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Effects of anthropogenic disturbances on natural regeneration and population structure of gum arabic tree (Acacia senegal)in the woodlands of Lake Baringo ecosystem, Kenya

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Journal of forestry Research 2017年第4期28卷 775-785页

作者： Stephen f. Omondi David W. Odee George O. Ongamo james I. Kanya Damase P. Khasa Kenya forestry Research Institute P.O. Box 2041200200 NairobiKenya School of Biological Sciences University of NairobiP. O. Box 30197-00100NairobiKenya Centre for forest Research and Institute for Systems andIntegrative Biology Universite′ LavalSainte-FoyQC G1V 0A6Canada

Despite the ecological and economic importance of Acacia senegal, little is known about the effects of anthropogenic disturbances on its natural regeneration patterns and population structure. We investigated the effects of these factors within the Lake Baringo woodland ecosystem. Data was collected from 60 plots of 20 m × 20 m systematically distributed in four A. senegal-dominated populations within the Lake Baringo woodland. Sample populations spanned a degradation gradient measured by a population disturbance index (PDI). Trees were measured for diameter at breast height (DBH) and categorized by growth stages: seedling, sapling and adult tree. Higher seedling and sapling densities were recorded in lightly than heavily disturbed populations, but only sapling density was significantly different between the two disturbance levels (P = 0.02). Lightly disturbed populations revealed a reversed J-shape size-class distribution (SCD) indicative of stable structure unlike the heavily disturbed populations. The quotient and permutation indices indicated unstable populations with episodic recruitment and mortality. Our study reveals that natural regeneration and population structure of A. senegal were affected majorly by selective harvesting and heavy browsing. Suitable management strategies to control livestock grazing and illegal tree harvesting within the woodland is required to promote conservation of the species genetic resources

关键词： Anthropogenic disturbance Population dynamics Renewal rate Selective harvesting Tropical woodland

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Why Hollywood Hates Business： Immanuel Kant＇s Role in Avatar.＂ Movie Reviewed by Adam Smith

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Journal of Philosophy Study 2013年第6期3卷 470-480页

作者： james f. Pontuso Hampden-Sydney College

One of cinematic science fiction＇s most popular plot lines is to imagine an invasion of earth by an advanced alien species. james Cameron＇s Avatar turns the tables on that premise. Humans attack a peaceful, less technologically sophisticated race in order to exploit their natural resources. Driving the assault is a mining company hell-bent on improving its bottom line. The villain of Avatar is not a person, but those people who seek profit. To put it starkly, business is evil. But why has the entertainment business cast business as a heavy？ Hollywood has now made Immanuel Kant as the director of moral sentiment. Not, of course, directly, but rather the ghostwriter of Hollywood＇s ideas about morality. The works of Kant are not discussed or debated in the public arena, but their principles have influenced the way people think about what is just and good. The ideas of Kant have filtered into the contemporary discourse and are one of the key ingredients in the national dialogue over what it means to be moral. The categorical imperative holds that an action is moral only if it is free from calculation of reward or gain. To be truly, moral people must abandon all practical considerations of need or desire; they must be directed by pure good will alone. Business people can never measure up to Kant＇s standard. They always make choices based on cost and benefit. Their businesses would quickly go bankrupt, if they made decisions on good will rather than interest. Kant＇s principles have raised the moral standard so high that even the common inclination to seek one＇s own benefit is looked on with some mistrust. In Kantian-influenced movies, business people have come to play the evil antagonist; they seek gain instead of the good. How would Adam Smith, the father of economic rationality, respond to popularized Kantian morality？

关键词： Smith Kant Hollywood

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Marx＇s Concept of Alienation： With a Brief Assessment

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Journal of Philosophy Study 2015年第1期5卷 1-15页

作者： james f. Pontuso Hampden-Sydney College

Since the collapse of Euro-Communism in 1989, the ideas of Marx have largely been discarded as little more than historical relics. There is a good reason for the neglect. The governments that Marxism spawns are among the most brutal in history. Equally condemnable for a philosopher who bases his theory on a science of historical development, most of Marx＇s key predictions turn out to be incorrect. What then is left of Marx＇s principles？ This paper argues that Marx is best understood as a critic of the injustice of industrial societies. Marx＇s essential critical concept is alienation. The paper presents the first complete analysis of Marx＇s treatment of alienation and offers a brief assessment of how this concept applies to our time.

关键词： Marx alienation postmodemor not to Marx

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Daily heart rate variability of Paralympic gold medallist swimmers： A 17-week investigation

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Journal of Sport and Health Science 2015年第4期4卷 371-376页

作者： rohan Edmonds Anthony Leicht Mark McKean Brendan Burkett School of Health and Sport Sciences University of the Sunshine Coast Sunshine Coast 4556 Australia College of Healthcare Sciences James -Cook University Townsville 4811 Australia

Objectives： Heart rate variability （HRV） can be a simple, non-invasive method of gauging cardiac autonomic nervous system fluctuations across periodised training workloads and taper in elite athlete populations. The purpose of these three case studies was to examine daily cardiac autonomic variations in Paralympic athletes leading in to the Paralympic games. Methods： Three Paralympie gold medallist swimmers were monitored daily for their resting HRV over a 17-week monitoring period leading up to the Paralympic games. Specific time- and frequency-domain measures, along with non-linear indices of HRV were calculated for all analyses. All HRV data were analysed individually using daily values, weekly average values, and average values for rest and training phases. Results： A significant difference in HRV was seen for all variables between athlete 1 and athletes 2 and 3 （amputee disabilities） during the entire monitoring period. Conclusion： Despite minimal long-term changes, both swimming classification and disability type significantly influence HRV during athlete monitoring. An increased understanding of individual responses to training, travel, and other outside influences affecting Paralympic athletes could potentially lead to improved management and monitoring of training workloads for enhanced nerformance.

关键词： Autonomic nervous system Cardiac modulation Disability Elite athlete Periodised training Testing

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The song remains the same： Juvenile Richardson＇s ground squirrels do not respond differentially to mother＇s or colony member＇s alarm calls

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Current Zoology 2012年第5期58卷 773-780页

作者： james f. HARE Kurtis J. WARKENTIN Department of Biological Sciences University of Manitoba Winnipeg MB Canada R3T 2N2 Department of Zoology Brandon University Brandon MB R7A 6A9

Alarm calls are emitted by Richardson＇s ground squirrels Urocitellus richardsonii in response to avian and terrestrial predators. Conspecifics detecting these calls respond with increased vigilance, promoting predator detection and evasion, but in doing so, lose time from foraging. That loss can be minimized if alarm call recipients discriminate among signalers, and weight their response accordingly. for juvenile ground squirrels, we predicted that the trade-off between foraging and vigilance could be optimized via selective response to alarm calls emitted by their own dam, and/or neighboring colony members over calls broad- cast by less familiar conspecifics. Alarm calls of adult female Richardson＇s ground squirrels were elicited in the field using a predator model and recorded on digital audio tape. free-living focal juveniles were subjected to playbacks of a call of their mother, and on a separate occasion a call from either another adult female from their own colony, or an adult female from another colony. Neither immediate postural responses and escape behavior, nor the duration of vigilance manifested by juveniles differed with exposure to alarm calls of the three adult female signaler types. Thus, juveniles did not respond preferentially to alarm calls emitted by their mothers or colony members, likely reflecting the high cost of ignoring alarm signals where receivers have had limited opportunity to establish past signaler reliability [Current Zoology 58 （5）： 773-780, 2012].

关键词： Alarm Signal Communication Maternal Call Recognition Signal Reliability Ground Squirrel Social Discrimination

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Magnitude of modulation of gene expression in aneuploid maize depends on the extent of genomic imbalance

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Journal of Genetics and Genomics 2020年第2期47卷 93-103页

作者： Adam f·Johnson Jie Hou Hua Yang Xiaowen Shi Chen Chen Md Soliman Islam Tieming Ji Jianlin Cheng james A·Birchler Institurte of Research and Development Duy Tan UniversityDa Nang50000Viet Nam Department of Electrical Engineering and Computer Science University of MissouriColumbiaMO65211USA Division of Biological Sciences University of MissouriColumbiaMO65211USA Department of Statistics University of MissouriColumbiaMO65211USA

Aneuploidy has profound effects on an organism,typically more so than polyploidy,and the basis of this contrast is not fully understood.A dosage series of the maize long arm of chromosome 1(1L)was used to compa re relative global gene expression in diffe rent types and degrees of aneuploidy to gain insights into how the magnitude of genomic imbalance as well as hypoploidy affects global gene *** previously available methods require a selective examination of specific genes,RNA sequencing provides a whole-genome view of gene expression in *** studies of global aneuploidy effects have concentrated on individual types of aneuploids because multiple dose aneuploidies of the same genomic region are difficult to produce in most model genetic *** genetic toolkit of maize allows the examination of multiple ploidies and 1-4 doses of chromosome ***,a detailed examination of expression changes both on the varied chromosome arms and elsewhere in the genome is possible,in both hypoploids and hyperploids,compared with euploid *** studies observed the inverse trans effect,in which genes not varied in DNA dosage were expressed in a negative relationship to the varied chromosomal *** response was also the major type of changes found globally in this *** genes varied in dosage showed proportional expression changes,though some were seen to be partly or fully dosage *** was also found that the effects of aneuploidy were progressive,with more severe aneuploids producing effects of greater magnitude.

关键词： Aneuploidy Polyploidy Inverse effect Gene regulation Dosage compensation Gene balance hypothesis

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Current state and prospect on the development of advanced nuclear fuel system materials:A review

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Materials Reports(Energy) 2021年第1期1卷 69-87页

作者： Di Yun Chenyang Lu Zhangjian Zhou Yingwei Wu Wenbo Liu Shaoqiang Guo Tan Shi james f.Stubbins School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an710049China School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Department of Nuclear Plasma and Radiological EngineeringUniversity of Illinois at Urbana-ChampaignUrbanaIL61801USA

The intricate balance between reactor economics and safety necessitates the emergence of new and advanced nuclear systems and,very importantly,advanced materials,which can overcome current shortcomings and bring about more economic nuclear systems with designed-in inherent safety *** advances will achieve greater safety and better nuclear reactor economics by reaching longer reactor lives with higher levels neutron irradiation,and by providing higher operation temperatures and resistance to more aggressive corrosive *** paper provides a review of the current state of research and development on innovative nuclear fuel materials design and development which have the potential of benefiting simultaneously reactor economics and *** discussion focuses on three areas of research:Accident-tolerant fuels(ATfs),Oxidation Dispersion Strengthened(ODS)steels and High Entropy Alloys(HEAs).The paper also gives a prospective description of future research activities on these materials.

关键词： Nuclear fuel materials Nuclear cladding materials Accident-tolerant fuel(ATf) Oxidation dispersion strengthened(ODS)steel High entropy alloy(HEA)

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An experimental study on pile scour mitigating measures under waves and currents

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Science China(Technological Sciences) 2015年第6期58卷 1031-1045页

作者： LIANG SenDong ZHANG YongLiang YANG james State Key Laboratory of Hydro-Science and Engineering Tsinghua University Hydraulic Engineering Royal Institute of Technology (KTH)

An experimental study has been carried out to investigate effects of four flow-altering scour countermeasures placed around a foundation pile under currents only as well as under coexisting waves and currents. The countermeasures are sacrificial piles, downstream bed sill, sleeve and slot in the pile. Their arrangements follow the suggested optimal configurations, with some of them slightly modified. In terms of the evolution of scour depth and bed topography around the pile, the scour countermeasures are evaluated, subjected to steady currents with or without irregular waves. A comparison between maximum scour depth with the countermeasures and one without the countermeasures demonstrates the efficiency of countermeasures. All the tested scour measures reduce the scour depth by 17.6%–42.6% under the action of currents only and 5.8%–24.0% under the combined action of both currents and waves. The results also show that it takes a shorter time for the scour depth to reach its equilibrium with the measures under either coexisting currents and waves or currents only than ones without the measures.

关键词： experimental study scour countermeasures waves currents foundation pile

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The integrated use of chemical insecticides and the entomopathogenic nematode, Steinemema carpocapsae （Nematoda： Steinernematidae）, for the control of sweetpotato whitefly, Bemisia tabaci （Hemiptera： Aleyrodidae）

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Insect Science 2008年第5期15卷 447-453页

作者： Andrew G. S. Cuthbertson james J. Mathers Phil Northing Anthony J. Prickett Keith f. A. Waiters Central Science Laboratory Sand Hutton York YO41 1LZ UK

The integration of chemical insecticides and infective juveniles of the entomopathogenic nematode Steinernema carpocapsae （Wesier）（Nematoda： Steinernematidae）, to control second instars of the sweetpotato whitefly, Bemisia tabaci Gennadius （Hemiptera： Aleyrodidae） was investigated. Using a sand bioassay, the effects of direct exposure of S. carpocapsae for 24 h to field rate dilutions of four insecticides （spiromesifen, thiacloprid, imidacloprid and pymetrozine） on infectivity to Galleria mellonella larvae were tested. Although all chemicals tested, except spiromesifen, produced acceptable nematode infectivity rates, they were all significantly less than the water control. The effect of insecticide treatment （dry residues of spiromesifen, thiacloprid and pymetrozine and soil drench of imidacloprid） on the efficacy of the nematode against B. tabaci was also investigated. Nematodes in combination with thiacloprid and spiromesifen gave higher B. tabaci mortality （86.5% and 94.3% respectively） compared to using nematodes alone （75.2%） on tomato plants. There was no significant difference in B. tabaci mortality when using the chemicals imidacloprid, pymetrozine and spiromesifen in conjunction with nematodes compared to using the chemicals alone. However, using thiacloprid in combination with the nematodes produced significantly higher B. tabaci mortality than using the chemical alone. The integration of S. carpocapsae and these chemical agents into current integrated pest management programmes for the control of B. tabaci is discussed.

关键词： entomopathogenic nematode infectivity insecticide residue pest management

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Nickel sulfate solution fluoride separation with hydrous zirconium oxide

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Tungsten 2024年第2期6卷 367-381页

作者： Elbert M.Nigri Ummul K.Sultana André L.A.Santos james W.Vaughan Sonia D.f.Rocha Department of Mining Engineering Federal University of Minas GeraisBelo Horizonte 31270-901Brazil School of Chemical Engineering University of QueenslandSt Lucia 4072Australia

fluoride is an impurity in nickel sulfate production,which is required for electric vehicle *** zirconium oxide(HZO)was evaluated for removing fl uoride from nickel sulfate *** fluoride removal occurred at pH value 4 and optimal pH value is 4–5,considering Zr *** availability decreases with pH due to hydrogen fluoride and zirconium fluoride aqueous *** removal is initially rapid,with 50 wt.%removal in 7 min,followed by slow removal up to 68 wt.%after 72 h and follows second order rate *** removal was dominated by an ion exchange mechanism and resulting Zr–f bonds were observed using fourier-transform infrared *** presence of nickel sulfate decreased loading capacity compared to a salt-free *** maintained adsorption capacity through five cycles of loading and regeneration.

关键词： Hydrous zirconium oxide Nickel sulfate fluoride Adsorption Anion exchange

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