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Assessment of Activity Concentration of Radionuclides in Sediment from Oil Producing Communities of Delta State, nigeria

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Journal of Environmental Protection 2015年第6期6卷 640-650页

作者： caroline nihinlola iwet.n Ibiyinka Agboola Fuwape Adeseye Muyiwa Arogunjo Ganiyu Obor Physics Department Federal University of Technology Akure Nigeria Biochemistry Department Federal University of Technology Akure Nigeria

Activity concentrations of twenty-six (26) samples of sediment collected from rivers from eleven (11) oil-producing communities and two (2) non-oil producing communities in Delta state of nigeria were studied. Hyper Purity Germanium (HPGe) Detector was used for counting and detection of radionuclide content of all samples. Results of the samples analysed showed that the radioactivity concentrations of K40, Th232 and U238 in the sediment samples from oil-producing areas range from 32.47 Bq·kg-1 to 525.1 Bq·kg-1 with an average of 302.15 Bq·kg-1, 6.31 Bq·kg-1 to 19.33 Bq·kg-1 with an average of 11.66 Bq·kg-1, and 4.45 Bq·kg-1 to 18.69 Bq·kg-1 with an average of 8.66 Bq·kg-1 respectively. Activity concentrations at the control site ranged from 3.15 Bq·kg-1 to 4.80 Bq·kg-1, 2.27 Bq·kg-1 to 4.18 Bq·kg-1 and 1.15 Bq·kg-1 to 1.76 Bq·kg-1 for K40, Th232 and U238. These values are within the world average;natural radioactivity mapping of the study area is carried out using the Surfer software. Statistical analysis of the results showed that there is a significant difference between the radionuclide concentrations of the sediment samples from rivers in the oil producing site compared to results from non-oil producing communities, except for one of the oil producing site samples (Idumuesah) which has values that are close to those from the control sites for K40. The values of the radiological assessment indices obtained were observed to be within the permissible maximum values;hence the radiation hazard at study areas are negligible. However, concentration values of studied radionuclide at the oil-producing study areas were observed to be higher than values from the non-oil producing sites in most cases. It could therefore be reported that the operations of the oil companies in Delta state of nigeria may have contributed to the high radioactivity level of the river sediments. Although the concentration at the time of this study poses no risk, further industrial activities in t

关键词： Sediment natural Radioactivity TEnORM HPGe Detector

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Long-term changes in the plant ecology of an African savanna landscape and the implications for ecosystem theory and conservation management

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Ecological Processes 2021年第1期10卷 213-224页

作者： David Western Victor n.Mose David Maitumo caroline Mburu African Conservation Centre P.O.Box 15289-00509NairobiKeny

Background:Studies of the African savannas have used national parks to test ecological theories of natural ecosystems,including equilibrium,non-equilibrium,complex adaptive systems,and the role of top-down and bottom-up physical and biotic *** such studies have excluded the impact of pastoralists in shaping grassland ecosystems and,over the last half century,the growing human impact on the world’s *** mounting human impact calls for selecting indicators and integrated monitoring methods able to track ecosystem changes and the role of natural and human *** study draws on five decades of monitoring the Amboseli landscape in southern Kenya to document the declining role of natural agencies in shaping plant ecology with rising human ***:We show that plant diversity and productivity have declined,biomass turnover has increased in response to a downsizing of mean plant size,and that ecological resilience has declined with the rising probability of extreme shortfalls in pasture *** signature of rainfall and physical agencies in driving ecosystem properties has decreased sharply with growing human *** compare the Amboseli findings to the long-term studies of Kruger and Serengeti national parks to show that the human influence,whether by design or default,is increasingly shaping the ecology of savanna *** look at the findings in the larger perspective of human impact on African grasslands and the world rangelands,in general,and discuss the implications for ecosystem theory and conservation policy and ***:The Amboseli study shows the value of using long-term integrated ecological monitoring to track the spatial and temporal changes in the species composition,structure,and function of rangeland ecosystems and the role of natural and human agencies in the process of *** study echoes the widespread changes underway across African savannas and world’s rangelands,concluding that some level

关键词： Savannas Plants Human dominance Macroecology Conservation

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On the Stability of Racing Sailing Boats with Foils

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Chinese Annals of Mathematics,Series B 2018年第3期39卷 427-450页

作者： Philippe DESTUYnDER caroline FABRE Département d'ingénierie Mathématique Laboratoire M2N Conservatoire National des Arts et Métiers 292rue saint Martin75003 ParisFrance Laboratoire de Mathématiques d'Orsay Univ.Paris-SudCNRSUniversitéParis-Saclay 91405 OrsayFrance

The development of foils for racing boats has changed the strategy of sailing. Recently, the America＇s cup held in San Francisco, has been the theatre of a tragicomic history due to the foils. During the last round, the new-Zealand boat was winning by 8 to 1 against the defender USA. The winner is the first with 9 victories. USA team understood suddenly （may be） how to use the control of the pitching of the inain foils by adjusting the rake in order to stabilize the ship. And USA won by 9 victories against 8 to the challenger nZ. The goal in this paper is to point out few aspects which could be taken into account in order to improve this mysterious control law which is known as the key of the victory of the USA team. There are certainly many reasons and in particular the cleverness of the sailors and of all the engineering team behind this project. But it appears interesting to have a mathematical discussion, even if it is a partial one, on the mechanical behaviour of these extraordinary sailing boats. The nunlerical exanlples given here are not the true ones. They have just been invented in order to explain the theoretical developments concerning three points： The possibility of tacking on the foils for sailing upwind, the nature of foiling instabilities, if there are, when the boat is flying and the control laws.

关键词： Hydrodynamics of foils Mathematical analysis Stability

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A programmable microfluidic platform to monitor calcium dynamics in microglia during inflammation

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Microsystems & nanoengineering 2024年第4期10卷 285-296页

作者： Adam Shebindu Durga Kaveti Linda Umutoni Gia Kirk Michael D.Burton caroline n.Jones Department of Bioengineering University of Texas at DallasRichardsonTX 75080USA Department of Biomedical Engineering UT Southwestern Medical CenterDallasTX 75390USA Department of neuroscience University of Texas at DallasRichardsonTX 75080USA

neuroinflammation is characterized by the elevation of cytokines and adenosine triphosphate(ATP),which in turn activates *** immunoregulatory molecules typically form gradients in vivo,which significantly influence microglial behaviors such as increasing calcium signaling,migration,phagocytosis,and cytokine *** microglial calcium signaling in the context of inflammation holds the potential for developing precise therapeutic strategies for neurological ***,the current calcium imaging systems are technically challenging to operate,necessitate large volumes of expensive reagents and cells,and model immunoregulatory molecules as uniform concentrations,failing to accurately replicate the in vivo *** this study,we introduce a novel calcium monitoring micro-total analysis system(CAM-μTAS)designed to quantify calcium dynamics in microglia(BV2 cells)within defined cytokine *** programmable pneumatically actuated lifting gate microvalve arrays and a Quake valve,CAM-μTAS delivers cytokine gradients to microglia,mimicking *** device automates sample handling and cell culture,enabling rapid media changes in just 1.5 s,thus streamlining the experimental *** analyzing BV2 calcium transient latency to peak,we demonstrate locationdependent microglial activation patterns based on cytokine and ATP gradients,offering insights contrasting those of non-gradient-based perfusion *** harnessing advancements in microsystem technology to quantify calcium dynamics,we can construct simplified human models of neurological disorders,unravel the intricate mechanisms of cell-cell signaling,and conduct robust evaluations of novel therapeutics.

关键词： lifting dynamics offering

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High temperature X-ray diffraction study of the formation of na_(2)Ti_(3)O_(7) from a mixture of sodium carbonate and titanium oxide

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Journal of Energy Chemistry 2022年第2期31卷 210-218页

作者： caroline Piffet Bénédicte Vertruyen Frédéric Hatert Rudi Cloots Frédéric Boschini Abdelfattah Mahmoud GREEnMAT CESAM Research UnitChemistry DepartmentUniversity of Liège4000 LiègeBelgium Laboratory of Mineralogy Geology Research UnitUniversity of Liège4000 LiègeBelgium

na2Ti3O7 has attracted much attention in the field of anode materials for na-ion batteries thanks to its non-toxicity and very low working potential of 0.3 V vs na0/na+.Building a clearer picture of its formation from cheap na_(2)CO_(3) and TiO_(2) starting materials is therefore of obvious ***,we report new insights from an in-situ high temperature X-ray diffraction study conducted from room temperature to 800°C,complemented by ex-situ *** were thereby able to position the previously reported na_(4)Ti_(5)O_(12) and na_(2)Ti_(6)O_(13) intermediate phases in a reaction scheme involving three successive steps and temperature *** and/or broadening of a subset of the na_(2)Ti_(6)O_(13) reflections suggested a combination of intra-layer disorder with the well-established ordering of successive *** in-situ study was carried out on reproducible mixtures of na_(2)CO_(3) and TiO_(2) in 1:3 molar ratio prepared by spraydrying of mixed aqueous ***-phase na_(2)Ti_(3)O_(7) was obtained after only 8 h at 800°C in air,instead of a minimum of 20 h for a conventional solid-state route using the same *** analysis revealed~15 mm diameter granules made up from rectangular rods of a fewmm length presenting electrochemical properties in line with *** the absence of grinding or formation of intimate composites with conductive carbon,the specific capacity of 137 m Ah/g at C/5 decreased at higher rates.

关键词： Formation mechanism High temperature XRD na_(2)Ti_(3)O_(7) Spray-drying synthesis na-ion batteries

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InTEGRATED DESIGn COnSIDERATIOnS FOR SOLAR COMMUnITIES

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Journal of Green Building 2015年第2期10卷 134-156页

作者： caroline Hachem-Vermette Faculty of Environmental Design Professional Faculties 3170 University of Calgary2500 University Drive NWCalgary AB T2N 1N4

This paper presents design considerations for an integrated design of solar commu-nities highlighting the interactive nature of various design parameters to improve the energy performance of these *** considerations are illus-trated through practical design examples of different neighborhood scenarios and individual buildings,based on extensive studies and analysis of energy performance of a wide spectrum of buildings and *** examples fall under two general categories-design at the neighborhood level,and design at the individ-ual building *** design is illustrated by examples of homogeneous residential neighborhoods consisting of 2-storied housing units and of a mixed-rise *** of individual buildings focuses primarily on design of the envelope-consisting of roof and façades-for maximizing energy generation poten-tial,as a function of height and relative position to adjacent *** addition to examples of application of the design considerations,the paper outlines the process of design of solar communities and the role of simulations in the design process.

关键词： Integrated Design Process Solar Potential Passive solar design Building integrated photovoltaic Solar neighbourhood design

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Spawning ascent durations of pelagic spawning reef fishes

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Current Zoology 2012年第1期58卷 95-102页

作者： Habrun, caroline A. Sancho, Gorka College of Charleston Department of Biology Grice Marine Laboratory 205 Fort Johnson Road Charleston SC 29412 USA

Predation risks have been hypothesized to influence spawning behaviors of coral reef fishes that broadcast gametes pelagically. The duration of spawning ascents of 13 species were measured from video footage at a single spawning site for mul- tiple coral reef fishes to investigate ff this behavior was influenced by varying risks of predation. Fishes that spawned in pairs had as- cents of longer duration than group-spawning species. Duration of spawning ascents did not vary between fishes spawning at daytime and dusk, nor between group-spawning species with specific anti-predatory morphological adaptations. These results indicate that risk of predation may not significantly influence the duration of spawning ascents of pair spawning reef fishes at our study site, while group-spawning behaviors are influenced by predation. Avoidance of egg predation by benthic organisms and female mate choice are more likely to influence the pelagic spawning behaviors of all fishes observed [Current Zoology 58 （1）： 95-102, 2012].

关键词： Reef fishes Behavior Spawning Predation Mate selection

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Impact of microbial self-induced anaerobiosis fermentation(SIAF)on coffee quality

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Food Bioscience 2022年第3期47卷 421-430页

作者： Marcela caroline Batista da Mota nádia nara Batista Disney Ribeiro Dias Rosane Freitas Schwan Department of Biology Federal University of LavrasLavrasMGBrazil Food Science Department Federal University of LavrasLavrasMGBrazil

The fermentation of natural(nC)and pulped coffee(PC)was performed with a conventional method(platform)and under self-induced anaerobic fermentation(SIAF).Of the 12 samples analyzed during the fermentation process,the highest temperature was obtained by the SIAF method(30.5℃ for nC and 29.67℃ for PC)with 87 h of *** compounds(36 samples)were evaluated by high-performance liquid *** in the SIAF method contributed to the maximum amount of citric acid(2.534 mg/g)in pulped coffee and acetic acid(6.04 mg/g)and lactic acid(2.533 mg/g)in *** was the primary chemical class detected,followed by ketones and *** coffees(12 samples)were evaluated five times and classified as specialty coffees(>80 points)following Specialty Coffee Association(SCA)*** pulped coffee processed by the SIAF method showed a 2.83-point increase in the sensory score compared to the conventional ***,the SIAF method is accessible to producers,contributes to coffees with differentiated sensory profiles,and increases beverage quality.

关键词： Bioreactor Fermentative process Specialty coffee Anaerobic conditions natural processing

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A comparison of the relative efficiency of ICSI and extended culture with epididymal sperm versus testicular sperm in patients with obstructive azoospermia

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Asian Journal of Andrology 2020年第2期22卷 222-226页

作者： Scott J Morin Brent M Hanson caroline R Juneau Shelby A neal Jessica n Landis Richard T Scott Jr James M Hotaling Reproductive Medicine Associates of new Jersey 140 Allen RoadBasking RidgeNJ 07920USA Division of Reproductive Endocrinology and Infertility Department of Obstetrics and GynecologySidney Kimmel Medical College at Thomas Jefferson University833 Chestnut StreetPhiladelphiaPA 19107USA Foundation for Embryonic Competence 140 Allen RoadBasking RidgeNJ 07920USA Division of Urology Department of SurgeryUniversity of Utah School of Medicine30 N 1900 ESalt Lake CityUT 84132USA Department of Obstetrics and Gynecology University of Utah School of Medicine30 N 1900 ESalt Lake CityUT 84132USA.An abbreviated version of this manuscript was published and presented as an abstract at the American Society for Reproductive Medicine(ASRM)2017 Scientific Congress.

This is a retrospective cohort study comparing blastocyst transfer outcomes following intracytoplasmic sperm injection utilizing epididymal versus testicular sperm for men with obstructive *** cases at a single center between 2012 and 2016 were *** approach was selected at the surgeon’s discretion and included microepididymal sperm aspiration or testicular sperm *** culture was exclusively utilized prior to *** primary outcome was live birth *** outcomes included fertilization rate,blastulation rate,euploidy rate,and implantation rate.A mixed effects model was ***-six microepididymal sperm aspiration cases and 93 testicular sperm extraction cases were *** live birth rate was equivalent(48.6%vs 50.5%,P=0.77).However,on mixed effects model,epididymal sperm resulted in a greater likelihood of fertilization(adjusted OR:1.37,95%CI:1.05–1.81,P=0.02)and produced a higher blastulation rate(adjusted OR:1.41,95%CI:1.1–1.85,P=0.01).As a result,the epididymal sperm group had more supernumerary blastocysts available(4.3 vs 3,Pno *** rates were no different through the first transfer ***,intracytoplasmic sperm injection following microepididymal sperm aspiration resulted in a greater number of usable blastocysts per ***,the true benefit of epididymal sperm may only be demonstrated via a comparison of cumulative pregnancy rates after multiple transfers from one cohort.

关键词： azoospermia intracytoplasmic sperm injection male infertility testicular sperm extraction

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Impact of on-range choice feeding with black soldier fly larvae(Hermetia illucens)on flock performance,egg quality,and range use of free-range laying hens

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Animal nutrition 2018年第4期4卷 452-460页

作者： Isabelle Ruhnke Camille normant Dana L.M.Campbell Zafar Iqbal caroline Lee Geoff n.Hinch Julie Roberts Faculty of Science AgricultureBusiness and LawSchool of Environmental and Rural ScienceUniversity of New EnglandArmidaleNSW 2351Australia Institut Polytechnique LaSalle Beauvais 60000 BeauvaisFrance F.D.McMaster Laboratory Commonwealth Scientific and Industrial Research Organisation(CSIRO)ArmidaleNSW 2350Australia

Semi-intensive free-range farm systems are common in Australia, and these systems frequently practise on-range feeding. The objective of this study was to investigate the benefit of on-range choice feeding on flock performance, egg quality, and range use of free-range laying hens using black soldier fly larvae(Hermetia illucens, BSF). A total of 160 mature ISA brown laying hens, previously determined to range daily, were allocated to a control group(control) or a treatment group(BSF) with various replicates depending on the parameter investigated. All hens were fed ad libitum indoors with a wheat-soy based diet formulated according to breed requirements. Black soldier fly hens were offered dried BSF larvae ad libitum on the range. Body weight, feed intake, BSF intake, egg production, feed conversion ratio, internal and external egg quality parameters, and individual range use using radio-frequency identification(RFID)technology was evaluated. Black soldier fly hens consumed on average 15 ± 1.7 g BSF larvae/hen per *** were no differences between BSF and control hens for any of the performance parameters obtained(P > 0.05). Egg weight, shell weight, and shell thickness of eggs from BSF hens were significantly lower(P = 0.003, P = 0.001, and P = 0.004, respectively) than those of eggs from control hens. Egg yolk colour was significantly paler in eggs from BSF hens(P no significant ranging differences between the BSF and control hens were observed(P > 0.05) except for BSF hens showing longer total maximum time for a single visit to the range(P = 0.011). In conclusion, the average intake of BSF larvae indicated a good level of acceptance. Feed formulation should be adjusted for the intake of the choice fed source. The impact of choice-feeding on range use was minor.

关键词： Behaviour Chicken Insect protein nutrition Poultry Radio-frequency identification

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