos-containing brake friction materials. A Bear Model 1420 automotive brake shoe arc grinder was the subject of this study. During two separate but consecutive test sessions, newly relined sets of shoe-style automobile brake friction materials were precision ground. Both area and personal air samples were collected throughout each testing session. This work took place within a closed and unventilated metal building, with total interior volume of 2500 m3. Collected air samples were analyzed using phase contrast microscopy (PCM) and transmission electron microscopy (TEM). The results of analysis using PCM for personal samples (n = 6) ranged from <0.044 to 0.055 fibers per cc (f/cc) (mean 0.05). Follow-up analysis of these personal samples using TEM indicated asbestos-adjusted PCM exposures ranging from <0.0074 to 0.055 f/cc (mean ≤ 0.041). Area air samples, taken at distances ranging from 1.5 to 9 meters from the arc grinder (n = 12), showed asbestos-adjusted PCM concentrations ranging from <0.0075 to 0.041 f/cc (mean ≤ 0.01

关键词： Asbestos Exposure Brakes Arc Grinder Friction Materials

Aircraft Brake Dust Dispersion (Airwash) Testing

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Occupational Diseases and Environmental Medicine 2022年第4期10卷 255-261页

作者： charles L. Blake Robert E. Bailey Kevin M. Guth raymond D. Harbison Apex Companies Marietta GA USA ESi Colorado Springs CO USA Center for Environmental and Occupational Risk Analysis and Management College of Public Health University of South Florida Tampa FL USA

Prior industrial hygiene research involving wheel brake changing on a light general aviation aircraft has shown negligible potential for asbestos fiber exposure to mechanics that perform such work. This is despite the use of organic-style brake friction pads that contained asbestos. It has been otherwise established that chrysotile asbestos is largely degraded to a non-crystalline, amorphous substance by the heat and mechanical shear forces inherent to the braking process. However, trace (<1.0%) quantities of chrysotile have been found in brake wear dust. Disc-style brakes, the types used on aircraft, are of open design, such that wear dust is typically dispersed into the ambient air during and after brake application. For fixed-gear aircraft, the brake assemblies are also subject to substantial air velocities while the aircraft is in flight. This research was undertaken to measure and characterize the airflows experienced by aircraft wheel assemblies during takeoff, cruise, and landing maneuvers. No wear (brake) dust was observed at any point during the study.

关键词： Aircraft Brakes Asbestos Airwash

Relationship between acute hypercarbia and hyperkalaemia during surgery

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World Journal of Clinical Cases 2019年第22期7卷 3711-3717页

作者： Laurence Weinberg Amelia Russell Lois Mackley charles Dunnachie Joshua Meyerov Chong Tan Michael Li raymond Hu Dharshi Karalapillai Department of Anaesthesia Austin HealthMelbourneVictoria 3084Australia Department of Intensive Care Austin HealthMelbourneVictoria 3084Australia Melbourne Medical School University of MelbourneVictoria 3010Australia

BACKGROUND The relationship between hyperkalaemia and metabolic acidosis is well described in the critical care setting;however,the relationship between acute respiratory acidosis and plasma potassium concentration is less well *** a controlled model of increasing levels of hypercarbia,we tested the hypothesis of whether increasing levels of hypercarbia are associated with changes in plasma potassium *** To determine whether increasing levels of hypercarbia are associated with changes in plasma potassium *** We performed a post-hoc study examining changes in serum potassium in 24 patients who received increased levels of hypercarbia during cardiac *** blood gases and plasma concentrations of potassium were measured at baseline,3 min prior to,and then every 3 min for 15 min during the intervention of *** primary endpoint was the absolute change in serum K+at 15 min compared to the baseline K+*** following secondary endpoints were evaluated:(1)The association between CO2 and serum K+concentration;and(2)The correlation between plasma pH and serum K+*** During the intervention,PaCO2 increased from 43.6 mmHg(95%CI:40.1 to 47.1)at pre-intervention to 83.9 mmHg(95%CI:78.0 to 89.8)at 15 min after intervention;P<*** mean(SD)serum potassium increased from 4.16(0.35)mmol/L at baseline to 4.28(0.33)mmol/L at 15 min(effect size 0.09 mol/L;P=0.22).There was no significant correlation between PaCO2 and potassium(Pearson’s coefficient 0.06;95%CI:-0.09 to 0.21)or between pH and potassium(Pearson’s coefficient-0.07;95%CI:-0.22 to 0.09).CONCLUSION Acute hypercarbia and subsequent respiratory acidaemia were not associated with hyperkalaemia in patients undergoing major surgery.

关键词： Anaesthesia Intensive care Biochemistry Surgery

Application of solvent pH under pressurized conditions using accelerated solvent extraction and green solvents to extract phytonutrients from wild berries

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Food Bioscience 2022年第3期47卷 463-473页

作者： Amanda Rajakaruna charles F.Manful Ibrahim M.Abu-Reidah Amber L.Critch Natalia P.Vidal Thu H.Pham Mumtaz Cheema raymond Thomas School of Science and the Environment Grenfell CampusMemorial University of NewfoundlandCorner BrookA2H 5G4Canada The Functional Foods Sensory Laboratory Grenfell CampusMemorial University of NewfoundlandCorner BrookA2H 5G4Canada

Berry fruits are known as“superfoods”due to health benefits associated with the high content of bioactive compounds or *** extraction solvents are fundamentally volatile compounds acquired from non-renewable resources,i.e petroleum-based solvents are presumed to be harmful to both human health and the *** to the new emphasis on environmental and safety protections and the development of green chemistry,finding alternative solvents to replace the organic ones has recently become a major ***,there is a great interest in the scientific community to develop a suitable green approach to allow the extraction and recovery of the bioactive phytonutrients from berry sources for applications in improving human health and *** this study,the phytonutrient composition of three popular wild berries:blueberry(Vaccinium angustifolium),partridgeberry(Vaccinium vitis-idaea L.)and Rosehipberry(Rosa canina),were evaluated following extraction using biphasic green solvents at pH 2.5,7.0,and 11.5 under pressurized conditions using Accelerated Solvent Extraction(ASE)*** total phenolic content and composition,antioxidant activity,vitamin and mineral content of the berry extracts were evaluated using Folin-Ciocalteu assay,Ferric Reducing Antioxidant Power Assay(FRAP),Ultra-High-pressure Liquid Chromatography-Mass Spectrometry(UHPLC-MS)and inductively coupled plasma-mass spectrometry(ICP-MS),*** highest total antioxidant activity(p≤0.05)and phenolic content were observed in rosehip berry followed by blueberry and partridgeberry in the hydroethanolic extracts at pH ***,the highest extraction efficiency of total fat-soluble vitamins(FSV)and total B vitamins were also observed in the hydroethanolic extract at pH *** in rosehipberry and partridgeberry the highest vitamin C content was observed in hydroethanolic extract at pH 11.5,whereas in blueberry it was observed in the pH 2.5 hydroethanolic extract.I

关键词： Wild berries Accelerated solvent extraction(ASE) Hydroethanolic extracts Alkaline pH Phytonutrients

Power Stripping of Asbestos-Containing Insulation from Electrical Cable

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Occupational Diseases and Environmental Medicine 2019年第3期7卷 65-74页

作者： charles L. Blake Giffe T. Johnson raymond D. Harbison Bureau Veritas Kennesaw GA USA Center for Environmental and Occupational Risk Analysis and Management College of Public Health University of South Florida Tampa FL USA

Efforts to recycle copper from electrical conductors have led to the development of specialized machines, which automatically remove insulating covers from wires and cable products. In the past, certain wire and cable products were insulated using chrysotile asbestos. This research was undertaken to determine the asbestos fiber exposure risks associated with power stripping machinery to remove asbestos-containing insulation materials from electrical wire or cable. A Rigby Machinery, Inc., Model 4H electric powered wire/cable insulation stripping machine was acquired along with approximately 42 m of asbestos insulated cable. During two separate, but nearly identical, test sessions, a laborer used the wire stripper to remove the asbestos-containing insulation from the subject cable. This work took place within a closed metal building with a total interior volume of 2500 m3. Industrial hygiene personal and area air samples were collected for airborne fibers throughout all wire stripping periods. Collected air samples were analyzed using phase contract microscopy (PCM) and transmission microscopy (TEM). The results of analysis using PCM for personal samples (n = 3) taken during periods of continuous cable stripping activity showed test period airborne fiber exposures ranging from 0.034 to 0.068 (mean 0.056 f/cc). Follow-up analysis of these personal samples using TEM indicated asbestos adjusted PCM exposures ranging from 0.017 to 0.045 (mean 0.033 f/cc). Area air samples taken at distances ranging from 2 to 9 meters from the wire stripper (n = 16) showed asbestos adjusted PCM concentrations ranging from less than 0.0001 to 0.041 f/cc (mean 0.007 f/cc). The process of power stripping asbestos-containing insulation from electrical wires and cables can cause exposure to airborne asbestos fibers. However, the levels of such exposure are not expected to exceed the current occupational exposure limits for asbestos of 0.1 f/cc as an 8-hr TWA or 1.0 f/cc averaged over a 30-minu

关键词： Asbestos Exposure Insulating Covers Power Stripping Electrical Wire Chrysotile Asbestos Asbestos Fibers Asbestos-Related Disease Asbestos-Containing Material