WorldWideScience

Sample records for human carrying capacity

  1. Carrying Capacity

    DEFF Research Database (Denmark)

    Schroll, Henning; Andersen, Jan; Kjærgård, Bente

    2012-01-01

    A spatial planning act was introduced inIndonesia 1992 and renewed in 2008. It emphasised the planning role of decentralised authorities. The spatial planning act covers both spatial and environmental issues. It defines the concept of carrying capacity and includes definitions of supportive...... carrying capacity (SCC) and assimilative carrying capacity (ACC). The act mandates that the latter two aspects must be taken into consideration in the local spatial plans. The present study aimed at developing a background for a national guideline for carrying capacity in Indonesian provinces and districts...... standard or governmental political objective exists. In most cases it was possible to select a set of indicators, including thresholds that are workable in a carrying capacity planning at the local administrative levels. Not all relevant sectors at the decentralized level were included. Indicators of SCC...

  2. Carrying Capacity

    DEFF Research Database (Denmark)

    Schroll, Henning; Andersen, Jan; Kjærgård, Bente

    2012-01-01

    A spatial planning act was introduced inIndonesia 1992 and renewed in 2008. It emphasised the planning role of decentralised authorities. The spatial planning act covers both spatial and environmental issues. It defines the concept of carrying capacity and includes definitions of supportive...... and ACC may increase the political focus on resources and environmental issues and may help to move local authorities towards a more holistic spatial planning approach. A carrying capacity approach could be an inspiration for local spatial planning in developing countries. A spatial planning act...... was introduced inIndonesia 1992 and renewed in 2008. It emphasised the planning role of decentralised authorities. The spatial planning act covers both spatial and environmental issues. It defines the concept of carrying capacity and includes definitions of supportive carrying capacity (SCC) and assimilative...

  3. Cultural Carrying Capacity: A Biological Approach to Human Problems.

    Science.gov (United States)

    Hardin, Garrett

    1992-01-01

    In discussing the human and cultural implications of scientific discoveries and knowledge, the biological concept of carrying capacity is explored. Maintaining that human beings are truly animals answering to principles that govern all animals, the author addresses the need for human populations to work within the context of culture and carrying…

  4. Wildlife carrying capacities in relation to human settlement

    Directory of Open Access Journals (Sweden)

    S.K. Eltringham

    1990-09-01

    Full Text Available Human encroachment into wildlife areas, which has increased almost exponentially over the past few decades, has usually resulted in the elimination of the larger species, particularly the large mammals. This is not an inevitable consequence and this paper considers the extent to which man and wildlife can coexist. There is a linear inverse relationship between human and elephant densities and the reasons for this are discussed with particular reference to Uganda. Such a relationship does not necessarily hold for all species and the outcome of increasing human pressure on wildlife habitats varies with a variety of factors including the species concerned, the rainfall, vegetation, soil and, above all, the attitudes of the people towards wildlife. Wild animals are more likely to be tolerated if they do no harm to human activities or if the harm they do is outweighed by the benefits to be obtained from their exploitation. In many parts of Africa utilisation is likely to be the best hope for the conservation of wildlife. Some examples are given of situations in which worthwhile carrying capacities of wildlife can be maintained in the presence of human activities.

  5. Wildlife carrying capacities in relation to human settlement

    OpenAIRE

    S.K. Eltringham

    1990-01-01

    Human encroachment into wildlife areas, which has increased almost exponentially over the past few decades, has usually resulted in the elimination of the larger species, particularly the large mammals. This is not an inevitable consequence and this paper considers the extent to which man and wildlife can coexist. There is a linear inverse relationship between human and elephant densities and the reasons for this are discussed with particular reference to Uganda. Such a relationship does not ...

  6. Evaluating Beijing's human carrying capacity from the perspective of water resource constraints.

    Science.gov (United States)

    Zhang, Yingxuan; Chen, Min; Zhou, Wenhua; Zhuang, Changwei; Ouyang, Zhiyun

    2010-01-01

    As the demands on limited water resources intensify, concerns are being raised about the human carrying capacity of these resources. However, few researchers have studied the carrying capacity of regional water resources. Beijing, the second-largest city in China, faces a critical water shortage that will limit the city's future development. We developed a method to quantify the carrying capacity of Beijing's water resources by considering water-use structures based on the proportions of water used for agricultural, industrial, and domestic purposes. We defined a reference structure as 45:22:33 (% of total, respectively), an optimized structure as 40:20:40, and an ideal structure as 50:15:35. We also considered four domestic water quotas: 55, 75, 95, and 115 m3/(person x yr). The urban carrying capacity of 10-12 million was closest to Beijing's actual 2003 population for all three water-use structures with urban domestic water use of 75 m3/(person x yr). However, after accounting for our underlying assumptions, the adjusted carrying capacity is closer to 5-6 million. Thus, Beijing's population in 2003 was almost twice the adjusted carrying capacity. Based on this result, we discussed the ecological and environmental problems created by Beijing's excessive population and propose measures to mitigate these problems.

  7. Carrying Capacity:An Overview

    Institute of Scientific and Technical Information of China (English)

    Chen Shaofeng

    2004-01-01

    The concept of carrying capacity is derived from ecology, with widespread contentions of its theoretical connotations and applications in the international academic community, especially the impact of human activities on the environment.Disputes on carrying capacity have been occurring not only among biologists and ecologists, but also among mainstream economists. Based on their efforts,the author makes an attempt to describe its origin,connotations, problems, measurement, and at the same time note the latest international progress in this field.

  8. Ecological Footprints and Appropriated Carrying Capacity: Measuring the Natural Capital Requirements of the Human Economy.

    Science.gov (United States)

    Ress, William E.; Wackernagel, Mathis

    1996-01-01

    Contrasts conventional economic rationality with economic principles. Develops an empirical approach based on a reinterpretation of carrying capacity that can account for technological advances and trade. Discusses the necessity of diverting much of the present consumption to investment in the maintenance of natural capital stocks. (AIM)

  9. 25 CFR 167.6 - Carrying capacities.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Carrying capacities. 167.6 Section 167.6 Indians BUREAU... Carrying capacities. (a) The Commissioner of Indian Affairs on June 26, 1943, promulgated the authorized carrying capacity for each land management district of the Navajo Reservation. (b) Recommended...

  10. 7 CFR 1437.402 - Carrying capacity.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Carrying capacity. 1437.402 Section 1437.402... Determining Coverage of Forage Intended for Animal Consumption § 1437.402 Carrying capacity. (a) CCC will establish a carrying capacity for all grazed forage present in the county for purposes of administering...

  11. ENVIRONMENTAL CARRYING CAPACITY BASED ON SPATIAL PLANNING

    OpenAIRE

    Luthfi Muta'ali

    2013-01-01

    The aims of this research were to examine environmental carrying capacity analyzed based on aspects of spatial planning and eco-region. The result showed that Kulonprogo Regency has low value of environmental carrying capacity and can only support as much as 79.81% of its total population. Analysis of variance showed significant difference of environmental carrying capacity of protected and cultivated area. The main factor among 12 variables determining the degree of environmen...

  12. Bivalve carrying capacity in coastal ecosystems

    NARCIS (Netherlands)

    Dame, R.F.; Prins, T.C.

    1998-01-01

    carrying capacity of suspension feeding bivalves in 11 coastal and estuarine ecosystems is examined. Bivalve carrying capacity is defined in terms of water mass residence time, primary production time and bivalve clearance time. Turnover times for the 11 ecosystems are compared both two and three di

  13. The Concept of Carrying Capacity in Tourism

    Directory of Open Access Journals (Sweden)

    Josef Zelenka

    2014-05-01

    Full Text Available Carrying capacity is often pragmatically, theoretically as well as purely intuitively considered as a concept in the context of tourism sustainability. The carrying capacity application has the greatest potential in protected areas, in frequently visited cultural and natural attractions, and in relation to sustaining of the lifestyle of the local community and tourism destination potential in general. Despite its importance, partial applications, determination of basic theoretical principles, and specifying connection to the other theoretical concepts in tourism (particularly destination life cycle, LAC concept, visitors management, there still is a rightful opinion of some authors suggesting that there is no consistent theory of tourism carrying capacity. This theory would be the base for sophisticated practical carrying capacity applications. This paper is therefore focused on introduction of the theoretical concept of carrying capacity, which can be discussed and possibly further elaborated.

  14. Measuring Social Carrying Capacity: An Exploratory Study

    OpenAIRE

    López-Bonilla, Jesús Manuel; López-Bonilla, Luis Miguel

    2007-01-01

    The tourist carrying capacity commands a growing interest given that it is closely linked with sustainable tourist development. The justification of the utility of this concept is given by means of a simple and efficient methodological proposal, by analysing the social carrying capacity. To this end, an empirical application is carried out in the Western Andalusia. In some of the cases analysed, the satisfaction of the tourist is found to decline when the levels of the tourist use are higher ...

  15. Global change and carrying capacity: Implications for life on Earth

    Science.gov (United States)

    Ehrlich, Paul R.; Daily, Gretchen C.; Ehrlich, Anne H.; Matson, Pamela; Vitousek, Peter

    1989-01-01

    Determining the long-term number of people that the planet can support without irreversibly reducing its ability to support people in the future, i.e., the carrying capacity of the Earth, is an exceedingly complex problem. About all that is known for certain is that, with present and foreseeable technologies, the human population has already exceeded the capacity. The reduction in carrying capacity that can be expected to result from direct human impacts on resources and the environment and from our indirect impacts of the climate system is discussed. Global warming and modeling global change and food security are also discussed with respect to carrying capacity.

  16. Global change and carrying capacity: Implications for life on Earth

    Science.gov (United States)

    Ehrlich, Paul R.; Daily, Gretchen C.; Ehrlich, Anne H.; Matson, Pamela; Vitousek, Peter

    1989-01-01

    Determining the long-term number of people that the planet can support without irreversibly reducing its ability to support people in the future, i.e., the carrying capacity of the Earth, is an exceedingly complex problem. About all that is known for certain is that, with present and foreseeable technologies, the human population has already exceeded the capacity. The reduction in carrying capacity that can be expected to result from direct human impacts on resources and the environment and from our indirect impacts of the climate system is discussed. Global warming and modeling global change and food security are also discussed with respect to carrying capacity.

  17. Optimal growth trajectories with finite carrying capacity.

    Science.gov (United States)

    Caravelli, F; Sindoni, L; Caccioli, F; Ududec, C

    2016-08-01

    We consider the problem of finding optimal strategies that maximize the average growth rate of multiplicative stochastic processes. For a geometric Brownian motion, the problem is solved through the so-called Kelly criterion, according to which the optimal growth rate is achieved by investing a constant given fraction of resources at any step of the dynamics. We generalize these finding to the case of dynamical equations with finite carrying capacity, which can find applications in biology, mathematical ecology, and finance. We formulate the problem in terms of a stochastic process with multiplicative noise and a nonlinear drift term that is determined by the specific functional form of carrying capacity. We solve the stochastic equation for two classes of carrying capacity functions (power laws and logarithmic), and in both cases we compute the optimal trajectories of the control parameter. We further test the validity of our analytical results using numerical simulations.

  18. Optimal growth trajectories with finite carrying capacity

    Science.gov (United States)

    Caravelli, F.; Sindoni, L.; Caccioli, F.; Ududec, C.

    2016-08-01

    We consider the problem of finding optimal strategies that maximize the average growth rate of multiplicative stochastic processes. For a geometric Brownian motion, the problem is solved through the so-called Kelly criterion, according to which the optimal growth rate is achieved by investing a constant given fraction of resources at any step of the dynamics. We generalize these finding to the case of dynamical equations with finite carrying capacity, which can find applications in biology, mathematical ecology, and finance. We formulate the problem in terms of a stochastic process with multiplicative noise and a nonlinear drift term that is determined by the specific functional form of carrying capacity. We solve the stochastic equation for two classes of carrying capacity functions (power laws and logarithmic), and in both cases we compute the optimal trajectories of the control parameter. We further test the validity of our analytical results using numerical simulations.

  19. Error propagation in energetic carrying capacity models

    Science.gov (United States)

    Pearse, Aaron T.; Stafford, Joshua D.

    2014-01-01

    Conservation objectives derived from carrying capacity models have been used to inform management of landscapes for wildlife populations. Energetic carrying capacity models are particularly useful in conservation planning for wildlife; these models use estimates of food abundance and energetic requirements of wildlife to target conservation actions. We provide a general method for incorporating a foraging threshold (i.e., density of food at which foraging becomes unprofitable) when estimating food availability with energetic carrying capacity models. We use a hypothetical example to describe how past methods for adjustment of foraging thresholds biased results of energetic carrying capacity models in certain instances. Adjusting foraging thresholds at the patch level of the species of interest provides results consistent with ecological foraging theory. Presentation of two case studies suggest variation in bias which, in certain instances, created large errors in conservation objectives and may have led to inefficient allocation of limited resources. Our results also illustrate how small errors or biases in application of input parameters, when extrapolated to large spatial extents, propagate errors in conservation planning and can have negative implications for target populations.

  20. Increased carrying capacity with perennial forage kochia

    Science.gov (United States)

    Carrying capacity can be increased on grass-dominated rangeland pastures by including perennial forage kochia (Kochia prostrata) as one of the plant components. The objectives of the study reported here were to compare the differences of traditional winter pastures versus pastures with forage kochi...

  1. Rapid Population Growth and Human Carrying Capacity: Two Perspectives. World Bank Staff Working Papers No. 690 and Population and Development Series No. 15.

    Science.gov (United States)

    Mahar, Dennis J., Ed.; And Others

    Two perspectives on carrying capacity and population growth are examined. The first perspective, "Carrying Capacity and Rapid Population Growth: Definition, Cases, and Consequences" (Robert Muscat), explores the possible meanings of the idea of carrying capacity under developing country conditions, looks at historical and present-day cases of…

  2. Carrying capacity: the tradition and policy implications of limits

    Directory of Open Access Journals (Sweden)

    Virginia Deane Abernethy

    2001-01-01

    Full Text Available ABSTRACT: Within just the last few centuries, science and technology have enlarged human capabilities and population size until humans now take, for their own use, nearly half of the Earth's net terrestrial primary production. An ethical perspective suggests that potentials to alter, or further increase, humanity's use of global resources should be scrutinized through the lenses of self-interested foresightedness and respect for non-human life. Without overtly invoking ethics, studies of the carrying capacity achieve just this objective. Carrying capacity is an ecological concept that expresses the relationship between a population and the natural environment on which it depends for ongoing sustenance. Carrying capacity assumes limits on the number of individuals that can be supported at a given level of consumption without degrading the environment and, therefore, reducing future carrying capacity. That is, carrying capacity addresses long-term sustainability. Worldviews differ in the importance accorded to the carrying capacity concept. This paper addresses three worldviews - ecological, romantic, and entrepreneurial - and explores the ethics and the policy implications of their contrasting perspectives.

  3. Estimating the recreational carrying capacity of a lowland river section.

    Science.gov (United States)

    Lorenz, Stefan; Pusch, Martin T

    2012-01-01

    Recreational boating represents a major human use of inland waters in many regions. However, boating tourism may affect the ecological integrity of surface waters in multiple ways. In particular, surface waves produced by boating may disturb freshwater invertebrates, such as interrupting the filtration activity of benthic mussels. As mussels may significantly contribute to self-purification, disturbance may have crucial impacts on water quality, and thus on water tourism. In this paper we calculate the carrying capacity of a river section for sustainable boating tourism based on the preservation of water quality. This approach is complemented by spatial and social approaches for carrying capacity estimates. The ecological carrying capacity significantly decreases with lower water levels during summer. Hence, the analysis of variables that influence the river's carrying capacity allows the formation of recommendations for management measures that integrate social, touristic and ecological aspects.

  4. Evaluation of carrying capacity and territorial environmental sustainability

    Directory of Open Access Journals (Sweden)

    Giuseppe Ruggiero

    2012-09-01

    Full Text Available Land use has a great impact on environmental quality, use of resources, state of ecosystems and socio-economic development. Land use can be considered sustainable if the environmental pressures of human activities do not exceed the ecological carrying capacity. A scientific knowledge of the capability of ecosystems to provide resources and absorb waste is a useful and innovative means of supporting territorial planning. This study examines the area of the Province of Bari to estimate the ecosystems’ carrying capacity, and compare it with the current environmental pressures exerted by human activities. The adapted methodology identified the environmentally sustainable level for one province.

  5. Integrated Coastal Zone Planning Based on Environment Carrying Capacity Analysis

    Science.gov (United States)

    Miharja, M.; Arsallia, S.

    2017-07-01

    Coastal zone is a crucial area in terms of planning development. It holds high economic value, which affect to increasing number of inhabitants living in the area. As a result, this condition influences environmental degradation. Thus, in every attempt towards coastal zone development, it is crucial to always refer to environment carrying capacity. Carrying capacity is the limit of a certain coastal zone capability to support all human created activities, in which all ecological performances are maintained at sustainable level. The failure to establish strong and clear method and regulation on carrying capacity analysis will lead to a very risky coastal zone development, which in turn would threat the area’s sustainability. This paper discusses method for analysing carrying capacity of coastal zone as important input for the area development plan. Two key parameters, i.e. land and clean water carrying capacities are discussed to form carrying capacity analytical method. Furthermore, an empirical data of Ambon Bay, Moluccas Province, is used to illustrate the operationalization of the method.

  6. Carrying Capacity of Marine Region in Liaoning Province

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Carrying capacity is one of important studies on coordinating development of population, resources, and environment. At present, the researches on it mainly concentrate on the carrying capacity for population and economy,such as the water resources carrying capacity, the land resources carrying capacity, the environment carrying capacity,etc. Based on the related theories and methods, this paper creatively proposed the concept and meaning of carrying capacity of marine region, and formed the appraisal system. According to the developing situation of marine economy of Liaoning Province in recent years, and by employing the method of the state space, this paper also measured the cartying capacity and carrying state of marine region and discussed the sustainable problems of marine economy of Liaoning. The research results show that the carrying state of marine region of Liaoning is in the state of overloading at present, but taking a favorable turn.

  7. Information carrying capacity of a cosmological constant

    Science.gov (United States)

    Simidzija, Petar; Martín-Martínez, Eduardo

    2017-01-01

    We analyze the exchange of information in different cosmological backgrounds when sender and receiver are timelike separated and communicate through massless fields (without the exchange of light signals). Remarkably, we show that the dominance of a cosmological constant makes the amount of recoverable information imprinted in the field by the sender extremely resilient: it does not decay in time or with the spatial separation of the sender and receiver, and it actually increases with the rate of expansion of the Universe. This is in stark contrast with the information carried by conventional light signals and with previous results on timelike communication through massless fields in matter-dominated cosmologies.

  8. Regional carrying capacity: case studies of Bohai Rim area

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Carrying capacity research has been carried out for a long time. However, synthesized carrying capacity researches based on systematic views began only in the 1970s. There is even less work done in China. This paper tries to address both synthesized carrying capacity research and its utilization in China. State spaces method from the systematic science was borrowed to construct the conceptual model of regional carrying capacity. Based on the conceptual model and the surveys in the Bohai Rim area, we construct a representative indicators system for quantifying regional carrying capacity in the Bohai Rim. While employing system dynamic models we simulated the evolving trend of both the regional carrying states and regional carrying capacity from 1999 to 2015. The results proved the statement that Bohai Rim is overall over-capacity for a long time and will be over-capacity in the foreseeable future. Among all the restriction factors, water shortage and environmental pollution stand out to be the two primary obstacles for Bohai Rim's sustainable development.Regional differentiation analysis further indicates that coastal areas of the Bohai Rim burden more than its overall level. However, Shandong province shows some good signs in addressing the regional carrying capacity issues. The research is successful in addressing the quantification of regional carrying capacity issues, but nonetheless it needs further refinery and more information.

  9. Research on Psychological Carrying Capacity of Tourism Destination

    Institute of Scientific and Technical Information of China (English)

    Fan Zhiyong; Zhong Sheng

    2009-01-01

    As a part of the carrying capacity system of tourism destination,tourism psychological carrying capacity and its makeup are very important indexes which reflect the harmonious development of tourism destination develops harmoniously,but the academy has not paid enough attention to them.Based on the concept and connotation of psychological carrying capacity,this paper explains the influencing factors which affect the psychological capacity of the tourist and the resident after the acknowledged concept,and then designs a harmonious development model of tourism destination.Finally,it offers some countermeasures against the overloading psychological capacity.

  10. Study on Tourist Carrying Capacity Based on Matter Element Analysis

    Institute of Scientific and Technical Information of China (English)

    LiuYunguo; FanTing; LiXin; ZhouMing; WangXianhai

    2005-01-01

    This paper proposes that it is necessary to implement the concept of tourist carrying capacity to facilitate the tourism planning, and presents a method to evaluate the carrying capacity. The method called matter element analysis can solve the uncertain and incompatible problem of the evaluated factors in assessing carrying capacity.The current state of a destination's carrying capacity can be determined by establishing the standard indexes and the matter element model. Through the evaluating of the travel industry zones of the Autonomous Prefecture of Western Hunan, the method is proved to be simple and feasible, and it is improved to be significant for the tourism planning and determination as well as the sustainable development of the regional tourism.

  11. Determination of the sediment carrying capacity based on perturbed theory.

    Science.gov (United States)

    Ni, Zhi-hui; Zeng, Qiang; Li-chun, Wu

    2014-01-01

    According to the previous studies of sediment carrying capacity, a new method of sediment carrying capacity on perturbed theory was proposed. By taking into account the average water depth, average flow velocity, settling velocity, and other influencing factors and introducing the median grain size as one main influencing factor in deriving the new formula, we established a new sediment carrying capacity formula. The coefficients were determined by the principle of dimensional analysis, multiple linear regression method, and the least square method. After that, the new formula was verified through measuring data of natural rivers and flume tests and comparing the verified results calculated by Cao Formula, Zhang Formula, Li Formula, Engelung-Hansen Formula, Ackers-White Formula, and Yang Formula. According to the compared results, it can be seen that the new method is of high accuracy. It could be a useful reference for the determination of sediment carrying capacity.

  12. The logistic model-generated carrying capacities for wild herbivores ...

    African Journals Online (AJOL)

    Jesse

    Modelled as discrete-time logistic equations with fixed carrying capacities, it captures the wildlife herbivore population dynamics. Time series data, covering a period ..... Building Models for Conservation and. Wildlife Management. (New York ...

  13. Langkawi Island, Social Aspect and the Carrying Capacity

    OpenAIRE

    Mohamad Diana; Jaafar Mastura; Marzuki Azizan

    2014-01-01

    The aptitude to convince a range of preferences has facilitated the island tourism attractions to achieve international recognition and at present KILIM Geopark is enjoyed by a prominent percentage of individuals wide-reaching. Conventional knowledge has that the island attractions are operating on the limited immobile resources, of which, have raised the scholars’ concerns over the carrying capacity issue. When analyzing carrying capacity, scholars have traditionally focused on the environme...

  14. Boundary slippage for generating hydrodynamic load-carrying capacity

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yong-bin

    2008-01-01

    Boundary slippage is used to generate the load-carrying capacity of the hydrodynamic contact between two parallel plane surfaces.In the fluid inlet zone,the fluidcontact interfacial shear strength on a stationary surface is set at low to generate boundary slippage there,while in the fluid outlet zone the fluid-contact interfacial shear strength on the stationary surface is set at high enough to prevent the occurrence of boundary slippage.The fluid-contact interfacial shear strength on the entire moving surface is set at high enough to prevent boundary slippage on the moving surface.These hydrodynamic contact configurations are analyzed to generate the pronounced load-carrying capacity.The optimum ratio of the outlet zone width to the inlet zone width for the maximum load-carrying capacity of the whole contact is found to be 0.5.

  15. Hierarchical population model with a carrying capacity distribution

    CERN Document Server

    Indekeu, J O

    2002-01-01

    A time- and space-discrete model for the growth of a rapidly saturating local biological population $N(x,t)$ is derived from a hierarchical random deposition process previously studied in statistical physics. Two biologically relevant parameters, the probabilities of birth, $B$, and of death, $D$, determine the carrying capacity $K$. Due to the randomness the population depends strongly on position, $x$, and there is a distribution of carrying capacities, $\\Pi (K)$. This distribution has self-similar character owing to the imposed hierarchy. The most probable carrying capacity and its probability are studied as a function of $B$ and $D$. The effective growth rate decreases with time, roughly as in a Verhulst process. The model is possibly applicable, for example, to bacteria forming a "towering pillar" biofilm. The bacteria divide on randomly distributed nutrient-rich regions and are exposed to random local bactericidal agent (antibiotic spray). A gradual overall temperature change away from optimal growth co...

  16. Effects of box handle position and carrying range on bi-manual carrying capacity for females.

    Science.gov (United States)

    Wu, Swei-Pi; Loiu, Yi; Chien, Te Hong

    2015-01-01

    This study utilizes a psychophysical approach to examine the effects on carrying capacity for bi-manual carrying tasks involving different handle positions and carrying ranges. A total of 16 female subjects participated in the experiment in groups of two people, and each group of subjects performed the tasks in a random order with 12 different combinations of carrying task. The independent variables are handle position (upper, middle, lower) and carrying range (F-F: floor height carried to floor height, F-W: floor height carried to waist height, W-W: waist height carried to waist height, W-F: waist height carried to floor height), the dependent variable is the maximum acceptable carried weight (MAWC), heart rate (HR), and the rating of perceived exertion (RPE). The results show that the handle position has a significant effect on MAWC and overall RPE but no significant effect on HR. Carrying range has a significant effect on the MAWC and HR, but no significant effect on overall HR. The handle position and carrying range have a significant interaction on the MAWC and HR. The RPE for different body parts shows significant differences, and the hands feel the most tired. Overall, this study confirms that the lower handle position with the W-W carrying range is the best combination for a two-person carrying task.

  17. Model Modification and Application on Carrying Capacity of Relative Resources

    Institute of Scientific and Technical Information of China (English)

    Li Zehong; Dong Suocheng; Gao Dan

    2009-01-01

    Based on the retrospection of researches on carry-ing capacity, this article reviewed systematically the research progresses on carrying capacity of relative resources (CCRR).Then the viewpoint was put forward that CCRR is not an ap-propriate method of appraising the regional sustainability, but a sound way to obtain cognition for coordinating spatial loca-tion and flow of population and economy.However, as the most popular computing method of CCRR, the Weighting Linear Sum Model is defective in the random of weight choice and the neglect of matching among different resources.Therefore, this article established the Geometric Model on CCRR based on modifying Weighting Linear Sum Model, which can be used to appraise regions where resources are close matching.Em-ploying the Geometric Model, the article empirically analyzed the population and economic CCRR in Hubei Province from 1978 to 2006.The result indicates that the population in Hubei Province is overloading while the economic carrying capacity is abundant compared to the whole country, and the economic insufficiency restricts the population carrying capacity.In the future, Hubei Province will become one of the core developing zones which are characterized by economic conglomeration.

  18. Modeling the Flexural Carrying Capacity of Corroded RC Beam

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-hui; LIU Xi-la

    2008-01-01

    Considering the change of bond strength between corroded steel and concrete, flexural carrying ca-pacity of corroded reinforced concrete (RC) beam was calculated. On the basis of the condition of equilibriumof forces and compatibility of deformations for the whole beam, a model for the prediction of flexural carryingcapacity of the corroded RC beam was proposed. Comparison of the model's predictions with the experimentalresults published in the literature shows the practicality of the proposed method.

  19. Human and Financial Capital in the Rural Educational Environment: The Effects of Exceeding the Carrying Capacity Threshold on Standardized Test Scores in Rural Indiana.

    Science.gov (United States)

    Peoples, Glenn

    The Rural Educational Environment (REE) is a complex mixture of demographic and economic forces that interact to impact the rural school corporation. The condition of REE financial and human capital indicates REE health and may influence student performance on standardized tests. This paper proposes an ecosystem model of the impact of financial,…

  20. Langkawi Island, Social Aspect and the Carrying Capacity

    Directory of Open Access Journals (Sweden)

    Mohamad Diana

    2014-01-01

    Full Text Available The aptitude to convince a range of preferences has facilitated the island tourism attractions to achieve international recognition and at present KILIM Geopark is enjoyed by a prominent percentage of individuals wide-reaching. Conventional knowledge has that the island attractions are operating on the limited immobile resources, of which, have raised the scholars’ concerns over the carrying capacity issue. When analyzing carrying capacity, scholars have traditionally focused on the environmental part, hence, this working paper is motivated to convey onto the table issues relating to the social characteristics. This particular paper employed the self-administered questionnaire survey instrument which was structured to answer the two-fold objective specifically the tourists’ satisfaction level with their tourism experience and knowledge gap in relation to improving the island tourism. Targeting the tourists with minimum age of 18, this working paper collects information on the tourists’ perception towards hospitality, facilities and safety issues. In addition, this working paper comes to scrutinize different results of demographic factors as compared to what have been documented by earlier studies. Besides, it is learned that ‘safety issue’ variable plays an important role when it comes to the following factors: tourist arrival, access to facilities and tourism experience.

  1. HLA-associated alterations in replication capacity of chimeric NL4-3 viruses carrying gag-protease from elite controllers of human immunodeficiency virus type 1.

    Science.gov (United States)

    Miura, Toshiyuki; Brockman, Mark A; Brumme, Zabrina L; Brumme, Chanson J; Pereyra, Florencia; Trocha, Alicja; Block, Brian L; Schneidewind, Arne; Allen, Todd M; Heckerman, David; Walker, Bruce D

    2009-01-01

    Human immunodeficiency virus type 1 (HIV-1)-infected persons who maintain plasma viral loads of viruses (VRC) obtained from EC (n = 54) compared to those from chronic progressors (CP; n = 41) by constructing chimeric viruses using patient-derived gag-protease sequences amplified from plasma HIV RNA and inserted into an NL4-3 backbone. The chimeric viruses generated from EC displayed lower VRC than did viruses from CP (P viruses from B*57(+) EC (n = 18) demonstrated lower VRC than did viruses from B*57(+) CP (n = 8, P = 0.0245). Differences in VRC between EC and CP were also observed for viruses obtained from individuals expressing no described "protective" alleles (P = 0.0065). Intriguingly, two common HLA alleles, A*02 and B*07, were associated with higher VRC (P = 0.0140 and 0.0097, respectively), and there was no difference in VRC between EC and CP sharing these common HLA alleles. These findings indicate that cytotoxic T-lymphocyte (CTL) selection pressure on gag-protease alters VRC, and HIV-specific CTLs inducing escape mutations with fitness costs in this region may be important for strict viremia control in EC of HIV.

  2. Enhancing human capacities

    CERN Document Server

    Savulescu, Julian; Kahane, Guy

    2011-01-01

    Enhancing Human Capacities is the first to review the very latest scientific developments in human enhancement. It is unique in its examination of the ethical and policy implications of these technologies from a broad range of perspectives. Presents a rich range of perspectives on enhancement from world leading ethicists and scientists from Europe and North America The most comprehensive volume yet on the science and ethics of human enhancement Unique in providing a detailed overview of current and expected scientific advances in this area Discusses both general conceptual and ethical issues

  3. Modeling symbiosis by interactions through species carrying capacities

    Science.gov (United States)

    Yukalov, V. I.; Yukalova, E. P.; Sornette, D.

    2012-08-01

    We introduce a mathematical model of symbiosis between different species by taking into account the influence of each species on the carrying capacities of the others. The modeled entities can pertain to biological and ecological societies or to social, economic and financial societies. Our model includes three basic types: symbiosis with direct mutual interactions, symbiosis with asymmetric interactions, and symbiosis without direct interactions. In all cases, we provide a complete classification of all admissible dynamical regimes. The proposed model of symbiosis turned out to be very rich, as it exhibits four qualitatively different regimes: convergence to stationary states, unbounded exponential growth, finite-time singularity, and finite-time death or extinction of species.

  4. The Population Carrying Capacity of Water Resources in Yulin City

    Institute of Scientific and Technical Information of China (English)

    Lijuan; DANG; Yong; XU; Zhiqiang; WANG

    2014-01-01

    Assessing the water resource carrying capacity is beneficial for measuring the scale of industry and population agglomeration,and also avoiding the contradiction between increasing people and decreasing available water resource,due to the expansion of industry and city size.Based on the prediction model of optimum population development size,by using hydrological data,also with the demographic data from 1956 to 2010,this article analyzes and predicts the urban moderate scale under the limit of the water resource in the future of Yulin City by GIS. The main conclusions are as follows. There is growing tendency of water resources overloading. According to the result of model simulation,by2015,the overload rate of population size will be 1. 04. By 2020,the overload rate of population size will grow up to 1. 08. The oversized population mainly comes from cities and towns. The overload rate for cities and towns in 2015 and 2020 is 1. 89 and 1. 73,respectively. With the expansion of cities and industries,suburban areas could have a great potential for carrying population,because lots of suburban people may move to cities and towns according to prediction. In view of the above-mentioned facts,the population size should be controlled in a reasonable range.

  5. Spatial patterns of ecological carrying capacity supply-demand balance in China at county level

    Institute of Scientific and Technical Information of China (English)

    LIU Dong; FENG Zhiming; YANG Yanzhao; YOU Zhen

    2011-01-01

    A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependencies between human and nature.China's ecological balance between supply and demand has become a global concern and is widely debated.In this study the 'Ecological Footprint' method was used to analyze the supply-demand balance of China's ecological carrying capacity.Firstly,the ecological supply and demand balance was calculated and evaluated,and secondly,the ecological carrying capacity index (ECCI) was derived for each county of China in 2007,and finally this paper systematically evaluated the ecological carrying capacity supply-demand balance of China.The results showed that ecological deficit appeared to be the main characteristic of ecological carrying capacity supply-demand balance in 2007 of China at county scale.In general,more than four-fifths of the Chinese population was concentrated in less than one-third of the land area and more than two-thirds of the land.area was inhabited by less than one-fifth of the population.The spatial distribution of the ecological carrying capacity demand-supply was unbalanced ranging from significant overloading to affluence from southeastern to northwestern part of China.It appeared to be more dominant in regions located at coastal areas which are attracted by migrants and had a generally higher population density.Along with the rapid development and urbanization trends in China,ecological deficits in these regions will become more severe.

  6. Carrying capacity in agriculture: environmental significance and some related patents.

    Science.gov (United States)

    da Silva, Alexandre M

    2009-06-01

    Agriculture is one of the most important and possibly the oldest economic activity developed by humans. This activity was developed extensively and is becoming more and more dependent on development of technologies. The goal of this manuscript was examining some patents related to technologies developed for improving crop yields. Such patents are mainly related to more efficient formulations of agrochemicals and management techniques of plants, cattle and natural resources. A brief comment is carried out about bioprospection and related problems, relating, for example the case of Cupuaçu. The article is concluded mentioning that the development of policies and management strategies that increase agricultural yield and simultaneously preserve or conserve natural resources should also be prioritized, because certainly this is the only way we have to get the real sustainability and to improve life quality abroad the world.

  7. Examining the Resilience of Crop Production, Livestock Carrying Capacity, and Woodland Density in a Rural Zimbabwean Socio-Ecological System Using Agent-Based Models Representing Human Management Decisions

    Science.gov (United States)

    Eitzel Solera, M. V.; Neves, K.; Veski, A.; Solera, J.; Omoju, O. E.; Mawere Ndlovu, A.; Wilson, K.

    2016-12-01

    As climate change increases the pressures on arid ecosystems by changing timing and amount of rainfall, understanding the ways in which human management choices affect the resilience of these systems becomes key to their sustainability. On marginal farmland in Mazvihwa, Midlands Province, the historical carrying capacity of livestock has been consistently surprisingly high. We explore this phenomenon by building an agent-based model in NetLogo from a wealth of long-term data generated by the community-based participatory research team of The Muonde Trust, a Zimbabwean non-governmental organization. We combine the accumulated results of 35 years of indigenous and local knowledge with national datasets such as rainfall records. What factors keep the carrying capacity high? What management choices can maintain crops, livestock, and woodland at levels necessary for the community's survival? How do these choices affect long-term sustainability, and does increasing resilience at one scale reduce resilience at another scale? We use our agent-based model to explore the feedbacks between crops, livestock, and woodland and the impacts of various human choices as well as temporal and spatial ecological variation. By testing different scenarios, we disentangle the complex interactions between these components. We find that some factors out of the community's control can strongly affect the sustainability of the system through times of drought, and that supplementary feed may maintain livestock potentially at the expense of other resources. The challenges to resilience encountered by the farmers in Mazvihwa are not unique - many indigenous and rural people face drought and the legacies of colonialism, which contribute to lowered resilience to external challenges such as climate change, epidemics, and political instability. Using the agent-based model as a tool for synthesis and exploration initiates discussion about resilience-enhancing management choices for Mazvihwa's farmer-researchers.

  8. Dynamic Carrying Capacity Analysis of Double-Row Four-Point Contact Ball Slewing Bearing

    OpenAIRE

    Yunfeng Li; Di Jiang

    2015-01-01

    Carrying capacity is the most important performance index for slewing bearings. Maximizing the carrying capacity of slewing bearing is one pursuing goal for the bearing designer; this is usually realized by optimizing the design parameters. A method of analyzing the carrying capacity of double-row four-point contact ball slewing bearing by using dynamic carrying capacity surfaces was proposed in this paper. Based on the dynamic load carrying capacity surface of the slewing bearing, the effect...

  9. Carrying capacity of U.S. agricultural land: Ten diet scenarios

    Directory of Open Access Journals (Sweden)

    Christian J. Peters

    2016-07-01

    Full Text Available Abstract Strategies for environmental sustainability and global food security must account for dietary change. Using a biophysical simulation model we calculated human carrying capacity under ten diet scenarios. The scenarios included two reference diets based on actual consumption and eight “Healthy Diet” scenarios that complied with nutritional recommendations but varied in the level of meat content. We considered the U.S. agricultural land base and accounted for losses, processing conversions, livestock feed needs, suitability of land for crops or grazing, and land productivity. Annual per capita land requirements ranged from 0.13 to 1.08 ha person-1 year-1 across the ten diet scenarios. Carrying capacity varied from 402 to 807 million persons; 1.3 to 2.6 times the 2010 U.S. population. Carrying capacity was generally higher for scenarios with less meat and highest for the lacto-vegetarian diet. However, the carrying capacity of the vegan diet was lower than two of the healthy omnivore diet scenarios. Sensitivity analysis showed that carrying capacity estimates were highly influenced by starting assumptions about the proportion of cropland available for cultivated cropping. Population level dietary change can contribute substantially to meeting future food needs, though ongoing agricultural research and sustainable management practices are still needed to assure sufficient production levels.

  10. Delivering Transgenic DNA Exceeding the Carrying Capacity of AAV Vectors.

    Science.gov (United States)

    Hirsch, Matthew L; Wolf, Sonya J; Samulski, R J

    2016-01-01

    Gene delivery using recombinant adeno-associated virus (rAAV) has emerged to the forefront demonstrating safe and effective phenotypic correction of diverse diseases including hemophilia B and Leber's congenital amaurosis. In addition to rAAV's high efficiency of transduction and the capacity for long-term transgene expression, the safety profile of rAAV remains unsoiled in humans with no deleterious vector-related consequences observed thus far. Despite these favorable attributes, rAAV vectors have a major disadvantage preventing widespread therapeutic applications; as the AAV capsid is the smallest described to date, it cannot package "large" genomes. Currently, the packaging capacity of rAAV has yet to be definitively defined but is approximately 5 kb, which has served as a limitation for large gene transfer. There are two main approaches that have been developed to overcome this limitation, split AAV vectors, and fragment AAV (fAAV) genome reassembly (Hirsch et al., Mol Ther 18(1):6-8, 2010). Split rAAV vector applications were developed based upon the finding that rAAV genomes naturally concatemerize in the cell post-transduction and are substrates for enhanced homologous recombination (HR) (Hirsch et al., Mol Ther 18(1):6-8, 2010; Duan et al., J Virol 73(1):161-169, 1999; Duan et al., J Virol 72(11):8568-8577, 1998; Duan et al., Mol Ther 4(4):383-391, 2001; Halbert et al., Nat Biotechnol 20(7):697-701, 2002). This method involves "splitting" the large transgene into two separate vectors and upon co-transduction, intracellular large gene reconstruction via vector genome concatemerization occurs via HR or nonhomologous end joining (NHEJ). Within the split rAAV approaches there currently exist three strategies: overlapping, trans-splicing, and hybrid trans-splicing (Duan et al., Mol Ther 4(4):383-391, 2001; Halbert et al., Nat Biotechnol 20(7):697-701, 2002; Ghosh et al., Mol Ther 16(1):124-130, 2008; Ghosh et al., Mol Ther 15(4):750-755, 2007). The other major

  11. Effects of carrying methods and box handles on two-person team carrying capacity for females.

    Science.gov (United States)

    Wu, Swei-Pi; Chang, Shu-Yu

    2010-07-01

    This study used a psychophysical approach to examine the effects of carrying methods and the presence or absence of box handles on the maximum acceptable weight carried and resulting responses (heart rate and rating of perceived exertion) in a two-person carrying task. After training, 16 female subjects performed a two-person carrying task at knuckle height for an 8-h work period. Each subject performed 4 different carrying combinations two times. The independent variables were carrying methods (parallel and tandem walking) and box handles (with and without handles). For comparison with two-person carrying, the subjects also performed one-person carrying. The results showed that the maximum acceptable weight carried (MAWC), heart rate (HR), and rating of perceived exertion (RPE) were significantly affected by the presence of box handles. However, the subjects' MAWC, HR, and RPE values were not significantly influenced by the carrying methods. The test-retest reliability of the psychophysical approach was 0.945. The carrying efficiency of two-person carrying was 96.2% of the one-person carrying method. In general, the use of box with handles allows the subjects to carry a higher MAWC (with lower HR and RPE) compared to carrying boxes without handles.

  12. [Ecotourism carrying capacity of Hangzhou Xixi National Wetland Park in China].

    Science.gov (United States)

    Li, Rui; Rong, Liang

    2007-10-01

    In this paper, an integrated estimation on the ecotourism carrying capacity of Hangzhou Xixi National Wetland Park in China was made from the aspects of ecological carrying capacity, spatial carrying capacity, facility carrying capacity, management carrying capacity, and psychological carrying capacity. The results indicated that the tourism carrying capacity of the Park was 4 145 - 6 450 persons per day. The rational distance between man and bird was first adopted to determine the ecotourism carrying capacity of wetland, which provided an effective solution both to fully ensure bird safety and to appropriately develop wetland tourism. The estimation of psychological carrying capacity based on tourist satisfaction degree reflected more objectively the extent the tourist demands satisfied at the planning, construction and management of tour places. Such an integrated estimation method based on the distance between man and bird and the tourist satisfaction degree could be of practical and instructive significances in the planning and management of wetland parks.

  13. Estimating landscape carrying capacity through maximum clique analysis.

    Science.gov (United States)

    Donovan, Therese M; Warrington, Gregory S; Schwenk, W Scott; Dinitz, Jeffrey H

    2012-12-01

    Habitat suitability (HS) maps are widely used tools in wildlife science and establish a link between wildlife populations and landscape pattern. Although HS maps spatially depict the distribution of optimal resources for a species, they do not reveal the population size a landscape is capable of supporting--information that is often crucial for decision makers and managers. We used a new approach, "maximum clique analysis," to demonstrate how HS maps for territorial species can be used to estimate the carrying capacity, N(k), of a given landscape. We estimated the N(k) of Ovenbirds (Seiurus aurocapillus) and bobcats (Lynx rufus) in an 1153-km2 study area in Vermont, USA. These two species were selected to highlight different approaches in building an HS map as well as computational challenges that can arise in a maximum clique analysis. We derived 30-m2 HS maps for each species via occupancy modeling (Ovenbird) and by resource utilization modeling (bobcats). For each species, we then identified all pixel locations on the map (points) that had sufficient resources in the surrounding area to maintain a home range (termed a "pseudo-home range"). These locations were converted to a mathematical graph, where any two points were linked if two pseudo-home ranges could exist on the landscape without violating territory boundaries. We used the program Cliquer to find the maximum clique of each graph. The resulting estimates of N(k) = 236 Ovenbirds and N(k) = 42 female bobcats were sensitive to different assumptions and model inputs. Estimates of N(k) via alternative, ad hoc methods were 1.4 to > 30 times greater than the maximum clique estimate, suggesting that the alternative results may be upwardly biased. The maximum clique analysis was computationally intensive but could handle problems with < 1500 total pseudo-home ranges (points). Given present computational constraints, it is best suited for species that occur in clustered distributions (where the problem can be

  14. Delivering Transgenic DNA Exceeding the Carrying Capacity of AAV Vectors

    Science.gov (United States)

    Hirsch, Matthew L.; Wolf, Sonya J.; Samulski, R.J.

    2016-01-01

    Gene delivery using recombinant adeno-associated virus (rAAV) has emerged to the forefront demonstrating safe and effective phenotypic correction of diverse diseases including hemophilia B and Leber’s congenital amaurosis. In addition to rAAV’s high efficiency of transduction and the capacity for long-term transgene expression, the safety profile of rAAV remains unsoiled in humans with no deleterious vector-related consequences observed thus far. Despite these favorable attributes, rAAV vectors have a major disadvantage preventing widespread therapeutic applications; as the AAV capsid is the smallest described to date, it cannot package “large” genomes. Currently, the packaging capacity of rAAV has yet to be definitively defined but is approximately 5 kb, which has served as a limitation for large gene transfer. There are two main approaches that have been developed to overcome this limitation, split AAV vectors, and fragment AAV (fAAV) genome reassembly (Hirsch et al., Mol Ther 18(1):6–8, 2010). Split rAAV vector applications were developed based upon the finding that rAAV genomes naturally concatemerize in the cell post-transduction and are substrates for enhanced homologous recombination (HR) (Hirsch et al., Mol Ther 18(1):6–8, 2010; Duan et al., J Virol 73(1):161–169, 1999; Duan et al., J Virol 72(11):8568–8577, 1998; Duan et al., Mol Ther 4(4):383–391, 2001; Halbert et al., Nat Biotechnol 20(7):697–701, 2002). This method involves “splitting” the large transgene into two separate vectors and upon co-transduction, intracellular large gene reconstruction via vector genome concatemerization occurs via HR or nonhomologous end joining (NHEJ). Within the split rAAV approaches there currently exist three strategies: overlapping, trans-splicing, and hybrid trans-splicing (Duan et al., Mol Ther 4(4):383–391, 2001; Halbert et al., Nat Biotechnol 20(7):697–701, 2002; Ghosh et al., Mol Ther 16(1):124–130, 2008; Ghosh et al., Mol Ther 15

  15. 25 CFR 161.204 - How are carrying capacities and stocking rates established?

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false How are carrying capacities and stocking rates... WATER NAVAJO PARTITIONED LANDS GRAZING PERMITS General Provisions § 161.204 How are carrying capacities..., review and adjust the carrying capacity of each range unit by determining the number of livestock,...

  16. The information carrying capacity of a cosmological constant

    CERN Document Server

    Simidzija, Petar

    2016-01-01

    We analyze the exchange of information in different cosmological backgrounds when sender and receiver are timelike separated and communicate through massless fields (without the exchange of light-signals). Remarkably, we show that the dominance of a cosmological constant makes the amount of recoverable information imprinted in the field by the sender extremely resilient: it does not decay in time or with the spatial separation of sender and receiver, and it actually increases with the rate of expansion of the Universe. This is in stark contrast with the information carried by conventional light-signals and with previous results on timelike communication through massless fields in matter dominated cosmologies.

  17. Dynamic Carrying Capacity Analysis of Double-Row Four-Point Contact Ball Slewing Bearing

    Directory of Open Access Journals (Sweden)

    Yunfeng Li

    2015-01-01

    Full Text Available Carrying capacity is the most important performance index for slewing bearings. Maximizing the carrying capacity of slewing bearing is one pursuing goal for the bearing designer; this is usually realized by optimizing the design parameters. A method of analyzing the carrying capacity of double-row four-point contact ball slewing bearing by using dynamic carrying capacity surfaces was proposed in this paper. Based on the dynamic load carrying capacity surface of the slewing bearing, the effect of changes of the bearing design parameters, such as axial clearance, raceway groove radius coefficient, and contact angle, on the dynamic carrying capacity of the slewing bearing was researched; the trend and the degree of the effect of the micro changes of the bearing design parameters on the dynamic load carrying capacity of the bearing were discussed, and the results provide the basis for optimizing the design parameter of this type of slewing bearing.

  18. Disharmony between society and environmental carrying capacity: a historical review, with an emphasis on China.

    Science.gov (United States)

    Cao, Shixiong; Chen, Li; Liu, Zhande

    2007-07-01

    Nature can survive without humans, but humans cannot survive without nature. Despite a clear understanding of this dependency, humans continue to exist in disharmony with nature, and our current environmental and human dilemmas reflect old problems with a long history. Societies have historically experienced many transitions from harmony between nature and society to a crisis of disharmony, followed by a subsequent transition from crisis to harmony. Such ecological crises arise when society no longer practices sustainable consumption of resources within the limits imposed by the environmental carrying capacity. Over the long term, the growth in human desires has always exceeded the growth in the environmental carrying capacity. Science, technology, and social institutions must all be improved to resolve the ecological crises that arise from this imbalance. This paper discusses how increasing understanding of the problem by the public and by decision makers is the key to minimizing the undesirable impacts of the coming bottleneck for sustainable development. Furthermore, we emphasize how this awareness must be translated into fundamental political and economic changes.

  19. A model to estimate aquaculture carrying capacity in three areas of the Philippines

    Directory of Open Access Journals (Sweden)

    Tarzan Legović

    2008-12-01

    Full Text Available A model was developed to estimate the production carrying capacity of water bodies based on nutrient inputs from aquaculture and other sources, flushing rates, and the risk of algal blooms for three different areas of the Philippines – Bolinao (marine site, Dagupan (brackishwater site and Taal Lake (freshwater site. The results suggest that aquaculture production in the Taal Lake was greater than the sustainable carrying capacity. Aquaculture structures in Bolinao were close to carrying capacity during average tidal exchange but greater than the carrying capacity during low tidal exchange and no winds.Aquaculture production in the Dagupan estuary has not overcome its carrying capacity even during low flow. However, during very low flow and no tidal flushing, carrying capacity has been overcome.

  20. Synchronisation of fertility with carrying capacity; an investigation using classical and agent based modeling

    Directory of Open Access Journals (Sweden)

    Hugh Crozier Murrell

    2013-05-01

    Full Text Available A generalized Verhulst model subject to seasonal change in both fertility rate and carrying capacity is outlined. Numerical solutions to the Verhulst equations are employed to obtain optimal fertility rate phase shift with respect to carrying capacity. Possible natural selection for a preferred season of conception is investigated using agent based simulations. Both experiments indicate that synchronization of fertility rate to environment carrying capacity is beneficial to species survival.

  1. Research on Carrying Capacity of Water Resource Based on Multi-reservoir Regulation

    OpenAIRE

    Liu Renyuan; Li Lei; Li Hua; Huang Qiang

    2013-01-01

    Analyze the level of Carrying Capacity of Water Resources; evaluate the condition of e region social, economic and ecological environment comprehensive and sustainable development. This study is based on analyzing the meaning of water resources carrying capacity, take water resources of the Midwest of Shenzhen City an example., by the way of the “Coordinated and sustainable development” theory, found the model of the Carrying Capacity of Water Resources, Calculated and analyzed. Water efficie...

  2. Effects of a Fluctuating Carrying Capacity on the Generalized Malthus-Verhulst Model

    OpenAIRE

    Héctor Calisto; Chandía, Kristopher J.; Mauro Bologna

    2014-01-01

    We consider a generalized Malthus-Verhulst model with a fluctuating carrying capacity and we study its effects on population growth. The carrying capacity fluctuations are described by a Poissonian process with an exponential correlation function. We will find an analytical expression for the average of a number of individuals and show that even in presence of a fluctuating carrying capacity the average tends asymptotically to a constant quantity.

  3. Effects of a Fluctuating Carrying Capacity on the Generalized Malthus-Verhulst Model

    Directory of Open Access Journals (Sweden)

    Héctor Calisto

    2014-01-01

    Full Text Available We consider a generalized Malthus-Verhulst model with a fluctuating carrying capacity and we study its effects on population growth. The carrying capacity fluctuations are described by a Poissonian process with an exponential correlation function. We will find an analytical expression for the average of a number of individuals and show that even in presence of a fluctuating carrying capacity the average tends asymptotically to a constant quantity.

  4. Review on the Evaluation System of Public Safety Carrying Capacity about Small Town Community

    Institute of Scientific and Technical Information of China (English)

    Ming; SUN; Tianyu; ZHU

    2014-01-01

    Recently,small town community public safety problem has been increasingly highlighted,but its research is short on public safety carrying capacity. Through the investigation and study of community public safety carrying capacity,this paper analyzes the problem of community public safety in our country,to construct index evaluation system of public safety carrying capacity in small town community. DEA method is used to evaluate public safety carrying capacity in small town community,to provide scientific basis for the design of support and standardization theory about small town community in public safety planning.

  5. Risk Analysis on Groundwater Resources Carrying Capacity Based on Blind Number Theory

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji; YU Sujun

    2007-01-01

    Blind numbers of evaluation indices about groundwater resources carrying capacity are defined from the concomitancy of randomness, fuzziness, grey property and unascertainment of groundwater system.Based on fuzzy theory, a comprehensive evaluation model on groundwaterresources carrying capacity is constructed with blind information. Then arisk assessment model of surcharge about groundwater resources carryingcapacity is established on blind reliability theory. The probable value"*"'matrix of fuzzy membership degree about carrying capacity corresponding to each judgment level can be obtained with the aid of blind algorithm as well as the subjective reliability "×" matrix. And then a graph of"groundwater carrying capacity v.s. accumulative reliability" can be gained.Based on the graph, fuzzy membership degree of groundwater resourcescarrying capacity to each judgment level under different risk probabilitycan be got. Thus, a comparatively reasonable judgment to groundwaterresources carrying capacity might be obtained, with comprehensive analysis to the state of society, economy technology and ecology.

  6. Carry

    DEFF Research Database (Denmark)

    Koijen, Ralph S.J.; Moskowitz, Tobias J.; Heje Pedersen, Lasse;

    that include global equities, global bonds, currencies, commodities, US Treasuries, credit, and equity index options. This predictability underlies the strong returns to "carry trades" that go long high-carry and short low-carry securities, applied almost exclusively to currencies, but shown here...

  7. [Measuring water ecological carrying capacity with the ecosystem-service-based ecological footprint (ESEF) method: Theory, models and application].

    Science.gov (United States)

    Jiao, Wen-jun; Min, Qing-wen; Li, Wen-hua; Fuller, Anthony M

    2015-04-01

    Integrated watershed management based on aquatic ecosystems has been increasingly acknowledged. Such a change in the philosophy of water environment management requires recognizing the carrying capacity of aquatic ecosystems for human society from a more general perspective. The concept of the water ecological carrying capacity is therefore put forward, which considers both water resources and water environment, connects socio-economic development to aquatic ecosystems and provides strong support for integrated watershed management. In this paper, the authors proposed an ESEF-based measure of water ecological carrying capacity and constructed ESEF-based models of water ecological footprint and capacity, aiming to evaluate water ecological carrying capacity with footprint methods. A regional model of Taihu Lake Basin was constructed and applied to evaluate the water ecological carrying capacity in Changzhou City which located in the upper reaches of the basin. Results showed that human demand for water ecosystem services in this city had exceeded the supply capacity of local aquatic ecosystems and the significant gap between demand and supply had jeopardized the sustainability of local aquatic ecosystems. Considering aqua-product provision, water supply and pollutant absorption in an integrated way, the scale of population and economy aquatic ecosystems in Changzhou could bear only 54% of the current status.

  8. The application of a phosphorus mass balance model for estimating the carrying capacity of Lake Kariba

    OpenAIRE

    MHLANGA, Lindah; MHLANGA, Wilson; MWERA, Paul

    2013-01-01

    The aim of this study was to use an empirical mass balance equation to estimate the carrying capacity of Lake Kariba, where cage culture for Nile tilapia Oreochromis niloticus has been practiced since 1996. The carrying capacity for the lake was estimated at 33.2 × 103 t per year using the Dillon-Rigler phosphorus budget model.

  9. Phenomenological approach to describe logistic growth and carrying capacity-dependent growth processes

    Indian Academy of Sciences (India)

    DIBYENDU BISWAS; SWARUP PORIA; SANKAR NARAYAN PATRA

    2016-11-01

    In this communication, different classes of phenomenological universalities of carrying capacity dependent growth processes have been proposed. The logistic as well as carrying capacity-dependent West-type allometry-based biological growths can be explained in this proposed framework. It is shown that logistic and carrying capacity-dependent West-type growths are phenomenologically identical in nature. However, there is a difference between them in terms of coefficients involved in the phenomenological descriptions. Involuted Gompertz function, used to describe biological growth processes undergoing atrophy or a demographic and economic system undergoing involution or regression, can be addressed in this proposed environment-dependent description. It is also found phenomenologically that the energy intake of an organism depends on carrying capacity whereas metabolic cost does not depend on carrying capacity. In addition, some other phenomenologicaldescriptions have been examined in this proposed framework and graphical representations of variation of different parameters involved in the description are executed.

  10. Research on Carrying Capacity of Water Resource Based on Multi-reservoir Regulation

    Directory of Open Access Journals (Sweden)

    Liu Renyuan

    2013-12-01

    Full Text Available Analyze the level of Carrying Capacity of Water Resources; evaluate the condition of e region social, economic and ecological environment comprehensive and sustainable development. This study is based on analyzing the meaning of water resources carrying capacity, take water resources of the Midwest of Shenzhen City an example., by the way of the “Coordinated and sustainable development” theory, found the model of the Carrying Capacity of Water Resources, Calculated and analyzed. Water efficiency coefficients are different in different states, the Carrying Capacity of Water Resources is different too. the water resources in the Midwest of Shenzhen City can only meet now this stage (2010 Urban water demand, meanwhile people of over loading in there are also constantly increasing, In the future, Water requirement of Shenzhen Midwest cities must increase Dongjiang water and west diversion works of Shen Zhen, in order to enhance Carrying Capacity of Water Resources of the area.

  11. Comparative analysis of environmental carrying capacity of the Bohai Sea Rim area in China.

    Science.gov (United States)

    Lin, Lu; Liu, Yi; Chen, Jining; Zhang, Tianzhu; Zeng, Siyu

    2011-11-01

    Environmental carrying capacity is an essential metric for measuring regional sustainability. Although the term "carrying capacity" has been applied for over a century, the concept definition, quantitative methods and comprehensive evaluation remain arguable. This study analyzed the carrying capacity of four environmental elements, including water resources, air, surface water and offshore sea, and integrated them into a comprehensive index to represent overall regional profiles of resources and environment. The method was then applied to thirteen municipalities in the Bohai Sea Rim area, one of the most rapidly developing regions in transition China. The results show that the comprehensive environmental carrying capacity of the municipalities in the south sub-region were largest in 2007, while that of the west municipalities were lowest. The regional economic development exceeded the overall environmental carrying capacity by 36% and the west sub-region area deserves overwhelming attention for future industrial allocation.

  12. Estimating Recreational Carrying Capacity of Gheisary Protected Area in Chaharmahal & Bakhtiari Province

    OpenAIRE

    Sheikh, A; Jafari, A.; Setoodeh, A

    2014-01-01

    It is now certain that to ensure a long term sustainable development, protected areas, the favored destinations for ecotourism, required a well written planning management. Each destination however has limited capability which is called “carrying capacity” to invite visitors. Physical, real (ecological) and effective (manageable) are different kinds of carrying capacity. The current study presented these varieties of carrying capacities for Gheisary protected area, stretched over 10,000 ha in...

  13. Ecological Carrying Capacity in Beijing Mountainous Areas Taking Fangshan District as an Example

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] The aim was to investigate ecological carrying capacity of Fangshan District in Beijing. [Method] Ecological footprint and carrying capacity of Fangshan District in 2007 and 2008 were analyzed with ecological footprint model and the difference between ecological footprint and carrying capacity there was con- cluded. Furthermore, an assessment was made on relation between Fangshan de- velopment with local ecological carrying capacity to evaluate sustainable development of Fangshan District. [Result] Fangshan District is of lightly ecological deficit; ecologi- cal footprint per capita in 2007-2008 was deficit and tended to expand. Two meth- ods are available to reduce ecological :deficit, including reduction of ecological foot- print and increase of carrying capacity. In general, supply and demand of carrying capacity in Fangshan are better, though with some problems. It is necessary to fur- ther develop related industries to final eliminate ecological deficit in order to achieve ecological conservation-orientation and sustainable development of Fangshan District. [Conclusion] The research provides theoretical references for overall evaluation on eco- logical carrying capacity of Fangshan District.

  14. A Novel Evaluation algorithm of Urban Comprehensive Carrying Capacity Index System in Northwest China:Lanzhou city as a example

    Science.gov (United States)

    Li, Jing; Lei, Song; Ling, Ma

    2016-06-01

    With the rapid growth of the urban population and quick expansion of urban dimensions, the affecting urban development constraints of urban carrying capacity has increasingly been attracting people's attention. However, the effective synthesization of urban resources carrying capacity, urban environmental carrying capacity, economic carrying capacity, society carrying capacity and traffic carrying capacity hardly acted as an urban comprehensive carrying capacity evaluation system. In this paper, the novel comprehensive index system of urban resources carrying capacity, urban environmental carrying capacity, economic carrying capacity, society carrying capacity and traffic carrying capacity was used for analyzing and evaluating urban comprehensive carrying capacity. Firstly, the standardization of evaluation index was constructed in the urban comprehensive carrying capacity index system. In addition, the past decade data from 2002 to 2011 was analyzed and evaluated in the weighted index system. Finally, the influence mechanism of various carrying capacity factors on urban comprehensive carrying capacity was investigated in Lanzhou. Experimental results can be summarized that the variation tendency of urban comprehensive carrying capacity was the annual increase of levels and the promotion countermeasure was put forward with congenital restricting factors and acquired restricting factors.

  15. Impact of Flexibility Options on Grid Economic Carrying Capacity of Solar and Wind: Three Case Studies

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Novacheck, Joshua [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Lab. (NREL), Golden, CO (United States); O' Connell, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-12-01

    In this study, we attempt to quantify the benefits of various options of grid flexibility by measuring their impact on two measures: economic carrying capacity and system costs. Flexibility can increase economic carrying capacity and reduce overall system costs. In some cases, options that provide a limited increase in economic carrying capacity can provide significant operational savings, thus demonstrating the need to evaluate flexibility options using multiple metrics. The value of flexibility options varies regionally due to different generation mixes and types of renewables. The more rapid decline in PV value compared to wind makes PV more dependent on adding flexibility options, including transmission and energy storage.

  16. Quantifying spatially derived carrying capacity occupation: Framework for characterisation modelling and application to terrestrial acidification

    DEFF Research Database (Denmark)

    Bjørn, Anders; Margni, M.; Bulle, C.

    *year. This metric resembles that of the ecological footprint method and may be compared to the availability of land or water. The framework was applied to the terrestrial acidification impact category. The geochemical steady-state model PROFILE was used to quantify carrying capacities as deposition levels......The popularity of the ecological footprint method and the planetary boundaries concept shows an increasing interest among decision makers in comparing environmental impacts to carrying capacities of natural systems. Recently carrying capacity-based normalisation references were developed for impact...

  17. Evaluation on Population Carrying Capacity of Cultivated Land Based on Human - grain Relationship in Chengdu%基于人粮关系的成都市耕地资源人口承载力研究

    Institute of Scientific and Technical Information of China (English)

    吕秋俊; 李晓

    2016-01-01

    With the acceleration of urbanization process,the situation of cultivated land resources in Chengdu city has changed significantly,and the food security has become increasingly prominent. Combined with the characteristics of the dynamic changes of the actual cultivated land resources,grain and population in 2003 ~2012 in Chengdu,this paper analyzes the productive potential of cultivated land resources and population carrying capacity of land resources, aiming at 2016 ~ 2020,using GM(1,1)grey system forecasting model to predict the development tendency of culti-vated land area,per unit area yield of grain and population,etc. According to the three consumption levels of saturat-ed,comparatively well - off and surplus,the population supporting capacity of land resources in forecasted years have been discussed. Finally,some countermeasures are put forward to enhance the population supporting capacity of land resources and achieve the sustainable development of cultivated land resources.%随着城镇化进程加快,成都市耕地资源现状发生显著变化,粮食安全问题日益凸显。结合成都市2003-2012年耕地资源、粮食与人口动态变化特点,分析其现实耕地资源生产潜力和人口承载力;以2016-2020年为目标年,运用 GM(1,1)灰色系统预测模型对耕地面积、粮食单产、人口等的发展趋势进行预测;并结合温饱型、小康型与富裕型三种不同的粮食消费标准对预测年份内耕地资源的人口承载力状况进行分析。最后提出了提高人口承载力、实现耕地资源可持续发展的对策与措施。

  18. Carrying Capacity Model Applied to Coastal Ecotourism of Baluran National Park, Indonesia

    Science.gov (United States)

    Armono, H. D.; Rosyid, D. M.; Nuzula, N. I.

    2017-07-01

    The resources of Baluran National Park have been used for marine and coastal ecotourism. The increasing number of visitors has led to the increasing of tourists and its related activities. This condition will cause the degradation of resources and the welfare of local communities. This research aims to determine the sustainability of coastal ecotourism management by calculating the effective number of tourists who can be accepted. The study uses the concept of tourism carrying capacity, consists the ecological environment, economic, social and physical carrying capacity. The results of the combined carrying capacity analysis in Baluran National Park ecotourism shows that the number of 3.288 people per day (151.248 tourists per year) is the maximum number of accepted tourists. The current number of tourist arrivals is only 241 people per day (87.990 tourists per year) which is far below the carrying capacity.

  19. Spawner-recruit relationships and fish stock carrying capacity in aquatic ecosystems

    DEFF Research Database (Denmark)

    MacKenzie, Brian; Myers, R.A.; Bowen, K.G.

    2003-01-01

    Few marine ecologists have addressed important questions about the relative productivity and carrying capacity of different ecosystems required to support fish populations. Whereas many researchers have investigated interannual variability in recruitment within a stock, we asked whether...

  20. Recreation carrying capacity estimations to support beach management at Praia de Faro, Portugal

    OpenAIRE

    Zacarias, D. A.; Williams, Allan T.; Newton, Alice

    2011-01-01

    The purpose of this research paper is to outline the theory and practice of tourism carrying capacity assessment and its relevance as a management tool for coastal management. Based on the Tourism Carrying Capacity Assessment for Protected Areas Framework and the Image Capture Technique associated with the PAOT (people at one time) approach, this paper explores Praia de Faro as the study area and attempts to assess the optimum number of people that should be allowed without jeopar...

  1. Theoretical Research of the Urban Comprehensive Carrying Capacity in the Epoch of Urbanization

    OpenAIRE

    Li Changliang; Lian Lina

    2012-01-01

    Conventional wisdom suggests that ecological factors are prominent constraints of cities in the urbanization process. By contrast, this article provides a fresh conception of the urban comprehensive carrying capacity in the context of ecosystem, economy and social dimensions. Based on in-depth analysis, the author makes out a list of informative area-based indicators in three differentiated layers and the findings are that the urban comprehensive carrying capacity is an entanglement of three ...

  2. Noise-Induced Transitions in a Population Growth Model Based on Size-Dependent Carrying Capacity

    Directory of Open Access Journals (Sweden)

    Neeme Lumi

    2014-01-01

    Full Text Available The stochastic dynamics of a population growth model with size-dependent carrying capacity is considered. The effect of a fluctuating environment on population growth is modeled as a multiplicative dichotomous noise. At intermediate values of population size the deterministic counterpart of the model behaves similarly to the Von Foerster model for human population, but at small and very large values of population size substantial differences occur. In the stochastic case, an exact analytical solution for the stationary probability distribution is found. It is established that variation of noise correlation time can cause noise-induced transitions between three different states of the system characterized by qualitatively different behaviors of the probability distributions of the population size. Also, it is shown that, in some regions of the system parameters, variation of the amplitude of environmental fluctuations can induce single unidirectional abrupt transitions of the mean population size.

  3. The Carrying Capacity of Public Wild Land Recreation Areas: Evaluation of Alternative Measures

    Science.gov (United States)

    Greist, David A.

    1976-01-01

    Carrying capacity (the use level at which total satisfactions or benefits are mazimized) is not equatable to highest-use levels, since some visitors to recreational areas desire solitude and undisturbed environment--for these, an alternative definition for "capacity" should take into consideration the use level demanded after considering costs.…

  4. Localization capacity of human listeners

    DEFF Research Database (Denmark)

    Hammershøi, Dorte

    2009-01-01

    For some scenarios and situations, successful localization of the sound is vital for the hearing experience. One aspect of this is the natural limits of the human localization capacity, incl. dependence on e.g. direction and distance. When addressed in laboratory experiments, the significance...... of other modalities are controlled in different ways, yet figures will inherently reflect properties of the test situation as well as the capacity of the individual. The present paper will review some contemporary localization experiments, with a specific view to the "absolute" acuity, the measures used...

  5. Conceptual Framework of Tourism Carrying Capacity for a Tourism City: Experiences from National Parks in the United States

    Institute of Scientific and Technical Information of China (English)

    Zheng Nasha; Zheng Xilai

    2010-01-01

    There is no universally-accepted definition of tourism carrying capacity(TCC).Numerical TCC focuses on use level and is considered as"a magic number"of the saturation point for tourism.There are several reasons why numerical tourism capacity is inadequate.Alternatively,tourism capacity can be defined in terms of limits of acceptable change,which shifts the focus from"how much use is too much"to"how much change is acceptable".This article proposes an improved conceptual framework for evaluating carrying capacity for the tourism city based on approaches used in US national parks,which consider the impact of human use on a city's economic,environmental/resource,and socio-cultural conditions.Based on the basic data of indicator values and relevant standards,the framework monitors the current indicators and predicts future indicator values; it can also be used to assess and predict TCC.

  6. Introducing carrying capacity-based normalisation in LCA: framework and development of references at midpoint level

    DEFF Research Database (Denmark)

    Bjørn, Anders; Hauschild, Michael Zwicky

    2015-01-01

    capacity of a reference region divided by its population and thus describes the annual personal share of the carrying capacity.The developed references can be applied to indicator results obtained using commonly applied characterisation models in LCIA. The European NR are generally lower than the global NR...... ozone formation and soil quality were found to exceed carrying capacities several times.The developed carrying capacity-based normalisation references offer relevant supplementary reference information to the currently applied references based on society’s background interventions by supporting...... an evaluation of the environmental sustainability of product systems on an absolute scale.Challenges remain with respect to spatial variations to increase the relevance of the normalisation references for impact categories that function at the local or regional scale. The sensitivity of NR to different choices...

  7. The study of environmental carrying capacity for sustainable tourism in Telaga Warna Telaga Pengilon Nature Park, Dieng Plateu, Central Java

    Science.gov (United States)

    Melat Aryasa, Alexander; Nur Bambang, Azis; Muhammad, Fuad

    2017-06-01

    The increasing in quantity of the tourists visiting Telaga Warna Telaga Pengilon Nature Park, Dieng Plateau, Central Java, can cause a potential threat toward the conservation sustainability of the tourist attraction and the surrounding area. The utilization of conservation area for tourist attraction has to be carried out based on the principal of Environmental Carrying Capacity so that it will not affect the ecosystem. This study aims to determine the value of Telaga Warna Telaga Pengilon Nature Park environmental carrying capacity as a conservation area used for tourism activities. The environmental carrying capacities calculated in this study were physical carrying capacity, real carrying capacity, and effective carrying capacity. Results of this research show that the physical carrying capacity of The Telaga Warna Telaga Pengilon Nature Park was 31,302 visitors, the real capacity was 869 visitors/day and the effective carrying capacity was 579 visitors/day. Thus, the sustainable tourism development strategy is needed to manage the everlasting natural resources.

  8. Measurement and assessment of carrying capacity of the environment in Ningbo, China.

    Science.gov (United States)

    Liu, R Z; Borthwick, Alistair G L

    2011-08-01

    Carrying Capacity of the Environment (CCE) provides a useful measure of the sustainable development of a region. Approaches that use integrated assessment instead of measurement can lead to misinterpretation of sustainable development because of confusion between Environmental Stress (ES) indexes and CCE indexes, and the selection of over-simple linear plus models. The present paper proposes a comprehensive measurement system for CCE which comprises models of natural resources capacity, environmental assimilative capacity, ecosystem services capacity, and society supporting capacity. The corresponding measurable indexes are designed to assess CCE using a carrying capacity surplus ratio model and a vector of surplus ratio of carrying capacity model. The former aims at direct comparison of ES and CCE based on the values of basic indexes, and the latter uses a Euclidean vector to assess CCE states. The measurement and assessment approaches are applicable to Strategic Environmental Assessment (SEA) and environmental planning and management. A case study is presented for Ningbo, China, whereby all the basic indexes of ECC are measured and the CCE states assessed for 2005 and 2010.

  9. Evaluation of Ecological Carrying Capacity of Henan Province under the Sustainable Development

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Based on the overview of social economy of Henan Province,I probe into the concept and evaluation of ecological carrying capacity.By using the ecological footprint analysis and the data of various kinds of land supply of Henan Province from 2000 to 2008,the ecological carrying capacity of Henan Province is analyzed.It is unveiled that inharmonious population,natural resources and economic resources affect the efficiency of the sustainable development of ecological carrying capacity of Henan Province;the underdeveloped economy of Henan Province impacts the sustainable development of ecological carrying capacity of Henan Province and the overburdened population lead to the insufficiency of ecological carrying capacity.Around protecting the threshold of ecological system,the countermeasures are put forward,which cover forming the idea of ecological economy and circular economy and promoting the transformation of economy growth mode;taking the development road of using resources intensively and performing the strategy of sustainable utilization of resources;strictly control population growth and strengthening people’s crisis awareness of resources and environment.

  10. Variation in local carrying capacity and the individual fate of bacterial colonizers in the phyllosphere.

    Science.gov (United States)

    Remus-Emsermann, Mitja N P; Tecon, Robin; Kowalchuk, George A; Leveau, Johan H J

    2012-04-01

    Using a phyllosphere model system, we demonstrated that the term 'carrying capacity', as it is commonly used in microbial ecology, needs to be understood as the sum of many 'local carrying capacities' in order to better explain and predict the course and outcome of bacterial colonization of an environment. Using a green fluorescent protein-based bioreporter system for the quantification of reproductive success (RS) in individual Erwinia herbicola cells, we were able to reconstruct the contribution of individual immigrants to bacterial population sizes on leaves. Our analysis revealed that plant foliage represents to bacteria an environment where individual fate is determined by the local carrying capacity of the site where an immigrant cell lands. With increasing inoculation densities, the RS of most immigrants declined, suggesting that local carrying capacity under the tested conditions was linked to local nutrient availability. Fitting the observed experimental data to an adapted model of phyllosphere colonization indicated that there might exist three types of sites on leaves, which differ in their frequency of occurrence and local carrying capacity. Specifically, our data were consistent with a leaf environment that is characterized by few sites where individual immigrants can produce high numbers of offspring, whereas the remainder of the leaf offered an equal number of sites with low and medium RS. Our findings contribute to a bottom-up understanding of bacterial colonization of leaf surfaces, which includes a quantifiable role of chance in the experience at the individual level and in the outcome at the population level.

  11. Modelling of carrying capacity in National Park - Fruška Gora (Serbia case study

    Directory of Open Access Journals (Sweden)

    Vujko Aleksandra

    2017-03-01

    Full Text Available Negative effects of tourism development in a destination are usually the consequence of the high concentration of tourists, accommodation facilities and the activities that are practiced in a relatively restricted area. One of the most important measures to protect the areas is to calculate the maximum number of tourists that can simultaneously reside in a region, i.e. the determination of the carrying capacity. This paper outlines a method for determining carrying capacity based on zoning of environmental resources and zoning within a region. The paper argues for a return to the idea of identifying maximum appropriate number of users. The main hypothesis of the paper is based on the statement that the development of tourism in Fruška Gora (Mountain National Park in Northern Serbia must be in accordance with the basic principles of sustainability, including the determination of carrying capacity. The main research goal was to show the opinion of local residents about the uncontrolled development of tourism, and to determine the carrying capacity in four sports and recreational zones of the mountain. The carrying capacity of the area is calculated by Lavery and Stanev formulas.

  12. The evolution of carrying capacity in constrained and expanding tumour cell populations.

    Science.gov (United States)

    Gerlee, Philip; Anderson, Alexander R A

    2015-08-12

    Cancer cells are known to modify their micro-environment such that it can sustain a larger population, or, in ecological terms, they construct a niche which increases the carrying capacity of the population. It has however been argued that niche construction, which benefits all cells in the tumour, would be selected against since cheaters could reap the benefits without paying the cost. We have investigated the impact of niche specificity on tumour evolution using an individual based model of breast tumour growth, in which the carrying capacity of each cell consists of two components: an intrinsic, subclone-specific part and a contribution from all neighbouring cells. Analysis of the model shows that the ability of a mutant to invade a resident population depends strongly on the specificity. When specificity is low selection is mostly on growth rate, while high specificity shifts selection towards increased carrying capacity. Further, we show that the long-term evolution of the system can be predicted using adaptive dynamics. By comparing the results from a spatially structured versus well-mixed population we show that spatial structure restores selection for carrying capacity even at zero specificity, which poses a solution to the niche construction dilemma. Lastly, we show that an expanding population exhibits spatially variable selection pressure, where cells at the leading edge exhibit higher growth rate and lower carrying capacity than those at the centre of the tumour.

  13. Modelling of carrying capacity in National Park - Fru\\vska Gora (Serbia) case study

    Science.gov (United States)

    Vujko, Aleksandra; Plavša, Jovan; Petrović, Marko D.; Radovanović, Milan; Gajić, Tamara

    2017-03-01

    Negative effects of tourism development in a destination are usually the consequence of the high concentration of tourists, accommodation facilities and the activities that are practiced in a relatively restricted area. One of the most important measures to protect the areas is to calculate the maximum number of tourists that can simultaneously reside in a region, i.e. the determination of the carrying capacity. This paper outlines a method for determining carrying capacity based on zoning of environmental resources and zoning within a region. The paper argues for a return to the idea of identifying maximum appropriate number of users. The main hypothesis of the paper is based on the statement that the development of tourism in Fru\\vska Gora (Mountain) National Park in Northern Serbia must be in accordance with the basic principles of sustainability, including the determination of carrying capacity. The main research goal was to show the opinion of local residents about the uncontrolled development of tourism, and to determine the carrying capacity in four sports and recreational zones of the mountain. The carrying capacity of the area is calculated by Lavery and Stanev formulas.

  14. An Alternative Approach for High Speed Railway Carrying Capacity Calculation Based on Multiagent Simulation

    Directory of Open Access Journals (Sweden)

    Mo Gao

    2016-01-01

    Full Text Available It is a multiobjective mixed integer programming problem that calculates the carrying capacity of high speed railway based on mathematical programming method. The model is complex and difficult to solve, and it is difficult to comprehensively consider the various influencing factors on the train operation. The multiagent theory is employed to calculate high speed railway carrying capacity. In accordance with real operations of high speed railway, a three-layer agent model is developed to simulate the operating process of high speed railway. In the proposed model, railway network agent, line agent, station agent, and train agent are designed, respectively. To validate the proposed model, a case study is performed for Beijing–Shanghai high speed railway by using NetLogo software. The results are consistent with the actual data, which implies that the proposed multiagent method is feasible to calculate the carrying capacity of high speed railway.

  15. Estimating the carrying capacity of green mussel cultivation by using net nutrient removal model.

    Science.gov (United States)

    Srisunont, Chayarat; Babel, Sandhya

    2016-11-15

    This study aims to evaluate the nutrient removal potential and carrying capacity of green mussel cultivation by using the mass balance model. The developed model takes into consideration the green mussel growth rate, density and chlorophyll a concentration. The data employed in this study were based on culture conditions at Sriracha Fisheries Research Station, Thailand. Results show that net nutrient removal by green mussel is 3302, 380, and 124mg/year/indv for carbon, nitrogen, and phosphorus respectively. The carrying capacity of green mussel cultivation was found to be 300indv/m(2) based on chlorophyll a concentration which will not release phosphorus in the water environment beyond the standard (45μg-PO4(-3)-P/L). Higher chlorophyll a concentration results in lowered green mussel carrying capacity. This model can assist farm operators with possible management strategies for a sustainable mussel cultivation and protection of the marine environment.

  16. Conditions for the management of carrying capacity in the parks of Parks&Benefits

    DEFF Research Database (Denmark)

    Brandt, Jesper; Holmes, Esbern

    2011-01-01

    Growth in the number of visitors is an upcoming problem in nature parks. Nature parks are at the same time facing increasing demand, falling public appropriations and receding focus on their conservation functions. To ensure a balancing of nature protection and economic utilization the concept...... of carrying capacity has received increasing attention among park-authorities all over the world. Carrying capacities understood as limits or standards not to be exceeded to protect a supporting landscape system are not scientifically determined sizes. They are a result of political decision processes among...... stakeholders, balancing use and protection preferably based on scientific and/or experiential cognition. The conditions for the management of carrying capacity for the 8 nature parks in the EC Baltic Project Parks&Benefits are analysed in the report. 1. Part focus on the methodology, concentrated...

  17. Self-adjustment of Carrying Capacity of Concrete Embedded with CFRC

    Institute of Scientific and Technical Information of China (English)

    Wu YAO

    2006-01-01

    By heating up the embedded carbon fiber reinforced cement based material (CFRC), the carrying capacity and deformation of concrete member could be adjusted. The relationship between temperature difference and expansion strain of CFRC was demonstrated, and the temperature-deformation-load effect of concrete embedded with CFRC was studied. Heating the CFRC up to different temperatures resulted in different degree of inner pre-stress in concrete. Thus, the load capacity of concrete could be regulated owing to counteracting the pre-stress.

  18. Carrying capacity for the electromagnetic suspension low-speed maglev train on the horizontal curve

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Aiming at the lateral dislocation between the electromagnets and the rails on a horizontal curve,we investigated a single magnetic bogie of the maglev train in this paper.The magnetic levitation and guidance forces supplied by the suspension modules were deduced by the flux tube method.According to the dynamic equilibrium equations of the maglev train on the curved track with cant,several major factors that influence the carrying capacity were analyzed,and the formula of the carrying capacity was presented.The results provide a theoretical reference for the design of maglev train.

  19. Evaluating the Carrying Capacity in The Škocjan Caves, Slovenia

    Science.gov (United States)

    Debevec Gerjevic, V.

    2009-04-01

    Park Škocjanske jame, Slovenija is a multidesignation site, located in south western part of Slovenia. In 1986 the Škocjanske jame - Škocjan Caves were listed in UNESCO world heritage list, in 1996 the Government of Republic Slovenia established the Regional Park Škocjanske jame, Slovenija. In 1999 the underground course of The Reka River in Škocjan Caves was designated a Ramsar site as first underground wetland of international importance. The park lies within three locations Natura 2000. In 2004 Park Škocjanske jame became a MAB locality as The Karst Biosphere Reserve. The tourist activity was already developed in the early 19th century. Today's research projects are focused on quality of caves microclimate, in order to enable the cave to remain as pristine as possible due to tourism and on the other hand to provide safe environment for people who work in the caves, and on quality of the water that flows from buffer zone to the underground world an then to the sea in Italy. The tourist activity increased during the past years. With the aim of nature conservation and protection the management plan was developed and special programme of monitoring started in order to detect changes in the environment due to the anthropogenic impact. In the park we consider the estimation of the carrying capacity as a key element for preparation of proper management guidelines for the tourism development in site. The caves system is rich in several halls and tunnels and distinguishes the caves for its variety of dimensions. There are several limitations of the visits and number of visitors. They merely depend on spatial characteristic of the caves and its surroundings and on human resources of the experts stuff that is in charge of guiding tourists groups to the caves. There is no simple formula that could be used for evaluation of capacity on general, but detailed studies of several locations and suitable description of parameters could give us an idea of proposing the

  20. Comprehensive Measurement for Carrying Capacity of Resources and Environment of City Clusters in Central China

    Institute of Scientific and Technical Information of China (English)

    FANG Chuanglin; LIU Xiaoli

    2010-01-01

    Studying the carrying capacity of resources and environment of city clusters in the central China has impor-tant practical guidance significance for promoting the healthy,sustainable and stable development of this region.Ac-cording to their influencing factors and reciprocity mechanism,using system dynamics approaches,this paper built a SD model for measuring the carrying capacity of resources and environment of the city clusters in the central China,and through setting different development models,the comprehensive measurement analysis on the carrying capacity was carried out.The results show that the model of promoting socio-economic development under the protection of resources and environment is the optimal model for promoting the harmony development of resources,environment,society and economy in the city clusters.According to this model,the optimum population scale of the city clusters in2020 is 42.80×106 persons,and the moderate economic development scale is 22.055× 1012 yuan(RMB).In 1996-2020,the carrying capacity of resources and environment in the city clusters took on obvious phase-change characteristics.During the studied period,it is basically at the initial development stage,and will come through the development process from slow development to speedup development.

  1. Factors affecting the environmental carrying capacity of a freshwater tropical lake system.

    Science.gov (United States)

    Mullakkezhil Reghunathan, Vishnuprasad; Joseph, Sabu; Warrier, C Unnikrishnan; Hameed, A Shahul; Albert Moses, Sheela

    2016-11-01

    Environmental carrying capacity is a measure of competence of a lake to accommodate pollution inputs without degrading water quality. In the research reported here, we identified the factors influencing the environmental carrying capacity of Vellayani Lake or VL (a typical tropical freshwater lake), Thiruvananthapuram, Kerala State, India. R-mode factor analysis is used to identify the factors controlling the carrying capacity of the lake, whereas hierarchical cluster analysis (HCA) helped to classify the lake. The carrying capacity of the lake is low with respect to alkalinity, due to ion deficiency, and is potentially reactive to sudden changes in pH. Eutrophic condition exists in the entire lake system. Acidic factor, mineralization factor, fertilizer factor (P & K), evaporation factor and organic pollution factor are the controllers of VL water quality during the pre-monsoon period. The same factors (but not evaporation factor) and an additional runoff factor control the water quality during monsoon. In the post-monsoon, the aforesaid factors (other than runoff, alkalinity) and soil erosion factor influence the water quality. Hence, managers of the lake system need to also focus on combating acidic factor during pre- and post-monsoons and runoff during monsoon. Smaller areal extent and shallow depth of VL, reduced outflow from it, less rainfall, presence of lateritic rock and soil and absence of limestone strata in the catchment are the chief elements affecting the acidic factor of Vellayani Lake.

  2. EFFICIENT, INTEGRATED TRANSPORT SYSTEM KEY TO PORT'S SUCCESS:Houston Sufficient support infrastructure, carrying capacity needed

    Institute of Scientific and Technical Information of China (English)

    ALAN DANIELS

    2005-01-01

    @@ An efficient, integrated transport system iskey to the Port of Vancouver s success. "There are many ways that we can optimizethe efficiency and carrying capacity of ourtransportation infrastructure in Canada: throughtechnology, by working together, by thinkingdifferently," said Captain Gordon Houston,President & CEO of the Vancouver Port Authority.

  3. Fuzzy Comprehensive Evaluation Model for Water Resources Carrying Capacity in Tarim River Basin, Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    MENG Lihong; CHEN Yaning; LI Weihong; ZHAO Ruifeng

    2009-01-01

    This paper explores the method of comprehensive evaluation of water resources carrying capacity and sets up an evaluation model applying the fuzzy comprehensive evaluation method. Based on the data of nature, society, economics and water resources of the Tarim River Basin in 2002, we evaluated the water resources carrying capacity of the basin by means of the model. The results show that the comprehensive grades are 0.438 and 0.454 for Aksu and Kashi prefectures respectively, where the current water resources exploitation and utilization has reached a relative high degree and there is only a very limited water carrying capacity, 0.620 for Kizilsu Kirgiz Autonomous Prefecture, where water resources carrying capacity is much higher, and in between for Hotan Prefecture and Bayingolin Mongolian Autonomous Prefecture. As a whole, the comprehensive grade of the Tarim River Basin is 0.508 and the current water resources exploitation and utilization has reached a relative high degree. Thus, we suggest that the integrated management of the water resources in the basin should be strengthened in order to utilize water resources scientifically and sustainably.

  4. Enhanced load-carrying capacity of hairy surfaces floating on water.

    Science.gov (United States)

    Xue, Yahui; Yuan, Huijing; Su, Weidong; Shi, Yipeng; Duan, Huiling

    2014-05-08

    Water repellency of hairy surfaces depends on the geometric arrangement of these hairs and enables different applications in both nature and engineering. We investigate the mechanism and optimization of a hairy surface floating on water to obtain its maximum load-carrying capacity by the free energy and force analyses. It is demonstrated that there is an optimum cylinder spacing, as a result of the compromise between the vertical capillary force and the gravity, so that the hairy surface has both high load-carrying capacity and mechanical stability. Our analysis makes it clear that the setae on water striders' legs or some insects' wings are in such an optimized geometry. Moreover, it is shown that surface hydrophobicity can further increase the capacity of a hairy surface with thick cylinders, while the influence is negligible when the cylinders are thin.

  5. Carrying capacities for nature parks as engines for sustainable regional development

    DEFF Research Database (Denmark)

    Brandt, Jesper; Holmes, Esbern

    of national and nature parks. Nature parks should rather develop towards a status as 'Biosphere Reserves' representing models for regional development, land use and landscape design in general. A relevant zoning of the regional environment of the Parks will be included as an instrument for such a strategy.......Growth in the number of visitors is an upcoming problem in nature parks. Nature parks are at the same time facing increasing demand, falling public appropriations and receding focus on their conservation functions. To ensure a balancing of nature protection and economic utilization the concept...... of carrying capacity has received increasing attention among park-authorities all over the world. A comparative analysis of conditions and initiatives related to visitor/nature carrying capacities in 8 nature parks in the Baltic region has been carried out. All the parks are candidates for recognition...

  6. Estimating a Global Hydrological Carrying Capacity Using GRACE Observed Water Stress

    Science.gov (United States)

    An, K.; Reager, J. T.; Famiglietti, J. S.

    2013-12-01

    Global population is expected to reach 9 billion people by the year 2050, causing increased demands for water and potential threats to human security. This study attempts to frame the overpopulation problem through a hydrological resources lens by hypothesizing that observed groundwater trends should be directly attributed to human water consumption. This study analyzes the relationships between available blue water, population, and cropland area on a global scale. Using satellite data from NASA's Gravity Recovery and Climate Experiment (GRACE) along with land surface model data from the Global Land Data Assimilation System (GLDAS), a global groundwater depletion trend is isolated, the validity of which has been verified in many regional studies. By using the inherent distributions of these relationships, we estimate the regional populations that have exceeded their local hydrological carrying capacity. Globally, these populations sum to ~3.5 billion people that are living in presently water-stressed or potentially water-scarce regions, and we estimate total cropland is exceeding a sustainable threshold by about 80 million km^2. Key study areas such as the North China Plain, northwest India, and Mexico City were qualitatively chosen for further analysis of regional water resources and policies, based on our distributions of water stress. These case studies are used to verify the groundwater level changes seen in the GRACE trend . Tfor the many populous, arid regions of the world that have already begun to experience the strains of high water demand.he many populous, arid regions of the world have already begun to experience the strains of high water demand. It will take a global cooperative effort of improving domestic and agricultural use efficiency, and summoning a political will to prioritize environmental issues to adapt to a thirstier planet. Global Groundwater Depletion Trend (Mar 2003-Dec 2011)

  7. Train Headway Models and Carrying Capacity of Super-Speed Maglev System

    Science.gov (United States)

    He, Shiwei; Song, Rui; Eastham, Tony

    Train headway models are established by analyzing the operation of the Transrapid Super-speed Maglev System (TSMS). The variation in the minimum allowable headway for trains of different speeds and consists is studied under various operational constraints. A potential Beijing-Shanghai Maglev line is used as an illustration to undertake capacity analyses with the model and methods. The example shows that the headway models for analyzing the carrying capacity of Maglev systems are very useful for the configurational design of this new transport system.

  8. Test-retest reliability of lifting and carrying in a 2-day functional capacity evaluation.

    Science.gov (United States)

    Reneman, M F; Dijkstra, P U; Westmaas, M; Göeken, L N H

    2002-12-01

    The objectives of this study were to establish test-retest reliability of lifting and carrying of a functional capacity evaluation (FCE) on two consecutive days and to verify the need for a 2-day protocol. A cohort of 50 patients (39 men, 11 women) with nonspecific low back pain were evaluated using a 2-day FCE protocol. Intraclass correlation coefficients (ICC) were calculated for weight lifted and carried. Predictive relationships between test and retest were explored by means of a regression analysis. The results of ICC were lifting low 0.87, lifting overhead 0.87, and carrying 0.77. Performances on day 2 were on an average 6-9% higher. Other than the amount of weight handled on day 1, no variable was found to predict performance on day 2. It was concluded that test-retest reliability of lifting and carrying was good, and the need for a 2-day protocol could not be confirmed.

  9. Assessing the Social Carrying Capacity of Diving Sites in Mabul Island, Malaysia

    Science.gov (United States)

    Zhang, Liye; Chung, ShanShan

    2015-12-01

    This study has explored social carrying capacity of an underwater environment based on divers' perceived crowding. Two dimensions were assessed, the number of divers seen and the proximity of diver. Data were obtained from a survey of 132 divers dived in Mabul Island, Malaysia during 2013-2014. Photographs depicting four levels of diver number and four levels of diver proximity in different combinations were shown to the respondents for assessing their acceptability. Between the two variables, the "number of divers" was the most influential factor for divers' perceived crowding. Divers would start to feel unacceptably crowded if 8-9 divers were visible to them at one time. Based on this, it is likely that the use level of diving sites in Mabul Island has already exceeded its social carrying capacity. Implications for future research and diving tourism management for Mabul Island are also discussed in the paper.

  10. Evaluation of Social Carrying Capacity of Topkapi Palace By Employees and Visitors

    Directory of Open Access Journals (Sweden)

    Kurban Ünlüönen

    2009-09-01

    Full Text Available Visitors’ using attraction resources at an optimum level is essential for the sustainable usage of areas. In fact Topkapı Palace arouses a considerable level of interest in terms of resources it has and this interest consequently leads to a concentration of visitors and a high degree of usage. The concentration in the area has utmost importance in terms of visitor carrying capacity. One of the groups who can evaluate the concentration present in this area most efficiently is the employees of the palace who are in continuous interaction with the visitors. One of the main objectives of this study is revealing the opinions of the employees on visitor carrying capacity. In order to gather information from the employees, face-to-face interview technique has been used and the evaluations of the employees have shown that visitor concentration has reached a level which may cause some negative results.

  11. Superior Current Carrying Capacity of Boron Nitride Encapsulated Carbon Nanotubes with Zero-Dimensional Contacts.

    Science.gov (United States)

    Huang, Jhao-Wun; Pan, Cheng; Tran, Son; Cheng, Bin; Watanabe, Kenji; Taniguchi, Takashi; Lau, Chun Ning; Bockrath, Marc

    2015-10-14

    We report fabrication and characterization of hexagonal boron nitride (hBN)-encapsulated carbon nanotube (CNT) field effect transistors, which are coupled to electrical leads via zero-dimensional contacts. Device quality is attested by the ohmic contacts and observation of Coulomb blockade with a single periodicity in small bandgap semiconducing nanotubes. Surprisingly, hBN-encapsulated CNT devices demonstrate significantly enhanced current carrying capacity; a single-walled CNT can sustain >180 μA current or, equivalently, a current density of ∼2 × 10(10) A/cm(2), which is a factor of 6-7 higher than devices supported on SiO2 substrates. Such dramatic enhancement of current carrying capacity arises from the high thermal conductivity of hBN and lower hBN-CNT interfacial thermal resistance and has implications for carbon electronic applications.

  12. An innovative method for water resources carrying capacity research--Metabolic theory of regional water resources.

    Science.gov (United States)

    Ren, Chongfeng; Guo, Ping; Li, Mo; Li, Ruihuan

    2016-02-01

    The shortage and uneven spatial and temporal distribution of water resources has seriously restricted the sustainable development of regional society and economy. In this study, a metabolic theory for regional water resources was proposed by introducing the biological metabolism concept into the carrying capacity of regional water resources. In the organic metabolic process of water resources, the socio-economic system consumes water resources, while products, services and pollutants, etc. are output. Furthermore, an evaluation index system which takes into the characteristics of the regional water resources, the socio-economic system and the sustainable development principle was established based on the proposed theory. The theory was then applied to a case study to prove its availability. Further, suggestions aiming at improving the regional water carrying capacity were given on the basis of a comprehensive analysis of the current water resources situation.

  13. Assessing the Social Carrying Capacity of Diving Sites in Mabul Island, Malaysia.

    Science.gov (United States)

    Zhang, Liye; Chung, ShanShan

    2015-12-01

    This study has explored social carrying capacity of an underwater environment based on divers' perceived crowding. Two dimensions were assessed, the number of divers seen and the proximity of diver. Data were obtained from a survey of 132 divers dived in Mabul Island, Malaysia during 2013-2014. Photographs depicting four levels of diver number and four levels of diver proximity in different combinations were shown to the respondents for assessing their acceptability. Between the two variables, the "number of divers" was the most influential factor for divers' perceived crowding. Divers would start to feel unacceptably crowded if 8-9 divers were visible to them at one time. Based on this, it is likely that the use level of diving sites in Mabul Island has already exceeded its social carrying capacity. Implications for future research and diving tourism management for Mabul Island are also discussed in the paper.

  14. Land Potential Productivity and Population Carrying Capacity of Yan’an City

    Institute of Scientific and Technical Information of China (English)

    Xiaoling; LIU; Wei; ZHANG

    2013-01-01

    The productivity attenuation method is adopted to calculate land potential productivity of counties of Yan’an City and calculate population carrying capacity at current productivity level. Result shows that high photosynthetic potential productivity area and high light and temperature potential productivity area are mainly situated in the north,while high climatic potential area and high land potential productivity area are mainly concentrated in the south. From solar radiation,moisture and landform,the attenuation amplitude of land potential productivity in northern counties ( districts) is greater than that in southern counties ( districts) . In the whole city,the population carrying capacity of 9 counties reaches well-off living level,and 1 district still does not reach the level of adequate food and clothing. These results can provide reference for land resource use,agricultural production distribution and population growth control.

  15. Analysis on economic carrying capacity index of pig breeding in China

    Science.gov (United States)

    Leng, Bi-Bin; Liu, Jia-Ling; Xu, Yue-Feng

    2017-08-01

    In this paper, factor analysis method was employed to analyze and calculate the Gross Domestic Product (GDP) per capita in the last decade, the proportion of research and experiment development (R&D) expenditure equivalent to GDP, urban and rural residents’ pork consumption and explored the scale of Chinese pig breeding on economic carrying capacity index. The result showed that the growth of GDP had led to better techniques and higher field investment, and stronger support like science and technology from the government provided good conditions for large scale of pig breeding. Besides, the substantial increase of pork consumption between rural and urban residents has contributed to the pig breeding in large scale. As a result, the economic carrying capacity index in Chinese pig farming is on the rise.

  16. Integrating resource, social, and managerial indicators of quality into carrying capacity decision-making

    Science.gov (United States)

    Newman, P.; Marion, J.; Cahill, K.

    2001-01-01

    In park and wilderness management, integrating social and resource indicators is essential to meet park mandates that require the protection of both experiential and resource conditions. This paper will address the challenges we face in integrating social and resource data and outline a study in progress in Yosemite National Park. This study will develop and apply a management model that integrates resource, social and managerial indicators of quality into carrying capacity decisionmaking.

  17. Experimental Determination of Load Carrying Capacity of Point Contacts at Zero Entrainment Velocity

    Science.gov (United States)

    Shogrin, Bradley A.; Jones, William R., Jr.; Kingsbury, Edward P.; Prahl, Joseph M.

    1999-01-01

    A capacitance technique was used to monitor the film thickness separating two steel balls of a unique tribometer while subjecting the ball-ball contact to highly stressed, zero entrainment velocity (ZEV) conditions. All tests were performed under a N2 purge (R.H. carrying capacity at these zero entrainment velocity conditions, relevant to the ball-ball contact application in retainerless ball bearings.

  18. Thermal carrying capacity for a thermally-sensitive species at the warmest edge of its range.

    Directory of Open Access Journals (Sweden)

    Daniel Ayllón

    Full Text Available Anthropogenic environmental change is causing unprecedented rates of population extirpation and altering the setting of range limits for many species. Significant population declines may occur however before any reduction in range is observed. Determining and modelling the factors driving population size and trends is consequently critical to predict trajectories of change and future extinction risk. We tracked during 12 years 51 populations of a cold-water fish species (brown trout Salmo trutta living along a temperature gradient at the warmest thermal edge of its range. We developed a carrying capacity model in which maximum population size is limited by physical habitat conditions and regulated through territoriality. We first tested whether population numbers were driven by carrying capacity dynamics and then targeted on establishing (1 the temperature thresholds beyond which population numbers switch from being physical habitat- to temperature-limited; and (2 the rate at which carrying capacity declines with temperature within limiting thermal ranges. Carrying capacity along with emergent density-dependent responses explained up to 76% of spatio-temporal density variability of juveniles and adults but only 50% of young-of-the-year's. By contrast, young-of-the-year trout were highly sensitive to thermal conditions, their performance declining with temperature at a higher rate than older life stages, and disruptions being triggered at lower temperature thresholds. Results suggest that limiting temperature effects were progressively stronger with increasing anthropogenic disturbance. There was however a critical threshold, matching the incipient thermal limit for survival, beyond which realized density was always below potential numbers irrespective of disturbance intensity. We additionally found a lower threshold, matching the thermal limit for feeding, beyond which even unaltered populations declined. We predict that most of our study

  19. Thermal carrying capacity for a thermally-sensitive species at the warmest edge of its range.

    Science.gov (United States)

    Ayllón, Daniel; Nicola, Graciela G; Elvira, Benigno; Parra, Irene; Almodóvar, Ana

    2013-01-01

    Anthropogenic environmental change is causing unprecedented rates of population extirpation and altering the setting of range limits for many species. Significant population declines may occur however before any reduction in range is observed. Determining and modelling the factors driving population size and trends is consequently critical to predict trajectories of change and future extinction risk. We tracked during 12 years 51 populations of a cold-water fish species (brown trout Salmo trutta) living along a temperature gradient at the warmest thermal edge of its range. We developed a carrying capacity model in which maximum population size is limited by physical habitat conditions and regulated through territoriality. We first tested whether population numbers were driven by carrying capacity dynamics and then targeted on establishing (1) the temperature thresholds beyond which population numbers switch from being physical habitat- to temperature-limited; and (2) the rate at which carrying capacity declines with temperature within limiting thermal ranges. Carrying capacity along with emergent density-dependent responses explained up to 76% of spatio-temporal density variability of juveniles and adults but only 50% of young-of-the-year's. By contrast, young-of-the-year trout were highly sensitive to thermal conditions, their performance declining with temperature at a higher rate than older life stages, and disruptions being triggered at lower temperature thresholds. Results suggest that limiting temperature effects were progressively stronger with increasing anthropogenic disturbance. There was however a critical threshold, matching the incipient thermal limit for survival, beyond which realized density was always below potential numbers irrespective of disturbance intensity. We additionally found a lower threshold, matching the thermal limit for feeding, beyond which even unaltered populations declined. We predict that most of our study populations may become

  20. Determination of foraging thresholds and effects of application on energetic carrying capacity for waterfowl.

    Science.gov (United States)

    Hagy, Heath M; Kaminski, Richard M

    2015-01-01

    Energetic carrying capacity of habitats for wildlife is a fundamental concept used to better understand population ecology and prioritize conservation efforts. However, carrying capacity can be difficult to estimate accurately and simplified models often depend on many assumptions and few estimated parameters. We demonstrate the complex nature of parameterizing energetic carrying capacity models and use an experimental approach to describe a necessary parameter, a foraging threshold (i.e., density of food at which animals no longer can efficiently forage and acquire energy), for a guild of migratory birds. We created foraging patches with different fixed prey densities and monitored the numerical and behavioral responses of waterfowl (Anatidae) and depletion of foods during winter. Dabbling ducks (Anatini) fed extensively in plots and all initial densities of supplemented seed were rapidly reduced to 10 kg/ha and other natural seeds and tubers combined to 170 kg/ha, despite different starting densities. However, ducks did not abandon or stop foraging in wetlands when seed reduction ceased approximately two weeks into the winter-long experiment nor did they consistently distribute according to ideal-free predictions during this period. Dabbling duck use of experimental plots was not related to initial seed density, and residual seed and tuber densities varied among plant taxa and wetlands but not plots. Herein, we reached several conclusions: 1) foraging effort and numerical responses of dabbling ducks in winter were likely influenced by factors other than total food densities (e.g., predation risk, opportunity costs, forager condition), 2) foraging thresholds may vary among foraging locations, and 3) the numerical response of dabbling ducks may be an inconsistent predictor of habitat quality relative to seed and tuber density. We describe implications on habitat conservation objectives of using different foraging thresholds in energetic carrying capacity models and

  1. Carrying capacity in arid rangelands during droughts: the role of temporal and spatial thresholds.

    Science.gov (United States)

    Accatino, F; Ward, D; Wiegand, K; De Michele, C

    2017-02-01

    Assessing the carrying capacity is of primary importance in arid rangelands. This becomes even more important during droughts, when rangelands exhibit non-equilibrium dynamics, and the dynamics of livestock conditions and forage resource are decoupled. Carrying capacity is usually conceived as an equilibrium concept, that is, the consumer density that can co-exist in long-term equilibrium with the resource. As one of the first, here we address the concept of carrying capacity in systems, where there is no feedback between consumer and resource in a limited period of time. To this end, we developed an individual-based model describing the basic characteristics of a rangeland during a drought. The model represents a rangeland composed by a single water point and forage distributed all around, with livestock units moving from water to forage and vice versa, for eating and drinking. For each livestock unit we implemented an energy balance and we accounted for the gut-filling effect (i.e. only a limited amount of forage can be ingested per unit time). Our results showed that there is a temporal threshold above which livestock begin to experience energy deficit and burn fat reserves. We demonstrated that such a temporal threshold increases with the number of animals and decreases with the rangeland conditions (amount of forage). The temporal threshold corresponded to the time livestock take to consume all the forage within a certain distance from water, so that the livestock can return to water for drinking without spending more energy than they gain within a day. In this study, we highlight the importance of a time threshold in the assessment of carrying capacity in non-equilibrium conditions. Considering this time threshold could explain contrasting observations about the influence of livestock number on livestock conditions. In case of private rangelands, the herd size should be chosen so that the spatial threshold equals (or exceeds) the length of the drought.

  2. Ecological carrying capacity assessment of diving site: A case study of Mabul Island, Malaysia.

    Science.gov (United States)

    Zhang, Li-Ye; Chung, Shan-Shan; Qiu, Jian-Wen

    2016-12-01

    Despite considered a non-consumptive use of the marine environment, diving-related activities can cause damages to coral reefs. It is imminent to assess the maximum numbers of divers that can be accommodated by a diving site before it is subject to irreversible deterioration. This study aimed to assess the ecological carrying capacity of a diving site in Mabul Island, Malaysia. Photo-quadrat line transect method was used in the benthic survey. The ecological carrying capacity was assessed based on the relationship between the number of divers and the proportion of diver damaged hard corals in Mabul Island. The results indicated that the proportion of diver damaged hard corals occurred exponentially with increasing use. The ecological carrying capacity of Mabul Island is 15,600-16,800 divers per diving site per year at current levels of diver education and training with a quarterly threshold of 3900-4200 per site. Our calculation shows that management intervention (e.g. limiting diving) is justified at 8-14% of hard coral damage. In addition, the use of coral reef dominated diving sites should be managed according to their sensitivity to diver damage and the depth of the reefs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. A Study on the Thermal Effect of the Current-Carrying Capacity of Embedded Underground Cable

    Directory of Open Access Journals (Sweden)

    LI Dewen

    2012-10-01

    Full Text Available The current paper aims to study embedded underground cable and the effect of temperature that surrounds it. Determining the carrying capacity of the cable is important to predict the temperature changesin the embedded pipe. Simulating the temperature field and the laying environment according to the IEC standard enables the calculation of the carrying capacity of the buried region. According to the theoryof heat transfer, the embedded pipe tube model temperature field should be coupled with a numerical model. The domain and boundary conditions of the temperature field should also be determined using the 8.7/15kV YJV 400 cable. In conducting numerical calculation and analysis using the temperature field model, the two-dimensional temperature distribution of the emission control area should be determined. The experimental results show that the simulation isconsistent with the IEC standard. Furthermore, in identifying the cable ampacity, the different seasons and different cable rows should be taken into account using the finite element method. Finally, theappropriate choice of root and circuit numbers of the cable will improve the cable’s the carrying capacity.

  4. On evolutionary stability of carrying capacity driven dispersal in competition with regularly diffusing populations.

    Science.gov (United States)

    Korobenko, L; Braverman, E

    2014-11-01

    Two competing populations in spatially heterogeneous but temporarily constant environment are investigated: one is subject to regular movements to lower density areas (random diffusion) while the dispersal of the other is in the direction of the highest per capita available resources (carrying capacity driven diffusion). The growth of both species is subject to the same general growth law which involves Gilpin-Ayala, Gompertz and some other equations as particular cases. The growth rate, carrying capacity and dispersal rate are the same for both population types, the only difference is the dispersal strategy. The main result of the paper is that the two species cannot coexist (unless the environment is spatially homogeneous), and the carrying capacity driven diffusion strategy is evolutionarily stable in the sense that the species adopting this strategy cannot be invaded by randomly diffusing population. Moreover, once the invasive species inhabits some open nonempty domain, it would spread over any available area bringing the native species diffusing randomly to extinction. One of the important technical results used in the proofs can be interpreted in the form that the limit solution of the equation with a regular diffusion leads to lower total population fitness than the ideal free distribution.

  5. Density and carrying capacity in the forgotten tigerland: tigers in understudied Nepalese Churia.

    Science.gov (United States)

    Thapa, Kanchan; Kelly, Marcella J

    2016-10-13

    While there are numerous wildlife ecology studies in lowland areas of Nepal, there are no in-depth studies of the hilly Churia habitat even though it comprises 7,642 km(2) of potential wildlife habitat across the Terai Arc. We investigated tiger, leopard, and prey densities across this understudied habitat. Our camera trapping survey covered 536 km(2) of Churia and surrounding areas within Chitwan National Park (CNP). We used 161 trapping locations and accumulated 2,097 trap nights in a 60-day survey period during the winter season of 2010-2011. Additionally, we walked 136 km over 81 different line transects using distance sampling to estimate prey density. We photographed 31 individual tigers, 28 individual leopards, and 25 other mammalian species. Spatial capture recapture methods resulted in lower density estimates for tigers ranging from 2.3-2.9 tigers per 100 km(2) , than for leopards, which ranged from 3.3-5.1 leopards per 100 km(2) . Additionally, leopard densities were higher in the core of the Churia compared to surrounding areas. We estimated 62.7 prey animals per 100 km(2) with forest ungulate prey (sambar, chital, barking deer, and wild pig) accounting for 47% of the total. Based on prey availability, Churia habitat within CNP could potentially support 5.86 tigers per 100 km(2) but our density estimates were lower, perhaps indicating the tiger population is below carrying capacity. Our results demonstrate that Churia habitat should not be ignored in conservation initiatives, but rather management efforts should focus on reducing human disturbance to support higher predator numbers. This article is protected by copyright. All rights reserved.

  6. The tourism carrying capacity of underwater trails in Isabel Island National Park, Mexico.

    Science.gov (United States)

    Ríos-Jara, Eduardo; Galván-Villa, Cristian Moisés; Rodríguez-Zaragoza, Fabián Alejandro; López-Uriarte, Ernesto; Muñoz-Fernández, Vicente Teófilo

    2013-08-01

    The popularity of ecotourism in the marine protected areas of Mexico has increased over the last 10 years; in particular there is a large development of a SCUBA diving industry in the Mexican Pacific including Isabel Island. Given the risks associated with human activity in the marine environments around this island, we propose two ecotourism management strategies: (1) the creation and use of underwater trails, and (2) the estimation of the specific tourism carrying capacity (TCC) for each trail. Six underwater trails were selected in sites that presented elements of biological, geological, and scenic interest, using information obtained during field observations. The methodology used to estimate the TCC was based upon the physical and biological conditions of each site, the infrastructure and equipment available, and the characteristics of the service providers and the administrators of the park. Correction factors of the TCC included elements of the quality of the visit and the threat and vulnerability of the marine environment of each trail (e.g., divers' expertise, size and distance between groups of divers, accessibility, wind, coral coverage). The TCC values ranged between 1,252 and 1,642 dives/year/trail, with a total of 8,597 dives/year for all six trails. Although these numbers are higher than the actual number of recreational visitors to the island (~1,000 dives per year), there is a need for adequate preventive management if the diving sites are to maintain their esthetic appeal and biological characteristics. Such management might be initially directed toward using only the sites and the TCC proposed here.

  7. The Tourism Carrying Capacity of Underwater Trails in Isabel Island National Park, Mexico

    Science.gov (United States)

    Ríos-Jara, Eduardo; Galván-Villa, Cristian Moisés; Rodríguez-Zaragoza, Fabián Alejandro; López-Uriarte, Ernesto; Muñoz-Fernández, Vicente Teófilo

    2013-08-01

    The popularity of ecotourism in the marine protected areas of Mexico has increased over the last 10 years; in particular there is a large development of a SCUBA diving industry in the Mexican Pacific including Isabel Island. Given the risks associated with human activity in the marine environments around this island, we propose two ecotourism management strategies: (1) the creation and use of underwater trails, and (2) the estimation of the specific tourism carrying capacity (TCC) for each trail. Six underwater trails were selected in sites that presented elements of biological, geological, and scenic interest, using information obtained during field observations. The methodology used to estimate the TCC was based upon the physical and biological conditions of each site, the infrastructure and equipment available, and the characteristics of the service providers and the administrators of the park. Correction factors of the TCC included elements of the quality of the visit and the threat and vulnerability of the marine environment of each trail (e.g., divers' expertise, size and distance between groups of divers, accessibility, wind, coral coverage). The TCC values ranged between 1,252 and 1,642 dives/year/trail, with a total of 8,597 dives/year for all six trails. Although these numbers are higher than the actual number of recreational visitors to the island (~1,000 dives per year), there is a need for adequate preventive management if the diving sites are to maintain their esthetic appeal and biological characteristics. Such management might be initially directed toward using only the sites and the TCC proposed here.

  8. Response of carrying capacity of piles induced by adjacent Metro tunneling

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-jie; DENG Fei-huang; WU Jia-jia; LIU Jian; WANG Fu-qiang

    2009-01-01

    Construction of tunnels in urban areas requires assessment of the impact of tunneling on the stability and integrity of existing pile foundations. We have focused our attention to the analysis of the carrying capacity of pile foundations provided by the impact of construction of urban tunnels on adjacent pile foundations, under the engineering background of the construction of the # 2 Line of the Guangzhou subway. It is carried out using a fast Lagrangian analysis of a continuum in a 3D numerical code, which is an elastoplastic three-dimensional finite difference model, to simulate the response of piles under the entire process of metro tun-neling (deactivation of soil element and activation of the lining). The adjacent stratum around the tunnel is classified into three re-gions: Zone Ⅰ(upper adjacent stratum of tunnel), Zone Ⅱ (45°-upper-lateral adjacent stratum of tunnel) and Zone Ⅲ (lateral adjacent stratum of tunnel). In each region one typical pile is chosen to be calculated and analyzed in detail. Numerical simulations are mainly conducted at three points of each pile shaft: the side-friction force of the pile, the tip resistance of the pile and the axial loading of the pile. A contrasting analysis has been conducted both in the response of typical piles in different regions and from computer calculated values with site monitoring values. The results of numerical simulations show that the impact on carrying ca-pacity of the piles lies mainly in the impact of construction of urban tunnels on the side-friction forces and the tip resistance of piles. The impact differs considerably among the different strata zones where the pile tips are located. The complicated rules of side-friction force and tip resistance of piles has resulted in complicated rules of pile axial loading thus, in the end, it impacts the carrying capacity of pile-foundations. It is necessary to take positive measures, such as stratum grouting stabilization or foundation underpinning, ete

  9. The Analysis and Calculation Method of Urban Rail Transit Carrying Capacity Based on Express-Slow Mode

    OpenAIRE

    Xiaobing Ding; Shengrun Zhang; Zhigang Liu; Hua Hu; Xingfang Xu; Weixiang Xu

    2016-01-01

    Urban railway transport that connects suburbs and city areas is characterized by uneven temporal and spatial distribution in terms of passenger flow and underutilized carrying capacity. This paper aims to develop methodologies to measure the carrying capacity of the urban railway by introducing a concept of the express-slow mode. We first explore factors influencing the carrying capacity under the express-slow mode and the interactive relationships among these factors. Then we establish seven...

  10. Carrying capacity for shorebirds during migratory seasons at the Jiuduansha Wetland, Yangtze River Estuary, China

    Institute of Scientific and Technical Information of China (English)

    Zhenming GE; Xiao ZHOU; Wenyu SHI; Tianhou WANG

    2008-01-01

    The carrying capacity of food resources for migrating shorebirds was estimated at a stopover site in the Yangtze River Estuary during the two migratory sea-sons (spring and autumn). From March to May and September to November 2005, the macrobenthos resources of the Jiuduansha Wetland were investigated, and most of the macrobenthos species in the newly-formed shoal were found to be appropriate food for shorebirds. Biomass measurements showed that the total food resource was about 4541.20 kg AFDW (Ash-Free Dry Weight) in spring and about 2279.64 kg AFDW in autumn. Calculations were also done in the available habi-tats (intertidal bare mudflat and Scirpus x mariqueter/ Scirpus triqueter zones) for the shorebirds. The food resources in the available areas were about 3429.03 kg AFDW in spring and about 1700.92 kg AFDW in autumn. Based on the classification (by lean weight, basic metabolic rate and body length) of the shorebird community, and using the energy depletion model, it was theorized that all of the food resources in the Jiuduansha Wetland could support about 3.5 million shorebirds during spring season and 1.75 million shorebirds during autumn season. The shorebird carrying capacities in terms of the available food were about 2.6 million and 1.3 million birds during the two respective migration seasons. Considering the effect of intake rate, the potential carrying capacity was about 0.13-0.26 million shorebirds in the study area. The main factor restricting use of the area by shorebirds was the scarcity of available habitats for roosting at high tide rather than availability of food supply. We recommend restoring some wading pools in the dense Phragmites australis and Spartina alterniflora zones for shorebirds to roost in, to improve shorebirds' utilization efficiency of the resources in the Jiuduansha Wetland.

  11. Rural Settlement Development and Environment Carrying Capacity Changes in Progo River Basin

    Directory of Open Access Journals (Sweden)

    Su Ritohardoyo

    2016-12-01

    Full Text Available Generally the broader rural settlement the heavier population pressure on agricultural land. It indicates that carrying capacity of the rural environment threatened lower. The spatial distribution of the threat in a river basin is quite important as one of the river basin management inputs. Therefore, this article aims at exposing result of research about influence rural population growth and rural settlement land changes to environment carrying capacity. This research was carried out in the rural area in Progo river basin consists 56 sub districts (34 sub districts part of Jawa Tengah Province, and 22 sub districts part of Yogyakarta Special Region. The whole sub districts are such as unit analysis, and research method is based on secondary data analysis. Several data consist Districts Region in Figure 1997 and 2003 (Temanggung, Magelang, Kulon Progo, Sleman and Bantul such as secondary data analysis. Data analysis employs of frequency and cross tabulation, statistics of regression and test. Result of the research shows that population growth of the rural areas in Progo river basin are about 0.72% annum; or the household growth about 3.15% annum as long as five years (1996-2003. Spatial distribution of the population growth in the upper part of the Progo river basin is higher than in the middle and lower part of the basin. The number proportion of farmer in every sub district area in this river basin have increased from 69.95% in 1997 to 70.81% in the year of 2003. It means that work opportunities broadening are still sluggish. However, the number proportion of farmers in the upper part of the Progo river basin is lower than in the middle and lower part of the basin. The rates of settlement land areas changes (0.32 ha/annum as long as five years (1997-2003 is not as fast as the rates of agricultural land areas changes (0.47 ha/annum. Spatial land settlement areas changes in the lower (6.1 ha/annum and middle parts (2.4 ha/annum faster than

  12. Optimization of industrial structure based on water environmental carrying capacity in Tieling City.

    Science.gov (United States)

    Yue, Qiang; Hou, Limin; Wang, Tong; Wang, Liusuo; Zhu, Yue; Wang, Xiu; Cheng, Xilei

    2015-01-01

    A system dynamics optimization model of the industrial structure of Tieling City based on water environmental carrying capacity has been established. This system is divided into the following subsystems: water resources, economics, population, contaminants, and agriculture and husbandry. Three schemes were designed to simulate the model from 2011 to 2020, and these schemes were compared to obtain an optimal social and economic development model in Tieling City. Policy recommendations on industrial structure optimization based on the optimal solution provide scientific decision-making advice to develop a strong and sustainable economy in Tieling.

  13. Impact of Flexibility Options on Grid Economic Carrying Capacity of Solar and Wind: Three Case Studies

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Novacheck, Joshua [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Lab. (NREL), Golden, CO (United States); O' Connell, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-12-01

    In this study, we attempt to quantify the benefits of various options of grid flexibility by measuring their impact on two measures: economic carrying capacity and system costs. Flexibility can increase ECC and reduce overall system costs. In some cases, options that provide a limited increase in ECC can provide significant operational savings, thus demonstrating the need to evaluate flexibility options using multiple metrics. The value of flexibility options varies regionally due to different generation mixes and types of renewables. The more rapid decline in PV value compared to wind makes PV more dependent on adding flexibility options, including transmission and energy storage.

  14. The effect of manufacturing tolerances on the load carrying capacity of large diameter bearings

    Indian Academy of Sciences (India)

    Starvin M S; Manisekar K

    2015-09-01

    This paper deals with simplified 3D finite element (FE) analysis on the effect of manufacturing tolerances on the load carrying capacity of large diameter bearings based on Hertz theory. The nonlinear connector elements are used to model the rolling elements. This model enables us to evaluate the contact load on the rolling elements with relatively reduced calculation time. FE study has been carried out by allocating tolerance on balls and raceways using Monte Carlo simulation technique. The variation in dimension on balls is taken as per IS 2898-1976. A coding has been developed and employed for Monte Carlo simulation. Using the results of Monte Carlo simulation, tolerance has been assigned to the elements of large diameter bearing. From the results of finite element analysis, it is identified that analysis of large diameter bearing with tolerance on ball and raceway will lead to safe design.

  15. [Evaluation of land resources carrying capacity of development zone based on planning environment impact assessment].

    Science.gov (United States)

    Fu, Shi-Feng; Zhang, Ping; Jiang, Jin-Long

    2012-02-01

    Assessment of land resources carrying capacity is the key point of planning environment impact assessment and the main foundation to determine whether the planning could be implemented or not. With the help of the space analysis function of Geographic Information System, and selecting altitude, slope, land use type, distance from resident land, distance from main traffic roads, and distance from environmentally sensitive area as the sensitive factors, a comprehensive assessment on the ecological sensitivity and its spatial distribution in Zhangzhou Merchants Economic and Technological Development Zone, Fujian Province of East China was conducted, and the assessment results were combined with the planning land layout diagram for the ecological suitability analysis. In the Development Zone, 84.0% of resident land, 93.1% of industrial land, 86.0% of traffic land, and 76. 0% of other constructive lands in planning were located in insensitive and gently sensitive areas, and thus, the implement of the land use planning generally had little impact on the ecological environment, and the land resources in the planning area was able to meet the land use demand. The assessment of the population carrying capacity with ecological land as the limiting factor indicated that in considering the highly sensitive area and 60% of the moderately sensitive area as ecological land, the population within the Zone in the planning could reach 240000, and the available land area per capita could be 134.0 m2. Such a planned population scale is appropriate, according to the related standards of constructive land.

  16. Studies on water resources carrying capacity in Tuhai river basin based on ecological footprint

    Science.gov (United States)

    Wang, Chengshuai; Xu, Lirong; Fu, Xin

    2017-05-01

    In this paper, the method of the water ecological footprint (WEF) was used to evaluate water resources carrying capacity and water resources sustainability of Tuhai River Basin in Shandong Province. The results show that: (1) The WEF had a downward trend in overall volatility in Tuhai River Basin from 2003 to 2011. Agricultural water occupies high proportion, which was a major contributor to the WEF, and about 86.9% of agricultural WEF was used for farmland irrigation; (2) The water resources carrying capacity had a downward trend in general, which was mostly affected by some natural factors in this basin such as hydrology and meteorology in Tuhai River Basin; (3) Based on analysis of water resources ecological deficit, it can be concluded that the water resources utilization mode was in an unhealthy pattern and it was necessary to improve the utilization efficiency of water resources in Tuhai River Basin; (4) In view of water resources utilization problems in the studied area, well irrigation should be greatly developed at the head of Yellow River Irrigation Area(YRIA), however, water from Yellow River should be utilized for irrigation as much as possible, combined with agricultural water-saving measures and controlled exploiting groundwater at the tail of YRIA. Therefore, the combined usage of surface water and ground water of YRIA is an important way to realize agricultural water saving and sustainable utilization of water resources in Tuhai River Basin.

  17. Study on the carry capacity of edible jellyfish fishery in Liaodong Bay

    Science.gov (United States)

    You, Kui; Bian, Yongning; Ma, Caihua; Chi, Xupeng; Liu, Zhiqiang; Zhang, Yuyu

    2016-06-01

    Jellyfish fishing is a special type of fishery that mainly exists in some countries of East and Southeast Asia. China has the largest jellyfish fishery yield in the world with an annual harvest of around 300 thousand tons. Liaodong Bay is the most important jellyfish fishery ground in China. However, due to the high benefits of jellyfish fishery, which leads to illegal and out-of-season jellyfish fishing occurring each year in Liaodong Bay. Illegal jellyfish fishery in Liaodong Bay is a typical example of the tragedy of the commons. The key problem is that fishermen seek to an illegally initiate jellyfish fishing as early as possible. In this paper, basing on the data of edible jellyfish's biology and ecology, we mainly analyzed the history of jellyfish fishery in China, especially in Liaodong bay, and then we calculated the carry capacity of edible jellyfish in Liaodong Bay which is about 300 thousand tons one year. This number is equal to the recent annual yield of edible jellyfish in China. Furthermore, basing on the carry capacity and reasonable quotas price analysis, we set up a Jellyfish fishing quotas and deficit quotas buyback system which could be a suitable and effective solution for jellyfish fishery management and development in Liaodong Bay at the underlying roots. Although China is the first country with edible jellyfish aquaculture, the annual yield of jellyfish aquaculture is only one fifth of jellyfish fishing. So, there is a very bright developing prospect about edible jellyfish aquaculture in China.

  18. Hyperspectral Biofilm Classification Analysis for Carrying Capacity of Migratory Birds in the South Bay Salt Ponds

    Science.gov (United States)

    Ketron, T.; Hsu, W.; Kuss, A. M.; Nguyen, A.; Remar, A. C.; Newcomer, M. E.; Fleming, E.; Bebout, L.; Bebout, B.; Detweiler, A. M.; Skiles, J. W.

    2011-12-01

    Tidal marshes are highly productive ecosystems that support migratory birds as roosting and over-wintering habitats on the Pacific Flyway. Microphytobenthos, or more commonly 'biofilms' contribute significantly to the primary productivity of wetland ecosystems, and provide a substantial food source for macroinvertebrates and avian communities. In this study, biofilms were characterized based on taxonomic classification, density differences, and spectral signatures. These techniques were then applied to remotely sensed images to map biofilm densities and distributions in the South Bay Salt Ponds and predict the carrying capacity of these newly restored ponds for migratory birds. The GER-1500 spectroradiometer was used to obtain in situ spectral signatures for each density-class of biofilm. The spectral variation and taxonomic classification between high, medium, and low density biofilm cover types was mapped using in-situ spectral measurements and classification of EO-1 Hyperion and Landsat TM 5 images. Biofilm samples were also collected in the field to perform laboratory analyses including chlorophyll-a, taxonomic classification, and energy content. Comparison of the spectral signatures between the three density groups shows distinct variations useful for classification. Also, analysis of chlorophyll-a concentrations show statistically significant differences between each density group, using the Tukey-Kramer test at an alpha level of 0.05. The potential carrying capacity in South Bay Salt Ponds is estimated to be 250,000 birds.

  19. Hyperspectral Biofilm Classification Analysis for Carrying Capacity of Migratory Birds in the South Bay Salt Ponds

    Science.gov (United States)

    Hsu, Wei-Chen; Kuss, Amber Jean; Ketron, Tyler; Nguyen, Andrew; Remar, Alex Covello; Newcomer, Michelle; Fleming, Erich; Debout, Leslie; Debout, Brad; Detweiler, Angela; hide

    2011-01-01

    Tidal marshes are highly productive ecosystems that support migratory birds as roosting and over-wintering habitats on the Pacific Flyway. Microphytobenthos, or more commonly 'biofilms' contribute significantly to the primary productivity of wetland ecosystems, and provide a substantial food source for macroinvertebrates and avian communities. In this study, biofilms were characterized based on taxonomic classification, density differences, and spectral signatures. These techniques were then applied to remotely sensed images to map biofilm densities and distributions in the South Bay Salt Ponds and predict the carrying capacity of these newly restored ponds for migratory birds. The GER-1500 spectroradiometer was used to obtain in situ spectral signatures for each density-class of biofilm. The spectral variation and taxonomic classification between high, medium, and low density biofilm cover types was mapped using in-situ spectral measurements and classification of EO-1 Hyperion and Landsat TM 5 images. Biofilm samples were also collected in the field to perform laboratory analyses including chlorophyll-a, taxonomic classification, and energy content. Comparison of the spectral signatures between the three density groups shows distinct variations useful for classification. Also, analysis of chlorophyll-a concentrations show statistically significant differences between each density group, using the Tukey-Kramer test at an alpha level of 0.05. The potential carrying capacity in South Bay Salt Ponds is estimated to be 250,000 birds.

  20. Soil water carrying capacity of vegetation in the northeast of Ulan Buh Desert, China

    Institute of Scientific and Technical Information of China (English)

    Youliang TIAN; Yanhong HE; Liansheng GUO

    2009-01-01

    The dynamic change of soil water as a function of leaf area index and the soil water deficit value, prerequisites for assuring the survival of plants, were simulated. We established a dynamic soil water model based on a theory of water balance, the characteristics of the environment, and the physiological ecology of the plants in the Ulan Buh Desert, northwestern China. We estimated the soil water carrying capacity of the vegetation in our study area of the desert. The results showed that the proportion of soil evaporation in the total amount of precipitation was greater than 60% in the wandering and semifixed sands and 44.8% in the fixed sand. When the leaf area index was less than 1.7 m2/m2, the soil water deficit was maintained at a low level, but when the leaf area index continued to increase, the soil water deficit increased rapidly as well. In consequence, we come to the conclusion that the leaf area index of the soil water carrying capacity of the vegetation is 1.7 m2/m2 in our study area.

  1. A method for prediction of extent of microbial pollution of seawater and carrying capacity of beaches

    Science.gov (United States)

    Kocasoy, Günay

    1989-07-01

    The increase in the number of tourists visiting a coast is desired by most of the countries for economic reasons. However, this increase in tourism may cause pollution of the sea. This can be only avoided by proper planning and by predicting the “carrying capacity” of the coast in terms of sea pollution. This is especially important for developing countries where part of the wastewater is discharged without any treatment into the sea. In the present study the beaches were classified according to their use — and consequently the amount of waste discharged into the sea — into four groups: (1) coasts that are used only for swimming and recreational purposes; (2) coasts used simultaneously for dwelling, swimming, and recreational purposes; (3) coasts along which only dwellings exist; and (4) natural and man-made harbors, i.e., coasts used as shelters. During the survey,40,320 observations were made between December 1985 and February 1988 to determine the effect of the number of tourists on seawater quality. The results obtained were analyzed by a multilinear regression program to obtain an empirical equation giving the extent of the sea pollution in terms of coliform concentration as a function of population density and some other environmental factors. The equations derived in this study enable the determination of the carrying capacity of a beach in terms of pollution as well as the expected degree of pollution corresponding to a given population density. Furthermore, it allows the prediction of the extra carrying capacity that can be obtained by improving the waste-disposal conditions.

  2. Dynamic Response of RPC-Filled Steel Tubular Columns with High Load Carrying Capacity Under Axial Impact Loading

    Institute of Scientific and Technical Information of China (English)

    TIAN Zhimin; WU Ping'an; JIA Jianwei

    2008-01-01

    Experimental investigation into impact-resistant behavior of reactive powder concrete (RPC)-filled steel tubular columns was conducted, and dynamic response of the columns under axial impact loading was studied by means of numerical simulation method.Increase coefficient of load carrying capacity and ratio of load carrying capacity between steel tube and RPC core of columns were obtained.

  3. An integrated approach for assessing aquatic ecological carrying capacity: a case study of Wujin District in the Tai Lake Basin, China.

    Science.gov (United States)

    Zeng, Chen; Liu, Yaolin; Liu, Yanfang; Hu, Jiameng; Bai, Xiaogang; Yang, Xiaoyu

    2011-01-01

    Aquatic ecological carrying capacity is an effective method for analyzing sustainable development in regional water management. In this paper, an integrated approach is employed for assessing the aquatic ecological carrying capacity of Wujin District in the Tai Lake Basin, China. An indicator system is established considering social and economic development as well as ecological resilience perspectives. While calculating the ecological index, the normalized difference vegetation index (NDVI) is extracted from Moderate Resolution Imaging Spectroradiometer (MODIS) time-series images, followed by spatial and temporal analysis of vegetation cover. Finally, multi-index assessment of aquatic ecological carrying capacity is carried out for the period 2000 to 2008, including both static and dynamic variables. The results reveal that aquatic ecological carrying capacity presents a slight upward trend in the past decade and the intensity of human activities still exceeded the aquatic ecological carrying capacity in 2008. In terms of human activities, population has decreased, GDP has quadrupled, and fertilizer application and industrial wastewater discharge have declined greatly in the past decade. The indicators representing aquatic ecosystem conditions have the lowest scores, which are primarily attributed to the water eutrophication problem. Yet the terrestrial ecosystem is assessed to be in better condition since topographic backgrounds and landscape diversity are at higher levels. Based on the work carried out, it is suggested that pollutant emission be controlled to improve water quality and agricultural development around Ge Lake (the largest lake in Wujin District) be reduced.

  4. What is the carrying capacity for fish in the ocean? A meta analysis of population dynamics of North Atlantic cod

    DEFF Research Database (Denmark)

    Myers, R.A.; MacKenzie, Brian; Bowen, K.G.;

    2001-01-01

    model 21 Atlanic cod (Gadus morhua) stocks in the North Atlantic assuming that the maximum reproductive rate and the carrying capacity per unit area are random variables. This method uses a nonlinear mixed model and is a natural approach to investigate how carrying capacity varies among populations. We...... used empirical Bayes techniques to estimate the maximum reproductive rate and carrying capacity of each stock. In all cases, the empirical Bayes estimates were biologically reasonable, whereas a stock by stock analysis occasionally yielded nonsensical parameter estimates (e.g., infinite values). Our...... analysis showed that the carrying capacity per unit area varied by more than 20-fold among populations and that much of this variation was related to temperature. That is, the carrying capacity per square kilometre declines as temperature increases....

  5. Seasonal dynamics in wheel load-carrying capacity of a loam soil in the Swiss Plateau

    DEFF Research Database (Denmark)

    Gut, S.; Chervet, A.; Stettler, Matthias

    2015-01-01

    ) is defined as the maximum wheel load for a specific tyre and inflation pressure that does not result in soil stress in excess of soil strength. The soil strength and hence WLCC is strongly influenced by soil matric potential (h). The aim of this study was to estimate the seasonal dynamics in WLCC based...... on in situ measurements of h, measurements of precompression stress at various h and simulations of soil stress. In this work, we concentrated on prevention of subsoil compaction. Calculations were made for different tyres (standard and low-pressure top tyres) and for soil under different tillage...... and cropping systems (mouldboard ploughing, direct drilling, permanent grassland), and the computed WLCC was compared with real wheel loads to obtain the number of trafficable days (NTD) for various agricultural machines. Wheel load-carrying capacity was higher for the top than the standard tyres...

  6. NEW APPROACHES FOR COMPUTING DYNAMIC LOAD-CARRYING CAPACITY OF MULTIPLE COOPERATING ROBOTIC MANIPULATORS

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    A novel unified method for computing the dynamic load-carrying capacity(DLCC) of multiple cooperating robotic manipulators is developed.In this method,the kinematic constraints and the governing dynamic equations of the multiple robot system are formulated in the joint space by using the method of transference of dependence from one set of generalized coordinates to another,and the virtual work principle,which includes the readily available dynamics and joint torques of individual manipulators,and the dynamic of payload.Based on this dynamic model,the upper limit of the DLCC at any points on a given trajectory is obtained by solving a small-size linear programming problem.This method is conceptually straightforward,and it is applicable also to the cases of multi-fingered robot hands and multi-legged walking machines.

  7. Ecological Carrying Capacity of Tibet China--Variety of Ecological Footprints from 1978 to 2002

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-bao; GAO Ji-xi; Lori Anna Conzo; GAO Ming-gang; HE Ping

    2005-01-01

    Ecological footprint's theory and method are used to calculate and analysis the ecological carrying capacity in Tibet. The results indicate: Tibet ecological footprint (2.1 hm2) keeps higher than countrywide average level (1.5 hm2), and lower than global average level (2.4 hm2); the result show that Tibet pasture ecological footprint is the most different with other area, and woodland is the second; Tibet ecological footprint grows from 1.25 hm2 in 1978 to 2.09 hm2 in 2002, which states that life level is improving continuously; GDP (per RMB 104 Yuan) ecological footprint reduces from 61.9 hm2 in 1978 to 4.54 hm2 in 2002, which states resources utilized ratio is increasing continuously.

  8. Load carrying capacity of RCC beams by replacing steel reinforcement bars with shape memory alloy bars

    Science.gov (United States)

    Bajoria, Kamal M.; Kaduskar, Shreya S.

    2016-04-01

    In this paper the structural behavior of reinforced concrete (RC) beams with smart rebars under two point loading system has been numerically studied, using Finite Element Method. The material used in this study is Super-elastic Shape Memory Alloys (SE SMAs) which contains nickel and titanium. In this study, different quantities of steel and SMA rebars have been used for reinforcement and the behavior of these models under two point bending loading system is studied. A comparison of load carrying capacity for the model between steel reinforced concrete beam and the beam reinforced with S.M.A and steel are performed. The results show that RC beams reinforced with combination of shape memory alloy and steel show better performance.

  9. System dynamics model of Suzhou water resources carrying capacity and its application

    Directory of Open Access Journals (Sweden)

    Li CHENG

    2010-06-01

    Full Text Available A model of Suzhou water resources carrying capacity (WRCC was set up using the method of system dynamics (SD. In the model, three different water resources utilization programs were adopted: (1 continuity of existing water utilization, (2 water conservation/saving, and (3 water exploitation. The dynamic variation of the Suzhou WRCC was simulated with the supply-decided principle for the time period of 2001 to 2030, and the results were characterized based on socio-economic factors. The corresponding Suzhou WRCC values for several target years were calculated by the model. Based on these results, proper ways to improve the Suzhou WRCC are proposed. The model also produced an optimized plan, which can provide a scientific basis for the sustainable utilization of Suzhou water resources and for the coordinated development of the society, economy, and water resources.

  10. Meta-analysis of carrying capacity and abundance-area relationships in marine fish species

    DEFF Research Database (Denmark)

    Mantzouni, Irene

    fish produced by spawners in a given year which subsequently grow and survive to become vulnerable to fishing gear) have reacted to temperature fluctuations, and in particular to extremes of temperature, throughout the north Atlantic. Meta-analytical methods based on effect sizes were employed......Knowledge on the carrying capacity and the abundance-area relationships of fish is critical to evaluate the impacts of exploitation and climate on the sustainability and also the recovery potential of the populations. Of particular interest is climate change, inducing major consequences...... for population dynamics and life histories of marine biota as it progresses in the 21st century. In the present PhD project, a variety of meta-analytic methods was employed to statistically combine data across the north Atlantic distributions of 3 commercially and ecologically important species; cod (Gadus...

  11. System dynamics model of Suzhou water resources carrying capacity and its application

    Institute of Scientific and Technical Information of China (English)

    Li CHENG

    2010-01-01

    A model of Suzhou water resources carrying capacity (WRCC) was set up using the method of system dynamics (SD).In the model, three different water resources utilization programs were adopted: (1) continuity of existing water utilization, (2) water conservation/saving, and (3) water exploitation.The dynamic variation of the Suzhou WRCC was simulated with the supply-decided principle for the time period of 2001 to 2030, and the results were characterized based on socio-economic factors.The corresponding Suzhou WRCC values for several target years were calculated by the model.Based on these results, proper ways to improve the Suzhou WRCC are proposed.The model also produced an optimized plan, which can provide a scientific basis for the sustainable utilization of Suzhou water resources and for the coordinated development of the society, economy, and water resources.

  12. Adhesive-bonded double-lap joints. [analytical solutions for static load carrying capacity

    Science.gov (United States)

    Hart-Smith, L. J.

    1973-01-01

    Explicit analytical solutions are derived for the static load carrying capacity of double-lap adhesive-bonded joints. The analyses extend the elastic solution Volkersen and cover adhesive plasticity, adherend stiffness imbalance and thermal mismatch between the adherends. Both elastic-plastic and bi-elastic adhesive representations lead to the explicit result that the influence of the adhesive on the maximum potential bond strength is defined uniquely by the strain energy in shear per unit area of bond. Failures induced by peel stresses at the ends of the joint are examined. This failure mode is particularly important for composite adherends. The explicit solutions are sufficiently simple to be used for design purposes

  13. Visitor perceptions and the shifting social carrying capacity of South Sinai's coral reefs.

    Science.gov (United States)

    Leujak, Wera; Ormond, Rupert F G

    2007-04-01

    To investigate how the perceptions and behaviour of visitors to coral reefs are influenced by their prior experience and knowledge of marine life, a questionnaire-based study was undertaken at sites in the Ras Mohammed National Park and at Sharm El Sheikh, South Sinai, Egypt. It was evident that over the 10-20 years during which these reefs have deteriorated (mainly due to reef-flat trampling), there have been interrelated shifts in the nature of visitors making use of them. First, there has been a shift from experienced divers and snorkellers to inexperienced snorkellers and non-snorkellers with a poorer knowledge of reef biology. Second, there has been a shift in the predominant nationalities of visitors, from German and British, through Italian, to Russian. More recent user groups both stated and showed that they had less experience of snorkelling; they also showed less knowledge of marine life and less interest in learning about it. Visitor perceptions of both the state of the marine life on the reefs and the acceptability of current visitor numbers also varied between groups. More recent visitor groups and visitors with less knowledge were more satisfied with reef health. In general, however, visitor perceptions of reef health did not correlate well with actual reef conditions, probably because more experienced visitors preferred less impacted sites with which they were nevertheless less satisfied than inexperienced visitors at heavily impacted sites. More recent visitor groups were also less bothered by crowding on the shore or in the water. Consequently, the apparent "social carrying capacity" of sites seems to be increasing to a level well above the likely "ecological carrying capacity".

  14. Relationships between nutritional condition of adult females and relative carrying capacity for rocky mountain Elk

    Science.gov (United States)

    Piasecke, J.R.; Bender, L.C.

    2009-01-01

    Lactation can have significant costs to individual and population-level productivity because of the high energetic demands it places on dams. Because the difference in condition between lactating and dry Rocky Mountain elk (Cervus elaphus nelsoni) cows tends to disappear as nutritional quality rises, the magnitude of that difference could be used to relate condition to habitat quality or the capability of habitats to support elk. We therefore compared nutritional condition of ???2.5-yr-old lactating and dry cows from six free-ranging RockyMountain elk populations throughout the United States.Our goal was to quantify differential accrual of body fat (BF) reserves to determine whether the condition of dry and lactating cows could be used to define relevant management thresholds of habitat quality (i.e., relative carrying capacity) and consequently potential performance of elk populations. Levels of BF that lactating cows were able to accrue in autumn and the proportional difference in BF between dry and lactating cows in autumn were related (F 1-2,10???16.2, Pnutritionally stressed condition, which may be limiting population performance. Using the logistic model to predict relative proximity to ecological carrying capacity (ECC), our population-years ranged from3-97%ofECCand proportion of the population lactating (an index of calf survival) was negatively related to proportion of ECC. Results indicate that the proportional difference in accrual of BF between lactating and dry cows can provide a sensitive index to where elk populations reside relative to the quality of their range.

  15. Effects of wetland management on carrying capacity of diving ducks and shorebirds in a coastal estuary

    Science.gov (United States)

    Brand, L. Arriana; Takekawa, John Y.; Shinn, Joel; Graham, Tanya; Buffington, Kevin; Gustafson, K. Benjamin; Smith, Lacy M.; Spring, Sarah E.; Miles, A. Keith

    2014-01-01

    With global loss of natural wetlands, managed wetlands increasingly support energy requirements for wintering shorebirds and waterfowl. Despite numerous studies of avian bioenergetics in freshwater systems, less is known of the energetic capacity of estuarine systems. In San Francisco Bay, managed saline ponds converted from former commercial salt evaporation ponds form part of the largest wetland restoration project on the Pacific coast of North America. A daily-ration model was applied to assess carrying capacity for diving ducks and shorebirds during four winter seasons (2007–2010) in seasonal and circulation ponds, each in two salinity classes. Diving ducks comprised an estimated 35,450 ± 1,559 (x ± SE) in average years and 45,458 ± 1,653 in peak years with > 95% in circulation ponds. Shorebirds comprised 64,253 ± 14,838 (x ± SE) in average years and 108,171 ± 4,854 in peak years with > 64% in seasonal ponds. Macroinvertebrate energy density was highest in mesohaline (5–30 ppt) circulation ponds and lowest in seasonal ponds for both guilds. Energy requirements for diving ducks in mesohaline followed by low-hyperhaline (30–80 ppt) circulation ponds were mostly met by available prey energy. Available energy for shorebirds was substantially less than they required in seasonal ponds but exceeded their needs in mesohaline circulation ponds. Mesohaline circulation ponds supported 9,443 ± 1,649 (x ± SE) shorebird use-days·ha-1 of accessible habitat and 2,297 ± 402 diving duck use-days·ha-1 of accessible habitat, twice the capacity of low-hyperhaline circulation ponds and greater than five times that of seasonal ponds for both guilds. Our results indicated that reducing salinity to mesohaline levels and altering water depth to increase accessibility substantially increased energy available for these species in estuarine managed ponds.

  16. STUDY OF CARRYING CAPACITY OF A CORRUGATED METAL CONSTRUCTION BY CRITERION OF YIELD HINGE DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Y. Y. Luchko

    2015-10-01

    Full Text Available Purpose. This research is aimed to: 1 calculation of equivalent forces caused by rolling stock in winter and summer seasons at different parameters of the irregularities of railway track; 2 research of bearing capacity of corrugated metal constructions (CMC in terms of development of plastic hinge in the top of the metal pipe due to irreversible residual deformation of the vertical and horizontal diameters of the pipe. Methodology. The calculation of equivalent forces is carried out according to the method of calculating the railway track on strength and stability. Further a mathematical algorithm was developed in the software environment of Mathcad 14, with which the calculations were made about the formation of a plastic hinge at the top of the pipe for different values of the irregularities of the railway track and the degree of compaction of soil backfill. In these studies, the calculations were carried out at the design value of the compaction degree of soil backfill and magnitude of dynamic loading on railway rolling stock. Findings. Analysis of multivariate calculations of testing the condition of occurrence of plastic hinge at the top of the pipe arch has revealed that the first plastic hinge, which occurs in the set of CMC is revealed only when there is a simultaneous unfavorable influence of two factors (causes. These are the factors: the assumption of the development of the track irregularities out of the allowable values without the implementation of measures to eliminate or limit the speed of trains (the first cause; reduction of compaction of soil backfill below the 90 % (the second cause. In case of absence of one of the causes the origin of the plastic hinge will not happen. Originality. It was the first time, when the bearing capacity of corrugated metal construction with large diameter (more than 6 m with account of factors complex: the degree of compaction of soil backfill, the magnitude of the dynamic loads from rolling stock

  17. A review and synthesis of recreation ecology research supporting carrying capacity and visitor use management decisionmaking

    Science.gov (United States)

    Marion, Jeff

    2016-01-01

    Resource and experiential impacts associated with visitation to wilderness and other similar backcountry settings have long been addressed by land managers under the context of “carrying capacity” decisionmaking. Determining a maximum level of allowable use, below which high-quality resource and experiential conditions would be sustained, was an early focus in the 1960s and 1970s. However, decades of recreation ecology research have shown that the severity and areal extent of visitor impact problems are influenced by an interrelated array of use-related, environmental, and managerial factors. This complexity, with similar findings from social science research, prompted scientists and managers to develop more comprehensive carrying capacity frameworks, including a new Visitor Use Management framework. These frameworks rely on a diverse array of management strategies and actions, often termed a “management toolbox,” for resolving visitor impact problems. This article reviews the most recent and relevant recreation ecology studies that have been applied in wildland settings to avoid or minimize resource impacts. The key findings and their management implications are highlighted to support the professional management of common trail, recreation site, and wildlife impact problems. These studies illustrate the need to select from a more diverse array of impact management strategies and actions based on an evaluation of problems to identify the most influential factors that can be manipulated.

  18. The Analysis and Calculation Method of Urban Rail Transit Carrying Capacity Based on Express-Slow Mode

    Directory of Open Access Journals (Sweden)

    Xiaobing Ding

    2016-01-01

    Full Text Available Urban railway transport that connects suburbs and city areas is characterized by uneven temporal and spatial distribution in terms of passenger flow and underutilized carrying capacity. This paper aims to develop methodologies to measure the carrying capacity of the urban railway by introducing a concept of the express-slow mode. We first explore factors influencing the carrying capacity under the express-slow mode and the interactive relationships among these factors. Then we establish seven different scenarios to measure the carrying capacity by considering the ratio of the number of the express trains and the slow trains, the station where overtaking takes place, and the number of overtaking maneuvers. Taking Shanghai Metro Line 16 as an empirical study, the proposed methods to measure the carrying capacity under different express-slow mode are proved to be valid. This paper contributes to the literature by remodifying the traditional methods to measure the carrying capacity when different express-slow modes are applied to improve the carrying capacity of the suburban railway.

  19. Model for determining the load or carrying capacity of rivers and riverbanks for recreational use

    Directory of Open Access Journals (Sweden)

    Otero, I.

    2015-12-01

    Full Text Available The aim of this article is to determine the load or functional carrying capacity for the assimilation and recovery of rivers and riverbanks by compiling information on the environment, and to assess the potential for recreation from the environmental and scenic point of view. We set out to find the most significant basis for analysing the pressures limiting carrying capacity and constraining the demand for recreational use. This methodology will help planners and legislators in their decision-making. We also propose a methodology for assessing the recreational use of riverbanks, tested in a number of sites in the Madrid Region, in terms of the satisfaction the activity produces in the users, and the load or carrying capacity of the surrounding environment. A pilot site assessment is presented as a validation of the proposed methodology.El objetivo de este artículo es, determinar la capacidad de carga o acogida funcional, de asimilación y de recuperación de los márgenes y los cursos fluviales mediante la recopilación de información del medio; el potencial recreativo se evalúa además desde un doble punto de vista: ecológico y paisajístico. La forma en que se enfoca el problema y se presenta la metodología y los resultados puede resultar de gran utilidad para planificadores y legisladores. La metodología propuesta para valorar el uso recreativo de los márgenes fluviales, se aplica a una serie de parcelas en la Comunidad de Madrid, teniendo en cuenta la satisfacción que la actividad produce en los usuarios, y la capacidad de carga o acogida del entorno en el que se desarrollan. Como resultado, se presenta la valoración de parcelas piloto, que servirían para validar la metodología propuesta. [fr] Le but de cet article est, déterminer la capacité de charge ou réception fonctionnelle, l’assimilation et rétablissement des marges et les cours de la rivière par le biais de la collecte d’informations de l’environnement: le

  20. Climate Change Impacts to North Pacific Pelagic Habitat Are Projected to Lower Carrying Capacity

    Science.gov (United States)

    Woodworth-Jefcoats, P. A.; Polovina, J. J.; Drazen, J.

    2016-02-01

    We use output from a suite of CMIP5 earth system models to explore the impacts of climate change on marine fisheries over the 21st century. Ocean temperatures from both the historical and RCP 8.5 projections are integrated over the upper 200 m of the water column to characterize thermal habitat in the epipelagic realm. We find that across all models the projected temperature increases lead to a redistribution of thermal habitat: temperatures that currently represent the majority of North Pacific pelagic habitat are replaced by temperatures several degrees warmer. Additionally, all models project the emergence of new thermal habitat that exceeds present-day maximum temperatures. Spatially, present-day thermal habitat retreats northward and contracts eastward as warmer habitat in the southern and western North Pacific expands. In addition to these changes in thermal habitat, zooplankton densities are projected to decline across much of the North Pacific. Taken together, warming temperatures and declining zooplankton densities create the potential for mismatches in metabolic demand and supply through the 21st century. We find that carrying capacity for tropical tunas and other commercially valuable pelagic fish may be especially vulnerable to the impacts of climate change. The waters projected to see the greatest redistribution of thermal habitat and greatest declines in zooplankton densities are primarily those targeted by the Hawaii-based and international longline fleets. Fishery managers around the North Pacific will need to incorporate these impacts of climate change into future management strategies.

  1. Multiple Carrying Capacities from a management-oriented perspective to operationalize sustainable tourism in protected areas.

    Science.gov (United States)

    Salerno, Franco; Viviano, Gaetano; Manfredi, Emanuela C; Caroli, Paolo; Thakuri, Sudeep; Tartari, Gianni

    2013-10-15

    This article describes how the concept of Tourism Carrying Capacity (TCC) has shifted from a uni-dimensional approach to incorporating environmental, social and political aspects. This shift is demonstrated by a study of a large, internationally popular protected area used by trekkers, the Mt. Everest Region, where qualitative data collected from visitors was combined with environmental modeling using a participatory framework. Tourist satisfaction showed positive margins for further tourist industry expansion, but current environmental conditions limit growth and further development. Space and time dimensions were also considered. We observed that the limits on growth and further development can be manipulated, with a certain degree of flexibility, through investments and regulatory measures. We hypothesized that TCC can play an important role in the management of protected areas only if it is viewed as a systematic, strategic policy tool within a planning process rather than as a unique, intrinsic number that is not modifiable. We conclude that to translate the strategy into action using standard measures, further investigation is needed to balance the various TCC components as a part of a decision-making framework that includes the integration of different cultural approaches and policy needs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Temperature dependences of growth rates and carrying capacities of marine bacteria depart from metabolic theoretical predictions

    KAUST Repository

    Huete-Stauffer, Tamara Megan

    2015-09-11

    Using the metabolic theory of ecology (MTE) framework, we evaluated over a whole annual cycle the monthly responses to temperature of the growth rates (μ) and carrying capacities (K) of heterotrophic bacterioplankton at a temperate coastal site. We used experimental incubations spanning 6oC with bacterial physiological groups identified by flow cytometry according to membrane integrity (live), nucleic acid content (HNA and LNA) and respiratory activity (CTC+). The temperature dependence of μat the exponential phase of growth was summarized by the activation energy (E), which was variable (-0.52 to 0.72 eV) but followed a seasonal pattern, only reaching the hypothesized value for aerobic heterotrophs of 0.65 eV during the spring bloom for the most active bacterial groups (live, HNA, CTC+). K (i.e. maximum experimental abundance) peaked at 4 × 106 cells mL-1 and generally covaried with μbut, contrary to MTE predictions, it did not decrease consistently with temperature. In the case of live cells, the responses of μand K to temperature were positively correlated and related to seasonal changes in substrate availability, indicating that the responses of bacteria to warming are far from homogeneous and poorly explained by MTE at our site. © FEMS 2015.

  3. Assessing the air pollution carrying capacity of the northern Puget Sound region: an application of TAPAS

    Energy Technology Data Exchange (ETDEWEB)

    Wood, M.C.; Childs J.E.; Marlatt, W.E.

    1980-09-01

    The technique discussed, the Topographic Air Pollution Analysis System (TAPAS), was developed to provide valid information on the dispersion capability of the lower atmosphere in areas characterized by complex terrain features. A study was undertaken to assess the air quality (SO/sub 2/) impacts associated with energy development in the region and to determine the constraints on energy development due to regulated limitations on the amount of air quality degradation allowable in the area. The emission constraint analysis for the northern Puget Sound region indicated that total SO/sub 2/ emissions in the core area (on an annual basis) are less than half of the amount that could be tolerated in the entire core region while maintaining ambient concentrations within state and federal annual average limitations. However, comparison of source characteristics with source location and grid cell emission restrictions indicated that localized areas adjacent to the major point sources are already far in excess of the SO/sub 2/ carrying capacity. This conclusion is supported by air quality monitoring data that indicate state standard violations at several receptor locations within the study area. The annual maps of wind patterns and PI-Matrix values show areas of both good and poor dispersion characteristics under the most prevalent flow conditions.

  4. Cultural carrying capacity: Organ donation advocacy, discursive framing, and social media engagement.

    Science.gov (United States)

    Bail, Christopher A

    2016-09-01

    Social media sites such as Facebook have become a powerful tool for public health outreach because they enable advocacy organizations to influence the rapidly increasing number of people who frequent these forums. Yet the very open-ness of social media sites creates fierce competition for public attention. The vast majority of social media messages provoke little or no reaction because of the sheer volume of information that confronts the typical social media user each day. In this article, I present a theory of the "cultural carrying capacity" of social media messaging campaigns. I argue that advocacy organizations inspire more endorsements, comments, and shares by social media users if they diversify the discursive content of their messages. Yet too much diversification creates large, disconnected audiences that lack the sense of shared purpose necessary to sustain an online movement. To evaluate this theory, I created a Facebook application that collects social media posts produced by forty-two organ donation advocacy organizations over 1.5 years, as well as supplemental information about the organization, its audience, and the broader social context in which they interact. Time series models provide strong evidence for my theory net of demographic characteristics of social media users, the resources and tactics of each organization, and broader external factors. I conclude by discussing the implications of these findings for public health, cultural sociology, and the nascent field of computational social science. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Benchmarking the Enrolment Structure of an Educational System without Exceeding the Carrying Capacity Requirement

    Directory of Open Access Journals (Sweden)

    Virtue Uwabomwen EKHOSUEHI

    2013-12-01

    Full Text Available In this paper, we propose an enrolment projection method based on the carrying capacity of the educational system. The method is a refinement of the recruitment control strategy proposed in the literature. We implement our proposed method using enrolment data from a university setting. The results obtained by extrapolating the short-term shifts in enrolment structure reflect the normal progression pattern in the system. Normal 0 false false false EN-US X-NONE AR-SA /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";}

  6. Experimental Study of Load Carrying Capacity of Point Contacts at Zero Entrainment Velocity

    Science.gov (United States)

    Shogin, B. A.; Jones, W. R., Jr.; Kingsbury, E. P.; Jansen, M. J.; Prahl, J. M.

    1998-01-01

    A capacitance technique was used to monitor the film thickness separating two steel balls while subjecting the ball-ball contact to highly stressed, zero entrainment velocity conditions. Tests were performed in a nitrogen atmosphere and utilized 52100 steel balls and a polyalphaolefin lubricant. Capacitance to film thickness accuracy was verified under pure rolling conditions using established EHL theory. Zero entrainment velocity tests were performed at sliding speeds from 6.0 to 10.0 m/s and for sustained amounts of time to 28.8 min. The protective lubricant film separating the specimens at zero entrainment velocity had a film thickness between 0.10 to 0.14 microns (4 to 6 micro in.), which corresponded to a k value of 4. The formation of an immobile surface film formed by lubricant entrapment is discussed as an explanation of the load carrying capacity at zero entrainment velocity conditions, relevant to the ball-ball contacts occurring in retainerless ball bearings.

  7. (ANTI)PETER Principle - Discrete (INVERSE) Logistic Equation with Imprecisely Estimated and Stimulated Carrying Capacity

    CERN Document Server

    Pankovic, V; Glavatovic, R

    2009-01-01

    In this work we consider the Peter principle and anti-Peter principle as the discrete logistic and discrete inverse logistic equation. Especially we discuss imprecisely estimated (by hierarchical control mechanism) carrying capacity, i.e. boundary (in)competence level of a hierarchy member. It implies that Peter principle holds two sub-principles. In the first one objective boundary competence level is increased for estimation error. In the second one objective boundary competence level is decreased for estimation error. Similarly, anti-Peter principle holds two sub-principles too. All this implies that paradoxical situations that follow from Peter and anti-Peter principle can be simply removed by decrease of the error of hierarchical (social) control. Also we discuss cases by Peter principle when error of the boundary competence level by estimation grows up. (Then, in fact, there is no estimation error but stimulation of the boundary level by control mechanism.) By first Peter sub-principle it implies anarch...

  8. Screening for EIA in India: enhancing effectiveness through ecological carrying capacity approach.

    Science.gov (United States)

    Rajaram, T; Das, Ashutosh

    2011-01-01

    Developing countries across the world have embraced the policy of high economic growth as a means to reduce poverty. This economic growth largely based on industrial output is fast degrading the ecosystems, jeopardizing their long term sustainability. Environmental Impact Assessment (EIA) has long been recognized as a tool which can help in protecting the ecosystems and aid sustainable development. The Screening guidelines for EIA reflect the level of commitment the nation displays towards tightening its environmental protection system. The paper analyses the screening process for EIA in India and dissects the rationale behind the exclusions and thresholds set in the screening process. The screening process in India is compared with that of the European Union with the aim of understanding the extent of deviations from a screening approach in the context of better economic development. It is found that the Indian system excludes many activities from the purview of screening itself when compared to the EU. The constraints responsible for these exclusions are discussed and the shortcomings of the current command and control system of environmental management in India are also explained. It is suggested that an ecosystem carrying capacity based management system can provide significant inputs to enhance the effectiveness of EIA process from screening to monitoring.

  9. Human embryonic stem cells carrying mutations for severe genetic disorders.

    Science.gov (United States)

    Frumkin, Tsvia; Malcov, Mira; Telias, Michael; Gold, Veronica; Schwartz, Tamar; Azem, Foad; Amit, Ami; Yaron, Yuval; Ben-Yosef, Dalit

    2010-04-01

    Human embryonic stem cells (HESCs) carrying specific mutations potentially provide a valuable tool for studying genetic disorders in humans. One preferable approach for obtaining these cell lines is by deriving them from affected preimplantation genetically diagnosed embryos. These unique cells are especially important for modeling human genetic disorders for which there are no adequate research models. They can be further used to gain new insights into developmentally regulated events that occur during human embryo development and that are responsible for the manifestation of genetically inherited disorders. They also have great value for the exploration of new therapeutic protocols, including gene-therapy-based treatments and disease-oriented drug screening and discovery. Here, we report the establishment of 15 different mutant human embryonic stem cell lines derived from genetically affected embryos, all donated by couples undergoing preimplantation genetic diagnosis in our in vitro fertilization unit. For further information regarding access to HESC lines from our repository, for research purposes, please email dalitb@tasmc.health.gov.il.

  10. 土地综合承载力研究现状%Overview of the Land Comprehensive Carrying Capacity

    Institute of Scientific and Technical Information of China (English)

    刘梦

    2014-01-01

    The land comprehensive carrying capacity refers to the economic carrying capacity, social carrying capacity and ecological carrying capacity of a region��s land. Based on a review of the land comprehensive carrying capacity re⁃search, its characteristics such as the monotone research method, the incomprehensive content despite the hierarchical re⁃gional research as well as the singleness of research object were summerized, pointing out that the method of constructing the index system is the major method to evaluate carrying capacity of the land. The method of improving the land compre⁃hensive carrying capacity and the prospection of the land comprehensive carrying capacity were discussed, and the con⁃clusion that the new trend is to combine the“qualitative”with“quantitative”and to broaden the range of research was given.%土地综合承载力是一个区域土地经济承载力、社会承载力以及生态承载力的综合能力的反映。在回顾土地综合承载力研究的基础上,总结其研究方法不够多样化、研究区域具有层次性但研究内容不够全面、研究对象较单一等特点,指出通过构建指标体系的方法是评价土地综合承载力的主流方法,并提出了提高土地综合承载力的方法,对土地综合承载力研究进行了展望,认为“定性”与“定量”结合、拓宽研究范围等将成为研究新趋势。

  11. Proactive monitoring and adaptive management of social carrying capacity in Arches National Park: an application of computer simulation modeling.

    Science.gov (United States)

    Lawson, Steven R; Manning, Robert E; Valliere, William A; Wang, Benjamin

    2003-07-01

    Public visits to parks and protected areas continue to increase and may threaten the integrity of natural and cultural resources and the quality of the visitor experience. Scientists and managers have adopted the concept of carrying capacity to address the impacts of visitor use. In the context of outdoor recreation, the social component of carrying capacity refers to the level of visitor use that can be accommodated in parks and protected areas without diminishing the quality of the visitor experience to an unacceptable degree. This study expands and illustrates the use of computer simulation modeling as a tool for proactive monitoring and adaptive management of social carrying capacity at Arches National Park. A travel simulation model of daily visitor use throughout the Park's road and trail network and at selected attraction sites was developed, and simulations were conducted to estimate a daily social carrying capacity for Delicate Arch, an attraction site in Arches National Park, and for the Park as a whole. Further, a series of simulations were conducted to estimate the effect of a mandatory shuttle bus system on daily social carrying capacity of Delicate Arch to illustrate how computer simulation modeling can be used as a tool to facilitate adaptive management of social carrying capacity.

  12. Estimating habitat carrying capacity for migrating and wintering waterfowl: Considerations, pitfalls and improvements

    Science.gov (United States)

    Williams, Christopher; Dugger, Bruce D.; Brasher, Michael G.; Coluccy, John M.; Cramer, Dane M.; Eadie, John M.; Gray, Matthew J.; Hagy, Heath M.; Livolsi, Mark; McWilliams, Scott R.; Petrie, Matthew; Soulliere, Gregory J.; Tirpak, John M.; Webb, Elisabeth B.

    2014-01-01

    Population-based habitat conservation planning for migrating and wintering waterfowl in North America is carried out by habitat Joint Venture (JV) initiatives and is based on the premise that food can limit demography (i.e. food limitation hypothesis). Consequently, planners use bioenergetic models to estimate food (energy) availability and population-level energy demands at appropriate spatial and temporal scales, and translate these values into regional habitat objectives. While simple in principle, there are both empirical and theoretical challenges associated with calculating energy supply and demand including: 1) estimating food availability, 2) estimating the energy content of specific foods, 3) extrapolating site-specific estimates of food availability to landscapes for focal species, 4) applicability of estimates from a single species to other species, 5) estimating resting metabolic rate, 6) estimating cost of daily behaviours, and 7) estimating costs of thermoregulation or tissue synthesis. Most models being used are daily ration models (DRMs) whose set of simplifying assumptions are well established and whose use is widely accepted and feasible given the empirical data available to populate such models. However, DRMs do not link habitat objectives to metrics of ultimate ecological importance such as individual body condition or survival, and largely only consider food-producing habitats. Agent-based models (ABMs) provide a possible alternative for creating more biologically realistic models under some conditions; however, ABMs require different types of empirical inputs, many of which have yet to be estimated for key North American waterfowl. Decisions about how JVs can best proceed with habitat conservation would benefit from the use of sensitivity analyses that could identify the empirical and theoretical uncertainties that have the greatest influence on efforts to estimate habitat carrying capacity. Development of ABMs at

  13. Biofilm growth mode promotes maximum carrying capacity and community stability during product inhibition syntrophy.

    Science.gov (United States)

    Brileya, Kristen A; Camilleri, Laura B; Zane, Grant M; Wall, Judy D; Fields, Matthew W

    2014-01-01

    Sulfate-reducing bacteria (SRB) can interact syntrophically with other community members in the absence of sulfate, and interactions with hydrogen-consuming methanogens are beneficial when these archaea consume potentially inhibitory H2 produced by the SRB. A dual continuous culture approach was used to characterize population structure within a syntrophic biofilm formed by the SRB Desulfovibrio vulgaris Hildenborough and the methanogenic archaeum Methanococcus maripaludis. Under the tested conditions, monocultures of D. vulgaris formed thin, stable biofilms, but monoculture M. maripaludis did not. Microscopy of intact syntrophic biofilm confirmed that D. vulgaris formed a scaffold for the biofilm, while intermediate and steady-state images revealed that M. maripaludis joined the biofilm later, likely in response to H2 produced by the SRB. Close interactions in structured biofilm allowed efficient transfer of H2 to M. maripaludis, and H2 was only detected in cocultures with a mutant SRB that was deficient in biofilm formation (ΔpilA). M. maripaludis produced more carbohydrate (uronic acid, hexose, and pentose) as a monoculture compared to total coculture biofilm, and this suggested an altered carbon flux during syntrophy. The syntrophic biofilm was structured into ridges (∼300 × 50 μm) and models predicted lactate limitation at ∼50 μm biofilm depth. The biofilm had structure that likely facilitated mass transfer of H2 and lactate, yet maximized biomass with a more even population composition (number of each organism) when compared to the bulk-phase community. Total biomass protein was equivalent in lactate-limited and lactate-excess conditions when a biofilm was present, but in the absence of biofilm, total biomass protein was significantly reduced. The results suggest that multispecies biofilms create an environment conducive to resource sharing, resulting in increased biomass retention, or carrying capacity, for cooperative populations.

  14. Decline in territory size and fecundity as a response to carrying capacity in an endangered songbird.

    Science.gov (United States)

    Hartmann, Stefanie A; Oppel, Steffen; Segelbacher, Gernot; Juiña, Mery E; Schaefer, H Martin

    2017-02-01

    Density-dependent processes are fundamental mechanisms for the regulation of populations. Ecological theories differ in their predictions on whether increasing population density leads to individual adjustments of survival and reproductive output or to dominance and monopolization of resources. Here, we use a natural experiment to examine which factors limit population growth in the only remaining population of the endangered pale-headed brush finch (Atlapetes pallidiceps). For three distinct phases (a phase of population suppression, 2001-2002; expansion due to conservation management, 2003-2008; and equilibrium phase, 2009-2014), we estimated demographic parameters with an integrated population model using population size, the proportion of successfully breeding pairs and their productivity, territory size, and mark-recapture data of adult birds. A low proportion of successful breeders due to brood parasitism (0.42, 95% credible interval 0.26-0.59) limited population growth before 2003; subsequent culling of the brood parasite resulted in a two-fold increase of the proportion of successful breeders during the 'expansion phase'. When the population approached the carrying capacity of its habitat, territory size declined by more than 50% and fecundity declined from 1.9 (1.54-2.27) to 1.3 (1.12-1.53) chicks per breeding pair, but the proportion of successful breeders remained constant (expansion phase: 0.85; 0.76-0.93; equilibrium phase: 0.86; 0.79-0.92). This study demonstrates that limiting resources can lead to individual adjustments instead of despotic behavior, and the individual reduction of reproductive output at high population densities is consistent with the slow life-history of many tropical species.

  15. Biofilm growth mode promotes maximum carrying capacity and community stability during product inhibition syntrophy

    Directory of Open Access Journals (Sweden)

    Kristen Annis Brileya

    2014-12-01

    Full Text Available Sulfate-reducing bacteria (SRB can interact syntrophically with other community members in the absence of sulfate, and interactions with hydrogen-consuming methanogens are beneficial when these archaea consume potentially inhibitory H2 produced by the SRB. A dual continuous culture approach was used to characterize population structure within a syntrophic biofilm formed by the SRB Desulfovibrio vulgaris Hildenborough and the methanogenic archaeum Methanococcus maripaludis. Under the tested conditions, monocultures of D. vulgaris formed thin, stable biofilms, but monoculture M. maripaludis did not. Microscopy of intact syntrophic biofilm confirmed that D. vulgaris formed a scaffold for the biofilm, while intermediate and steady-state images revealed that M. maripaludis joined the biofilm later, likely in response to H2 produced by the SRB. Close interactions in structured biofilm allowed efficient transfer of H2 to M. maripaludis, and H2 was only detected in cocultures with a mutant SRB that was deficient in biofilm formation ( delta pilA. M. maripaludis produced more carbohydrate (uronic acid, hexose, and pentose as a monoculture compared to total coculture biofilm, and this suggested an altered carbon flux during syntrophy. The syntrophic biofilm was structured into ridges (~300 x 50 um and models predicted lactate limitation at approximately 50 um biofilm depth. The biofilm had structure that likely facilitated mass transfer of H2 and lactate, yet maximized biomass with a more even population composition (number of each organism when compared to the bulk-phase community. Total biomass protein was equivalent in lactate-limited and lactate-excess conditions when a biofilm was present, but in the absence of biofilm, total biomass protein was significantly reduced. The results suggest that multispecies biofilms create an environment conducive to resource sharing, resulting in increased biomass retention, or carrying capacity, for cooperative

  16. Psychophysical determination of load carrying capacity for a 1-h work period by Chinese males.

    Science.gov (United States)

    Wu, S P; Chen, C C

    2001-09-15

    This study used the psychophysical approach to examine the effects of container width, the presence or absence of container handles, and different load-carrying frequencies and distances on the maximum acceptable weight carried and the resulting response (heart rate and rating of perceived exertion) by well-conditioned males for a 1-h work period. After training, 12 male subjects performed a load-carrying task at knuckle height. Each subject performed 30 different carrying combinations. The conditions examined were container width, from 15.2 to 55.9 cm; carrying frequency, from 1 carry to 5 carries/min; and carrying distance from 1 to 6 m. The results were compared with prior studies and led to the following conclusions: (1) the use of container handles leads to the subjects carrying a significantly higher maximum acceptable weight than when containers do not have handles, which differs from the results of a previous study by Morrissey and Liou; (2) there were significant reductions in the maximum acceptable carrying weight with increases in container width, frequency and distance; (3) the presence or absence of container handles, different frequencies and load-carrying distances had significant effects on heart rate, although the effect of container width was not significant. In addition, the various frequencies and distances for load carrying had significant interaction effects on heart rate; (4) the effects of various frequencies and load-carrying distances on the rating of perceived exertion were statistically significant. The most stressed body parts were the wrists and arms.

  17. Changes in agriculture and abundance of snow geese affect carrying capacity of sandhill cranes in Nebraska

    Science.gov (United States)

    Pearse, A.T.; Krapu, G.L.; Brandt, D.A.; Kinzel, P.J.

    2010-01-01

    The central Platte River valley (CPRV) in Nebraska, USA, is a key spring-staging area for approximately 80 of the midcontinent population of sandhill cranes (Grus canadensis; hereafter cranes). Evidence that staging cranes acquired less lipid reserves during the 1990s compared to the late 1970s and increases in use of the CPRV by snow geese (Chen caerulescens) prompted us to investigate availability of waste corn and quantify spatial and temporal patterns of crane and waterfowl use of the region. We developed a predictive model to assess impacts of changes in availability of corn and snow goose abundance under past, present, and potential future conditions. Over a hypothetical 60-day staging period, predicted energy demand of cranes and waterfowl increased 87 between the late 1970s and 19982007, primarily because peak abundances of snow geese increased by 650,000 and cranes by 110,000. Compared to spring 1979, corn available when cranes arrived was 20 less in 1998 and 68 less in 1999; consequently, the area of cornfields required to meet crane needs increased from 14,464 ha in 1979 to 32,751 ha in 1998 and 90,559 ha in 1999. Using a pooled estimate of 88 kg/ha from springs 19981999 and 20052007, the area of cornfields needed to supply food requirements of cranes and waterfowl increased to 65,587 ha and was greatest in the eastern region of the CPRV, where an estimated 54 of cranes, 47 of Canada geese (Branta canadensis), 45 of greater white-fronted geese (Anser albifrons), and 46 of snow geese occurred during ground surveys. We estimated that a future reduction of 25 in available corn or cornfields would increase daily foraging flight distances of cranes by 2738. Crane use and ability of cranes to store lipid reserves in the CPRV could be reduced substantially if flight distance required to locate adequate corn exceeded a physiological maximum distance cranes could fly in search of food. Options to increase carrying capacity for cranes include increasing

  18. Strengthening Carrying Capacity of a Water Supply System under Climate Change with the Drought Early Warning System

    Science.gov (United States)

    Huang, Syujie; Liu, Tzuming; Li, Minghsu; Tung, Chingpin

    2016-04-01

    The carrying capacity of a water supply system is the maximal probable water supply amount under an acceptable risk which is related to the systematic combination of hydrology conditions, climatic conditions, and water infrastructures, for instance, reservoirs, weirs, and water treatment plants. Due to long-term imbalance of water supply and demand during the drought seasons, the carrying capacity of a water supply system may be affected gradually with more extreme climate events resulting from the climate change. To evaluate the carrying capacity of the water supply system under climate change, three major steps to build adaptation capacity under climate change are adopted, including problem identification and goal setting, current risk assessment, and future risk assessment. The carrying capacities for current climate condition and future climate condition were estimated respectively. The early warning system was taken as the effective measure to strengthen the carrying capacity for the uncertain changing climate. The water supply system of Chuoshui River basin in Taiwan is used as the case study. The system dynamics modeling software, Vensim, was used to build the water resources allocation model for Chuoshui River basin. To apply the seasonal climate forecasts released from Taiwan Central Weather Bureau (CWB) on modeling, a weather generator is adopted to generate daily weather data for the input of the hydrological component of GWLF model, to project inflows with the lead time of three months. Consequently, the water shortages with and without a drought early warning system were estimated to evaluate the effectiveness of a drought early warning system under climate change. Keywords: Climate change, Carrying capacity, Risk Assessment, Seasonal Climate Forecasts, Drought Early Warning System

  19. Recreation Carrying Capacity Facts and Considerations. Report 11. Surry Mountain Lake Project Area.

    Science.gov (United States)

    1980-07-01

    examines possible solutions; and it does not include the methodologies for deter- mining and monitoring social and resource capacity. For these reasons...Point Overcrowding observed and o Determine social capac- Picnic Areas reported during the User Survey. ity of these areas. o Place only the...area. r Consider the potential for site hardening and provide agressive maintenancce and restiration. 40 Possible Area/Subject Problem/Situation

  20. RESEARCH ON THE POPULATION CARRYING CAPACITY OF THE LAND RESOURCES IN THE ECONOMIC AREA OF ZHUJIANG DELTA

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The authors once made a preliminary research on population carrying capacity of the land in the Economic Area of Zhujiang Delta (EAZD for short) in 1995, and reckoned that the ultimate population in this region will be 23 550 thousand by year of 2000. While the population in being in EAZD was 22.62 million in 1999. This accords with the prefigured result in the rough from the point of view of development. According to the data of plow land resources from the 2000 Statistical Yearbook of EAZD and the study on the population-foodstuff-plow land relationship, this paper calculates the productive potential of plow land and the population carrying capacity of land by year of 2010, and puts forward the countermeasures for improving the population carrying capacity of land in this region.

  1. Simple Evaluation of Load-Carrying Capacity of Multi-Span Folding Bridges based on Floating Supports

    Directory of Open Access Journals (Sweden)

    Jan Marszałek

    2014-12-01

    Full Text Available [b]Abstract[/b]. The papers covers simple evaluation of load-carrying capacity of multi-span folding bridges based on floating supports. Combined bridges built in this approach, could be used as a temporary crossing. The methodology of this evaluation is shown graphically on the basis of designed nomograms for two existing bridge structures i.e. MS-54 and DMS-65, mounted on rigid and floating supports. These nomograms facilitate the simple and fast determination of the impact of changing fixed support into floating support with different bridge length spans on the carrying capacity of the bridge. The paper also presents the influence of long-term use (enlarging the mounting backlash in the joints of these structures on the carrying capacity of the bridge.[b]Keywords[/b]: building, folding bridges, nomograms, assembly clearances

  2. A model to assess fundamental and realized carrying capacities of island ecosystem: A case study in the southern Miaodao Archipelago of China

    Institute of Scientific and Technical Information of China (English)

    SHI Honghua; SHEN Chengcheng; ZHENG Wei; LI Fen; WANG Xiaoli; CHI Yuan; GUO Zhen

    2016-01-01

    Research on carrying capacity, aiming at maintaining the limited ability of the Earth's life supporting system to sustain human development, requires a comprehensive and ecosystem-based approach to monitor and assess the localized sustainability of coupled social and ecological systems. A definition termed the ecosystem-based carrying capacity of island (EBCCI) was developed in this paper of which the indices of fundamental and realized carrying capacities of island (FCCI and RCCI) were highlighted to emphasize the inter-dependencies between social systems and ecological systems. In order to avoid the difficulties and uncertainties of direct assessment, the related assessment model was established on the basis of synthetic evaluation of inherent and external factors affecting the EBCCI. The southern Miaodao Archipelago (SMA) located in the intersection of the Bohai Sea and the Yellow Sea, China, was taken as a typical example to acquire integrated recognition of the island ecosystem and its carrying capacity so as to discuss its sustainable development. The index scores of FCCI and RCCI in the SMA were 0.818 5 and 0.712 9 out of 1.0, respectively, with acceptable uncertainties. The results showed a relatively well capacity to sustain progress and relatively well realization of the carrying capacity of island ecosystem, owing to a well capacity of ecologically regulating, general performance of both ecologically supporting and resource provisioning, and a relatively high level of social supporting system. The study implied that it was critical to optimize the inter-dependencies and to sustain the relative balance between social systems and ecological systems so as to improve the RCCI and further facilitate the sustainability of SMA. The approach proposed in this paper provides a powerful tool which is well applicative to the regional level of an oceanic island or archipelago to study the sustainable development and can be further popularized to the coastal zone.

  3. Glove powder's carrying capacity for latex protein: analysis using the ASTM ELISA test.

    Science.gov (United States)

    Beezhold, D; Horton, K; Hickey, V; Daddona, J; Kostyal, D

    2003-01-01

    Glove donning powders carry latex proteins and disperse them into the workplace environment. We have used the ASTM D6499 ELISA to quantify the amount of latex antigen bound to and carried by glove powders. We could differentiate between a small amount of protein actually bound to the powders and a larger amount carried by the powder. Enhanced binding of a major allergen, Hev b 5, to the starch powders was demonstrated by Western blot. The D6499 ELISA is able to measure total latex antigen, soluble and powder bound, simultaneously without the need to centrifuge the samples.

  4. Load-carrying capacity test of a long-span timber truss

    OpenAIRE

    Branco, Jorge M.; Varum, Humberto; Ramisote, Vitor; Costa, Aníbal

    2016-01-01

    The aim of this work was to study the behavior of existing timber trusses in order to improve the knowledge that may support engineers in the definition of more adequate restoration interventions in old buildings, particularly of long-span timber structures, as industrial or monumental constructions. For this purpose, a cyclic load-carrying test was carried out on a full-scale timber planar truss rescued from an old industrial roof structure. Before the tests, an accurate geometrical characte...

  5. A Study on Load Carrying Capacity of Fly Ash Based Polymer Concrete Columns Strengthened Using Double Layer GFRP Wrapping

    Directory of Open Access Journals (Sweden)

    S. Nagan

    2014-01-01

    Full Text Available This paper investigates the suitability of glass fiber reinforced polymer (GFRP sheets in strengthening of fly ash based polymer members under compression. Experimental results revealed that load carrying capacity of the confined columns increases with GFRP sheets wrapping. Altogether 18 specimens of M30 and G30 grade short columns were fabricated. The G30 specimens were prepared separately in 8 molarity and 12 molarity of sodium hydroxide concentration. Twelve specimens for low calcium fly ash based reinforced polymer concrete and six specimens of ordinary Portland cement reinforced concrete were cast. Three specimens from each molarity fly ash based reinforced polymer concrete and ordinary Portland cement reinforced concrete were wrapped with double layer of GFRP sheets. The load carrying capacity of fly ash based polymer concrete was tested and compared with control specimens. The results show increase in load carrying capacity and ductility index for all strengthened elements. The maximum increase in load carrying capacity was 68.53% and is observed in strengthened G30 specimens.

  6. Alveolar gas exchange and tissue oxygenation during incremental treadmill exercise, and their associations with blood O(2) carrying capacity.

    Science.gov (United States)

    Rissanen, Antti-Pekka E; Tikkanen, Heikki O; Koponen, Anne S; Aho, Jyrki M; Hägglund, Harriet; Lindholm, Harri; Peltonen, Juha E

    2012-01-01

    The magnitude and timing of oxygenation responses in highly active leg muscle, less active arm muscle, and cerebral tissue, have not been studied with simultaneous alveolar gas exchange measurement during incremental treadmill exercise. Nor is it known, if blood O(2) carrying capacity affects the tissue-specific oxygenation responses. Thus, we investigated alveolar gas exchange and tissue (m. vastus lateralis, m. biceps brachii, cerebral cortex) oxygenation during incremental treadmill exercise until volitional fatigue, and their associations with blood O(2) carrying capacity in 22 healthy men. Alveolar gas exchange was measured, and near-infrared spectroscopy (NIRS) was used to monitor relative concentration changes in oxy- (Δ[O(2)Hb]), deoxy- (Δ[HHb]) and total hemoglobin (Δ[tHb]), and tissue saturation index (TSI). NIRS inflection points (NIP), reflecting changes in tissue-specific oxygenation, were determined and their coincidence with ventilatory thresholds [anaerobic threshold (AT), respiratory compensation point (RC); V-slope method] was examined. Blood O(2) carrying capacity [total hemoglobin mass (tHb-mass)] was determined with the CO-rebreathing method. In all tissues, NIPs coincided with AT, whereas RC was followed by NIPs. High tHb-mass associated with leg muscle deoxygenation at peak exercise (e.g., Δ[HHb] from baseline walking to peak exercise vs. tHb-mass: r = 0.64, p capacity for blood O(2) carrying was associated with a high level of m. vastus lateralis deoxygenation at peak exercise.

  7. Influence of wave and current flow on sediment-carrying capacity and sediment flux at the water-sediment interface.

    Science.gov (United States)

    Zheng, Jun; Li, Ruijie; Yu, Yonghai; Suo, Anning

    2014-01-01

    In nearshore waters, spatial and temporal scales of waves, tidal currents, and circulation patterns vary greatly. It is, therefore, difficult to combine these factors' effects when trying to predict sediment transport processes. This paper proposes the concept of significant wave velocity, which combines the effects of waves, tides, and ocean currents using the horizontal kinetic energy superposition principle. Through a comparison of the relationship between shear stress at the water-sediment interface and sediment-carrying capacity, assuming equilibrium sediment flux, a new formula for sediment-carrying capacity, which incorporates the concept of significant wave velocities, is derived. Sediment-carrying capacity is a function of the critical velocity, which increases with water depth and decreases with increasing relative roughness of the sea bed. Finally, data from field observation stations and simulations are used to test the proposed formula. The results show that the new formula is in good agreement with both field and simulation data. This new formula for sediment-carrying capacity can be used to simulate nearshore sediment transport.

  8. Student Responses to a Hands-On Kinesthetic Lecture Activity for Learning about the Oxygen Carrying Capacity of Blood

    Science.gov (United States)

    Breckler, Jennifer; Yu, Justin R.

    2011-01-01

    This article describes a new hands-on, or "kinesthetic," activity for use in a physiology lecture hall to help students comprehend an important concept in cardiopulmonary physiology known as oxygen carrying capacity. One impetus for designing this activity was to address the needs of students who have a preference for kinesthetic…

  9. Population ecology and carrying capacity estimates for large ungulates at Sully's Hill National Game Preserve, North Dakota

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a proposal for a two year project with the University of North Dakota. The end product of this research will be a detailed model of the carrying capacity for...

  10. 49 CFR 571.120 - Tire selection and rims and motor home/recreation vehicle trailer load carrying capacity...

    Science.gov (United States)

    2010-10-01

    ... words “IMPORTANT—USE OF SPARE TIRE” in letters not less than 9 millimeters high. S8.2Supplementary... of on-board potable water must be treated as cargo. S10.4.3The RV load carrying capacity labels... belt equipped seating positions. (e) The statement: “CAUTION: A full load of water equals XXX kg or XXX...

  11. Parametrical Method for Determining Optimal Ship Carrying Capacity and Performance of Handling Equipment

    Directory of Open Access Journals (Sweden)

    Michalski Jan P.

    2016-04-01

    Full Text Available The paper presents a method of evaluating the optimal value of the cargo ships deadweight and the coupled optimal value of cargo handling capacity. The method may be useful at the stage of establishing the main owners requirements concerning the ship design parameters as well as for choosing a proper second hand ship for a given transportation task. The deadweight and the capacity are determined on the basis of a selected economic measure of the transport effectiveness of ship – the Required Freight Rate. The mathematical model of the problem is of a deterministic character and the simplifying assumptions are justified for ships operating in the liner trade. The assumptions are so selected that solution of the problem is obtained in analytical closed form. The presented method can be useful for application in the preliminary ship design or in the simulation of pre-investment transportation task studies.

  12. Load Carrying Capacity of Keyed Joints Reinforced with High Strength Wire Rope Loops

    DEFF Research Database (Denmark)

    Jørgensen, Henrik Brøner; Hoang, Linh Cao

    Vertical shear connections between precast concrete wall elements are usually made as keyed joints reinforced with overlapping U-bars. The overlapping U-bars form a cylindrical core in which the locking bar is placed and the connection is subsequently grouted with mortar. A more construction...... friendly shear connection can be obtained by replacing the U-bars with high strength looped wire ropes. The wire ropes have the advantage of being flexible (they have virtually no bending stiffness) which makes installation of wall elements much easier. The looped wire ropes are usually pre-installed in so...... the shear capacity of wire loop connections. Tests have shown that the shear capacity of such joints – due to the relatively high tensile strength of the wire ropes - is more prone to be governed by fracture of the joint mortar in combination with yielding of the locking bar. To model this type of failure...

  13. Load-carrying capacity of lightly reinforced, prefabricated walls of lightweight aggregate concrete with open structure

    DEFF Research Database (Denmark)

    Goltermann, Per

    2009-01-01

    The paper presents and evaluates the results of a coordinated testing of prefabricated, lightly reinforced walls of lightweight aggregate concrete with open structure. The coordinated testing covers all wall productions in Denmark and will therefore provide a representative assessment of the qual...... of the quality actually produced. Existing and new formulas for the capacity are evaluated by comparison to the test results and a new model with a good correlation with the test results is presented....

  14. A Comparative Analysis on Assessment of Land Carrying Capacity with Ecological Footprint Analysis and Index System Method.

    Science.gov (United States)

    Qian, Yao; Tang, Lina; Qiu, Quanyi; Xu, Tong; Liao, Jiangfu

    2015-01-01

    Land carrying capacity (LCC) explains whether the local land resources are effectively used to support economic activities and/or human population. LCC can be evaluated commonly with two approaches, namely ecological footprint analysis (EFA) and the index system method (ISM). EFA is helpful to investigate the effects of different land categories whereas ISM can be used to evaluate the contributions of social, environmental, and economic factors. Here we compared the two LCC-evaluation approaches with data collected from Xiamen City, a typical region where rapid economic growth and urbanization are found in China. The results show that LCC assessments with EFA and ISM not only complement each other but also are mutually supportive. Both assessments suggest that decreases in arable land and increasingly high energy consumption have major negative effects on LCC and threaten sustainable development for Xiamen City. It is important for the local policy makers, planners and designers to reduce ecological deficits by controlling fossil energy consumption, protecting arable land and forest land from converting into other land types, and slowing down the speed of urbanization, and to promote sustainability by controlling rural-to-urban immigration, increasing hazard-free treatment rate of household garbage, and raising energy consumption per unit industrial added value. Although EFA seems more appropriate for estimating LCC for a resource-output or self-sufficient region and ISM is more suitable for a resource-input region, both approaches should be employed when perform LCC assessment in any places around the world.

  15. A Comparative Analysis on Assessment of Land Carrying Capacity with Ecological Footprint Analysis and Index System Method.

    Directory of Open Access Journals (Sweden)

    Yao Qian

    Full Text Available Land carrying capacity (LCC explains whether the local land resources are effectively used to support economic activities and/or human population. LCC can be evaluated commonly with two approaches, namely ecological footprint analysis (EFA and the index system method (ISM. EFA is helpful to investigate the effects of different land categories whereas ISM can be used to evaluate the contributions of social, environmental, and economic factors. Here we compared the two LCC-evaluation approaches with data collected from Xiamen City, a typical region where rapid economic growth and urbanization are found in China. The results show that LCC assessments with EFA and ISM not only complement each other but also are mutually supportive. Both assessments suggest that decreases in arable land and increasingly high energy consumption have major negative effects on LCC and threaten sustainable development for Xiamen City. It is important for the local policy makers, planners and designers to reduce ecological deficits by controlling fossil energy consumption, protecting arable land and forest land from converting into other land types, and slowing down the speed of urbanization, and to promote sustainability by controlling rural-to-urban immigration, increasing hazard-free treatment rate of household garbage, and raising energy consumption per unit industrial added value. Although EFA seems more appropriate for estimating LCC for a resource-output or self-sufficient region and ISM is more suitable for a resource-input region, both approaches should be employed when perform LCC assessment in any places around the world.

  16. Analysis of Load-Carrying Capacity for Redundant Free-Floating Space Manipulators in Trajectory Tracking Task

    Directory of Open Access Journals (Sweden)

    Qingxuan Jia

    2014-01-01

    Full Text Available The aim of this paper is to analyze load-carrying capacity of redundant free-floating space manipulators (FFSM in trajectory tracking task. Combined with the analysis of influential factors in load-carrying process, evaluation of maximum load-carrying capacity (MLCC is described as multiconstrained nonlinear programming problem. An efficient algorithm based on repeated line search within discontinuous feasible region is presented to determine MLCC for a given trajectory of the end-effector and corresponding joint path. Then, considering the influence of MLCC caused by different initial configurations for the starting point of given trajectory, a kind of maximum payload initial configuration planning method is proposed by using PSO algorithm. Simulations are performed for a particular trajectory tracking task of the 7-DOF space manipulator, of which MLCC is evaluated quantitatively. By in-depth research of the simulation results, significant gap between the values of MLCC when using different initial configurations is analyzed, and the discontinuity of allowable load-carrying capacity is illustrated. The proposed analytical method can be taken as theoretical foundation of feasibility analysis, trajectory optimization, and optimal control of trajectory tracking task in on-orbit load-carrying operations.

  17. Environment Carrying Capacity in Developing Innovation Center of Micro Small Medium Enterprises (MSME in Kabupaten Pandeglang, Banten Province

    Directory of Open Access Journals (Sweden)

    Muhlisin

    2015-03-01

    Full Text Available The study aims to determine environmental carrying capacity strategies for developing MSMEs Innovation Center. The study research using quantitative descriptive method and instruments questionnaire given to stakeholders and government related to sheep and goats in the Juhut village, Pandeglang. Data collected was processed premises scoring and Analytical Hierarchy Process (AHP method used software of expert choice 11. The results showed that the Carrying Capacity levels of MSME was in the quite category, while aspect of facilitation as the highest proportions and the lowest was access to information. Innovation Center of MSME strategies are through the efforts increased Environment Carrying Capacity’s variables of Innovation Center of MSME are still lacking or not meet the standards through synergy efforts by Ministry of Research of Technology and Higher Education, Provincial Government. Of Banten, district/municipal government, Institute for Agricultural Technology of Banten, and universities.

  18. Natural Airfield Pavements, Load-Carrying Capacities There Of, Principles Of Construction And Operational Use

    Directory of Open Access Journals (Sweden)

    Nita Piotr

    2015-09-01

    Full Text Available The paper has been intended to present analytically derived relationships for aircraft wheels that move through the soil medium. The analyses have been conducted for both the rigid wheel and the pneumatic whell. The most fundamental principles of constructing natural(soil and sod/grass airfield pavements have been diccussed. Characteristic of soils typical of such pavements /surfaces have been defined. Proped are criteria for the evaluation of load-carring capacities of such pavements. The most essential principles that goven the operational use there of follow.

  19. Numerical study of regional environmental carrying capacity for livestock and poultry farming based on planting-breeding balance.

    Science.gov (United States)

    Peng, Lihong; Bai, Yu

    2013-09-01

    In consideration of the need to maintain planting-breeding balance, this article examines the capacity of the soil in Putian City, Fujian Province to absorb livestock and poultry excreta, and computes the environmental carrying capacity for livestock and poultry farming (ECCLPF) in each district of the city in terms of the fertility characteristics of the soil in the city, as well as its mix of crops cultivated and farming methods. On the basis of the computations, this work proceeds to classify the alarm grades of the city's environmental carrying capacity for livestock and poultry framing, and assess the environmental impact of the livestock and poultry farming industry. The results of our study indicate that, the city's ECCLPF ranges from 8.27 to 23.23 heads per ha when computed on the basis of nitrogen, and from 5.79 to 24.53 heads per ha when computed on the basis of phosphorus. A comparison between our research findings and the existing farming scale in Putian reveals that, in certain parts of the city, ECCLPF is overburdened to varying degrees. Specifically, Chengxiang District is severely overburdened, Hanjiang District and Meizhou Island have a level of overburdening between virtual overburdening and significant overburdening, Licheng District is virtually overburdened, and Xiuyu, Xianyou, and Bei'an Districts have not exceeded their environmental carrying capacity and therefore have varying levels of potential for growth.

  20. Numerical study of regional environmental carrying capacity for livestock and poultry farming based on planting-breeding balance

    Institute of Scientific and Technical Information of China (English)

    Lihong Peng; Yu Bai

    2013-01-01

    In consideration of the need to maintain planting-breeding balance,this article examines the capacity of the soil in Putian City,Fujian Province to absorb livestock and poultry excreta,and computes the environmental carrying capacity for livestock and poultry farming (ECCLPF) in each district of the city in terms of the fertility characteristics of the soil in the city,as well as its mix of crops cultivated and farming methods.On the basis of the computations,this work proceeds to classify the alarm grades of the city's environmental carrying capacity for livestock and poultry framing,and assess the environmental impact of the livestock and poultry farming industry.The results of our study indicate that,the city's ECCLPF ranges from 8.27 to 23.23 heads per ha when computed on the basis of nitrogen,and from 5.79 to 24.53 heads per ha when computed on the basis of phosphorus.A comparison between our research findings and the existing fanning scale in Putian reveals that,in certain parts of the city,ECCLPF is overburdened to varying degrees.Specifically,Chengxiang District is severely overburdened,Hanjiang District and Meizhou Island have a level of overburdening between virtual overburdening and significant overburdening,Licheng District is virtually overburdened,and Xiuyu,Xianyou,and Bei'an Districts have not exceeded their environmental carrying capacity and therefore have varying levels of potential for growth.

  1. 巫山县生态承载力研究%STUDY ON THE ECOLOGICAL CARRYING CAPACITY IN WUSHAN COUNTY

    Institute of Scientific and Technical Information of China (English)

    吴晓; 吴宜进

    2013-01-01

    Land resources are the carrier of all resources and environmental factors,which has played an extremely important role in the socio-economic operation.Wushan County is mainly mountainous,the land resources are very barren,the arable land which mostly is sloping land has a poor quality,and the soil erosion is much more serious than other areas.Due to the construction of the Three Gorges Project,a large number of immigrants need to build their new home in place.The pressure which is carried by land is surging.All of the above has hindered the sustainable socio-economic development in Wushan County.In recent years,scholars note that the rational utilization of land resources in Wushan County has a crucial importance on sustainable development and the coordinated development of the human-land relationship in Wushan County.Because of this,the scholars have conducted a preliminary study and have published a number of papers.The number of the research papers which is mainly about ecological footprint of the county scale accounts for 7.83% of the total number of papers of the ecological footprint.The quantity of the papers is very poor and the number of the results of original research is very small.In the process of quantitative analysis of the land carrying capacity in Wushan County,the paper referred to the results of previous studies,and used ecological footprint model to analyze the land carrying capacity in Wushan County from 2005 to 2010,to provide a basis and reference for the ecological building and sustainable development in Wushan County.In this paper,the land of ecological carrying capacity of Wushan County from 2005 to 2010 was analyzed by using the principles and models of the ecological footprint.According to the principles and models of the ecological footprint,this paper calculated the ecological footprint from 2005 to 2010 in Wushan County,the ecological carrying capacity in 2005 and 2010 in Wushan County,and the ecological footprints of production per

  2. Calculating the Carrying Capacity of Flexural Prestressed Concrete Beams with Non-Metallic Reinforcement

    Directory of Open Access Journals (Sweden)

    Mantas Atutis

    2011-04-01

    Full Text Available The article reviews moment resistance design methods of prestressed concrete beams with fibre-reinforced polymer (FRP reinforcement. FRP tendons exhibit linear elastic response to rupture without yielding and thus failure is expected to be brittle. The structural behaviour of beams prestressed with FRP tendons is different from beams with traditional steel reinforcement. Depending on the reinforcement ratio, the flexural behaviour of the beam can be divided into several groups. The numerical results show that depending on the nature of the element failure, moment resistance calculation results are different by using reviewed methods. It was found, that the use of non-metallic reinforcement in prestressed concrete structures is effective: moment capacity is about 5% higher than that of the beams with conventional steel reinforcement.Article in Lithuanian

  3. Peculiarities of carrying capacity evaluations of cylindrical CFST columns with new type casing

    Directory of Open Access Journals (Sweden)

    Sinkovskaya Olena

    2017-01-01

    Full Text Available This paper deals with a cylindrical steel-concrete load-bearing unit. The feature of the unit is a steel mesh casing that is made from the expanded metal mesh. The optimal parameters of the suggested footing are determined taking into account anisotropy, i. e. different strength and rigidity in different directions that coincide and do not coincide with the direction of reinforcement. The optimal cell angle, when a casing deformation brings about maximum compression of a concrete core, is determined. Details for theoretical calculation of the bearing capacity of a cylindrical steel-concrete load-bearing unit are provided taking into consideration a complex three-dimensional structure of the suggested mesh casing. The validity of the calculations is confirmed by comparison them with the results of the Lira software package. The results of the calculations are provided in the form of the table showing the dependence of the adduced thickness of the plate on the longitudinal movement of the strip of the steel mesh casing. The dependencies to determine the adduced thickness of the mesh casing using the graphical method are provided for all the existing types of the mesh using concrete wedges or excluding them.

  4. Field Carrying Capacity Analysis of Agricultural Sector Based Spatial in Nagari Taram, District of Lima Puluh Kota, West Sumatra

    Directory of Open Access Journals (Sweden)

    Ernamaiyanti Ernamaiyanti

    2016-06-01

    Full Text Available Land conversion has changed the field carryng capacity and filed quality. The purpose of this study is to figured out of field wideness Nagari Taram, and to analyze the availability and suitability of agricultural land Nagari Taram. Analysis of Field carrying capacity based on the Regulation of the Minister of Environment No. 17 of 2009, following by Focus Group Discussion (FGD and analytic hierarchy process (AHP. The results, agricultural land based on type of ecosystem in the by area Nagari Taram is 1003.5 hectares consisting rice fields, dry land, ponds and open waters. Availability of agricultural land Nagari Taram is a surplus. stability of Nagari Taram slopes are low, high, less and medium. analysis showing field carrying suitability Nagari Taram is suitable for land agricultural.

  5. Thermal shaft effects on load-carrying capacity of a fully coupled, variable-properties cryogenic journal bearing

    Science.gov (United States)

    Braun, M. J.; Wheeler, R. L., III; Hendricks, R. C.

    1986-01-01

    The purpose of this work was to perform a rather complete analysis for a cryogenic (oxygen) journal bearing. The Reynolds equation required coupling and simultaneous solution with the fluid energy equation. To correctly account for the changes in the fluid viscosity, the fluid energy equation was coupled with the shaft and bearing heat conduction energy equations. The effects of pressure and temperature on the density, viscosity, and load-carrying capacity were further discussed as analysis parameters, with respect to relative eccentricity and the angular velocity. The isothermal fluid case and the adiabatic fluid case represented the limiting boundaries. The discussion was further extrapolated to study the Sommerfeld number dependency on the fluid Nusselt number and its consequence on possible total loss of load-carrying capacity and/or seizure (catastrophic failure).

  6. Simultaneous Optimization of Tooth Flank Form of Involute Helical Gears in Terms of Both Vibration and Load Carrying Capacity

    Science.gov (United States)

    Komori, Masaharu; Kubo, Aizoh; Suzuki, Yoshitomo

    The alignment condition of automotive gears changes considerably during operation due to the deformation of shafts, bearings, and gear box by transmission of load. Under such conditions, the gears are required to satisfy not only reliability in strength and durability under maximum loading conditions, but also low vibrational characteristics under light loading conditions during the cruising of a car. In this report, the characteristics of the optimum tooth flank form of gears in terms of both vibration and load carrying capacity are clarified. The local optimum tooth flank form appears in each excitation valley, where the vibrational excitation is low and the actual contact ratio takes a specific value. The influence of the choice of different local optimum solutions on the vibrational performance of the optimized gears is investigated. The practical design algorithm for the optimum tooth flank form of a gear set in terms of both vibration and load carrying capacity is then proposed and its result is evaluated by field experience.

  7. Load carrying capacity of shear wall t-connections reinforced with high strength wire ropes

    DEFF Research Database (Denmark)

    Jørgensen, Henrik B.; Bryndom, Thor; Larsen, Michael

    2016-01-01

    Traditionally, U-bar loop connections with keyed joints have been used in vertical shear connections between precast concrete wall elements. However, in the recent years, connections with looped high strength wire ropes instead of U-bar loops have proven to be a much more construction......-friendly solution. The wire ropes have no bending stiffness and therefore allow for an easier vertical installation of the wall elements. During the last 10 – 15 years, a number of shear tests on plane wire rope connections have been carried out. However, to the best knowledge of the authors, tests on wire rope...... connections for assembly of precast elements in different planes, such as T- and L-connections, have not yet been published. This paper presents the results of a large test series recently conducted at the University of Southern Denmark to study the shear behaviour of high strength wire rope T...

  8. Load Carrying Capacity of Shear Wall T-Connections Reinforced with High Strength Wire Ropes

    DEFF Research Database (Denmark)

    Jørgensen, Henrik Brøner; Bryndum, Thor; Larsen, Michael

    2017-01-01

    Traditionally, U-bar loop connections with keyed joints have been used in vertical shear connections between precast concrete wall elements. However, in the recent years, connections with looped high strength wire ropes instead of U-bar loops have proven to be a much more construction......-friendly solution. The wire ropes have no bending stiffness and therefore allow for an easier vertical installation of the wall elements. During the last 10 – 15 years, a number of shear tests on plane wire rope connections have been carried out. However, to the best knowledge of the authors, tests on wire rope...... connections for assembly of precast elements in different planes, such as T- and L-connections, have not yet been published. This paper presents the results of a large test series recently conducted at the University of Southern Denmark to study the shear behaviour of high strength wire rope T...

  9. Approximate Solution of Oil Film Load-carrying Capacity of Turbulent Journal Bearing with Couple Stress Flow

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yongfang; WU Peng; GUO Bo; L Yanjun; LIU Fuxi; YU Yingtian

    2015-01-01

    The instability of the rotor dynamic system supported by oil journal bearing is encountered frequently, such as the half-speed whirl of the rotor, which is caused by oil film lubricant with nonlinearity. Currently, more attention is paid to the physical characteristics of oil film due to an oil-lubricated journal bearing being the important supporting component of the bearing-rotor systems and its nonlinear nature. In order to analyze the lubrication characteristics of journal bearings efficiently and save computational efforts, an approximate solution of nonlinear oil film forces of a finite length turbulent journal bearing with couple stress flow is proposed based on Sommerfeld and Ocvirk numbers. Reynolds equation in lubrication of a finite length turbulent journal bearing is solved based on multi-parametric principle. Load-carrying capacity of nonlinear oil film is obtained, and the results obtained by different methods are compared. The validation of the proposed method is verified, meanwhile, the relationships of load-carrying capacity versus eccentricity ratio and width-to-diameter ratio under turbulent and couple stress working conditions are analyzed. The numerical results show that both couple stress flow and eccentricity ratio have obvious influence on oil film pressure distribution, and the proposed method approximates the load-carrying capacity of turbulent journal bearings efficiently with various width-to-diameter ratios. This research proposes an approximate solution of oil film load-carrying capacity of turbulent journal bearings with different width-to-diameter ratios, which are suitable for high eccentricity ratios and heavy loads.

  10. Alveolar gas exchange and tissue oxygenation during incremental treadmill exercise, and their associations with blood O2 carrying capacity

    Directory of Open Access Journals (Sweden)

    Antti-Pekka E. Rissanen

    2012-07-01

    Full Text Available The magnitude and timing of oxygenation responses in highly active leg muscle, less active arm muscle, and cerebral tissue, have not been studied with simultaneous alveolar gas exchange measurement during incremental treadmill exercise. Nor is it known, if blood O2 carrying capacity affects the tissue-specific oxygenation responses. Thus, we investigated alveolar gas exchange and tissue (m. vastus lateralis, m. biceps brachii, cerebral cortex oxygenation during incremental treadmill exercise until volitional fatigue, and their associations with blood O2 carrying capacity in 22 healthy men. Alveolar gas exchange was measured, and near-infrared spectroscopy (NIRS was used to monitor relative concentration changes in oxy- (Δ[O2Hb], deoxy- (Δ[HHb] and total hemoglobin (Δ[tHb], and tissue saturation index (TSI. NIRS inflection points (NIP, reflecting changes in tissue-specific oxygenation, were determined and their coincidence with ventilatory thresholds (anaerobic threshold (AT, respiratory compensation point (RC; V-slope method was examined. Blood O2 carrying capacity (total hemoglobin mass (tHb-mass was determined with the CO-rebreathing method. In all tissues, NIPs coincided with AT, whereas RC was followed by NIPs. High tHb-mass associated with leg muscle deoxygenation at peak exercise (e.g., Δ[HHb] from baseline walking to peak exercise vs. tHb-mass: r = 0.64, p < 0.01, but not with arm muscle- or cerebral deoxygenation. In conclusion, regional tissue oxygenation was characterized by inflection points, and tissue oxygenation in relation to alveolar gas exchange during incremental treadmill exercise resembled previous findings made during incremental cycling. It was also found out, that O2 delivery to less active m. biceps brachii may be limited by an accelerated increase in ventilation at high running intensities. In addition, high capacity for blood O2 carrying was associated with a high level of m. vastus lateralis deoxygenation at peak

  11. Lateral load-carrying capacity analyses of composite shear walls with double steel plates and filled concrete with binding bars

    Institute of Scientific and Technical Information of China (English)

    周德源; 刘凌飞; 朱立猛

    2016-01-01

    A method is developed to predict the lateral load-carrying capacity of composite shear walls with double steel plates and filled concrete with binding bars (SCBs). Nonlinear finite element models of SCBs were established by using the finite element tool, Abaqus. Tie constraints were used to connect the binding bars and the steel plates. Surface-to-surface contact provided by the Abaqus was used to simulate the interaction between the steel plate and the core concrete. The established models could predict the lateral load-carrying capacity of SCBs with a reasonable degree of accuracy. A calculation method was developed by superposition principle to predict the lateral load-carrying capacity of SCBs for the engineering application. The concrete confined by steel plates and binding bars is under multi-axial compression; therefore, its shear strength was calculated by using the Guo-Wang concrete failure criterion. The shear strength of the steel plates of SCBs was calculated by using the von Mises yielding criterion without considering buckling. Results of the developed method are in good agreement with the testing and finite element results.

  12. [Ecological carrying capacity of Chinese shrimp stock enhancement in Laizhou Bay of East China based on Ecopath model].

    Science.gov (United States)

    Lin, Qun; Li, Xian-sen; Li, Zhong-yi; Jin, Xian-shi

    2013-04-01

    Stock enhancement is an important way of fishery resources conservation, which can increase the high quality fishery resources and improve the fish population structure. The study of ecological carrying capacity is the premise for the scientific implementation of stock enhancement. Based on the survey data of the fishery resources and ecological environment in Laizhou Bay from 2009 to 2010, an Ecopath mass-balance model of the Laizhou Bay ecosystem consisted of 26 functional groups was constructed, and applied to analyze the overall characteristics of the ecosystem, the trophic interrelationships, and the keystone species, and to calculate the ecological carrying capacity of Chinese shrimp enhancement. As for the overall characteristics of the ecosystem, the total primary production/total respiration (TPP/TR) was 1. 53, total primary production/total biomass (TPP/B) was 24.54, Finn' s cycling index was lower (0.07), surplus production was higher (434. 41 t km-2 a-1 ), and system connectance index was lower (0. 29), indicating that this ecosystem was at an early development stage. The analysis on the keystone species showed that Chinese shrimp was not a keystone species of this ecosystem. At present, the biomass of Chinese shrimp in the ecosystem was 0. 1143 t km-2, with a greater potential of continued enhancement. It did not exceed the ecological carrying capacity of 2. 9489 t km-2 when the biomass of the Chinese shrimp was increased by 25. 8 times.

  13. The uncertain role of diversity dependence in species diversification and the need to incorporate time-varying carrying capacities.

    Science.gov (United States)

    Marshall, Charles R; Quental, Tiago B

    2016-04-01

    There is no agreement among palaeobiologists or biologists as to whether, or to what extent, there are limits on diversification and species numbers. Here, we posit that part of the disagreement stems from: (i) the lack of explicit criteria for defining the relevant species pools, which may be defined phylogenetically, ecologically or geographically; (ii) assumptions that must be made when extrapolating from population-level logistic growth to macro-evolutionary diversification; and (iii) too much emphasis being placed on fixed carrying capacities, rather than taking into account the opportunities for increased species richness on evolutionary timescales, for example, owing to increased biologically available energy, increased habitat complexity and the ability of many clades to better extract resources from the environment, or to broaden their resource base. Thus, we argue that a more effective way of assessing the evidence for and against the ideas of bound versus unbound diversification is through appropriate definition of the relevant species pools, and through explicit modelling of diversity-dependent diversification with time-varying carrying capacities. Here, we show that time-varying carrying capacities, either increases or decreases, can be accommodated through changing intrinsic diversification rates (diversity-independent effects), or changing the effects of crowding (diversity-dependent effects).

  14. The Importance of Human Capacity Building in Asia-Pacific Economic Cooperation

    Directory of Open Access Journals (Sweden)

    Tereso Simbulan Jr. Tulloa

    2014-12-01

    Full Text Available Although the importance of human capacity building has been cited in the growth of economies, it has not taken a central role in carrying out regional cooperation in Asia Pacific. In addition, human capacity building is associated with the competitiveness of the economies in the Asia Pacific region. Because of these associations, there are regional benefits arising from enhanced human capacity building beyond the usual private returns and social benefits. In addition, narrowing technological gap through human capacity building can promote greater regional trade. Lastly, regional efforts on human capacity building should not be perceived as a prelude to labor mobility but instead as a prerequisite for greater mobility of capital. Thus, aside from the role of human capacity building in economic growth and competitiveness, it is also crucial in regional connectivity and related with trade liberalization which are major thrusts of APEC.

  15. Conservation endocrinology: A noninvasive tool to understand relationships between carnivore colonization and ecological carrying capacity

    Science.gov (United States)

    Berger, J.; Testa, J.W.; Roffe, T.; Monfort, S.L.

    1999-01-01

    Reproductive technology, especially the diagnosis of pregnancy by radioimmunoassay of fecal steroid metabolites, is an important component of captive propagation, but its role in our understanding of ecological interactions and in situ biological restoration has been more limited. Where large herbivores have been 'released' from predation by the extirpation of carnivores, controversy often exists about possible detrimental effects at the ecosystem level A related concern is that the reestablishment of large carnivores may decrease the availability of prey populations for human subsistence. We suggest that pregnancy assays can be a valuable tool to help distinguish between the roles of predation versus food-imposed limitations on population size and their effects on juvenile recruitment in wild species. We explored this issue through analyses of fecal progestagen concentration (FPC) levels to document pregnancy in moose (Alces alces) in the southern Greater Yellowstone Ecosystem, a site where wolves (Canis lupus) and grizzly bears (Ursus arctos) are recolonizing former habitats after an absence of more than 60 years. Pregnancy was clearly discernible (mean FPC for pregnant and nonpregnant females, respectively: 10.60 vs. 2.57 ??g/g; p rates among the highest in North America. Pregnancy rates, however, dropped from 90% in 1966 to about 75% today, rendering them in the lowest fifteenth percentile among moose populations in North America. Our findings suggest that a relatively low frequency of juvenile moose is not the likely result of predation, and they illustrate how endocrinology can be applied to issues involving reproductive events within an ecological context. They also affirm that noninvasive and generally inexpensive endocrinological procedures will be applicable to understanding interactions between recolonizing predators and prey, an issue that will continue to arise because of global restoration efforts, and to the study of rare ungulates in remote systems

  16. Study on tourist carrying capacity of sustainable tourism---by taking Qingliang Mountain in the south-eastern china as an example

    Science.gov (United States)

    Jin, Shenglang; Liu, Ting

    2017-05-01

    This paper analyzed measurable problems of tourist carrying capacity and then studied the corresponding measures by adopting theories and methods of environment sciences. Tourist carrying capacity of Qingliang Mountain was studied by analyzing the system of tourism environment capacity. The results showed that the level of service was 9726, which was smaller than the ecological carrying capacity of 12894. The facilities and spatial capacity were identified as key factors to limit the tourist carrying capacity in Qingliang Mountain. Some advices and measures including newly built and rebuilt basic facilities, construction of management methods for slack and peak tourist season respectively, construction of new sight spot and touring path were discussed to improve the tourist carrying capacity of Qingliang Mountain and solve the problems of overloading of tourists in the peak season.

  17. Dynamic Changes of Land Ecological Carrying Capacity Based on the Ecological Footprint——By the Case Study of Chengdu City

    Institute of Scientific and Technical Information of China (English)

    Wenfu PENG; Xiaolan ZHONG; Qiuyang LI; Qin LI

    2012-01-01

    Chengdu City is in the period of rapid urbanization and industrialization, and the disturbance derived from human activities on environment is increasing remarkablely in recent 20 years. The pressure on environment, economy and population is also increasing and land use in Chengdu has changed enormously. As struc- ture and function of land ecological system change obviously, sustainable development of land productivity has been an important goal and strategic task from now on, and it is necessary to systematically research land ecological carrying capacity based on ecological footprint. The ecological footprint of Chengdu City in the past ten years was calculated and analyzed from the spatial and temporal aspects according to statistical data from 1998 to 2008, as per ecological footprint method, ecological carrying capacity and the GIS spatial analysis method, and regression analysis method. The ecological footprint and ecological carrying capacity values from 2009 to 2019 in Chengdu City were predicted through calculation results in the past ten years. The results show that the ecological footprint and ecological deficit of land use from 1998 to 2008 increased in Chengdu City. The ecological deficit of land use within the city center was in high levels in the past ten years, and the ecological footprint kept raising, especially in areas, such as Shuangliu, Chongzhou, Qingyang among 9 city areas, 4 counties and 6 districts in Chengdu City. There is fanlike distribution of ecological deficit of land use. Analysis shows that the social and natural ecological system is uneven distribution, which is not in sustainable de- velopment situation. The results of the study show that the economic, social and natural ecological system in Chengdu City is not sustainable, and the ecological foot- print is uneven distribution. The analysis of the dynamic change of land ecological carrying capacity in Chengdu City is very important for city government in the pro- cess of the

  18. Isotopic investigation of contemporary and historic changes in penguin trophic niches and carrying capacity of the southern Indian ocean.

    Science.gov (United States)

    Jaeger, Audrey; Cherel, Yves

    2011-02-02

    A temperature-defined regime shift occurred in the 1970s in the southern Indian Ocean, with simultaneous severe decreases in many predator populations. We tested a possible biological link between the regime shift and predator declines by measuring historic and contemporary feather isotopic signatures of seven penguin species with contrasted foraging strategies and inhabiting a large latitudinal range. We first showed that contemporary penguin isotopic variations and chlorophyll a concentration were positively correlated, suggesting the usefulness of predator δ¹³C values to track temporal changes in the ecosystem carrying capacity and its associated coupling to consumers. Having controlled for the Suess effect and for increase CO₂ in seawater, δ¹³C values of Antarctic penguins and of king penguins did not change over time, while δ¹³C of other subantarctic and subtropical species were lower in the 1970s. The data therefore suggest a decrease in ecosystem carrying capacity of the southern Indian Ocean during the temperature regime-shift in subtropical and subantarctic waters but not in the vicinity of the Polar Front and in southward high-Antarctic waters. The resulting lower secondary productivity could be the main driving force explaining the decline of subtropical and subantarctic (but not Antarctic) penguins that occurred in the 1970s. Feather δ¹⁵N values did not show a consistent temporal trend among species, suggesting no major change in penguins' diet. This study highlights the usefulness of developing long-term tissue sampling and data bases on isotopic signature of key marine organisms to track potential changes in their isotopic niches and in the carrying capacity of the environment.

  19. Isotopic investigation of contemporary and historic changes in penguin trophic niches and carrying capacity of the southern Indian ocean.

    Directory of Open Access Journals (Sweden)

    Audrey Jaeger

    Full Text Available A temperature-defined regime shift occurred in the 1970s in the southern Indian Ocean, with simultaneous severe decreases in many predator populations. We tested a possible biological link between the regime shift and predator declines by measuring historic and contemporary feather isotopic signatures of seven penguin species with contrasted foraging strategies and inhabiting a large latitudinal range. We first showed that contemporary penguin isotopic variations and chlorophyll a concentration were positively correlated, suggesting the usefulness of predator δ¹³C values to track temporal changes in the ecosystem carrying capacity and its associated coupling to consumers. Having controlled for the Suess effect and for increase CO₂ in seawater, δ¹³C values of Antarctic penguins and of king penguins did not change over time, while δ¹³C of other subantarctic and subtropical species were lower in the 1970s. The data therefore suggest a decrease in ecosystem carrying capacity of the southern Indian Ocean during the temperature regime-shift in subtropical and subantarctic waters but not in the vicinity of the Polar Front and in southward high-Antarctic waters. The resulting lower secondary productivity could be the main driving force explaining the decline of subtropical and subantarctic (but not Antarctic penguins that occurred in the 1970s. Feather δ¹⁵N values did not show a consistent temporal trend among species, suggesting no major change in penguins' diet. This study highlights the usefulness of developing long-term tissue sampling and data bases on isotopic signature of key marine organisms to track potential changes in their isotopic niches and in the carrying capacity of the environment.

  20. [Assessment of ecosystem energy flow and carrying capacity of swimming crab enhancement in the Yellow River estuary and adjacent waters].

    Science.gov (United States)

    Lin Qun; Wang, Jun; Li, Zhong-yi; Wu, Qiang

    2015-11-01

    Stock enhancement is increasingly proved to be an important measure of the fishery resources conservation, and the assessment of carrying capacity is the decisive factor of the effects of stock enhancement. Meanwhile, the variations in the energy flow patterns of releasing species and ecosystem were the basis for assessing carrying capacity of stock enhancement. So, in the present study, based on the survey data collected from the Yellow River estuary and adjacent waters during 2012-2013, three Ecopath mass-balance models were established in June, August and October, and the variations in ecosystem energy flow in these months were analyzed, as well as the assessment of carrying capacity of swimming crab enhancement. The energy flow mainly concentrated on trophic level I-III in Yellow River estuary and adjacent waters, and was relatively less on trophic level IV or above. The system flow proportion on the trophic level I was the highest in June, and was the lowest in August. The highest system flow proportion on the trophic level II was found in August, and the lowest in June. The relative and absolute energy flow of swimming crab mainly concentrated on the trophic level III, and the mean trophic level of swimming crab among June, August and October were 3.28. Surplus production was relatively higher in Yellow River estuary and adjacent waters, the highest value was found in June, and the lowest value in August. The ratios of total primary production/total respiration (TPP/TR) were 5.49, 2.47 and 3.01 in June, August and October, respectively, and the ratios of total primary production/total biomass (TPP/B) were 47.61, 33.30 and 29.78, respectively. Combined with the low Finn' s cycling index (FCI: 0.03-0.06), these changes indicated that the Yellow River estuary ecosystem was at an early development stage with higher vulnerability. The energy conversion efficiency of system was from 7.3% to 11.5%, the mean trophic levels of the catch were 3.23, 2.97 and 2.82 in

  1. RESEARCH ON THE POPULATION CARRYING CAPACITY OF THE LAND RESOURCES IN THE ECONOMIC AREA OF ZHUJIANG DELTA

    Institute of Scientific and Technical Information of China (English)

    TANG; Hui-jun

    2001-01-01

    [1]Guangdong Province Statistics Bureau, 2000. The Statistic Annual of Agricultural Economy of Guangdong[Z] ) Beijing:Chinese Statistic Press, 39-40, 203-222. (in Chinese)[2]Guangdong Province Construction Committee, 1996. The Planning of Zhujiang Delta Cities[Z]. Beijing: Chinese Architecture Technology Press. (in Chinese)[3]WANG Ying-cai, ZHANG Miao-ling, 1994. Research on the Population Carrying Potentiality of the Land Resource in Jiangsu Province [M]. Beijing: Chinese Agricultural Technology Press. 288-303. (in Chinese)[4]TANG Hui-jun, 1997. Research on the population carrying capacity of the land resources in the economic area of Zhujiang Delta[J]. Journal of Guangdong University of Technology.14(3): 44. (in Chinese)

  2. Effect of Shear Resistance on Flexural Debonding Load-Carrying Capacity of RC Beams Strengthened with Externally Bonded FRP Composites

    Directory of Open Access Journals (Sweden)

    Guibing Li

    2014-05-01

    Full Text Available Debonding failure is the main failure mode in flexurally strengthened reinforced concrete beams by externally bonded or near surface mounted fibre reinforced polymer (FRP composites. It is believed that FRP debonding will be initiated if the shear stress on the concrete-FRP interface reaches the tensile strength of concrete. However, it was found through experimental and analytical studies that the debonding mechanism of FRP composites has the potential of shear failure in combination with debonding failure. Moreover, the shear failure probably influences the debonding failure. Presently, there are very little experimental and analytical studies to investigate the influence of shear resistance of reinforced concrete (RC beam on FRP debonding failure. The current study investigates and analyzes the effect of shear resistance on FRP debonding failure based on test results. The analytical results show that the shear resistance of RC beam has a great effect on flexural debonding load-carrying capacity of FRP-strengthened RC beam. The influence of shear resistance on flexural debonding load-carrying capacity must be fully considered in flexural strengthening design of RC beams.

  3. Effects of design parameters on carrying capacity of a double-row tapered roller slewing bearing used in wind turbine

    Directory of Open Access Journals (Sweden)

    Yunfeng Li

    2016-07-01

    Full Text Available Mechanical model with detailed design parameters of a rotor slewing bearing with the structure type of double-row tapered roller for supporting the rotor of the wind turbine was presented. The internal geometrical relationships of the rotor slewing bearing were established in the Cartesian coordinate system. The elastic contact deformations between each tapered roller and the raceways were expressed through the geometrical transformation. The mechanical model was established using the equilibrium relations in the rotor slewing bearing. The safety factor and the fatigue life which represents, respectively, the ability of resisting the rolling contact plastic deformation failure and the rolling contact fatigue failure of the rotor slewing bearing were obtained based on the solution of the mechanical model. Effects of the detailed design parameters such as axial clearance, contact angle, and roller semi-cone angle on the carrying capacity of the rotor slewing bearing were analyzed. The results show that right amount of small negative axial clearance, increase in contact angle, and decrease in roller semi-cone angle are advantageous for enhancing the carrying capacity of the rotor slewing bearing. This provides the basis for the reasonable value selection of the design parameters of the double-row tapered roller slewing bearing for supporting the rotor of the wind turbine.

  4. Evaluation of resources and environment carrying capacity and socio-economic pressure in typical ecological regions, China

    Science.gov (United States)

    Qiusen, Huang; Xinyi, Xu

    2017-04-01

    Since the reform and opening up, the socio-economic pressures have led to increasingly tight resource constraints and serious environmental pollution problems in China, especially for typical ecological regions. The ecological system is under a severe situation and resource and environmental issues have become the bottleneck of economic development. Taking the Chen Barag Banner which has been considered as typical ecological regions as an example, the evaluation indexes system of resources and environment carrying capacity was divided into three subsystems: natural driving force, socio-economic pressure and ecological health. On the basis of the indexes system and related data of Chen Barag Banner in 2014, the evaluation model of resources and environment carrying capacity based on spring model were proposed to analysis the state of resources and environment carrying, and an assessment of influence of socio-economic pressure on the resources and environment system has been conducted by using the discretization method of socio-economic data. The results showed that:(1) The resources and environment system of Baorixile Town, Huhenuoer Town and Bayankuren Town were overloaded among the ten towns, the values of Resources and Environment Carrying Capacity(RECC) / Resources and Environment Carrying State(RECS) were 9.86, 1.37 and 1.22, respectively;(2) The natural driving force index of Xiwuzhuer Town, Hadatu state-owned farm and Bayanhada Town were 0.40, 0.42 and 0.43, respectively, which were lower than others and indicated that the natural conditions in these areas were better than others;(3) The situation of ecological environment Ewenke Town, Hadatu state-owned farm and Tenihe state-owned farm were the best due to the result that the ecological health index of these three towns were 0.21, 0.22 and 0.26, respectively, which were lower than others;(4) The influence of socio-economic pressure on the system of resources and environment in Baorixile Town, Hadatu state

  5. Competitive capacity of HIV-1 strains carrying M184I or Y181I drug-resistant mutations

    Institute of Scientific and Technical Information of China (English)

    LI Jue; LI Lin; LI Han-ping; ZHUANG Dao-min; LIU Si-yang; LIU Yong-jian; BAO Zuo-yi; WANG Zheng; LI Jing-yun

    2009-01-01

    Background Virus with nucleoside reverse transcriptase inhibitors (NRTIs) or nonnucleoside reverse transcdptase inhibitors (NNRTIs) resistant mutations show different evolution tendencies when the anti-viral therapies are interrupted. Understanding the replication fitness of drug-resistant virus is important for the study of the prevalence of drug-resistance. For this purpose, we characterized the replication capacity of HIV-1 virus carrying lamivudine (3TC) or nevirapine (NVP) resistant mutations.Methods 3TC and NVP resistant variants were induced in vitro by selecting wild type virus in the presence of drugs. For the competitive replication assay, drug-resistant variants were cocultured with wild-type virus in the presence or absence of drugs. The ratios of the viral species were determined over time by using a real-time RT-PCR-based assay. Results 3TC-resistant (M184I mutation) and NVP-resistant (Y181I mutation) virus should be selected in vitro in two different ways. The competitive replication assay showed that the ratio of virus carrying a M184I mutation increased from 98.8%, while the wild type virus decreased to 1.2% after 4 passages in the presence of 3TC; the percentage of virus carrying the Y181I mutation increased to 90.5%, while wild type virus decreased to 9.5% in the presence of NVP. In the absence of drugs, the ratio of virus carrying the M184I mutation decreased to 5.3%, while wild type virus increased to 94.7%; the ratio of virus carrying Y181I increased to 75%, while wild type virus decreased to 25% after 4 passages.Conclusions The NVP-resistant virus is fitter than wild type virus even in the absence of NVP that may be the reason that NNRTIs-resistant virus is spreading quickly.

  6. Emergy measures of carrying capacity and sustainability of a target region for an ecological restoration programme: a case study in Loess Hilly Region, China.

    Science.gov (United States)

    Dang, Xiaohu; Liu, Guobin

    2012-07-15

    Evaluating the sustainability of a target region for an ecological restoration programme is challenging because it involves different aspects of human society and environment as well as multiple disciplines. Carrying capacity provides a useful measure of the sustainability of a given region where an ecological restoration programme is implemented. In this article, the Yangou catchment, a geomorphic unit, was used as a case study in the Loess Hilly Region of China, where emergy synthesis was used to measure the environmental resources base. The specific standard of living in terms of emergy was employed to calculate carrying capacity over the period 1998-2005 and to assess the sustainability of the Yangou catchment where an ecological restoration programme was carried out. The results of the evaluation indicated that after implementing the ecological restoration programme, there was some improvement in the environmental aspects of the Yangou catchment during the study period, suggesting that the ecological restoration programme alleviated ecological degradation. However, several emergy-based indices and the support areas also illustrated that the ecological restoration programme was not successful enough in terms of preservation and utilisation of environmental resources to enhance sustainability. This indicates that further actions are necessary on conserving environmental resources, improving the emergy input structure for agricultural production and in lifestyle changes for the local people in living in the Yangou catchment.

  7. Yeast NDI1 Improve Oxidative Phosphorylation Capacity and Increases Protection Against Oxidative Stress and Cell Death in Cells Carrying a Leber’s Hereditary Optic Neuropathy Mutation

    Science.gov (United States)

    Park, Jeong Soon; Li, You-fen; Bai, Yidong

    2007-01-01

    G11778A in the subunit ND4 gene of NADH dehydrogenase complex is the most common primary mutation found in Leber’s hereditary optic neuropathy (LHON) patients. The NDI1 gene, which encodes the internal NADH -quinone oxidoreductase in Saccharomyces cerevisiae, was introduced into the nuclear genome of a mitochondrial defective human cell line, Le1.3.1, carrying the G11778A mutation. In transformant cell lines, LeNDI1-1 and -2, total and complex I-dependent respiration were fully restored and largely resistant to complex I inhibitor, rotenone, indicating a dominant role of NDI1 in the transfer of electrons in the host cells. Whereas the original mutant Le1.3.1 cell grows poorly in medium containing galactose, the transformants have a fully restored growth capacity in galactose medium, although the ATP production was not totally recovered. Furthermore, the increased oxidative stress in the cells carrying the G11778A mutation was alleviated in transformants, demonstrated by a decreased reactive oxygen species (ROS) level. Finally, transformants were also shown to be desensitized to induction to apoptosis and also exhibit greater resistance to paraquat-induced cell death. It is concluded that the yeast ND11 enzyme can improve the oxidative phosphorylation capacity in cells carrying the G11778A mutation and protect the cells from oxidative stress and cell death. PMID:17320357

  8. Yeast NDI1 improves oxidative phosphorylation capacity and increases protection against oxidative stress and cell death in cells carrying a Leber's hereditary optic neuropathy mutation.

    Science.gov (United States)

    Park, Jeong Soon; Li, You-Fen; Bai, Yidong

    2007-05-01

    G11778A in the subunit ND4 gene of NADH dehydrogenase complex is the most common primary mutation found in Leber's hereditary optic neuropathy (LHON) patients. The NDI1 gene, which encodes the internal NADH-quinone oxidoreductase in Saccharomyces cerevisiae, was introduced into the nuclear genome of a mitochondrial defective human cell line, Le1.3.1, carrying the G11778A mutation. In transformant cell lines, LeNDI1-1 and -2, total and complex I-dependent respiration were fully restored and largely resistant to complex I inhibitor, rotenone, indicating a dominant role of NDI1 in the transfer of electrons in the host cells. Whereas the original mutant Le1.3.1 cell grows poorly in medium containing galactose, the transformants have a fully restored growth capacity in galactose medium, although the ATP production was not totally recovered. Furthermore, the increased oxidative stress in the cells carrying the G11778A mutation was alleviated in transformants, demonstrated by a decreased reactive oxygen species (ROS) level. Finally, transformants were also shown to be desensitized to induction to apoptosis and also exhibit greater resistance to paraquat-induced cell death. It is concluded that the yeast NDI1 enzyme can improve the oxidative phosphorylation capacity in cells carrying the G11778A mutation and protect the cells from oxidative stress and cell death.

  9. How Social an Animal? The Human Capacity for Caring.

    Science.gov (United States)

    Batson, C. Daniel

    1990-01-01

    Discusses whether humans have a capacity to care about others, or if the target of concern is always oneself. Presents evidence that supports the empathy-altruism hypothesis, suggesting that humans are capable of empathy and caring for another in need. Discusses limits on human capacity for altruistic caring. (JS)

  10. Assessing Potential Habitat and Carrying Capacity for Reintroduction of Plains Bison (Bison bison bison in Banff National Park.

    Directory of Open Access Journals (Sweden)

    Robin Steenweg

    Full Text Available Interest in bison (Bison bison, B. bonasus conservation and restoration continues to grow globally. In Canada, plains bison (B. b. bison are threatened, occupying less than 0.5% of their former range. The largest threat to their recovery is the lack of habitat in which they are considered compatible with current land uses. Fences and direct management make range expansion by most bison impossible. Reintroduction of bison into previously occupied areas that remain suitable, therefore, is critical for bison recovery in North America. Banff National Park is recognized as historical range of plains bison and has been identified as a potential site for reintroduction of a wild population. To evaluate habitat quality and assess if there is sufficient habitat for a breeding population, we developed a Habitat Suitability Index (HSI model for the proposed reintroduction and surrounding areas in Banff National Park (Banff. We then synthesize previous studies on habitat relationships, forage availability, bison energetics and snowfall scenarios to estimate nutritional carrying capacity. Considering constraints on nutritional carrying capacity, the most realistic scenario that we evaluated resulted in an estimated maximum bison density of 0.48 bison/km2. This corresponds to sufficient habitat to support at least 600 to 1000 plains bison, which could be one of the largest 10 plains bison populations in North America. Within Banff, there is spatial variation in predicted bison habitat suitability and population size that suggests one potential reintroduction site as the most likely to be successful from a habitat perspective. The successful reintroduction of bison into Banff would represent a significant global step towards conserving this iconic species, and our approach provides a useful template for evaluating potential habitat for other endangered species reintroductions into their former range.

  11. Assessing Potential Habitat and Carrying Capacity for Reintroduction of Plains Bison (Bison bison bison) in Banff National Park.

    Science.gov (United States)

    Steenweg, Robin; Hebblewhite, Mark; Gummer, David; Low, Brian; Hunt, Bill

    2016-01-01

    Interest in bison (Bison bison, B. bonasus) conservation and restoration continues to grow globally. In Canada, plains bison (B. b. bison) are threatened, occupying less than 0.5% of their former range. The largest threat to their recovery is the lack of habitat in which they are considered compatible with current land uses. Fences and direct management make range expansion by most bison impossible. Reintroduction of bison into previously occupied areas that remain suitable, therefore, is critical for bison recovery in North America. Banff National Park is recognized as historical range of plains bison and has been identified as a potential site for reintroduction of a wild population. To evaluate habitat quality and assess if there is sufficient habitat for a breeding population, we developed a Habitat Suitability Index (HSI) model for the proposed reintroduction and surrounding areas in Banff National Park (Banff). We then synthesize previous studies on habitat relationships, forage availability, bison energetics and snowfall scenarios to estimate nutritional carrying capacity. Considering constraints on nutritional carrying capacity, the most realistic scenario that we evaluated resulted in an estimated maximum bison density of 0.48 bison/km2. This corresponds to sufficient habitat to support at least 600 to 1000 plains bison, which could be one of the largest 10 plains bison populations in North America. Within Banff, there is spatial variation in predicted bison habitat suitability and population size that suggests one potential reintroduction site as the most likely to be successful from a habitat perspective. The successful reintroduction of bison into Banff would represent a significant global step towards conserving this iconic species, and our approach provides a useful template for evaluating potential habitat for other endangered species reintroductions into their former range.

  12. Meta-analysis of intrinsic rates of increase and carrying capacity of populations affected by toxic and other stressors.

    Science.gov (United States)

    Hendriks, A Jan; Maas-Diepeveen, Johanna L M; Heugens, Evelyn H W; Van Straalen, Nico M

    2005-09-01

    Most of the thousands of substances and species that are of concern for environmental management will not be investigated empirically at ecologically relevant levels because of financial, practical, and ethical constraints. To allow risk assessment for these less well-known categories, we have developed a mechanistic model with classical equations from toxicology and ecology. The parameters are linked to well-known properties, such as the octanol-water partition ratio K(ow), acute lethal (body) concentrations, and organism size. This allows estimation of intrinsic rates of increase r and carrying capacity K over a wide range of substances and species. The model was calibrated with parameter values (micro +/- 95% confidence interval) obtained in reviews and validated by a meta-analysis with largely independent data from 200 laboratory experiments. For single substances, the 5 to 95% interval of the observations on intrinsic rates of increase overlapped with the range predicted by the model. Model and experiments independently indicated that population growth ceased below 1% of the acute median lethal concentration in about 5% of the cases. Exceptional values and possible explanations were identified. The reduction of the carrying capacity K was nearly proportional to the inhibition of the population growth r. Population-level effects of mixtures as estimated by concentration addition were confirmed by observations in the experiments. The impact of a toxicant and another stressor could generally be described by response multiplication, with the exception of cases with extreme stress. Data sets on population laboratory experiments are biased to metals and crustaceans. This field will benefit from empirical studies on chemicals, conditions, and species, identified as risky by the model. Other implications of the model for environmental management and research are discussed.

  13. Browsing preference and ecological carrying capacity of sambar deer (Cervus unicolor brookei) on secondary vegetation in forest plantation.

    Science.gov (United States)

    Ismail, Dahlan; Jiwan, Dawend

    2015-02-01

    The browsing preference and ecological carrying capacity (ECC) of sambar deer (Cervus unicolor brookei) in acacia plantations for management and conservation of the ecosystem were investigated at Sabal Forest Reserve in Sarawak, Malaysia. The identification of the species browsed by the sambar deer was based on an observation of the plant parts consumed. ECC estimation was based on body weight (BW) and the physiological stages of animals browsed in six fenced 4-ha paddocks. Sambar deer were found foraging on only 29 out of 42 species of secondary vegetation in the acacia plantation. The remaining species are too high for the deer to reach. Planted species, Shorea macrophylla are not palatable to the deer. This augurs well for the integration of sambar deer into shorea plantations. The most frequently exploited plants were Ficus spp. Sambar deer preferred woody species more than non-woody species and they are browser animals. By producing metabolizable energy of 19,000 to 27,000 MJ/ha, the ECC was five head/ha to 5.25 head/ha. Given its contribution to the conservation of wildlife and its capacity to sustain the ecosystem, the sambar deer integrated farming system offers a promising strategy for the future of tropical forestry management.

  14. A new numerical method for determining collapse load-carrying capacity of structure made of elasto-plastic material

    Institute of Scientific and Technical Information of China (English)

    钟志鹏; 任大龙; 万水

    2014-01-01

    Determination of collapse load-carrying capacity of elasto-plastic material is very important in designing structure. The problem is commonly solved by elasto-plastic finite element method (FEM). In order to deal with material nonlinear problem involving strain softening problem effectively, a new numerical method-damped Newton method was proposed. The iterative schemes are discussed in detail for pure equilibrium models. In the equilibrium model, the plasticity criterion and the compatibility of the strains are verified, and the strain increment and plastic factor are treated as independent unknowns. To avoid the stiffness matrix being singularity or condition of matrix being ill, a damping factor α was introduced to adjust the value of plastic consistent parameter automatically during the iterations. According to the algorithm, the nonlinear finite element program was complied and its numerical example was calculated. The numerical results indicate that this method converges very fast for both small load steps and large load steps. Compared with those results obtained by analysis and experiment, the predicted ultimate bearing capacity from the proposed method is identical.

  15. Resource and Environment Carrying Capacity and Sustainable Development%资源环境承载力与区域可持续发展

    Institute of Scientific and Technical Information of China (English)

    廖慧璇; 籍永丽; 彭少麟

    2016-01-01

    实施“可持续发展战略”是世界各国的发展共识。可持续发展理念的核心是经济发展、资源保护和生态环境保护相协调统一。资源环境承载力是制定可持续发展战略规划的基础。只有准确衡量区域的资源环境承载力,才能从整体上以承载力为约束对国土空间进行科学规划,引导社会经济活动在资源节约、环境保护的基础上科学发展,从而实现区域的可持续发展。文章综述了与区域可持续发展密切相关的四大类资源承载力(包括土地资源、水资源、能源资源和生物资源承载力)和两大类环境承载力(包括空气环境和水环境承载力)的重要性。在综合我国国家标准文件和研究论文的基础上,总结了四大类资源承载力和两大类环境承载力的主要评价指标和评价标准。更进一步,结合我国的资源承载力和可持续发展的研究和实践现状,从研究内容和指标体系构建两方面着眼,指出应尽快制定符合我国国情的评价标准和综合评价体系,并通过简化评价过程来提高资源环境承载力评价的可操作性。%More and more countries have implemented the principle of “sustainable development” into their own development agenda. The key to “sustainable development” is to keep a perfect balance among economic development, resource conservation and environment protection. As the estimations of the magnitudes of the economic development and human population that can be supported by the resource and environment in an area, resource and environment carrying capacities is the foundation of any actions implementing “sustainable development”. Only with the accurate measurements on the resource and environment carrying capacities, will we be able to device developmental plans that take into account of the limiting resources or the worsening environmental conditions, so that “sustainable development” can

  16. Grid Integration and the Carrying Capacity of the U.S. Grid to Incorporate Variable Renewable Energy

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, Jaquelin [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Denholm, Paul [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Speer, Bethany [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Miller, Mackay [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-04-23

    In the United States and elsewhere, renewable energy (RE) generation supplies an increasingly large percentage of annual demand, including nine U.S. states where wind comprised over 10% of in-state generation in 2013. This white paper summarizes the challenges to integrating increasing amounts of variable RE, identifies emerging practices in power system planning and operation that can facilitate grid integration, and proposes a unifying concept—economic carrying capacity—that can provide a framework for evaluating actions to accommodate higher penetrations of RE. There is growing recognition that while technical challenges to variable RE integration are real, they can generally be addressed via a variety of solutions that vary in implementation cost. As a result, limits to RE penetration are primarily economic, driven by factors that include transmission and the flexibility of the power grid to balance supply and demand. This limit can be expressed as economic carrying capacity, or the point at which variable RE is no longer economically competitive or desirable to the system or society.

  17. Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists' Spatial Behavior Simulator Based on GIS and Multi-Agent System

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ren-jun

    2005-01-01

    Based on the study of visitors' individual spatial behaviors, a tourists' spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed, TSBS employs GIS (Geographic Information System) to manage the spatial data, and Multi-Agent system to simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such as location, cost, and state can be analyzed and predicted. Based on this analysis and prediction, the model of assessing the carrying capacity of resorts is built. Our results show that TSBS will be an effective tool to accurately assess the carrying capacity of tourist resorts.

  18. EFFECT OF GROWTH STAGES AND RANGE SYSTEMS ON VEGETATION ATTRIBUTES, CARRYING CAPACITY, STOCKING RATE AND FORAGE PRODUCTIVITY, NORTH KORDOFAN, SUDAN

    Directory of Open Access Journals (Sweden)

    Abdel Moniem M.A. El hag

    2012-03-01

    Full Text Available The range vegetation attributes, carrying capacity, stocking rates and forage productivity were studied in close and open range systems at the flowering and seed setting stages during the September and November 2010, respectively, in El Rosa (El-khuwei locality. Sampling was done by locating 2Km2 in close and open range systems in a radiating manner from the centre of each site. Completely Randomized Design (CRD was used to analyses treatments. Biomass production of plants and plant cover at the flowering stage in the close range system were significantly (P<0.0001 higher than that at the seed setting stage in the open range system. The plant density was significant (P<0.05 higher in the close rang system at the flowering stage and lower at the seed setting stage in the open range system. Bare soil and litter was significantly higher (P<0.0001 in the open range system during the seed setting stage and lower in the close range system during the flowering stage. Forage productivity of plants and shrubs browse kg/ha on rangeland was significantly higher (P<0.05 in the close range system during the flowering stage and lower in open range system at the seed setting stage. Carrying capacity was significantly higher (P<0.0001 in the close range system at the seed setting stage and lower in the open range at the flowering stage. Stoking rates in open range system during the seed setting stage was significantly higher (P<0.0001 and lower in the close range system during the seed setting stage. The frequencies of Huskneet (Cenchrus biflorus, Bano, (Eragrostis tremula, Difra (Echinocloa colonum, leflef Luffa aegyptiaca, Gaw (Aristida sp, Shuleny Zornia glochidiata and Aborakhus Andropogon gayanus were higher in close system during the two stages of growth. Plants such as Abodaib Ceraotheca sesamoid, Bigual Blepharis linarifolia, Tmrfar (Oldenlandia senegalensis, Rabaa (Zalea sp, Himeira Hymerocardia, Diresa (Tribulus terrestris and Huntot Merremia pinnata

  19. 基于物元分析理论的旅游承载力研究%Study on Tourist Carrying Capacity Based on Matter Element Analysis

    Institute of Scientific and Technical Information of China (English)

    刘云国

    2005-01-01

    This paper proposes that it is necessary to implement the concept of tourist carrying capacity to facilitate the tourism planning, and presents a method to evaluate the carrying capacity. The method cailed matter element analysis can solve the uncertain a,nd incompatible problem of the evaluated factors in assessing carrying capacity.The current state of a destination s carrying capacity can be determined by establishing the standard indexes and the matter element model. Through the evaluating of the travel industry zones of the Autonomous Prefecture of Western Hunan, the method is proved to be simple and feasible, and it is improved to be significant for the tourism planning and determination as well as the sustainable development of the regional tourism.

  20. 桑沟湾养殖容量与优化措施的研究%Carrying capacity and optimizing measures for mariculture in Sungo Bay

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The carrying capacity of Sungo Bay for the culture of scallop Chlamys farreri was estimated by calculating the supply and demand of organic carbon produced by primary production.The carrying capacity for the large scallops (5~6 cm shell height) is about 35 ind./m2,which is 15 ind./m2 lower than the actual cultivating density.By calculating the total supply and demand of inorganic nutrient,the carrying capacity of the bay for kelp Laminaria japanica was estimated for the first time in the world.Based on the results from assessment of carrying capacity,some optimizing measures such as polyculture of bivalves and kelp,controlling fouling organisms,adjusting the size of longline block,enlarging the navigation channel and so on were proposed and practiced in the bay.

  1. Hypoxia effects on gill surface area and blood oxygen-carrying capacity of the Atlantic stingray, Dasyatis sabina.

    Science.gov (United States)

    Dabruzzi, Theresa F; Bennett, Wayne A

    2014-08-01

    Atlantic stingrays, Dasyatis sabina, are common residents of shallow-water seagrass habitats that experience natural cycles of severe hypoxia during summer months. We hypothesized that stingrays exposed to hypoxic episodes would improve their hypoxia tolerance by increasing branchial surface area and altering blood oxygen-carrying capacity. To this end, we compared critical oxygen minimum, gill morphology, and hemoglobin/hematocrit levels in a control group of Atlantic stingrays held at continuous oxygen saturations of 80-90% (≥5.5 mg/l), to treatment groups exposed to a 7-h hypoxic interval at 55% (~4.0 mg/l), or 30% oxygen saturation (~2.0 mg/l). Stingrays in hypoxic treatment groups significantly improved their hypoxia tolerance. Critical oxygen minimum values fell from 0.7 ± 0.11 mg/l in control fish to 0.4 ± 0.05 and 0.4 ± 0.06 mg/l in the 55 and 30% saturation treatment groups, respectively. Mass-specific gill surface area between control fish and the 30% saturation treatment group increased by 1.7-fold, from 85 to 142 mm(2)/g. Although stingrays did not show an increase in hematocrit or hemoglobin levels, production of more efficient hemoglobin isoforms could not be ruled out. An increase in hypoxia tolerance allows Atlantic stingrays to forage for longer times and across a wide range of hypoxic habitats that are less accessible to predators and competitors.

  2. Climate change is projected to reduce carrying capacity and redistribute species richness in North Pacific pelagic marine ecosystems.

    Science.gov (United States)

    Woodworth-Jefcoats, Phoebe A; Polovina, Jeffrey J; Drazen, Jeffrey C

    2017-03-01

    Climate change is expected to impact all aspects of marine ecosystems, including fisheries. Here, we use output from a suite of 11 earth system models to examine projected changes in two ecosystem-defining variables: temperature and food availability. In particular, we examine projected changes in epipelagic temperature and, as a proxy for food availability, zooplankton density. We find that under RCP8.5, a high business-as-usual greenhouse gas scenario, increasing temperatures may alter the spatial distribution of tuna and billfish species richness across the North Pacific basin. Furthermore, warmer waters and declining zooplankton densities may act together to lower carrying capacity for commercially valuable fish by 2-5% per decade over the 21st century. These changes have the potential to significantly impact the magnitude, composition, and distribution of commercial fish catch across the pelagic North Pacific. Such changes will in turn ultimately impact commercial fisheries' economic value. Fishery managers should anticipate these climate impacts to ensure sustainable fishery yields and livelihoods.

  3. Carbon carry capacity and carbon sequestration potential in China based on an integrated analysis of mature forest biomass.

    Science.gov (United States)

    Liu, YingChun; Yu, GuiRui; Wang, QiuFeng; Zhang, YangJian; Xu, ZeHong

    2014-12-01

    Forests play an important role in acting as a carbon sink of terrestrial ecosystem. Although global forests have huge carbon carrying capacity (CCC) and carbon sequestration potential (CSP), there were few quantification reports on Chinese forests. We collected and compiled a forest biomass dataset of China, a total of 5841 sites, based on forest inventory and literature search results. From the dataset we extracted 338 sites with forests aged over 80 years, a threshold for defining mature forest, to establish the mature forest biomass dataset. After analyzing the spatial pattern of the carbon density of Chinese mature forests and its controlling factors, we used carbon density of mature forests as the reference level, and conservatively estimated the CCC of the forests in China by interpolation methods of Regression Kriging, Inverse Distance Weighted and Partial Thin Plate Smoothing Spline. Combining with the sixth National Forest Resources Inventory, we also estimated the forest CSP. The results revealed positive relationships between carbon density of mature forests and temperature, precipitation and stand age, and the horizontal and elevational patterns of carbon density of mature forests can be well predicted by temperature and precipitation. The total CCC and CSP of the existing forests are 19.87 and 13.86 Pg C, respectively. Subtropical forests would have more CCC and CSP than other biomes. Consequently, relying on forests to uptake carbon by decreasing disturbance on forests would be an alternative approach for mitigating greenhouse gas concentration effects besides afforestation and reforestation.

  4. A New Methodology for Solving Trajectory Planning and Dynamic Load-Carrying Capacity of a Robot Manipulator

    Directory of Open Access Journals (Sweden)

    Wanjin Guo

    2016-01-01

    Full Text Available A new methodology using a direct method for obtaining the best found trajectory planning and maximum dynamic load-carrying capacity (DLCC is presented for a 5-degree of freedom (DOF hybrid robot manipulator. A nonlinear constrained multiobjective optimization problem is formulated with four objective functions, namely, travel time, total energy involved in the motion, joint jerks, and joint acceleration. The vector of decision variables is defined by the sequence of the time-interval lengths associated with each two consecutive via-points on the desired trajectory of the 5-DOF robot generalized coordinates. Then this vector of decision variables is computed in order to minimize the cost function (which is the weighted sum of these four objective functions subject to constraints on joint positions, velocities, acceleration, jerks, forces/torques, and payload mass. Two separate approaches are proposed to deal with the trajectory planning problem and the maximum DLCC calculation for the 5-DOF robot manipulator using an evolutionary optimization technique. The adopted evolutionary algorithm is the elitist nondominated sorting genetic algorithm (NSGA-II. A numerical application is performed for obtaining best found solutions of trajectory planning and maximum DLCC calculation for the 5-DOF hybrid robot manipulator.

  5. Carrying capacity and tourism planning. case study at Praia Brava- Itajai, in face to the settlement of Canto da Brava Resort

    OpenAIRE

    Doris Van de Meene Ruschmann; Luciana Paolucci; Nelson Antonio Leite Maciel

    2008-01-01

    Sustainable tourism presumes cultural authenticity, social inclusion, conservation of natural resources and service quality. Those are major issues standing for economical viability in the long run. This article analyzes carrying capacity in Praia Brava, Itajai/SC, evaluating environmental comfort for dwellers as well as for users of the beach building future scenarios as Canto da Brava resort is settled. Tourism carrying capacity is tied to methods of identification and evaluation of environ...

  6. Superantigen presenting capacity of human astrocytes

    DEFF Research Database (Denmark)

    Hassan-Zahraee, M; Ladiwala, U; Lavoie, P M;

    2000-01-01

    We found that human fetal astrocytes (HFA) are able to support superantigen (SAG) staphylococcal enterotoxin B (SEB) and toxic shock syndrome toxin-1 (TSST-1)-induced activation of immediately ex vivo allogenic human CD4 T cells. Using radiolabelled toxins, we demonstrate that both SEB and TSST-1...

  7. Research on atmospheric environment carrying capacity of ports%港口大气环境承载力研究

    Institute of Scientific and Technical Information of China (English)

    刘长兵

    2012-01-01

    以秦皇岛煤炭港口为例,筛选煤粉尘(TSP)作为典型大宗散货港口大气环境优先污染物,通过对港口区域现有重点煤尘污染源、烟尘污染源和工业粉尘污染源排放和治理状况以及大气污染物迁移扩散规律的研究,结合社会、经济和环境因素,以满足秦皇岛煤炭作业环境和周边地区大气环境功能区环境质量标准为约束条件,探求了港口大气污染物排放总量及环境承载力控制目标.%In this paper,taking Qinhuangdao coal port for example,TSP was selected as the priority pollutants of atmospheric environment of the typical large-sized bulk cargo port.The emission and treatment of the existing key pollution sources for coal dust smoke and dust, industrial dust and the spreading law of air pollutants in port area were studied.Under the constraint conditions of coal working environment of Qinhuangdao and the atmospheric environment functional regionalization environmental quality standard of its surrounding areas,the control targets of the total air pollutants emission and the environment carrying capacity of port were explored with the combination of the social,economic and environmental factors.These results can provide effective technical support for the general development plan of port,dust pollution treatment and environmental feasibility study of a new port.

  8. 楼观台森林公园旅游环境容量研究%Tourism Environmental Carrying Capacity of Louguantai Forest Park

    Institute of Scientific and Technical Information of China (English)

    张晓慧; 陈强

    2011-01-01

    综合旅游空间容量、旅游生态容量、旅游设施容量、旅游心理容量4个因素,对楼观台国家森林公园旅游环境容量进行了测算,通过对比发现楼观台森林公园游客接待量远小于理论旅游环境容量,并对造成这种现状的主要原因进行了分析,提出了相关建议.%In this paper, an integrated estimation on the tourism environmental carrying capacity of Louguantai National Forest Park was made from the aspects of ecological carrying capacity, spatial carrying capacity, facility carrying capacity, and psychological carrying capacity. It was found that the number of reception tourists in the park was far less than its theoretical predication tourism environment capacity. Main reasons were analysised and some suggestions were proposed.

  9. Evaluation of Carrying Capacity : Measure 7.1A of the Northwest Power Planning Council`s 1994 Fish and Wildlife Program : Report 1 of 4, Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Neitzel, Duane A.; Johnson, Gary E.

    1996-05-01

    This report is one of four that the Pacific Northwest National Laboratory (PNNL) staff prepared to address Measure 7.1A in the Northwest Power Planning Council's (Council) Fish and Wildlife Program (Program) dated december 1994 (NPPC 1994). Measure 7.1A calls for the Bonneville Power Administration (BPA) to fund an evaluation of salmon survival, ecology, carrying capacity, and limiting factors in freshwater, estuarine, and marine habitats. Additionally, the Measure asks for development of a study plan based on critical uncertainties and research needs identified during the evaluation. This report deals with the evaluation of carrying capacity. It describes the analysis of different views of capacity as it relates to salmon survival and abundance. The report ends with conclusions and recommendations for studying carrying capacity.

  10. Functional residual capacity: the human windbag.

    Science.gov (United States)

    Villars, Penelope S; Kanusky, Joseph T; Levitzky, Michael G

    2002-10-01

    Like the windbag of a bagpipe, the functional residual capacity (FRC) is the lung volume that acts as a reservoir of air for physiologic use. This reserve volume is particularly important during the period of apnea that occurs during induction of general anesthesia. The balance of the inward elastic recoil of the lung and the outward chest wall forces determines the FRC. Inward recoil forces are dependent on the interaction between the fibrous skeleton of the lung tissue and the alveolar surface tension regulated by pulmonary surfactant. Positioning and the use of inhaled and intravenous anesthetics influence outward chest wall forces. Factors that affect the FRC may be altered by volume recruitment maneuvers such as administration of vital capacity breaths, the application of positive end-expiratory pressure, and/or maintenance of anesthesia with a fraction of inspired oxygen of less than 1.0. This course reviews the basic anatomy and physiology of the FRC during the perioperative period. Understanding the processes that contribute to intraoperative loss of lung volume and knowledge of interventions that can allay them are paramount to providing a reliable and safe general anesthetic.

  11. 青海省玉树州相对资源承载力评价%Evaluation of Relative Carrying Capacity of Resources in Yushu,Qinghai Province

    Institute of Scientific and Technical Information of China (English)

    李明明

    2013-01-01

    By using the improved model of relative carrying capacity of resources,this paper evaluates the spatial-temporal carrying capacity of resources in Yushu area The result shows that the relative carrying capacity of resources was in a surplus state from 1999 to 2008,but the surplus was decreasing.The carrying capacity of land resources is much higher than that of economic resources,and the resources of grassland and woodland have made the greatest contribution to the carrying capacity of synthetic resources.In addition,the carrying capacity of resources in Yushu area is characterized by an obvious spatial distribution,with differences of the carrying capacity between the west-eastern areas and the north-southern areas.%采用修正后的相对资源承载力模型从时间和空间对玉树州资源承载力进行评价,结果表明:1999-2008年间,玉树州相对资源承载力处于富余状态,但富余量在逐渐减小;土地资源承载力远大于经济资源承载力,其中牧草地资源和林地资源对综合资源承载力贡献最大;资源承载力空间分布特征明显,主要表现为东西部和南北部的资源承载力分布差异.

  12. Does recombinant human Epo increase exercise capacity by means other than augmenting oxygen transport?

    DEFF Research Database (Denmark)

    Lundby, C; Robach, P; Boushel, R;

    2008-01-01

    This study was performed to test the hypothesis that administration of recombinant human erythropoietin (rHuEpo) in humans increases maximal oxygen consumption by augmenting the maximal oxygen carrying capacity of blood. Systemic and leg oxygen delivery and oxygen uptake were studied during...... before rHuEpo treatment). Blood buffer capacity remained unaffected by rHuEpo treatment and hemodilution. The augmented hematocrit did not compromise peak cardiac output. In summary, in healthy humans, rHuEpo increases maximal oxygen consumption due to augmented systemic and muscular peak oxygen delivery....

  13. Superantigen presenting capacity of human astrocytes

    DEFF Research Database (Denmark)

    Hassan-Zahraee, M; Ladiwala, U; Lavoie, P M

    2000-01-01

    We found that human fetal astrocytes (HFA) are able to support superantigen (SAG) staphylococcal enterotoxin B (SEB) and toxic shock syndrome toxin-1 (TSST-1)-induced activation of immediately ex vivo allogenic human CD4 T cells. Using radiolabelled toxins, we demonstrate that both SEB and TSST-1...... bind with high affinity to MHC class II antigen expressing astrocytes; binding is displaceable with excess cold toxin. Competition experiments further indicate that TSST-1 and SEB at least partially compete with each other for binding to astrocytes suggesting they bind to the same HLA-DR region...

  14. GIS and agent based spatial-temporal simulation modeling for assessing tourism social carrying capacity: a study on Mount Emei scenic area, China

    Science.gov (United States)

    Zhang, Renjun

    2007-06-01

    Each scenic area can sustain a specific level of acceptance of tourist development and use, beyond which further development can result in socio-cultural deterioration or a decline in the quality of the experience gained by visitors. This specific level is called carrying capacity. Social carrying capacity can be defined as the maximum level of use (in terms of numbers and activities) that can be absorbed by an area without an unacceptable decline in the quality of experience of visitors and without an unacceptable adverse impact on the society of the area. It is difficult to assess the carrying capacity, because the carrying capacity is determined by not only the number of visitors, but also the time, the type of the recreation, the characters of each individual and the physical environment. The objective of this study is to build a spatial-temporal simulation model to simulate the spatial-temporal distribution of tourists. This model is a tourist spatial behaviors simulator (TSBS). Based on TSBS, the changes of each visitor's travel patterns such as location, cost, and other states data are recoded in a state table. By analyzing this table, the intensity of the tourist use in any area can be calculated; the changes of the quality of tourism experience can be quantized and analyzed. So based on this micro simulation method the social carrying capacity can be assessed more accurately, can be monitored proactively and managed adaptively. In this paper, the carrying capacity of Mount Emei scenic area is analyzed as followed: The author selected the intensity of the crowd as the monitoring Indicators. it is regarded that longer waiting time means more crowded. TSBS was used to simulate the spatial-temporal distribution of tourists. the average of waiting time all the visitors is calculated. And then the author assessed the social carrying capacity of Mount Emei scenic area, found the key factors have impacted on social carrying capacity. The results show that the TSBS

  15. Carrying capacity and tourism planning. case study at Praia Brava- Itajai, in face to the settlement of Canto da Brava Resort

    Directory of Open Access Journals (Sweden)

    Doris Van de Meene Ruschmann

    2008-05-01

    Full Text Available Sustainable tourism presumes cultural authenticity, social inclusion, conservation of natural resources and service quality. Those are major issues standing for economical viability in the long run. This article analyzes carrying capacity in Praia Brava, Itajai/SC, evaluating environmental comfort for dwellers as well as for users of the beach building future scenarios as Canto da Brava resort is settled. Tourism carrying capacity is tied to methods of identification and evaluation of environmental indicators. In this case, Cifuentes Method was chosen because it integrates physical, biotical and infra structural factors, through assessment of physical, real and effective carrying capacity. Quantitative results have been considered analyzing impacts and tolerable limits of change taking into account users perception.

  16. 成都市水资源及水环境承载能力分析%Study on water resources and water environmental carrying capacities of Chengdu

    Institute of Scientific and Technical Information of China (English)

    薛小妮; 甘泓; 游进军; 牛存稳

    2012-01-01

    Based on the analyses made on the definitions of the water resources carrying capacity and water environmental carrying capacity and the significances of studies on them, both the carrying capacities of various target years of Chengdu are calculated herein with a three-level methodology and the one-dimension water quality simulation based pollutant-holding capacity model respectively, and then a comparative analysis is made on the calculation results. The result shows that the limitation from water environmental capacity on the water consumption of Chengdu becomes more strict under the current condition, while the water resources carrying capacity is to restrict the socio-economic development gradually in the days to come. Therefore, the sustainable economic and social development can only be ensured therein by taking both the carrying capacities as the control points concerned.%本文在分析水资源和水环境承载能力定义及研究意义的基础上,分别利用三层次分析方法和基于一维水质模拟的纳污能力模型计算了成都市不同水平年的水资源与水环境承载能力,并对计算结果进行对比分析.结果显示现状条件下成都市的水环境承载能力对用水的限制更为严格,而未来水资源承载能力逐渐开始制约社会经济发展.为此,只有以水资源承载能力及水环境承载能力作为控制点,才能保障经济社会的可持续发展.

  17. 人口承载力研究的演进、问题与展望%Research on Population Carrying Capacity: Evolution, Problems and Prospect

    Institute of Scientific and Technical Information of China (English)

    童玉芬

    2012-01-01

    There have long been debates and conflicting arguments in the studies of population cartying capacity. This paper examines dilemmas and challenges in the studies of population carrying capacity. There are three major difficulties in the research of population carrying capacity: difficulty in conducting quantitative models of population carrying capacity with empirical researches due to limitations in theoretical hypotheses, difficulty in accurately determining the results of population carrying capacity due to the changing nature and the complexity and uncertainty of the influencing factors of population carrying capacity, and difficulty in operationalizing policy measures deriving from the research on popu- lation carrying capacity. The author argues that population carrying capacity exists objectively, and scholars should not abandon their research just because of the difficulties and problems in the studies of population carrying capacity. There is a need in the research on population carrying capacity to disembarrass of that of biological carrying capacity. Studies on population carrying capacity need to be conducted in dynamic perspectives.%在人口承载力研究的过程中,始终伴随着对人口承载力的争论、质疑甚至否定。文章分析了人口承载力演变的过程和存在的困境及原因,认为目前的困难主要表现在:由于人口承载力研究理论假设的局限,从而导致了入口承载力的定量模型难以得到实证检验;人口承载力影响因素的动态性、不确定性和多样性,导致承载力结果难以精确测定;受到研究范式的局限,由概念的不精确和歧义导致了可操作性差。最后指出,人口承载力是客观存在的,不能因为人口承载力研究中存在的这些困难而作为放弃人口承载力研究的借口;人口承载力的研究,需要进一步摆脱生物承载力的研究模式,从一种固定不变的环境和不变的生活模式等

  18. Earth Resources Technology Satellite-1 (ERTS-1) data and anthropology: Use of these data in carrying capacity estimates for sites in Upper Volta and Niger

    Science.gov (United States)

    Reining, P. (Principal Investigator)

    1974-01-01

    The author has identified the following significant results. Repetitively derived multispectral band imagery from ERTS-1 is now available for many parts of the earth's land surface and represents major new data sources for anthropological work in habitat, land use, and settlement patterns. A completed first step test of ERTS-1 data is available in carrying capacity estimates for Mossi, Hausa, and Sonrai sites derived from: (1) field work; (2) aerial photography; and (3) ERTS-1. Data can test more than one carrying capacity formula.

  19. Effective carrying capacity and analytical solution of a particular case of the Richards-like two-species population dynamics model

    Science.gov (United States)

    Cabella, Brenno Caetano Troca; Ribeiro, Fabiano; Martinez, Alexandre Souto

    2012-02-01

    We consider a generalized two-species population dynamic model and analytically solve it for the amensalism and commensalism ecological interactions. These two-species models can be simplified to a one-species model with a time dependent extrinsic growth factor. With a one-species model with an effective carrying capacity one is able to retrieve the steady state solutions of the previous one-species model. The equivalence obtained between the effective carrying capacity and the extrinsic growth factor is complete only for a particular case, the Gompertz model. Here we unveil important aspects of sigmoid growth curves, which are relevant to growth processes and population dynamics.

  20. Carry a big stick, or no stick at all An experimental analysis of trust and capacity of punishment

    OpenAIRE

    Vicente Calabuig; Enrique Fatas; Gonzalo Olcina; Ismael Rodriguez-Lara

    2013-01-01

    We investigate the effect of punishment in a trust game with endowment heterogeneity in which the investor may punish the allocator at a cost. Our results indicate that the effect of the punishment crucially depends on the investor’s capacity of punishment, that is measured in our experiment by the proportion of the allocator’s payoffs that the investor can destroy. We find that punishment fosters trust when the capacity of punishment is high (i.e., when the cost of punishing is relatively lo...

  1. Analysis of the University of Ibadan Carrying Capacities vis-à-vis Enrolment and Facilities' Maintenance: Implications on Administration and Curriculum Implementation

    Science.gov (United States)

    Atanda, Ademola

    2013-01-01

    This study investigated the extent to which the University of Ibadan complies with carrying capacity standards as directed by the National Universities Commission (NUC) and the level of facility maintenance. A descriptive research design was adopted with three research questions. The population of study comprised undergraduate students and an…

  2. Potential for Grey wolf Canis lupus in the Netherlands : effects of habitat fragmentation and climate change on the carrying capacity and population dynamics

    NARCIS (Netherlands)

    Potiek, A.; Wamelink, G.W.W.; Jochem, R.; Langevelde, van F.

    2012-01-01

    Recolonization of the Netherlands by wolves is likely to occur within 5 to 10 years, and for management reasons the habitat suitability should be understood. Therefore, I predicted the carrying capacity and population dynamics of the wolf in the Netherlands, and studied the effects of habitat fragme

  3. Habitat carrying capacity is reached for the European eel in a small coastal catchment: evidence and implications for managing eel stocks

    NARCIS (Netherlands)

    Acou, A.; Rivot, E.; van Gils, J.A.; Legault, A.; Ysnel, F.; Feunteun, E.

    2011-01-01

    1. Despite carrying capacity being one of the most important parameters in population management and modelling, we lack substantial evidence for habitat limitations on freshwater species. Here we tested the ideal free distribution (IFD) hypothesis using an indirect behaviour-based method for small c

  4. Analysis of the University of Ibadan Carrying Capacities vis-à-vis Enrolment and Facilities' Maintenance: Implications on Administration and Curriculum Implementation

    Science.gov (United States)

    Atanda, Ademola

    2013-01-01

    This study investigated the extent to which the University of Ibadan complies with carrying capacity standards as directed by the National Universities Commission (NUC) and the level of facility maintenance. A descriptive research design was adopted with three research questions. The population of study comprised undergraduate students and an…

  5. Potential for Grey wolf Canis lupus in the Netherlands : effects of habitat fragmentation and climate change on the carrying capacity and population dynamics

    NARCIS (Netherlands)

    Potiek, A.; Wamelink, G.W.W.; Jochem, R.; Langevelde, van F.

    2012-01-01

    Recolonization of the Netherlands by wolves is likely to occur within 5 to 10 years, and for management reasons the habitat suitability should be understood. Therefore, I predicted the carrying capacity and population dynamics of the wolf in the Netherlands, and studied the effects of habitat

  6. Could the local population of the Lower Rhine delta supply the Roman army? Part 2: Modelling the carrying capacity using archaeological, palaeo-ecological and geomorphological data

    NARCIS (Netherlands)

    M. van Dinter; L.I. Kooistra; M.K. Dütting; P. van Rijn; C. Cavallo

    2014-01-01

    In this part two of a diptych of articles, we modelled and quantified the carrying capacity of the landscape and the demand and supply of the Roman army in the western Lower Rhine delta with wood and food in the period A.D. 40 - 140. The absolute volumes of the wood and food were calculated (in m³ a

  7. Efficient expansion of human keratinocyte stem/progenitor cells carrying a transgene with lentiviral vector

    Science.gov (United States)

    2013-01-01

    Introduction The development of an appropriate procedure for lentiviral gene transduction into keratinocyte stem cells is crucial for stem cell biology and regenerative medicine for genetic disorders of the skin. However, there is little information available on the efficiency of lentiviral transduction into human keratinocyte stem/progenitor cells and the effects of gene transduction procedures on growth potential of the stem cells by systematic assessment. Methods In this study, we explored the conditions for efficient expansion of human keratinocyte stem/progenitor cells carrying a transgene with a lentiviral vector, by using the culture of keratinocytes on a feeder layer of 3 T3 mouse fibroblasts. The gene transduction and expansion of keratinocytes carrying a transgene were analyzed by Western blotting, quantitative PCR, and flow cytometry. Results Polybrene (hexadiamine bromide) markedly enhanced the efficiency of lentiviral gene transduction, but negatively affected the maintenance of the keratinocyte stem/progenitor cells at a concentration higher than 5 μg/ml. Rho-assiciated kinase (ROCK) inhibitor Y-27632, a small molecule which enhanced keratinocyte proliferation, significantly interfered with the lentiviral transduction into cultured human keratinocytes. However, a suitable combination of polybrene and Y-27632 effectively expanded keratinocytes carrying a transgene. Conclusions This study provides information for effective expansion of cultured human keratinocyte stem/progenitor cells carrying a transgene. This point is particularly significant for the application of genetically modified keratinocyte stem/progenitor stem cells in regenerative medicine. PMID:24406242

  8. 区域环境承载力的定量化探讨--以大连市为例%Quantificational Study on Carrying Capacity of the Regional Environment -Taking the City of Dalian as an Example

    Institute of Scientific and Technical Information of China (English)

    狄乾斌

    2005-01-01

    With the analysis of the connotation and charter of the regional environment's carrying capacity, this paper,firstly, establishes the index system on the base of the affecting factors. Secondly, this paper discusses the methods of the quantization of the environment's carrying capacity of Dalian. Finally, this paper predicts the changing tendency of the environment's carrying capacity.

  9. Theory Analysis and Experiment Research of the Leg Mechanism for the Human-Carrying Walking Chair Robot

    Directory of Open Access Journals (Sweden)

    Lingfeng Sang

    2014-01-01

    Full Text Available For the high carrying capacity of the human-carrying walking chair robot, in this paper, 2-UPS+UP parallel mechanism is selected as the leg mechanism; then kinematics, workspace, control, and experiment of the leg mechanism are researched in detail. Firstly, design of the whole mechanism is described and degrees of freedom of the leg mechanism are analyzed. Second, the forward position, inverse position, and velocity of leg mechanism are studied. Third, based on the kinematics analysis and the structural constraints, the reachable workspace of 2-UPS+UP parallel mechanism is solved, and then the optimal motion workspace is searched in the reachable workspace by choosing the condition number as the evaluation index. Fourth, according to the theory analysis of the parallel leg mechanism, its control system is designed and the compound position control strategy is studied. Finally, in optimal motion workspace, the compound position control strategy is verified by using circular track with the radius 100 mm; the experiment results show that the leg mechanism moves smoothly and does not tremble obviously. Theory analysis and experiment research of the single leg mechanism provide a theoretical foundation for the control of the quadruped human-carrying walking chair robot.

  10. Study on Early Warning of Traffic Resources and Environment Carrying Capacity%交通资源环境承载力预警研究

    Institute of Scientific and Technical Information of China (English)

    蒋恵园; 黄永燊

    2015-01-01

    新常态下快速发展的综合交通运输对资源环境的胁迫作用日益明显,资源环境对交通运输的承载能力成为地区健康发展的重要衡量标准。在界定交通资源环境承载力概念的基础上,从资源承载力和生态环境承载力两个方面构建交通资源环境承载力指标体系。结合可拓学的模糊物元理论和信息论的熵理论,建立基于模糊物元的交通资源环境承载力的预警模型,并对长江经济带七省二市的交通资源环境承载力进行预警研究。实例结果表明,构建的交通资源环境承载力指标体系基本合理,模糊物元预警模型在资源环境承载力的预警研究中具有较强的适用性和可操作性。%The rapid development of integrated transportation in the new normal poses an increasing threat to environment and resources. The bearing capacity of environment and resources to transportation becomes a significant criterion to measure whether an area is developing healthily. Based on the definition of traffic resource environmental bearing capacity, a traffic resource and environmental bearing capacity index system is built from both resources carrying capacity and environmental carrying capacity aspects. Through combining fuzzy matter-element theory of extension theory with entropy theory, an early-warning model of traffic resource and environmental bearing capacity is established, this model is applied to study the traffic resources and environmental carrying capacity of Yangtze River economic belt (include seven provinces and two municipalities as well). The results demonstrate that:The traffic resources and environmental carrying capacity index system is reasonable and the fuzzy matter-element model used in studying the early-warning of resources environmental bearing capacity is of sound applicability and operability.

  11. Limited communication capacity unveils strategies for human interaction

    Science.gov (United States)

    Miritello, Giovanna; Lara, Rubén; Cebrian, Manuel; Moro, Esteban

    2013-06-01

    Connectivity is the key process that characterizes the structural and functional properties of social networks. However, the bursty activity of dyadic interactions may hinder the discrimination of inactive ties from large interevent times in active ones. We develop a principled method to detect tie de-activation and apply it to a large longitudinal, cross-sectional communication dataset (~19 months, ~20 million people). Contrary to the perception of ever-growing connectivity, we observe that individuals exhibit a finite communication capacity, which limits the number of ties they can maintain active in time. On average men display higher capacity than women, and this capacity decreases for both genders over their lifespan. Separating communication capacity from activity reveals a diverse range of tie activation strategies, from stable to exploratory. This allows us to draw novel relationships between individual strategies for human interaction and the evolution of social networks at global scale.

  12. Erythropoietin treatment enhances muscle mitochondrial capacity in humans

    DEFF Research Database (Denmark)

    Plenge, Ulla; Belhage, Bo; Guadalupe-Grau, Amelia;

    2012-01-01

    Erythropoietin (Epo) treatment has been shown to induce mitochondrial biogenesis in cardiac muscle along with enhanced mitochondrial capacity in mice. We hypothesized that recombinant human Epo (rhEpo) treatment enhances skeletal muscle mitochondrial oxidative phosphorylation (OXPHOS) capacity...... in humans. In six healthy volunteers rhEpo was administered by sub-cutaneous injection over 8 weeks with oral iron (100 mg) supplementation taken daily. Mitochondrial OXPHOS was quantified by high-resolution respirometry in saponin-permeabilized muscle fibers obtained from biopsies of the vastus lateralis...... before and after rhEpo treatment. OXPHOS was determined with the mitochondrial complex I substrates malate, glutamate, pyruvate, and complex II substrate succinate in the presence of saturating ADP concentrations, while maximal electron transport capacity (ETS) was assessed by addition of an uncoupler...

  13. Assessment of water ecological carrying capacity under the two policies in Tieling City on the basis of the integrated system dynamics model.

    Science.gov (United States)

    Wang, Shuo; Xu, Ling; Yang, Fenglin; Wang, He

    2014-02-15

    Considering the limitation of the traditional method to assess the ecological carrying capacity and the complexity of the water ecological system, we used system dynamics, ANN, and CA-Markov to model a water ecological system. The social component was modeled according to Granger causality test by system dynamics. The natural component consists of the water resource and water environmental capacity, which were forecasted through the prediction of precipitation and change in land use cover. The interaction of the social component and the natural component mainly reflected environmental policies, such as the imposition of an environmental fee and environmental tax based on their values. Simulation results showed the different assessments on water ecological carrying capacity under the two policies. The population grew (2.9 million), and less pollution (86,632.37 t COD and 2854.5 t NH4N) was observed with the imposition of environmental tax compared with the imposition of an environmental fee (2.85 million population, 10,8381 t COD and 3543 t NH4N) at the same GDP level of 585 billion CNY in 2030. According to the causality loop, we discussed the different states under the policies and the reasons that caused the differences in water ecological carrying capacity state. According to game theory, we explained the limitation of the environmental fee policy on the basis of marginal benefit and cost. The externality was cleared up by the environmental tax policy. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Water ecological carrying capacity of urban lakes in the context of rapid urbanization: A case study of East Lake in Wuhan

    Science.gov (United States)

    Ding, Lei; Chen, Kun-lun; Cheng, Sheng-gao; Wang, Xu

    With the excessive development of social economy, water scarcity and water environment deterioration become a common phenomenon in metropolis. As a crucial component of urban water environment system, urban lake is mainly influenced by social economic system and tourism system. In this paper, a framework for quantitatively evaluating development sustainability of urban lake was established by a multi-objective model that represented water ecological carrying capacity (WECC). And nine key indicators including population, irrigation area, tourist quantity, the average number of hotel daily reception, TP, TN, CODMn, BOD5 were chosen from urban social-economy system and natural resilience aspects, with their index weight was determined by using the Structure Entropy Weight method. Then, we took Wuhan East Lake, the largest urban lake in China as a case study, and selected five time sections including 2002, 2004, 2007, 2009 and 2012 to synthetically evaluate and comparatively analyze the dynamic change of WECC. The results showed that: firstly, the water ecological carrying capacity values of the East Lake in five time sections were 1.17, 1.07, 1.64, 1.53 and 2.01 respectively, which all exceeded 1 and increased fluctuation. The rapid growth of population and GDP lead to sharply increasing demand for water quantity. However, a large amount of the domestic sewage and industrial waste led by economic development increases pressure on ecological environment of urban lakes. Secondly, the carrying capacity of the East Lake for tourist activities was still low. The value in 2012 was only 0.22, keeping at a slowly increasing phase, which indicates that the East Lake has large opportunity and space for developing the water resource carrying capacity and could make further efforts to attract tourists. Moreover, the WECC of the East Lake was mainly affected by rapid social and economic development and water environment damage caused by organic pollutants. From the view of urban

  15. Sustainability assessment of forest biomass supply chain at local scale: carrying capacity of the system for energy valorisation

    OpenAIRE

    Martire, S; Castellani, V.; Sala, S.

    2011-01-01

    Evaluation of the trade-off between the benefits coming from forest resources’ use and the conservation of forest ecosystems is needed. Considering the use of biomass for energy purpose, on one hand the use of wood resources should be based on an evaluation of the “carrying capacity” of the forest ecosystem and site-specific characteristics; on the other hand, the role of biomass valorisation has to be assessed considering the socio economic benefit or drawbacks due to the further development...

  16. Tourism monitoring system based on the concept of carrying capacity The case of the regional natural park Pfyn-Finges (Switzerland)

    OpenAIRE

    Michelet, Jacques Félix; Clivaz, Christophe; Hausser, Yves

    2004-01-01

    The creation of regional natural parks offers the possibility of improving the economic situation of peripheral regions. However, the use of ecologically sensitive zones for tourism also presents economic, environmental and social problems. The concept of carrying capacity is often presented as a useful approach for determining the intensity of tourism development that can be supported by a region. Our objective thus consisted in the operationalisation of this concept by defining a certain nu...

  17. 水环境承载能力及其测算研究%Study on Water Environment Carrying Capacity and Calculation

    Institute of Scientific and Technical Information of China (English)

    胡秋玲

    2014-01-01

    From the water resources carrying capacity situation,concept and connotation,three calculation methods for water environment carrying capacity is introduced,namely mathematical model, comprehensive index system evaluation and analytical method of multi-objective model of water environment carrying capacity,etc.At the same time,a brief analysis of the principle of three kinds of calculation methods and the advantages and disadvantages is conducted in order to draw attention to the relevant departments for always maintaining good water ecological system as the goal,strengthening the study on ecological water requirement,establishing the common model of water environment carrying capacity based on existing calculation models.%文章从水资源承载能力的现状、概念和内涵出发,介绍了3种常用的水环境承载能力测算方法,即数学模型法、综合指标体系评价方法和水环境承载力多目标模型分析方法。同时简要分析了3种测算方法的原理和优缺点,以期引起相关部门重视以水体始终保持良好生态系统为目标,加强生态需水量研究,在对现有测算模型进行融合贯通的基础上,建立能够综合反映水环境承载能力的通用评价模型。

  18. Capital humano y capacidad humana Human capital and human capacity

    Directory of Open Access Journals (Sweden)

    Sen Amartya Kumar

    1998-12-01

    Full Text Available En este articulo se examinan las relaciones y diferencias entre el concepto de 'capital humano' y el concepto de 'capacidad humana'. El concepto de capital humano es mas limitado puesto que solo concibe las cualidades humanas en su relación con el crecimiento económico mientras que el concepto de capacidades da énfasis a la expansión de libertad humana para vivir el tipo de vida que la gente considera valedera. Cuando se adopta esa visión mas amplia, el proceso de desarrollo no puede verse simplemente como un incremento del PIB sino como la expansión de la capacidad humana para llevar una vida mas libre y mas digna.In this article the relationships and the differences between the concept of 'human capital' and the concept of 'human capability' are examined. The concept of human capital is more limited since it only conceives human qualities in relation to economic growth, whereas the concept of capabili ties puts emphasis on the expansion of human freedom to live the kind of life that people judge valuable. Whenthis broader vision is adopted, the process of development cannot be seen as simply an increase in the GNP, but rather as the expansion of the human capability to live a more free and worthy life.

  19. The air-conditioning capacity of the human nose.

    Science.gov (United States)

    Naftali, Sara; Rosenfeld, Moshe; Wolf, Michael; Elad, David

    2005-04-01

    The nose is the front line defender of the respiratory system. Unsteady simulations in three-dimensional models have been developed to study transport patterns in the human nose and its overall air-conditioning capacity. The results suggested that the healthy nose can efficiently provide about 90% of the heat and the water fluxes required to condition the ambient inspired air to near alveolar conditions in a variety of environmental conditions and independent of variations in internal structural components. The anatomical replica of the human nose showed the best performance and was able to provide 92% of the heating and 96% of the moisture needed to condition the inspired air to alveolar conditions. A detailed analysis explored the relative contribution of endonasal structural components to the air-conditioning process. During a moderate breathing effort, about 11% reduction in the efficacy of nasal air-conditioning capacity was observed.

  20. Limited communication capacity unveils strategies for human interaction

    CERN Document Server

    Miritello, Giovanna; Cebrián, Manuel; Moro, Esteban

    2013-01-01

    Social connectivity is the key process that characterizes the structural properties of social networks and in turn processes such as navigation, influence or information diffusion. Since time, attention and cognition are inelastic resources, humans should have a predefined strategy to manage their social interactions over time. However, the limited observational length of existing human interaction datasets, together with the bursty nature of dyadic communications have hampered the observation of tie dynamics in social networks. Here we develop a method for the detection of tie activation/deactivation, and apply it to a large longitudinal, cross-sectional communication dataset ($\\approx$ 19 months, $\\approx$ 20 million people). Contrary to the perception of ever-growing connectivity, we observe that individuals exhibit a finite communication capacity, which limits the number of ties they can maintain active. In particular we find that men have an overall higher communication capacity than women and that this ...

  1. Human tool-making capacities reflect increased information-processing capacities: continuity resides in the eyes of the beholder.

    Science.gov (United States)

    Gibson, Kathleen R

    2012-08-01

    Chimpanzee/human technological differences are vast, reflect multiple interacting behavioral processes, and may result from the increased information-processing and hierarchical mental constructional capacities of the human brain. Therefore, advanced social, technical, and communicative capacities probably evolved together in concert with increasing brain size. Interpretations of these evolutionary and species differences as continuities or discontinuities reflect differing scientific perspectives.

  2. New approach for determination of an optimum honeybee colony's carrying capacity based on productivity and nectar secretion potential of bee forage species.

    Science.gov (United States)

    Al-Ghamdi, Ahmed; Adgaba, Nuru; Getachew, Awraris; Tadesse, Yilma

    2016-01-01

    The present study was carried out to determine an optimum honeybee colony's carrying capacity of selected valleys dominated by Ziziphus spina-christi and Acacia tortilis in the Al-Baha region, Kingdom of Saudi Arabia. The study was conducted based on the assessment of the number of colonies kept, their productivities and the existing productive bee forage resources in the target valleys with its economic implication. In the existing beekeeping practice, the average number of managed honeybee colonies introduced per square kilometer was 530 and 317 during the flowering period of Z. spina-christi and A. tortilis, respectively. Furthermore, the overall ratios of productive bee forage plants to the number of honeybee colonies introduced were 0.55 and 11.12 to Ziziphus trees and A. tortilis shrubs respectively. In the existing situation the average honey production potential of 5.21 and 0.34 kg was recorded per Ziziphus and A. tortilis plants per flowering season, respectively. The present study, revealed that the number of honeybee colonies introduced in relation to the existing bee forage potential was extremely overcrowding which is beyond the carrying capacity of bee forage resources in selected valleys and it has been observed to affect the productivities and subsequent profitability of beekeeping. The study infers that, by keeping the optimum honeybee colony's carrying capacity of valleys (88 traditional hives/km(2) or 54 Langstroth hives/km(2) in Ziziphus field and 72 traditional hives/km(2) or 44 Langstroth hives/km(2) in A. tortilis field), profitability of beekeeping can be boosted up to 130.39% and 207.98% during Z. spina-christi and A. tortilis, flowering seasons, respectively.

  3. Direct FEM-computation of load carrying capacity of highly loaded passive components; Direkte FEM - Berechnung der Tragfaehigkeit hochbeanspruchter passiver Komponenten

    Energy Technology Data Exchange (ETDEWEB)

    Staat, M.; Heitzer, M. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Sicherheitsforschung und Reaktortechnik

    1998-11-01

    Detailed, inelastic FEM analyses yield accurate information about the stresses and deformations in passive components. The local loading conditions, however, cannot be directly compared with a limit load in terms of structural mechanics. Concentration on the load carrying capacity is an approach simplifying the analysis. Based on the plasticity theory, limit and shakedown analyses calculate the load carrying capacities directly and exactly. The paper explains the implementation of the limit and shakedown data sets in a general FEM program and the direct calculation of the load carrying capacities of passive components. The concepts used are explained with respect to common structural analysis. Examples assuming high local stresses illustrate the application of FEM-based limit and shakedown analyses. The calculated interaction diagrams present a good insight into the applicable operational loads of individual passive components. The load carrying analysis also opens up a structure mechanics-based approach to assessing the load-to-collapse of cracked components made of highly ductile fracture-resistant material. (orig./CB) [Deutsch] Genaue Kenntnis der Spannungen und Verformungen in passiven Komponenten gewinnt man mit detailierten inelastischen FEM Analysen. Die lokale Beanspruchung laesst sich aber nicht direkt mit einer Beanspruchbarkeit im strukturmechanischen Sinne vergleichen. Konzentriert man sich auf die Frage nach der Tragfaehigkeit, dann vereinfacht sich die Analyse. Im Rahmen der Plastizitaetstheorie berechnen Traglast- und Einspielanalyse die tragbaren Lasten direkt und exakt. In diesem Beitrag wird eine Implementierung der Traglast- und Einspielsaetze in ein allgemeines FEM Programm vorgestellt, mit der die Tragfaehigkeit passiver Komponenten direkt berechnet wird. Die benutzten Konzepte werden in Bezug auf die uebliche Strukturanalyse erlaeutert. Beispiele mit lokal hoher Beanspruchung verdeutlichen die Anwendung der FEM basierten Traglast- und

  4. ORIGINATION AND DEVELOPMENT OF THE CONCEPT OF AQUATIC ECOLOGICAL CARRYING CAPACITY IN THE BASIN%流域水生态承载力研究的起源和发展

    Institute of Scientific and Technical Information of China (English)

    曾晨; 刘艳芳; 张万顺; 汤弟伟

    2011-01-01

    . From the perspective of estimation and assessment,approaches in evaluating ecological carrying capacity such as net primary production,ecological footprint, sustainable development and the health of ecological system are the primary approaches of measuring, which is the basis of estimating watershed ecological carrying capacity. Currently, the research on the aquatic ecological carrying capacity in the basin is at the initial stage. In the future,it should better reflect the fundamental aim of the harmonious coexistence between human and nature and the dialectical integration of quality and quantity. Meanwhile, the employment of the research approach which integrates material, energy, information, time and space is expected to make the research on the aquatic ecological carrying capacity in the basin more practical.

  5. Allocation of cognitive processing capacity during human autonomic classical conditioning.

    Science.gov (United States)

    Dawson, M E; Schell, A M; Beers, J R; Kelly, A

    1982-09-01

    expected UCS. Fourth, large electrodermal responders to the CSs exhibited patterns of capacity allocation during the CSs, particularly during the CS+, different from those of small electrodermal responders. In particular, they exhibited significantly longer RTs at 300 msec after CS+ onset than did the small responders, followed by a shortening of RT at 500 msec relative to the small responders. This finding suggests that large electrodermal responders devote greater processing capacity to significant environmental stimuli than do small responders and that their processing may begin and be completed more rapidly. All in all, the data indicate the complexity of the cognitive processes that occur during human classical conditioning and the usefulness of the secondary-task technique in integrating conditioning theories and psychophysiology with cognitive psychology.

  6. Problem in application carrying capacity approach for land allocation assessment in Indonesian municipal spatial planning: A case of Kutai Kartanegara Regency

    Science.gov (United States)

    Wijaya, I. N. S.; Rahadi, B.; Lusiana, N.; Maulidina, I.

    2017-06-01

    Urbanization in many countries, such as Indonesia, is commonly appeared as a dynamic population of developed areas. It is followed with reducing rural uses of land for improving urban land uses such as housing, industry, infrastructure, etc. in response to the growth of population. One may not be sufficiently considered by the urban planners and the decision makers, urbanization also means escalation of natural resources consumption that should be supported by the natural capacity of the area. In this situation, balancing approach as carrying capacity calculation in spatial planning is needed for sustainability. Indonesian Spatial Planning Law 26/2007 has already expressed about the balance approach in the system. Moreover, it strictly regulates the assessment and the permission system in controlling land development, especially for the conversion. However, the reductions over the rural uses of land, especially agriculture, are continuously occurred. Concerning the planning approach, this paper aims to disclose common insufficiency of carrying capacity considerations in Indonesian spatial planning practice. This paper describes common calculation weaknesses in projecting area for the urban development by recalculating the actual gap between supply and demand of agriculture land areas. Here, municipal spatial plan of Kutai Kartanegara Regency is utilized as single sample case to discuss. As the result, the recalculation shows that: 1) there are serious deficit status of agriculture land areas in order to fulfil the demanded agriculture production for the existed population, 2) some calculation of agriculture production may be miss-interpreted because of insufficient explanation toward the productivity of each agriculture commodity.

  7. Interleukin 2 inhibits in vitro growth of human T cell lines carrying retrovirus.

    Science.gov (United States)

    Sugamura, K; Nakai, S; Fujii, M; Hinuma, Y

    1985-05-01

    Four human T cell lines, TL-Mor, TL-Su, TL-TerI, and TL-OmI, carrying human T cell leukemia virus (HTLV), were established previously. TL-Mor, TL-Su, and TL-TerI were derived from interleukin 2 (IL-2)-dependent parental cell lines cloned from peripheral blood leukocytes (PBL) of three healthy HTLV carriers, while TL-OmI was directly established from PBL of a patient with adult T cell leukemia. These four TL cell lines grow autonomously without IL-2. When they were cultured in the presence of IL-2, their growth was inhibited after a few days. This growth inhibition depended on the dose of IL-2, and the effective dose significantly promoted growth of their parental IL-2-dependent cell lines. The growth inhibition is demonstrated to be due to specific binding of IL-2 to receptors on the TL cells.

  8. Development of urbanization in arid and semi arid regions based on the water resource carrying capacity -- a case study of Changji, Xinjiang

    Science.gov (United States)

    Xiao, H.; Zhang, L.; Chai, Z.

    2017-07-01

    The arid and semiarid region in China where have a relatively weak economic foundation, independent development capacity, and the low-level of urbanization. The new urbanization within these regions is facing severe challenges brought by the constraints of resources. In this paper, we selected the Changji Hui Autonomous Prefecture, Xinjiang Uyghur Autonomous Region as study area. We found that agricultural planting structure is the key water consumption index based on the research about the main water demands of domestic, agriculture and industry. Finally, we suggest that more attentions should be paid to the rational utilization of water resources, population carrying capacity, and adjust and upgrade the industrial structure, with the purpose of coordination with the Silk Road Economic Belt.

  9. Studies about the current carrying capacity of the devices of the electric power transmission depending on the ambient conditions; Untersuchungen zur Strombelastbarkeit der Geraete der Elektroenergieuebertragung unter Freiluftatmosphaere

    Energy Technology Data Exchange (ETDEWEB)

    Berg, Ina

    2011-07-01

    Due to the liberalization of the electricity market and the increasing expansion of the generation of wind power the transport of electric power in the power grid is increasing. Due to that the electrical equipment is loaded higher up to its thermal limits. However the electrical power supply should be anytime reliable. Because the new construction and upgrade of overhead lines and substations is expensive and approval procedures can take up to ten years, solutions have to be found, to ensue in short and medium term the transport of electrical power through the power grid. In this paper a possibility is introduced and analyzed to increase the current carrying capacity of the electrical equipment without carrying out extensive reconstructions or new buildings. For that the method of thermal networks is used. For the different devices of the electric power transmission (overhead lines, electrical fittings, circuit-breaker, disconnecting switch and current transformer) thermal networks are designed. The heating on examples of all devices was studied and tested under laboratory conditions and the thermal networks were verified. By expansion of the thermal networks with elements for forced convection (wind velocity) and additional heat sources (solar radiation) the ambient conditions were considered. With the help of the so expanded thermal networks parameter studies depending on the wind velocity, ambient temperature and solar radiation were carried out. The studies showed that depending on the ambient conditions the current carrying capacity of all devices can be increased without changing the devices. The rated currents of all devices are specified for a high ambient temperature (e.g. 35 C) and low wind speed (e.g. 1 m/s). Most of the time in a year the ambient temperature is lower and the wind speed is higher than the specified values. So the devices can carry a higher current than the rated current without exceeding its thermal limits. The calculations show the

  10. Carrying capacity of coral reefs

    Digital Repository Service at National Institute of Oceanography (India)

    Wafar, M.V.M.

    The sustainable yield of a commercially exploited fishery is assessed by the biological and environmental factors (including fishing effort). These parameters with a reef are vastly diverse-size, location, species diversity, productivity type...

  11. Generation and Characterization of a genetic zebrafish model of SMA carrying the human SMN2 gene

    Directory of Open Access Journals (Sweden)

    Beattie Christine E

    2011-03-01

    Full Text Available Abstract Background Animal models of human diseases are essential as they allow analysis of the disease process at the cellular level and can advance therapeutics by serving as a tool for drug screening and target validation. Here we report the development of a complete genetic model of spinal muscular atrophy (SMA in the vertebrate zebrafish to complement existing zebrafish, mouse, and invertebrate models and show its utility for testing compounds that alter SMN2 splicing. Results The human motoneuron disease SMA is caused by low levels, as opposed to a complete absence, of the survival motor neuron protein (SMN. To generate a true model of SMA in zebrafish, we have generated a transgenic zebrafish expressing the human SMN2 gene (hSMN2, which produces only a low amount of full-length SMN, and crossed this onto the smn-/- background. We show that human SMN2 is spliced in zebrafish as it is in humans and makes low levels of SMN protein. Moreover, we show that an antisense oligonucleotide that enhances correct hSMN2 splicing increases full-length hSMN RNA in this model. When we placed this transgene on the smn mutant background it rescued the neuromuscular presynaptic SV2 defect that occurs in smn mutants and increased their survival. Conclusions We have generated a transgenic fish carrying the human hSMN2 gene. This gene is spliced in fish as it is in humans and mice suggesting a conserved splicing mechanism in these vertebrates. Moreover, antisense targeting of an intronic splicing silencer site increased the amount of full length SMN generated from this transgene. Having this transgene on the smn mutant fish rescued the presynaptic defect and increased survival. This model of zebrafish SMA has all of the components of human SMA and can thus be used to understand motoneuron dysfunction in SMA, can be used as an vivo test for drugs or antisense approaches that increase full-length SMN, and can be developed for drug screening.

  12. Antioxidant capacity of plasma after red wine intake in Human

    Directory of Open Access Journals (Sweden)

    M. Gianmmanco

    2009-01-01

    Full Text Available Aim: Antioxidant effects after consumption of red wine have been investigated in several studies but results are contradictory and the difference in the plasma antioxidant capacity (AC after intake of red wine between women and men has never been studies. This work purpose is manifold: to ascertain whether red wine intake modifies the human plasma AC; to study the behaviour of plasma AC of women in comparison with men and finally to investigate on the plasma uric acid concentration and its relationships with the plasma AC after red wine intake.

  13. Quantitative Evaluation of Sustainable Development and Eco-Environmental Carrying Capacity in Water-Deficient Regions:A Case Study in the Haihe River Basin, China

    Institute of Scientific and Technical Information of China (English)

    WANG Zhong-gen; LUO Yu-zhou; ZHANG Ming-hua; XIA Jun

    2014-01-01

    Quantitative assessment of development sustainability could be a challenge to regional management and planning, especially for areas facing great risks of water shortage. Surface-water decline and groundwater over-pumping have caused serious environmental problems and limited economic development in many regions all around the world. In this paper, a framework for quantitatively evaluating development sustainability was established with water-related eco-environmental carrying capacity (EECC) as the core measure. As a case study, the developed approach was applied to data of the Haihe River Basin, China, during 1998 through 2007. The overall sustainable development degree (SDD) is determined to be 0.39, suggesting that this rate of development is not sustainable. Results of scenario analysis revealed that overshoot, or resource over-exploitation, of the Basin’s EECC is about 20% for both population and economy. Based on conditions in the study area in 2007, in order to achieve sustainable development, i.e., SDD>0.70 in this study, the EECC could support a population of 108 million and gross domestic product (GDP) of 2.72 trillion CNY. The newly developed approach in quantifying eco-environmental carrying capacity is anticipated to facilitate sustainable development oriented resource management in water-deifcient areas.

  14. Giant panda (Ailuropoda melanoleuca) population dynamics and bamboo (subfamily Bambusoideae) life history: a structured population approach to examining carrying capacity when the prey are semelparous

    Science.gov (United States)

    Carter, J.; Ackleh, A.S.; Leonard, B.P.; Wang, Hongfang

    1999-01-01

    The giant panda, Ailuropoda melanoleuca, is a highly specialized Ursid whose diet consists almost entirely of various species of bamboo. Bamboo (Bambusoideae) is a grass subfamily whose species often exhibit a synchronous semelparity. Synchronous semelparity can create local drops in carrying capacity for the panda. We modeled the interaction of pandas and their bamboo food resources with an age structured panda population model linked to a natural history model of bamboo biomass dynamics based on literature values of bamboo biomass, and giant panda life history dynamics. This paper reports the results of our examination of the interaction between pandas and their bamboo food resource and its implications for panda conservation. In the model all panda populations were well below the carrying capacity of the habitat. The giant panda populations growth was most sensitive to changes in birth rates and removal of reproductive aged individuals. Periodic starvation that has been documented in conjunction with bamboo die-offs is probably related to the inability to move to other areas within the region where bamboo is still available. Based on the results of this model, giant panda conservation should concentrate on keeping breeding individuals in the wild, keep corridors to different bamboo species open to pandas, and to concentrate research on bamboo life history.

  15. MCP-1 binds to oxidized LDL and is carried by lipoprotein(a) in human plasma

    Science.gov (United States)

    Wiesner, Philipp; Tafelmeier, Maria; Chittka, Dominik; Choi, Soo-Ho; Zhang, Li; Byun, Young Sup; Almazan, Felicidad; Yang, Xiaohong; Iqbal, Navaid; Chowdhury, Punam; Maisel, Alan; Witztum, Joseph L.; Handel, Tracy M.; Tsimikas, Sotirios; Miller, Yury I.

    2013-01-01

    Lipoprotein oxidation plays an important role in pathogenesis of atherosclerosis. Oxidized low density lipoprotein (OxLDL) induces profound inflammatory responses in vascular cells, such as production of monocyte chemoattractant protein-1 (MCP-1) [chemokine (C-C motif) ligand 2], a key chemokine in the initiation and progression of vascular inflammation. Here we demonstrate that OxLDL also binds MCP-1 and that the OxLDL-bound MCP-1 retains its ability to recruit monocytes. A human MCP-1 mutant in which basic amino acids Arg-18 and Lys-19 were replaced with Ala did not bind to OxLDL. The MCP-1 binding to OxLDL was inhibited by the monoclonal antibody E06, which binds oxidized phospholipids (OxPLs) in OxLDL. Because OxPLs are carried by lipoprotein(a) [Lp(a)] in human plasma, we tested to determine whether Lp(a) binds MCP-1. Recombinant wild-type but not mutant MCP-1 added to human plasma bound to Lp(a), and its binding was inhibited by E06. Lp(a) captured from human plasma contained MCP-1 and the Lp(a)-associated endogenous MCP-1 induced monocyte migration. These results demonstrate that OxLDL and Lp(a) bind MCP-1 in vitro and in vivo and that OxPLs are major determinants of the MCP-1 binding. The association of MCP-1 with OxLDL and Lp(a) may play a role in modulating monocyte trafficking during atherogenesis. PMID:23667177

  16. Consciousness: a neural capacity for objectivity, especially pronounced in humans.

    Science.gov (United States)

    Dijker, Anton J M

    2014-01-01

    Consciousness tends to be viewed either as subjective experience of sensations and feelings, or as perception and internal representation of objects. This paper argues that neither view sufficiently acknowledges that consciousness may refer to the brain's most adaptive property: its capacity to produce states of objectivity. It is proposed that this capacity relies on multiple sensorimotor networks for internally representing objects and their properties in terms of expectancies, as well as on motivational and motor mechanisms involved in exploration, play, and care for vulnerable living and non-living objects. States of objectivity are associated with a very special phenomenal aspect; the experience that subjective aspects are absent and one is "just looking" at the world as it really is and can be. However, these states are normally closely preceded and followed by (and tend to be combined or fused with) sensations and feelings which are caused by activation of sensory and motivational mechanisms. A capacity for objectivity may have evolved in different species and can be conceived as a common basis for other elusive psychological properties such as intelligence, conscience, and esthetic experience; all three linked to crucial behaviors in human evolution such as tool making, cooperation, and art. The brain's pervasive tendency to objectify may be responsible for wrongly equating consciousness with feelings and wrongly opposing it to well-learned or habitual ("unconscious") patterns of perception and behavior.

  17. Consciousness: A neural capacity for objectivity, especially pronounced in humans

    Directory of Open Access Journals (Sweden)

    Anton J. M. Dijker

    2014-03-01

    Full Text Available Consciousness either tends to be viewed as subjective experience of sensations and feelings, or as perception and internal representation of objects. This paper argues that neither view sufficiently acknowledges that consciousness may refer to the brain’s most adaptive property: Its capacity to produce states of objectivity. It is proposed that this capacity relies on multiple sensorimotor networks for internally representing objects and their properties in terms of expectancies, as well as on motivational and motor mechanisms involved in exploration, play, and care for vulnerable living and nonliving objects. States of objectivity are associated with a very special phenomenal aspect; the experience that subjective aspects are absent and one is just looking at the world as it really is and can be. However, these states are normally closely preceded and followed by (and tend to be combined or fused with sensations and feelings which are caused by activation of sensory and motivational mechanisms. A capacity for objectivity may have evolved in different species and can be conceived as a common basis for other elusive psychological properties such as intelligence, conscience, and aesthetic experience; all three linked to crucial behaviors in human evolution such as tool making, cooperation, and art. The brain’s pervasive tendency to objectify may be responsible for wrongly equating consciousness with feelings and wrongly opposing it to well-learned or habitual (unconscious patterns of perception and behavior.

  18. Fuzzy assessment of water resources carrying capacity in Taihu Basin%太湖流域水资源承载能力模糊综合评价

    Institute of Scientific and Technical Information of China (English)

    孙远斌; 高怡; 石亚东; 徐枫

    2011-01-01

    Based on fully considering the status of water resources development and utilization and the socio-economic development in the Taihu Basin, a comprehensive evaluation index system of the water resources carrying capacity was established by using Driving forces-Pressure-State-Impact-Response (DPSIR) model, which put emphasis on the ecological environment impact factors and met the characteristics of the Taihu Basin.The indexes were classified according to water resources status, water resources and socio-economic and water resources and ecological environment.The AHP method was used to calculate the weights of each index and the fuzzy comprehensive evaluation of water resource carrying capacity in the Taihu Basin was carried out from 2000 to 2006.The evaluation results indicated that the overall level of the water resources carrying capacity in the Taihu Basin was contained in a critical state with the fitness and the overload, and its enhancement room was limited.%在充分考虑太湖流域水资源开发利用现状及社会经济发展状况的基础上,采用驱动力-压力-状态-影响-反应模型,突出生态环境影响因子,建立符合太湖流域自身特点的水资源承载能力综合评价指标体系,并按照水资源状态、水资源与社会经济、水资源与生态环境3个方面对指标进行分类,运用层次分析法计算各指标权重,对太湖流域2000-2006年水资源承载能力进行模糊综合评价.评价结果表明,太湖流域水资源承载能力总体水平处于适载与超载的临界状态,提升空间有限.

  19. 以崇左市为例的区域自然资源承载力研究%Study on Regional Natural Resource Carrying Capacity in Chongzuo City

    Institute of Scientific and Technical Information of China (English)

    覃玲玲

    2011-01-01

    Natural resource carrying capacity is important to the regional development and development scale. Through establishing the mathematical model of water resources carrying capacity, land resources carrying capacity and mineral resources carrying capacity, the methods of calculating and evaluating the natural resource carrying capacity were explored. Then taking Chongzuo as a example, the natural resource carrying capacity that in the year of 2010,2015,2020 were calculated, and the evaluation had been made that between the natural resource carrying capacity and the development. Conclusions were: Chongzuo have relatively large potential of water resources carrying capacity; carrying capacity of water resources don't overload in present and future; the carrying capacity of cultivated land resources overload in present, and the carrying capacity of construction land resources don't overload in present and future, these show that the land resource carrying capacity isn't safe; the mineral resources carrying capacity of limestone has relatively large potential to the economy; the mineral resources carrying capacity of coal and manganese ore will overload in 2015,2020.%通过建立水资源承载力、土地资源承载力、矿产资源承载力的数学模型,探索区域自然资源承载力的计算和评价方法;并以崇左市为例,计算崇左市2010现状年和2015年、2020年的自然资源承载力,然后评价自然资源对区域人口、经济社会发展及发展规模的承载能力.结果表明,崇左市水资源对区域的发展具有较好的承载能力,现状及未来均未出现超载;土地资源承载力中耕地资源承载力的现状已超载,建设用地资源承载力现状及未来均未超载,表明崇左市土地资源承载力存在一定安全隐患;矿产资源中水泥用石灰岩对经济发展的承载能力较强,煤炭和锰矿资源承载力在2015年和2020年均会超载.

  20. Spatial partitioning between species of the phytoplankton-feeding guild on an estuarine intertidal sand flat and its implication on habitat carrying capacity

    Science.gov (United States)

    Tamaki, Akio; Nakaoka, Ayumi; Maekawa, Hideki; Yamada, Fumihiko

    2008-07-01

    The fishery yield of Manila clams, Ruditapes philippinarum, increased considerably in the 1970s but has decreased rapidly since the middle 1980s on extensive intertidal sand flats in Ariake Sound (Kyushu, Japan). A survey conducted in 2004 on a 3.4-km 2 sand flat located in the central part of the Sound (Shirakawa sand flat) revealed four dominant species: two thalassinidean shrimps ( Upogebia major and Nihonotrypaea japonica), which are deep-reaching burrow dwellers with strong bioturbation activities, and two bivalves ( Mactra veneriformis and R. philippinarum). All four species belong to a phytoplankton (diatom)-feeding guild. In the late 1970s, the Manila clam population prevailed in high densities over the entire sand flat, whereas its distribution was restricted to the lowest quarter of the shore in 2004. In contrast, the population sizes and zones of occurrence of the other phytoplankton feeders have expanded in the absence of R. philippinarum, perhaps an indication of competitive release. After establishment, effects of the thalassinidean shrimps on sediment stability appear to have further reduced clam abundances. Across the sand flat in 2004, wet weight population biomass estimates for N. japonica, U. major, M. veneriformis, and R. philippinarum (whole body for shrimps and soft tissue for bivalves) were 304, 111, 378, and 234 tonnes, respectively. Based on Manila clam fishery yield records from Shirakawa, the carrying capacity of the Shirakawa sand flat in the late 1970s was estimated to be two times greater than the sum value for the whole phytoplankton-feeding guild in 2004. It is hypothesized that (1) the amount of phytoplankton determines the carrying capacity for the benthic community on the Shirakawa sand flat, with both phytoplankton and benthic biomass at maxima in the late 1970s, and (2) the subsequent increases in competition for space have caused further declines in the Manila clam population biomass to approximately one-eighth of its past

  1. Leptin Effects on the Regenerative Capacity of Human Periodontal Cells

    Directory of Open Access Journals (Sweden)

    Marjan Nokhbehsaim

    2014-01-01

    Full Text Available Obesity is increasing throughout the globe and characterized by excess adipose tissue, which represents a complex endocrine organ. Adipose tissue secrets bioactive molecules called adipokines, which act at endocrine, paracrine, and autocrine levels. Obesity has recently been shown to be associated with periodontitis, a disease characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium, and also with compromised periodontal healing. Although the underlying mechanisms for these associations are not clear yet, increased levels of proinflammatory adipokines, such as leptin, as found in obese individuals, might be a critical pathomechanistic link. The objective of this study was to examine the impact of leptin on the regenerative capacity of human periodontal ligament (PDL cells and also to study the local leptin production by these cells. Leptin caused a significant downregulation of growth (TGFβ1, and VEGFA and transcription (RUNX2 factors as well as matrix molecules (collagen, and periostin and inhibited SMAD signaling under regenerative conditions. Moreover, the local expression of leptin and its full-length receptor was significantly downregulated by inflammatory, microbial, and biomechanical signals. This study demonstrates that the hormone leptin negatively interferes with the regenerative capacity of PDL cells, suggesting leptin as a pathomechanistic link between obesity and compromised periodontal healing.

  2. African dust carries microbes across the ocean: are they affecting human and ecosystem health?

    Science.gov (United States)

    Kellogg, Christina A.; Griffin, Dale W.

    2003-01-01

    Atmospheric transport of dust from northwest Africa to the western Atlantic Ocean region may be responsible for a number of environmental hazards, including the demise of Caribbean corals; red tides; amphibian diseases; increased occurrence of asthma in humans; and oxygen depletion (eutrophication) in estuaries. Studies of satellite images suggest that hundreds of millions of tons of dust are trans-ported annually at relatively low altitudes across the Atlantic Ocean to the Caribbean Sea and southeastern United States. The dust emanates from the expanding Sahara/Sahel desert region in Africa and carries a wide variety of bacteria and fungi. The U.S. Geological Survey, in collaboration with the NASA/Goddard Spaceflight Center, is conducting a study to identify microbes--bacteria, fungi, viruses--transported across the Atlantic in African soil dust. Each year, millions of tons of desert dust blow off the west African coast and ride the trade winds across the ocean, affecting the entire Caribbean basin, as well as the southeastern United States. Of the dust reaching the U.S., Florida receives about 50 percent, while the rest may range as far north as Maine or as far west as Colorado. The dust storms can be tracked by satellite and take about one week to cross the Atlantic.

  3. 农业生产与水资源承载力评价%Agricultural production and evaluation in terms of water resources carrying capacity

    Institute of Scientific and Technical Information of China (English)

    虞祎; 张晖; 胡浩

    2016-01-01

    AbstractBased on the evaluation of water resources carrying capacity, especially taking into account the impact of agricultural pollution on sustainable use of water resources, a comprehensive analysis was conducted on the strains of water resources due to farming and animal production in different regions of China to provide reference for rational estimation of potential agricultural growth and correct approaches for structural adjustments in agriculture. Excess nitrogen and grey water were calculated as indicators to quantify the impact of agricultural pollution on water resources. Following nutrient balance theory, excess nitrogen was the difference between the sum of nitrogen provided by chemical fertilizer, livestock manure and soil, and total nitrogen needed by farming. Grey water was the amount of water required for diluting excessively high concentration of nitrogen in water to a more environmental-friendly level. Agricultural water footprint was the sum of agricultural water and grey water used. The huge quantity of excess nitrogen produced by farming and livestock consequently led to excessive amount of grey water, which more than doubled the amount of water used in agriculture. There was therefore the need to reserve enough environmental space for diluting pollution when estimating water resources carrying capacity based on water sustainability and healthy development. Water surplus were constructed to reflect the potential of water resources to support agricultural production with detailed environmental consideration. Water surplus was the difference between water resources and agricultural water footprint. Using 2003-2012 nationwide samples, a panel data model was constructed to analyze the impact of change in sown area and livestock head on water surplus. The results suggested that the nationwide water in China could carry a maximum of 168.89 million hm2 or 3.57 billion pigs. The water resources carrying capacity model results also showed that the

  4. Study on Macao's Comprehensive Land Carrying Capacity%澳门土地综合承载状况研究

    Institute of Scientific and Technical Information of China (English)

    陈相

    2012-01-01

    作为亚太有名的微型经济体,澳门有限的土地资源是备受关注以及重视的生产要素,它的规模以及承载上限直接制约着澳门经济与社会的可持续发展。通过对澳门土地综合承载状况进行实证研究发现,澳门目前显示处于超载的状态,经济与社会的发展给澳门土地所赋予的压力已超过澳门的承载上限。为了促进澳门的可持续发展,需要从完善规划和增加土地等多方面不断提高土地的承载上限。%As one of the micro economies in Asia-pacific, Macao has a limited land resource, which constitutes a major factor of production. The fact is its scale and maximum limit of carrying is impeding the development of its economy and society at large. The empirical analysis on Macao's comprehensive land carrying capacity finds Macao already surcharged. To seek for sustainable developments, Macao must raise the limit of land carrying by means of promoting city planning and adding land.

  5. Yeast NDI1 Improve Oxidative Phosphorylation Capacity and Increases Protection Against Oxidative Stress and Cell Death in Cells Carrying a Leber’s Hereditary Optic Neuropathy Mutation

    OpenAIRE

    Park, Jeong Soon; Li, You-Fen; Bai, Yidong

    2007-01-01

    G11778A in the subunit ND4 gene of NADH dehydrogenase complex is the most common primary mutation found in Leber’s hereditary optic neuropathy (LHON) patients. The NDI1 gene, which encodes the internal NADH -quinone oxidoreductase in Saccharomyces cerevisiae, was introduced into the nuclear genome of a mitochondrial defective human cell line, Le1.3.1, carrying the G11778A mutation. In transformant cell lines, LeNDI1-1 and -2, total and complex I-dependent respiration were fully restored and l...

  6. Establishment of transgenic mice carrying gene encoding human zinc finger protein 191

    Science.gov (United States)

    Li, Jian-Zhong; Chen, Xia; Yang, Hua; Wang, Shui-Liang; Gong, Xue-Lian; Feng, Hao; Guo, Bao-Yu; Yu, Long; Wang, Zhu-Gang; Fu, Ji-Liang

    2004-01-01

    AIM: Human zinc finger protein 191 (ZNF191) was cloned and characterized as a Krüppel-like transcription factor, which might be relevant to many diseases such as liver cancer, neuropsychiatric and cardiovascular diseases. Although progress has been made recently, the biological function of ZNF191 remains largely unidentified. The aim of this study was to establish a ZNF 191 transgenic mouse model, which would promote the functional study of ZNF191. METHODS: Transgene fragments were microinjected into fertilized eggs of mice. The manipulated embryos were transferred into the oviducts of pseudo-pregnant female mice. The offsprings were identified by PCR and Southern blot analysis. ZNF 191 gene expression was analyzed by RT-PCR. Transgenic founder mice were used to establish transgenic mouse lineages. The first generation (F1) and the second generation (F2) mice were identified by PCR analysis. Ten-week transgenic mice were used for pathological examination. RESULTS: Four mice were identified as carrying copies of ZNF191 gene. The results of RT-PCR showed that ZNF 191 gene was expressed in the liver, testis and brain in one of the transgenic mouse lineages. Genetic analysis of transgenic mice demonstrated that ZNF 191 gene was integrated into the chromosome at a single site and could be transmitted stably. Pathological analysis showed that the expression of ZNF 191 did not cause obvious pathological changes in multiple tissues of transgenic mice. CONCLUSION: ZNF 191 transgenic mouse model would facilitate the investigation of biological functions of ZNF191 in vivo. PMID:14716836

  7. Weaving versus blending: a quantitative assessment of the information carrying capacities of two alternative methods for conveying multivariate data with color.

    Science.gov (United States)

    Hagh-Shenas, Haleh; Kim, Sunghee; Interrante, Victoria; Healey, Christopher

    2007-01-01

    In many applications, it is important to understand the individual values of, and relationships between, multiple related scalar variables defined across a common domain. Several approaches have been proposed for representing data in these situations. In this paper we focus on strategies for the visualization of multivariate data that rely on color mixing. In particular, through a series of controlled observer experiments, we seek to establish a fundamental understanding of the information-carrying capacities of two alternative methods for encoding multivariate information using color: color blending and color weaving. We begin with a baseline experiment in which we assess participants' abilities to accurately read numerical data encoded in six different basic color scales defined in the L*a*b* color space. We then assess participants' abilities to read combinations of 2, 3, 4 and 6 different data values represented in a common region of the domain, encoded using either color blending or color weaving. In color blending a single mixed color is formed via linear combination of the individual values in L*a*b* space, and in color weaving the original individual colors are displayed side-by-side in a high frequency texture that fills the region. A third experiment was conducted to clarify some of the trends regarding the color contrast and its effect on the magnitude of the error that was observed in the second experiment. The results indicate that when the component colors are represented side-by-side in a high frequency texture, most participants' abilities to infer the values of individual components are significantly improved, relative to when the colors are blended. Participants' performance was significantly better with color weaving particularly when more than 2 colors were used, and even when the individual colors subtended only 3 minutes of visual angle in the texture. However, the information-carrying capacity of the color weaving approach has its limits. We

  8. Working memory capacity predicts dopamine synthesis capacity in the human striatum.

    NARCIS (Netherlands)

    Cools, R.; Gibbs, S.E.; Miyakawa, A.; Jagust, W.; D'Esposito, M.

    2008-01-01

    Evidence from psychopharmacological research has revealed that dopamine receptor agents have opposite effects on cognitive function depending on baseline levels of working memory capacity. These contrasting effects have been interpreted to reflect differential baseline levels of dopamine. Here we de

  9. Working memory capacity predicts dopamine synthesis capacity in the human striatum.

    NARCIS (Netherlands)

    Cools, R.; Gibbs, S.E.; Miyakawa, A.; Jagust, W.; D'Esposito, M.

    2008-01-01

    Evidence from psychopharmacological research has revealed that dopamine receptor agents have opposite effects on cognitive function depending on baseline levels of working memory capacity. These contrasting effects have been interpreted to reflect differential baseline levels of dopamine. Here we

  10. Barrier Capacity of Human Placenta for Nanosized Materials

    Science.gov (United States)

    Wick, Peter; Malek, Antoine; Manser, Pius; Meili, Danielle; Maeder-Althaus, Xenia; Diener, Liliane; Diener, Pierre-Andre; Zisch, Andreas; Krug, Harald F.; von Mandach, Ursula

    2010-01-01

    Background Humans have been exposed to fine and ultrafine particles throughout their history. Since the Industrial Revolution, sources, doses, and types of nanoparticles have changed dramatically. In the last decade, the rapidly developing field of nanotechnology has led to an increase of engineered nanoparticles with novel physical and chemical properties. Regardless of whether this exposure is unintended or not, a careful assessment of possible adverse effects is needed. A large number of projects have been carried out to assess the consequences of combustion-derived or engineered nanoparticle exposure on human health. In recent years there has been a growing concern about the possible health influence of exposure to air pollutants during pregnancy, hence an implicit concern about potential risk for nanoparticle exposure in utero. Previous work has not addressed the question of whether nanoparticles may cross the placenta. Objective In this study we investigated whether particles can cross the placental barrier and affect the fetus. Methods We used the ex vivo human placental perfusion model to investigate whether nanoparticles can cross this barrier and whether this process is size dependent. Fluorescently labeled polystyrene beads with diameters of 50, 80, 240, and 500 nm were chosen as model particles. Results We showed that fluorescent polystyrene particles with diameter up to 240 nm were taken up by the placenta and were able to cross the placental barrier without affecting the viability of the placental explant. Conclusions The findings suggest that nanomaterials have the potential for transplacental transfer and underscore the need for further nanotoxicologic studies on this important organ system. PMID:20064770

  11. Finite element analysis of steel bar truss slab load-carrying capacity%钢筋桁架楼板承载力有限元分析

    Institute of Scientific and Technical Information of China (English)

    赵建忠; 孙磊; 王干

    2015-01-01

    钢筋桁架楼板在工程中的应用日益广泛,深入研究该楼板的受力性能有利于指导实际工程应用。文章采用有限元分析软件ANSYS对钢筋桁架楼板进行单调静力加载模拟,通过正交试验的方法对剪跨比、底部压型钢板、腹杆等影响因素进行研究。结果表明:楼板进入弹塑性阶段以后,试验中的4块带钢板的桁架楼板极限弯矩可提高30%左右,同时斜腹杆以及楼板的剪跨比对承载力也有较大的影响。对钢筋桁架楼板正截面受弯承载力计算公式进行补充和修改,达到了减轻结构自重、降低工程造价的目的。%In order to make a deep research on the structural behavior of steel bar truss slab,the FEM ANSYS was used to simulate monotonic static loading process of the slab. Through the analysis of different value of parameters of shear-span ratio,steel sheeting,diagonal web member,the same conclusion with the influence pattern of rigidity was achieved as well as the test. According to the results of the test,the formula of load-carrying capacity is advanced for future reference. Also,the shear-span ratio and diagonal web member will impact the capacity. Due to the beneficial effects of steel slabs were not considered,the suggestion was put forward to improve the correlation formulasto ease the weight of the structure and reduce the construction cost.

  12. Range Analysis and Terrain Preference of Adult Southern White Rhinoceros (Ceratotherium simum) in a South African Private Game Reserve: Insights into Carrying Capacity and Future Management.

    Science.gov (United States)

    Thompson, S; Avent, T; Doughty, L S

    2016-01-01

    The Southern white rhinoceros (Ceratotherium simum) is a threatened species, central to the tourism appeal of private game reserves in South Africa. Privately owned reserves in South Africa tend to be smaller than government run reserves such as Kruger National Park. Because of their relatively small size and the often heterogeneous nature of the landscape private game reserve managers benefit from detailed knowledge of white rhinoceros terrain selection preferences, which can be assessed from their ranging behaviours. We collected adult and sub-adult white rhinoceros distribution data over a 15 month period, calculating individual range size using kernel density estimation analysis within a GIS. From this, terrain selectivity was calculated using 50% and 95% kernels to extract terrain composition values. Jacob's correction of the Ivlev's selectivity index was subsequently applied to the terrain composition of each individual to identify trends in selectivity. Results reveal that adult males hold exclusive territories considerably smaller than those found in previous work conducted in "open" or large reserves. Similarly, results for the size of male versus female territories were also not in keeping with those from previous field studies, with males, rather than females, having the larger territory requirement. Terrain selection for both genders and age classes (adult and sub-adult) showed a strong preference for open grassland and avoidance of hill slope and riparian terrains. This research reveals white rhinoceros terrain selection preferences and how they influence range requirements in small, closed reserves. We conclude that this knowledge will be valuable in future white rhinoceros conservation management in small private game reserves, particularly in decisions surrounding removal of surplus individuals or augmentation of existing populations, calculation of reserve carrying capacity and future private reserve acquisition.

  13. Is DOM driver of the microbial carrying capacity in pristine porous groundwater ecosystems? - lab-scale experiments in 2D sediment flow-through microcosms

    Science.gov (United States)

    Hofmann, Roland; Griebler, Christian

    2017-04-01

    Groundwater ecosystems are an essential resource for drinking water and at the same time constitute fascinating habitats subject to increasing (anthropogenic) disturbances. In our research, we look for ways to qualitatively and quantitatively access, and predict the resistance and resilience (potential) of groundwater ecosystems in consequence of selected disturbances. As a central goal we hope to identify and quantify the underlying biological and ecological key drivers of the microbial Carrying Capacity (mCC) - an ecological concept established in macro-ecology - we assume directly connected to the ecosystem's productivity and the resistance and resilience of aquifers. We further hypothesize, that the ecosystems' mCC is a result of available energy and constitutes a promising proxy for the potential of groundwater ecosystems to withstand impacts and recover from it. In a first approach we studied the dynamics of the microbial standing stock (biomass) and growth (productivity) productivity of a natural groundwater microbial community in parallel 2-D sediment flow-through systems. Selected zones of the model aquifers were disturbed by elevated DOM concentrations. Both the 'mobile' (free floating) and 'sessile' (sediment attached) microbial components were followed over time in terms of biomass, growth, and specific activities (ATP, carbon use efficiency) and taxonomic composition. Sediment regions supplied with elevated concentrations of natural DOM showed increased biomass, activities and taxonomic richness with the sediment community, while differences in the mobile microbial were marginal. Specifically, the carbon use efficiency was significantly increased in the DOM amended sediment zones. In contrast, the microbial community that received the mainly refractory natural background DOM was able to metabolize polymers more efficiently in substrate use tests (ECOLOG), seen as an adaptation to the energy-poor subsurface. Quasi-stationary conditions were reached in

  14. Range Analysis and Terrain Preference of Adult Southern White Rhinoceros (Ceratotherium simum) in a South African Private Game Reserve: Insights into Carrying Capacity and Future Management

    Science.gov (United States)

    Thompson, S.; Doughty, L. S.

    2016-01-01

    The Southern white rhinoceros (Ceratotherium simum) is a threatened species, central to the tourism appeal of private game reserves in South Africa. Privately owned reserves in South Africa tend to be smaller than government run reserves such as Kruger National Park. Because of their relatively small size and the often heterogeneous nature of the landscape private game reserve managers benefit from detailed knowledge of white rhinoceros terrain selection preferences, which can be assessed from their ranging behaviours. We collected adult and sub-adult white rhinoceros distribution data over a 15 month period, calculating individual range size using kernel density estimation analysis within a GIS. From this, terrain selectivity was calculated using 50% and 95% kernels to extract terrain composition values. Jacob’s correction of the Ivlev’s selectivity index was subsequently applied to the terrain composition of each individual to identify trends in selectivity. Results reveal that adult males hold exclusive territories considerably smaller than those found in previous work conducted in “open” or large reserves. Similarly, results for the size of male versus female territories were also not in keeping with those from previous field studies, with males, rather than females, having the larger territory requirement. Terrain selection for both genders and age classes (adult and sub-adult) showed a strong preference for open grassland and avoidance of hill slope and riparian terrains. This research reveals white rhinoceros terrain selection preferences and how they influence range requirements in small, closed reserves. We conclude that this knowledge will be valuable in future white rhinoceros conservation management in small private game reserves, particularly in decisions surrounding removal of surplus individuals or augmentation of existing populations, calculation of reserve carrying capacity and future private reserve acquisition. PMID:27622566

  15. Generation of KCL035 research grade human embryonic stem cell line carrying a mutation in HBB gene

    Directory of Open Access Journals (Sweden)

    Heema Hewitson

    2016-03-01

    Full Text Available The KCL035 human embryonic stem cell line was derived from an embryo donated for research that carried a mutation in the HBB gene, which is linked to the β-thalassemia syndrome. The ICM was isolated using laser microsurgery and plated on γ-irradiated human foreskin fibroblasts. Both the derivation and cell line propagation were performed in an animal product-free environment. Pluripotent state and differentiation potential were confirmed by in vitro assays.

  16. Capacity building in human resources for health: The experience of the region of the Americas.

    Science.gov (United States)

    Godue, Charles; Cameron, Rick; Borrell, Rosa Maria

    2016-12-27

    Since the year 2003, most countries of the Region of the Americas have experienced sustained economic growth and inclusive development policies. In the health sector, achieving universal access became the overarching goal. However, the structural limitations of the health workforce represented a formidable obstacle to change. National Health Authorities were confronted with the challenge of developing critical capacities to redress entrenched inequalities in access to qualified health personnel. Under the auspices of the Pan American Health Organization, the Ministers of Health of the Region adopted, in September 2007, twenty regional goals for Human Resources for Health 2007-2015, aligned with the renewed strategy of Primary Health Care. Subsequently, a set of indicators and a methodology were developed to assess the goals and to monitor progress at the country level. Fifteen countries carried out a baseline assessment in 2009 or 2010 and conducted a second assessment in 2013. Although differences were noted across goals and between countries, the results suggested improvements in all twenty goals overall. The goals linked to the distribution of personnel, the management of migration, and the cooperation with education institutions appeared to be more resilient to change. The twenty Regional Goals for Human Resources for Health provided a common vision for action and a framework for cooperation within and among countries, and was a catalyst for change. Faced with evolving challenges, the countries should consider adopting a new shared agenda that builds on progress made and further supports intergovernmental policy alignment and capacity building in health workforce development, governance and management.

  17. Adult and Non-Formal Education: An Imperative for Human Capacity ...

    African Journals Online (AJOL)

    DR Nneka

    implementation of all this programmes; such as poor funding, inadequate provision of human and ... Through political education, people are aware of their civic ... developing human capacity to acquisition of skills for poverty alleviation,.

  18. Building the Capacity to Innovate: The Role of Human Capital. Research Report

    Science.gov (United States)

    Smith, Andrew; Courvisanos, Jerry; Tuck, Jacqueline; McEachern, Steven

    2012-01-01

    This report examines the link between human resource management practices and innovation. It is based on a conceptual framework in which "human resource stimuli measures"--work organisation, working time, areas of training and creativity--feed into innovative capacity or innovation. Of course, having innovative capacity does not…

  19. Proceedings from a Workshop on Ecological Carrying Capacity of Salmonids in the Columbia River Basin : Measure 7.1A of the Northwest Power Planning Council`s 1994 Fish and Wildlife Program : Report 3 of 4, Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Neitzel, D.A.; Mavros, William V.

    1996-05-01

    This report contains the proceedings of a workshop held during 1995 in Portland, Oregon. The objective of the workshop was to assemble a group of experts that could help us define carrying capacity for Columbia River Basin salmonids. The workshop was one activity designed to answer the questions asked in Measure 7.1A of the Council`s Fish and Wildlife Program. Based, in part, on the information we learned during the workshop we concluded that the approach inherent in 7.1A will not increase understanding of ecology, carrying capacity, or limiting factors that influence salmon under current conditions. Measure 7.1A requires a definition of carrying capacity and a list of determinants (limiting factors) of capacity. The implication or inference then follows that by asking what we know and do not know about the determinants will lead to research that increases our understanding of what is limiting salmon survival. It is then assumed that research results will point to management actions that can remove or repair the limiting factors. Most ecologists and fisheries scientists that have studied carrying capacity clearly conclude that this approach is an oversimplification of complex ecological processes. To pursue the capacity parameter, that is, a single number or set of numbers that quantify how many salmon the basin or any part of the basin can support, is meaningless by itself and will not provide useful information.

  20. General Measurement of Marine Ecological Carrying Capacity and Biological Immunology :A Case Study in Liaoning Province%基于生物免疫学理论的海域生态承载力综合测度研究——以辽宁省为例

    Institute of Scientific and Technical Information of China (English)

    狄乾斌; 吴佳璐; 张洁

    2013-01-01

    本研究根据海洋生态承载力对海洋生态系统健康的作用与人体免疫力对人体健康的维系作用的相似性,利用生物免疫学原理,构建了辽宁省海域生态承载状态综合测度指标体系,并进行了辽宁省海域2000年-2009年10年间的综合测度研究.结果表明:辽宁省海域自然承载力指数和承载力潜力指数整体分别呈下降和上升趋势,但是资源环境承载力总体却是波动下降趋势;人口与社会经济发展压力指数在2000年-2005年间波动较小,2006年呈现大幅度上升,之后稍有下降,总体上后期比前期增长较多.近几年来,辽宁省海域资源环境承载力的可持续发展状态较差,需要在海洋产业结构调整、污染治理和海洋科研方面加大力度.%Research on carrying capacity, regarded as the basis for the sustainable development of resources and the environment, is gaining more and more attention. With the growing popularity of marine issues, scholars are following the field of marine carrying capacity closely. Studies on marine carrying capacity are instrumental in planning economic development of coastal regions; however, most research findings are quantitative rather than qualitative. Because of the role of marine ecological carrying capacity in marine ecosystems is similar to the role of the human immune system in human health, we introduce a model of biological immunology using the Liaoning marine system as a case study. Numerical models such as entropy, discriminant models of sustainable development and fuzzy membership functions were used to calculate related index values. Results show that from 2000-2009 the natural carrying capacity index increased and the potential capacity index decreased, while overall carrying capacity experienced a floating decline. From 2000-2005 the pressure index of population and economic development was relatively stable, but after 2006 it encountered a sharp rise and then declined slightly with

  1. 西安市生态足迹与生态承载力动态变化与预测%Research on Dynamic Change Analysis and Prediction of Ecological Footprint and Ecological Carrying Capacity in Xi’an City

    Institute of Scientific and Technical Information of China (English)

    袁钟; 赵牡丹; 刘蕊娟; 王静

    2016-01-01

    Ecological footprint method by converting the regional resources and energy consumption to the area of various kinds of land of the production providing this kind of material flow , and compare with the same land area that can provide the ecological productive (ecological carrying capacity),it can quantitatively determine whether the development of a region in the scope of the ecological carrying capacity. In this paper, using the method of ecological footprint and ARIMA model to calculate account of biological and energy resources of ecological footprint of Xi' an from 1994 to 2013,and research on dynamic change,predict ecological footprint and ecological capacity in Xi ’an city.The results showed that ecological footprint is greater than the ecological capacity in Xi’an in 2013.ecological footprint is eight times of ecological carrying capacity from 1994 to 2013 in Xi 'an, and sustained severe ecological deficit. The intensity of production and life is more than the carrying capacity of the ecosystem, it ’s under the excessive exploitation and utilization of the human.ARIMA model prediction shows that the ecological footprint has a tendency in the next five years, but the gap between ecological footprint and ecological carrying capacity is very large. Through the analysis of influence degree of pressure of human activities on the natural ecological system.it can provide new train of thought and direction for urban ecological research, ecological construction and sustainable development . With strengthening the construction of urban ecological , optimizing the urban management mode and the industrial structure,it is an effective way to sustainable development and ecological security in Xi’an.%生态足迹法通过将区域的资源和能源消费转化为提供这种物质流所必须的各种生物生产土地的面积,并同区域能提供的生态生产型土地面积(生态承载力)进行比较,能定量判断一个区域的发展是否处于生

  2. Human germ cell formation in xenotransplants of induced pluripotent stem cells carrying X chromosome aneuploidies.

    Science.gov (United States)

    Dominguez, Antonia A; Chiang, H Rosaria; Sukhwani, Meena; Orwig, Kyle E; Reijo Pera, Renee A

    2014-09-22

    Turner syndrome is caused by complete or partial loss of the second sex chromosome and is characterized by spontaneous fetal loss in >90% of conceptions. Survivors possess an array of somatic and germline clinical characteristics. Induced pluripotent stem cells (iPSCs) offer an opportunity for insight into genetic requirements of the X chromosome linked to Turner syndrome. We derived iPSCs from Turner syndrome and control individuals and examined germ cell development as a function of X chromosome composition. We demonstrate that two X chromosomes are not necessary for reprogramming or maintenance of pluripotency and that there are minimal differences in gene expression, at the single cell level, linked to X chromosome aneuploidies. Formation of germ cells, as assessed in vivo through a murine xenotransplantation model, indicated that undifferentiated iPSCs, independent of X chromosome composition, are capable of forming germ-cell-like cells (GCLCs) in vivo. In combination with clinical data regarding infertility in women with X chromosome aneuploidies, results suggest that two intact X chromosomes are not required for human germ cell formation, qualitatively or quantitatively, but rather are likely to be required for maintenance of human germ cells to adulthood.

  3. Estimation of the human impact on nutrient loads carried by the Elbe River.

    Science.gov (United States)

    Hussian, Mohamed; Grimvall, Anders; Petersen, Wilhelm

    2004-01-01

    The reunification of Germany led to dramatically reduced emissions of nitrogen (N) and phosphorus (P) to the environment. The aim of the present study was to examine how these exceptional decreases influenced the amounts of nutrients carried by the Elbe River to the North Sea. In particular, we attempted to extract anthropogenic signals from time series of riverine loads of nitrogen and phosphorus by developing a normalization technique that enabled removal of natural fluctuations caused by several weather-dependent variables. This analysis revealed several notable downward trends. The normalized loads of total-N and NO3-N exhibited an almost linear trend, even though the nitrogen surplus in agriculture dropped dramatically in 1990 and then slowly increased. Furthermore, the decrease in total-P loads was found to be considerably smaller close to the mouth of the river than further upstream. Studying the predictive ability of different normalization models showed the following: (i) nutrient loads were influenced primarily by water discharge; (ii) models taking into account water temperature, load of suspended particulate matter, and salinity were superior for some combinations of sampling sites and nutrient species; semiparametric normalization models were almost invariably better than ordinary regression models.

  4. Physical inactivity and muscle oxidative capacity in humans

    DEFF Research Database (Denmark)

    Gram, Martin; Dahl, Rannvá; Dela, Flemming

    2014-01-01

    of proteins related to oxidative phosphorylation. With such a substantial down-regulation, it is likely that a range of adenosine triphosphate (ATP)-dependent pathways such as calcium signalling, respiratory capacity and apoptosis are affected by physical inactivity. However, this has not been investigated...

  5. Improving human resource capacity for road network preservation

    CSIR Research Space (South Africa)

    Nxumalo, M

    2010-10-01

    Full Text Available more than 210 courses since 1960 with more than 12 000 delegates having attended these courses. (SARF archives). This paper examines the extent and consequences of this lack of capacity in respect of the preservation of the road network in general...

  6. Anion conductance of the human red cell is carried by a maxi-anion channel

    DEFF Research Database (Denmark)

    Glogowska, Edyta; Dyrda, Agnieszka; Cueff, Anne

    2010-01-01

    played by serum in the recruitment of multiple new conductance levels showing very complex kinetics and gating properties upon serum addition. These channels, which seem to be dormant under normal physiological conditions, are potentially activable and could confer a far higher anion conductance...... channels proper has never been clarified, and the informations obtained by different groups of electrophysiologists are rather badly matched. This study, using the cell-attached configuration of the patch-clamp technique, rationalizes and explains earlier confusing results by demonstrating...... that the diversity of anionic channel activities recorded in human erythrocytes corresponds to different kinetic modalities of a unique type of maxi-anion channel with multiple conductance levels and probably multiple gating properties and pharmacology, depending on conditions. It demonstrates the role of activator...

  7. Human Serum Albumin Hybrid Incorporating Synthetic Hemes :A Novel O2-Carrying Hemoprotein

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Incorporation of synthetic heme (FeP) into recombinant human serum albumin(rHSA) provides an artificial hemoprotein(rHSA-FeP) which can bind and release oxygenreversibly under physiological conditions(in aqueous media, pH 7.3, 37 ℃) like hemoglobin(Hb) and myoglobin. An rHSA host absorbs maximally eight FeP molecules, and thesolution properties are almost identical to those of rHSA itself. The second-order structureand surface charge distribution of rHSA were always constant independent of the bindingnumbers of FeP. Its O2-binding ability satisfies the initial clinical requirements for red cellsubstitute. Although the NO-binding affinity is 8-fold high compared to the Hb's,administration of this fluid into rats showed negligible change in the blood pressure.Physiological responses to exchange transfusion with this rHSA-FeP into anaesthetized ratshave also been evaluated.

  8. Post-human and scientific research: how engineering carried out the project.

    Science.gov (United States)

    Ghilardi, Giampaolo; Accoto, Dino

    2014-01-01

    We start with a definition of robot in order to understand which are legitimate robotics' objectives. Then it is provided an outline of new robot generations and their industrial and biomedical applications. We consider the consequences of this new kind of technology on the notion of intelligence, stressing how the exteroceptive sensor systems provide a new bottom up approach to the AI debate. We consider three challenges Robotics have to face nowadays. First materials and components, which are built with technologies top-down, set huge limits in terms of weight, speed, safety and cost, not to mention reliability and durability. Second the methodological aspects: the challenge concerns the management of complexity. How to achieve intelligent and adaptive behaviours out of the control system of the robot, which must remain intrinsically simple? A third issue we address is the cultural one: the unreasonable expectations of the general public often provoked by a misunderstanding of the notion of intelligence itself. We consider then what makes human specifically human from a broader philosophic point of view, pointing out how the will is strangely absent in the AI debate. We show three advantages connected with this different perspective instead of the classical one intellect centered. First, while intellect is not used only by man, will is. Second, desire involves intellect while the reciprocal is not necessarily true. Third, looking at robotics and more specifically to cybernetics the key concept of these fields are control and governance, whereas both of them are specifically relate to the domain of will rather than intellect. We look then into the concept of participation as essential to the understanding of the notion of will, to overcome some roboethics' issues related to the adoption of the still dominant rationalistic paradigm.

  9. Watershed water ecological carrying capacity and optimizing regulation model%流域水生态承载力理论与优化调控模型方法

    Institute of Scientific and Technical Information of China (English)

    彭文启

    2013-01-01

    Watershed management is changing from single factor management of environment and re-sources to aquatic ecological protection integrated management. Water resources carrying capacity and water en-vironment carrying capacity have not fully adapted to this situation. Therefore,it is necessary to build a new car-rying capacity theory to solve the current aquatic problems. According to the demands of watershed water ecolog-ical integrity protection management,based on water ecological carrying capacity concept model,water ecologi-cal carrying capacity concept,which reveals its basic connotation of“partition,staging”property and“quanti-ty,quality,order”progressive comprehensive constraint effects,was put forward in this paper. Then the paper analyzed its key optimal regulation variables,and established the water ecological carrying capacity partition coupling concept model using eco-regions as elements. Considering the communication of water flow and water quality among eco-regions,the system dynamics simulation model of Taizi River basin water ecological carrying capacity was established,the water ecological carrying capacity of 8 eco-regions were simulated,and optional regulation schemes of each eco-regions were determined,which can provide a scientific basis for the sustainable development of the watershed.%  流域管理正在从环境及资源的单一要素管理向流域水生态系统综合管理转变,流域水生态承载力是流域水生态系统综合管理的基本理论。针对流域水生态完整性保护管理需求,建立了流域水生态承载力概念模型,提出了流域水生态承载力概念,揭示其“分区、分期”属性和“量、质、序”递进综合约束作用等基本内涵,通过分析其优化调控特性及优化调控关键变量,建立了流域水生态承载力分区耦合概念模型,形成了基于系统动力学方法的流域水生态承载力分区分期耦合模型方法,并以辽河

  10. Generation of KCL025 research grade human embryonic stem cell line carrying a mutation in NF1 gene

    Directory of Open Access Journals (Sweden)

    Heema Hewitson

    2016-03-01

    Full Text Available The KCL025 human embryonic stem cell line was derived from an embryo donated for research that carried an autosomal dominant mutation in the NF1 gene encoding neurofibromin (c.3739–3742 ΔTTTG. Mutations in this gene have been linked to neurofibromatosis type 1, juvenile myelomonocytic leukemia and Watson syndrome. The ICM was isolated using laser microsurgery and plated on γ-irradiated human foreskin fibroblasts. Both the derivation and cell line propagation were performed in an animal product-free environment. Pluripotent state and differentiation potential were confirmed by in vitro assays.

  11. Generation of KCL018 research grade human embryonic stem cell line carrying a mutation in the DMPK gene

    Directory of Open Access Journals (Sweden)

    Cristian Miere

    2016-03-01

    Full Text Available The KCL018 human embryonic stem cell line was derived from an embryo donated for research that carried an autosomal dominant mutation affecting one allele of the DMPK gene encoding the dystrophia myotonica protein kinase (2200 trinucleotide repeats; 14 for the normal allele. The ICM was isolated using laser microsurgery and plated on γ-irradiated human foreskin fibroblasts. Both the derivation and cell line propagation were performed in an animal product-free environment. Pluripotent state and differentiation potential were confirmed by in vitro assays.

  12. Generation of KCL028 research grade human embryonic stem cell line carrying a mutation in the HTT gene

    Directory of Open Access Journals (Sweden)

    Laureen Jacquet

    2016-03-01

    Full Text Available The KCL028 human embryonic stem cell line was derived from an embryo donated for research that carried an autosomal dominant mutation affecting one allele of the HTT gene encoding huntingtin (43 trinucleotide repeats; 21 for the normal allele. The ICM was isolated using laser microsurgery and plated on γ-irradiated human foreskin fibroblasts. Both the derivation and cell line propagation were performed in an animal product-free environment. Pluripotent state and differentiation potential were confirmed by in vitro and in vivo assays.

  13. Construction of lentivirus vectors carrying alphastatin gene and its secretion expression in human umbilical vein endothelia cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Objective To construct lentivirus vectors carrying alphastatin gene,test its secretion expression in human umbilical vein endothelia cells(HUVECs)and observe its effects on growth,migration and tube formation of HUVECs.Methods We constructed recombinant lentivirus vectors of NT4-alphastatin fusion gene containing neurotrophin-4 signal peptide,pro-region sequences and alphastatin,then transfected the recombinant lentivirus vectors into HUVECs to obtain secretory protein alphastatin and test its anti-angiogen...

  14. Antioxidant Capacity of Plasma after Pomegranate Intake in Human Volunteers

    Directory of Open Access Journals (Sweden)

    Hajimahmoodi Mannan

    2009-05-01

    Full Text Available Dietary antioxidants including phenolic compounds are believed to be effective nutrients in the prevention of oxidative stress related disease. Pomegranate has been used for centuries in ancient cultures for its medicinal purpose and is widely acknowledged for antioxidant properties. The present study was designed to assess the effect of pomegranate fresh fruit consumption on the plasma antioxidant capacity. Thirty healthy volunteers were recruited for the study. Volunteers were randomly divided into three groups (pomegranate, vitamin E and water consumption. Blood samples were collected, after at least 12 hours overnight fast, the day before beginning supplementation period and the day after supplementation had finished. Total antioxidant capacity measurement by FRAP method and clinical laboratory test were performed for all volunteers in two selected times. The obtained data revealed that consumption of 100 grams pomegranate and vitamin E per day for ten days resulted in a significant rise (14.05%, 8.28% plasma antioxidant capacity respectively, but this difference was not significant for water group.

  15. Generation and Characterization of a Transgenic Mouse Carrying a Functional Human β -Globin Gene with the IVSI-6 Thalassemia Mutation.

    Science.gov (United States)

    Breveglieri, Giulia; Mancini, Irene; Bianchi, Nicoletta; Lampronti, Ilaria; Salvatori, Francesca; Fabbri, Enrica; Zuccato, Cristina; Cosenza, Lucia C; Montagner, Giulia; Borgatti, Monica; Altruda, Fiorella; Fagoonee, Sharmila; Carandina, Gianni; Rubini, Michele; Aiello, Vincenzo; Breda, Laura; Rivella, Stefano; Gambari, Roberto; Finotti, Alessia

    2015-01-01

    Mouse models that carry mutations causing thalassemia represent a suitable tool to test in vivo new mutation-specific therapeutic approaches. Transgenic mice carrying the β-globin IVSI-6 mutation (the most frequent in Middle-Eastern regions and recurrent in Italy and Greece) are, at present, not available. We report the production and characterization of a transgenic mouse line (TG-β-IVSI-6) carrying the IVSI-6 thalassemia point mutation within the human β-globin gene. In the TG-β-IVSI-6 mouse (a) the transgenic integration region is located in mouse chromosome 7; (b) the expression of the transgene is tissue specific; (c) as expected, normally spliced human β-globin mRNA is produced, giving rise to β-globin production and formation of a human-mouse tetrameric chimeric hemoglobin (mu) α-globin2/(hu) β-globin2 and, more importantly, (d) the aberrant β-globin-IVSI-6 RNAs are present in blood cells. The TG-β-IVSI-6 mouse reproduces the molecular features of IVSI-6 β-thalassemia and might be used as an in vivo model to characterize the effects of antisense oligodeoxynucleotides targeting the cryptic sites responsible for the generation of aberrantly spliced β-globin RNA sequences, caused by the IVSI-6 mutation. These experiments are expected to be crucial for the development of a personalized therapy for β-thalassemia.

  16. Spatio-temporal Difference of Coupling Coordinative Degree of Ecological Carrying Capacity in the Dongting Lake Region%洞庭湖区生态承载力系统耦合协调度时空分异

    Institute of Scientific and Technical Information of China (English)

    熊建新; 陈端吕; 彭保发; 邓素婷; 谢雪梅

    2014-01-01

    Ecological carrying capacity is a complex dynamic system including natural-economy-society, and its intrinsic coordination is the key to sustainable carrying capacity of ecosystem. In different spatio-temporal scales, the coupling coordinative degree of ecological carrying capacity presents different differences and changes. On the basis of coupling coordinative development interactive mechanism of ecological carrying ca-pacity, the article constructs an evaluation index system of coupling coordinative degree, and analyzes the tem-poral and spatial difference of coupling coordinative degree of ecological carrying capacity in the Dongting Lake region by using capacitive coupling model. The results show that:1) The trends of coupling degree and coupling coordinative degree of ecological carrying capacity in the Dongting Lake region from 2001 to 2012 seemed to be the same, and presented roughly steady upward trend. The mean of coupling degree was 0.499, in antagonistic stage; the mean of coupling coordinative degree was 0.463, in the moderate coupling coordina-tive phase;the average annual growth rate of coupling degree was 3.35%, greater than coupling coordinative degree, which was 3.05%. It indicated that the internal coupling and synergies of the ecological carrying capac-ity was obvious, and the coupling strength was greater than the internal coordination. 2) As to spatial variation, there were three states of coupling degree in three different years in 17 counties of the Dongting Lake area, which were a low coupling, antagonistic phase and running-in phase, each coupling state had different county number and interval change. The coupling coordinative degree appeared three states of low coupling coordina-tion, moderate coupling coordination and highly coupling coordination, the variation was substantially similar to the coupling degree, however the change of the county number and interval change in coordinative state laged behind the coupling degree. The spatial

  17. Could the local population of the Lower Rhine delta supply the Roman army? Part 2: Modelling the carrying capacity of the delta using archaeological, palaeo-ecological and geomorphological data

    NARCIS (Netherlands)

    Kooistra, L.I.; van Dinter, M.; Dütting, M.K.; van Rijn, P.; Cavallo, C.

    2014-01-01

    In this part two of a diptych of articles, we modelled and quantified the carrying capacity of the landscape and the demand and supply of the Roman army in the western Lower Rhine delta with wood and food in the period A.D.  – . The absolute volumes of the wood and food were calculated (in m

  18. Some Mid-Life Ruminations on the Human Capacity to Transcend One's Acculturation.

    Science.gov (United States)

    Rousseve, Ronald J.

    1983-01-01

    The dialectical capacity of human consciousness enables us to generate alternatives in opposition to previous conditioning. Transcending one's acculturation need not leave one searching for gurus. Authentic personal meaning may be attained from an existential reawakening. (RM)

  19. Environmental Carrying Capacity and Its Application in Environmental Impact Assessment of Industrial Park Planning%环境承载力及其在工业园区规划环境影响评价中的应用

    Institute of Scientific and Technical Information of China (English)

    路忠贤; 唐永顺

    2011-01-01

    环境承载力是可持续发展的理论基础,将环境承栽力理论应用到工业园区规划环境影响评价中,对协调区域社会经济发展和资源环境开发利用具有重要的意义。本文基于环境承载力的概念及内涵,在对环境承载力量化分析的基础上,建立一个专门针对工业园区的指标体系,以某工业园区规划环境影响评价为例,分析工业园区各规划期阶段的环境承载力的利用强度,以期为园区的可持续发展提供科学依据。%Environmental carrying capacity is the theoretical tbundation of sustainable development, and applying the theory of environmental carrying capacity to environmental impact assessment of industrial park planning is of great significance in coordinating regional socio - economic development and exploitation and utilization of resources. Based on the concept and connotation of environmental carrying capacity, a specific index system for industrial park is established on the basis of quantitative analysis of environmental carrying capacity. Then, an exmnple for industrial park planning environmental impact assessment was made, and environmental carrying capacity utilizing intensity of industrial park in each planning' stage is analyzed so as to provide scientific basis for sustainable development of industrial parks.

  20. Study on carrying capacity in Liaoning Province marine region by Fuzzy comprehensive evaluation%基于模糊综合评判的辽宁省海域承载力研究

    Institute of Scientific and Technical Information of China (English)

    曹可; 吴佳璐; 狄乾斌

    2012-01-01

    Based on the research results of carrying capacity,the carrying capacity in Liaoning Province marine was assessed by the fuzzy comprehensive evaluation method. The results showed the carrying capacity in Liaoning Province seawater is moderate between 1999 and 2009 except the year 2000. However, the figures always were between 0.34 and 0.40, which meant that the carrying capacity in Liaoning Province seawater was moderate by weak. The factors such as overfishing, large quantities of pollutants into the sea, ecological improvement and marine science and technology all contribute to the state of Liaoning Province seawater. Based on the analysis, the suggestions of improving the carrying capacity in Liaoning Province seawater were brought forward.%借鉴有关承载力的研究成果,利用模糊综合评判方法对辽宁省海域承载力进行了评价分析.结果表明:1999至2009年间,除2000年,辽宁省的海域承载力数值均处于适载范围,但是由于其数值绝大多数都在0.34 ~0.40之间浮动,因此辽宁省的海域承载能力为中等偏弱.过度捕捞、环境污染、环境治理能力和科技发展水平等因素的影响是辽宁省海域承载力中等偏弱的主要因素,基于此提出了改善辽宁省海域承载力的对策建议.

  1. Civil Service Human Resource Capacity and Information Technology

    African Journals Online (AJOL)

    Tesfaye

    2009-01-01

    Jan 1, 2009 ... Abstract. The New Public Management (NPM) model has inspired reforms both in ... employees in Ethiopia and USA, so that the gap analysis between the two countries ... model for analysing the relationship between IT and human resource ... changing the structure of the civil service organisations. More.

  2. Unto Others: Illustrating the Human Capacity for Cooperation

    Science.gov (United States)

    Morris, J. Andrew; Urbanski, John; Hunt, Jason

    2011-01-01

    Research in both evolutionary economics and evolutionary psychology provides strong evidence that human behavior can be, and is, a complex mix of hedonism and altruism with a strong inclination toward cooperation under certain conditions. In this article, behavioral assumptions made in mainstream business theory are compared and contrasted with…

  3. FDI spillovers, absorptive capacities and human capital development

    DEFF Research Database (Denmark)

    Narula, Rajneesh; Marin, Anabel

    2003-01-01

    It is nowadays generally accepted that inward foreign direct investment (FDI) is crucialas a source of technological spillovers. One of the objectives of this paper is to review theevidence on the quantity and quality of human capital employed by domestic and foreignfirms. We examine whether spil...

  4. Prevalence and characterization of plasmids carrying sulfonamide resistance genes among Escherichia coli from pigs, pig carcasses and human

    DEFF Research Database (Denmark)

    Shuyu, Wu; Dalsgaard, A.; Hammerum, A. M.

    2010-01-01

    Background Sulfonamide resistance is very common in Escherichia coli. The aim of this study was to characterize plasmids carrying sulfonamide resistance genes (sul1, sul2 and sul3) in E. coli isolated from pigs and humans with a specific objective to assess the genetic diversity of plasmids...... involved in the mobility of sul genes. Methods A total of 501 E. coli isolates from pig feces, pig carcasses and human stools were tested for their susceptibility to selected antimicrobial. Multiplex PCR was conducted to detect the presence of three sul genes among the sulfonamide-resistant E. coli...... isolates. Fifty-seven sulfonamide-resistant E. coli were selected based on presence of sul resistance genes and subjected to conjugation and/or transformation experiments. S1 nuclease digestion followed by pulsed-field gel electrophoresis was used to visualize and determine the size of plasmids. Plasmids...

  5. Generating a transgenic mouse line stably expressing human MHC surface antigen from a HAC carrying multiple genomic BACs.

    Science.gov (United States)

    Hasegawa, Yoshinori; Ishikura, Tomoyuki; Hasegawa, Takanori; Watanabe, Takashi; Suzuki, Junpei; Nakayama, Manabu; Okamura, Yoshiaki; Okazaki, Tuneko; Koseki, Haruhiko; Ohara, Osamu; Ikeno, Masashi; Masumoto, Hiroshi

    2015-03-01

    The human artificial chromosome (HAC) vector is a promising tool to improve the problematic suppression and position effects of transgene expression frequently seen in transgenic cells and animals produced by conventional plasmid or viral vectors. We generated transgenic mice maintaining a single HAC vector carrying two genomic bacterial artificial chromosomes (BACs) from human HLA-DR loci (DRA and DRB1). Both transgenes on the HAC in transgenic mice exhibited tissue-specific expression in kidney, liver, lung, spleen, lymph node, bone marrow, and thymus cells in RT-PCR analysis. Stable functional expression of a cell surface HLA-DR marker from both transgenes, DRA and DRB1 on the HAC, was detected by flow cytometric analysis of splenocytes and maintained through at least eight filial generations. These results indicate that the de novo HAC system can allow us to manipulate multiple BAC transgenes with coordinated expression as a surface antigen through the generation of transgenic animals.

  6. Individual characterisation of the metastatic capacity of human breast carcinoma.

    Science.gov (United States)

    Heimann, R; Hellman, S

    2000-08-01

    The clinical implications of understanding the invasive and metastatic proclivities of an individual patient's tumour are substantial because the choice of systemic therapy needs to be guided by the likelihood of occult metastasis as well as by knowing when the metastases will become overt. Malignant potential is dynamic, progressing throughout the natural history of a tumour. Required of tumours is the development of critical phenotypic attributes: growth, angiogenesis, invasion and metastagenicity. Characterisation of the extent of tumour progression with regard to these major tumour phenotypes should allow the fashioning of individual therapy for each patient. To examine the clinical parameters and molecularly characterise the metastatic proclivity we have been studying a series of regionally treated breast cancer patients who received no systemic therapy and have long follow-up. Clinically we describe two parameters: metastagenicity - the metastatic proclivity of a tumour, and virulence--the rate at which these metastases appear. Both attributes increase with tumour size and nodal involvement. However, within each clinical group there is a cured population, even in those with extensive nodal involvement, underscoring the heterogeneity of breast cancers within each group and the need for further molecular characterisation. Using biomarkers that characterise the malignant phenotype we have determined that there is progression in the phenotypic changes. Angiogenesis and loss of nm23 are earlier events than the loss of E-cadherin, or abnormalities in TP53. The strongest biomarkers of poor prognosis are p53 and E-cadherin, but even when both are abnormal 42% of node-negative patients are cured indicating that other determinative steps need to occur before successful metastases are established. Identification of these critical later events will further increase the efficacy of determining the malignant capacities of individual tumours.

  7. Neanderthal origin of the haplotypes carrying the functional variant Val92Met in the MC1R in modern humans.

    Science.gov (United States)

    Ding, Qiliang; Hu, Ya; Xu, Shuhua; Wang, Chuan-Chao; Li, Hui; Zhang, Ruyue; Yan, Shi; Wang, Jiucun; Jin, Li

    2014-08-01

    Skin color is one of the most visible and important phenotypes of modern humans. Melanocyte-stimulating hormone and its receptor played an important role in regulating skin color. In this article, we present evidence of Neanderthal introgression encompassing the melanocyte-stimulating hormone receptor gene MC1R. The haplotypes from Neanderthal introgression diverged with the Altai Neanderthal 103.3 ka, which postdates the anatomically modern human-Neanderthal divergence. We further discovered that all of the putative Neanderthal introgressive haplotypes carry the Val92Met variant, a loss-of-function variant in MC1R that is associated with multiple dermatological traits including skin color and photoaging. Frequency of this Neanderthal introgression is low in Europeans (∼5%), moderate in continental East Asians (∼30%), and high in Taiwanese aborigines (60-70%). As the putative Neanderthal introgressive haplotypes carry a loss-of-function variant that could alter the function of MC1R and is associated with multiple traits related to skin color, we speculate that the Neanderthal introgression may have played an important role in the local adaptation of Eurasians to sunlight intensity.

  8. Conditions of Proper Interaction of Low-Pressure Injection Piles (LIP) with Structure and Soil, Carrying Capacity of Pile Anchorage in Foundation

    Science.gov (United States)

    Pachla, Henryk

    2016-12-01

    The formation of a pile in the existing foundation and soil creates a new foundation construction which has a structure of foundation-pile-soil. This construction must be able to transfer loads from the foundation to the pile and from the pile to the soil. The pile structure has to transfer an imposed load. From the point of view of continuum mechanics determination of the capacity of such a system is preceded by the analysis of contact problem of three contact surfaces. Each of these surfaces is determined by different pairs of materials. The pair which creates a pile anchorage is a material from which the foundation is built (structure of stone and grout, brick and grout, concrete or reinforced concrete and grout. The pile structure is formed by grout and steel rebar. The pile formed in soil is created by a pair of grout and soil. What is important is that on contact surfaces the materials adhering to one another are subjected to different deformation types that are controlled by mechanical properties and geometry of these surfaces. In the paper, additional conditions that should be fulfilled for the foundation-pile-soil system to make load transfer from foundation to soil possible and safe are presented. The results of research done by the author on foundation-pile contact surface are discussed. The tests were targeted at verifying the bearing capacity of anchorage and deformation of piles made of grout and other materials from which foundations are built. The specimens were tested in tension and compression. The experiments were conducted on the amount specimens which is regarded as small sample to enable the statistical analysis of the results.

  9. Effects of pole compliance and step frequency on the biomechanics and economy of pole carrying during human walking.

    Science.gov (United States)

    Castillo, Eric R; Lieberman, Graham M; McCarty, Logan S; Lieberman, Daniel E

    2014-09-01

    This study investigates whether a flexible pole can be used as an energy-saving method for humans carrying loads. We model the carrier and pole system as a driven damped harmonic oscillator and predict that the energy expended by the carrier is affected by the compliance of the pole and the ratio between the pole's natural frequency and the carrier's step frequency. We tested the model by measuring oxygen consumption in 16 previously untrained male participants walking on a treadmill at four step frequencies using two loaded poles: one made of bamboo and one of steel. We found that when the bamboo pole was carried at a step frequency 20% greater than its natural frequency, the motions of the centers of mass of the load and carrier were approximately equal in amplitude and opposite in phase, which we predicted would save energy for the carrier. Carrying the steel pole, however, resulted in the carrier and loads oscillating in phase and with roughly equal amplitude. Although participants were less economical using poles than predicted costs using conventional fixed-load techniques (such as backpacks), the bamboo pole was on average 5.0% less costly than the steel pole. When allowed to select their cadence, participants also preferred to carry the bamboo pole at step frequencies of ∼2.0 Hz. This frequency, which is significantly higher than the preferred unloaded step frequency, is most economical. These experiments suggest that pole carriers can intuitively adjust their gaits, or choose poles with appropriate compliance, to increase energetic savings.

  10. Characterization of variant Creutzfeldt-Jakob disease prions in prion protein-humanized mice carrying distinct codon 129 genotypes.

    Science.gov (United States)

    Takeuchi, Atsuko; Kobayashi, Atsushi; Ironside, James W; Mohri, Shirou; Kitamoto, Tetsuyuki

    2013-07-26

    To date, all clinical variant Creutzfeldt-Jakob disease (vCJD) patients are homozygous for methionine at polymorphic codon 129 (129M/M) of the prion protein (PrP) gene. However, the appearance of asymptomatic secondary vCJD infection in individuals with a PRNP codon 129 genotype other than M/M and transmission studies using animal models have raised the concern that all humans might be susceptible to vCJD prions, especially via secondary infection. To reevaluate this possibility and to analyze in detail the transmission properties of vCJD prions to transgenic animals carrying distinct codon 129 genotype, we performed intracerebral inoculation of vCJD prions to humanized knock-in mice carrying all possible codon 129 genotypes (129M/M, 129M/V, or 129V/V). All humanized knock-in mouse lines were susceptible to vCJD infection, although the attack rate gradually decreased from 129M/M to 129M/V and to 129V/V. The amount of PrP deposition including florid/amyloid plaques in the brain also gradually decreased from 129M/M to 129M/V and to 129V/V. The biochemical properties of protease-resistant abnormal PrP in the brain and transmissibility of these humanized mouse-passaged vCJD prions upon subpassage into knock-in mice expressing bovine PrP were not affected by the codon 129 genotype. These results indicate that individuals with the 129V/V genotype may be more susceptible to secondary vCJD infection than expected and may lack the neuropathological characteristics observed in vCJD patients with the 129M/M genotype. Besides the molecular typing of protease-resistant PrP in the brain, transmission studies using knock-in mice carrying bovine PrP may aid the differential diagnosis of secondary vCJD infection, especially in individuals with the 129V/V genotype.

  11. The anti-tumour effect of a DNA vaccine carrying a fusion gene of human VEGFR2 and IL-12

    Directory of Open Access Journals (Sweden)

    Sha Wen

    2016-09-01

    Full Text Available Because of tumour dependence on angiogenesis, anti-angiogenic therapy has become the most attractive area of basic and clinical study in the field of cancer research. In order to create a synergistic effect on angiogenesis and immune regulation, we designed and constructed a new type of DNA vaccine that can express VEGFR2 (vascular endothelial growth factor receptor 2 and the prostate cancer antigen IL-12 (interleukin 12 in the same reading frame. The aim of this study was to investigate the anti-tumour activity of a eukaryotic expression plasmid carrying a fusion gene of human VEGFR2 and IL-12. According to the gene sequences in GenBank, we synthesized the human VEGFR2 and IL-12 genes. VEGFR2 and IL-12 were joined by a sequence encoding a Furin recognition site and a 2A cleavage site, and the resulting fusion gene was cloned into the eukaryotic expression vector pVAX1 to construct the expression plasmid pVAX1-VEGFR2-F2A-IL-12. The expression of VEGFR2 and IL-12 could be detected in 293T cells transfected with pVAX1-VEGFR2-F2A-IL-12 by enzyme-linked immunosorbent assay. Each of these proteins, and in particular co-expression of both proteins, can result in humoral and cellular immune responses in C57BL/6 mice. After injection into the tumour-bearing mouse model, the plasmid showed stronger inhibition of tumour growth than a plasmid expressing VEGFR2 alone. Our results demonstrate that a DNA vaccine carrying a fusion gene of human VEGFR2 and IL-12 could represent a promising approach for tumour immunotherapy.

  12. Marine Carrying Capacity Assessment and Spatio-temporal Analysis in the Bohai Sea Ring Area, China%环渤海地区海域承载力测度与时空分异分析

    Institute of Scientific and Technical Information of China (English)

    孙才志; 于广华; 王泽宇; 刘锴; 刘桂春

    2014-01-01

    The ocean is an important strategic resource in coastal countries and regions. The coastal area has the largest population, the biggest population density, and is the most developed area in China as in other coastal countries. Bohai Sea Ring Area and the Changjiang River Delta, Zhujiang River Delta are the three economic growth poles in China coastal area. With the great growth of economy and society, the contradiction between supply and demand of land resources has become increasingly prominent, marine resources have been predato-ry exploited, marine environment has been seriously polluted. Carrying capacity is an important study on coor-dinating development of resources, environment, and economy. Marine carrying capacity is generally be de-fined as the capacity or limit of the harmonious development of population, environment, and socio-economic that the ocean can carry in a certain period without damaging the sustainable development of marine resource and environment, and ensuring a certain living standard. Marine carrying capacity assessment is of great signif-icance for the sustainable exploitation of marine resources, the environment protection and the coordinated de-velopment of regional economy and society in coastal areas. In this context, evaluation on carrying capacity of Bohai Sea Ring Area is of great significance to the sustainable development of the Bohai Sea economic circle. Since marine resources system has mobility, renewability and other characteristics, marine carrying capacity has openness, dynamics and complexity, it is difficult to accurately quantify the population, environment and socio-economic development or limits that marine carrying capacity can support. But by constructing indicator system, we can measure the dynamic change trend and relative marine carrying capacity then guide the devel-opment of marine economic activities. The fuzzy comprehensive evaluation method is based on the fuzzy math-ematics principle, to analyze and evaluate

  13. Very low cost stand-off suicide bomber detection system using human gait analysis to screen potential bomb carrying individuals

    Science.gov (United States)

    Greneker, Gene, III

    2005-05-01

    Individuals who carry bombs on their bodies and detonate those bombs in public places are a security problem. There is belief that suicide bombings currently used in the mid-east may spread to the United States if the organized terrorist groups operating in the United States are not identified and the cell members arrested. While bombs in vehicles are the primary method currently used to spread terror in Iraq, U. S. warfighters are starting to face suicide bombers. This may become more of the situation if a stand-off detection capability is developed for the vehicle bomb case. This paper presents a concept, that if developed and commercialized, could provide an inexpensive suicide bomber screening system that could be used to screen individuals approaching a checkpoint while the individual is still 500 to 1,000 feet from the checkpoint. The proposed system measures both the radar cross-section of the individual and the radar derived gait characteristics that are associated with individuals carrying a bomb on their body. GTRI researchers propose to use human gait characteristics, as detected by radar, to determine if a human subject who is carrying no visible load on the body is actually carrying a concealed load under their clothes. The use of radar gait as a metric for the detection (as opposed to a video system) of a suicide bomber is being proposed because detection of gait characteristics are thought to be less sensitive to where the bomb is located on the body, lighting conditions, and the fact that the legs may be shrouded in a robe. The detection of a bomb using radar gait analysis may also prove to be less sensitive to changing tactics regarding where the bomb is placed on the body. An inert suicide bomb vest was constructed using water pipes to simulate the explosive devices. Wiring was added to simulated detonators. The vest weighs approximately 35 pounds. Radar data was taken on the volunteer subject wearing the vest that simulated the suicide bomb. This

  14. Muscle mitochondrial capacity exceeds maximal oxygen delivery in humans

    DEFF Research Database (Denmark)

    Boushel, Robert Christopher; Gnaiger, Erich; Calbet, Jose A L

    2011-01-01

    Across a wide range of species and body mass a close matching exists between maximal conductive oxygen delivery and mitochondrial respiratory rate. In this study we investigated in humans how closely in-vivo maximal oxygen consumption (VO(2) max) is matched to state 3 muscle mitochondrial...... respiration. High resolution respirometry was used to quantify mitochondrial respiration from the biopsies of arm and leg muscles while in-vivo arm and leg VO(2) were determined by the Fick method during leg cycling and arm cranking. We hypothesized that muscle mitochondrial respiratory rate exceeds...... that of systemic oxygen delivery. The state 3 mitochondrial respiration of the deltoid muscle (4.3±0.4 mmol o(2)kg(-1) min(-1)) was similar to the in-vivo VO(2) during maximal arm cranking (4.7±0.5 mmol O(2) kg(-1) min(-1)) with 6 kg muscle. In contrast, the mitochondrial state 3 of the quadriceps was 6.9±0.5 mmol...

  15. 基于数学模型的物流港口资源承载能力预测%Forecasting of Resource Carrying Capacity of Logistics Terminals Based on Mathematical Model

    Institute of Scientific and Technical Information of China (English)

    陈朝坚

    2014-01-01

    In this paper, we built the mathematical model of the resource carrying capacity of logistics terminals, then comprehensively forecast the transportation resource carrying capacity of the Qinhuangdao logistics terminal to verify the correctness of the mathematical model and presented the scientific planning for the future construction of the terminal.%建立了物流港口资源承载能力的数学模型,对港口交通资源承载力进行了综合预测预警,以河北省秦皇岛物流港口为例,验证了数学模型的正确性,并对秦皇岛港口未来的港口建设提出了科学的规划。

  16. Agricultural net primary production in relation to that liberated by the extinction of Pleistocene mega-herbivores: an estimate of agricultural carrying capacity?

    Energy Technology Data Exchange (ETDEWEB)

    Doughty, Christopher E; Field, Christopher B, E-mail: chris.doughty@ouce.ox.ac.uk, E-mail: cfield@ciw.edu [Department of Global Ecology, Carnegie Institution, Stanford, CA 94305 (United States)

    2010-10-15

    Mega-fauna (defined as animals > 44 kg) experienced a global extinction with 97 of 150 genera going extinct by {approx} 10 000 years ago. We estimate the net primary production (NPP) that was liberated following the global extinction of these mega-herbivores. We then explore how humans, through agriculture, gradually appropriated this liberated NPP, with specific calculations for 800, 1850, and 2000 AD. By 1850, most of the liberated NPP had been appropriated by people, but NPP was still available in the Western US, South America and Australia. NPP liberated following the extinction of the mega-herbivores was {approx} 2.5% ({approx}1.4 (between 1.2 and 1.6) Pg yr{sup -1} of 56 Pg C yr{sup -1}; Pg: petagrams) of global terrestrial NPP. Liberated NPP peaked during the onset of agriculture and was sufficient for sustaining human agriculture until {approx} 320 (250-500) years ago. Humans currently use {approx} 6 times more NPP than was utilized by the extinct Pleistocene mega-herbivores.

  17. Could the local population of the Lower Rhine delta supply the Roman army? Part 2: Modelling the carrying capacity of the delta using archaeological, palaeo-ecological and geomorphological data

    NARCIS (Netherlands)

    Kooistra, L.I.; van Dinter, M.; Dütting, M.K.; van Rijn, P.; Cavallo, C.

    2014-01-01

    In this part two of a diptych of articles, we modelled and quantified the carrying capacity of the landscape and the demand and supply of the Roman army in the western Lower Rhine delta with wood and food in the period A.D.  – . The absolute volumes of the wood and food were calculated (in m a

  18. Development of Spatial and Verbal Working Memory Capacity in the Human Brain

    Science.gov (United States)

    Thomason, Moriah E.; Race, Elizabeth; Burrows, Brittany; Whitfield-Gabrieli, Susan; Glover, Gary H.; Gabrieli, John D. E.

    2009-01-01

    A core aspect of working memory (WM) is the capacity to maintain goal-relevant information in mind, but little is known about how this capacity develops in the human brain. We compared brain activation, via fMRI, between children (ages 7-12 years) and adults (ages 20-29 years) performing tests of verbal and spatial WM with varying amounts (loads)…

  19. Development of Spatial and Verbal Working Memory Capacity in the Human Brain

    Science.gov (United States)

    Thomason, Moriah E.; Race, Elizabeth; Burrows, Brittany; Whitfield-Gabrieli, Susan; Glover, Gary H.; Gabrieli, John D. E.

    2009-01-01

    A core aspect of working memory (WM) is the capacity to maintain goal-relevant information in mind, but little is known about how this capacity develops in the human brain. We compared brain activation, via fMRI, between children (ages 7-12 years) and adults (ages 20-29 years) performing tests of verbal and spatial WM with varying amounts (loads)…

  20. Research on Forewarning System of Tourism Carrying Capacity in Pingtan Island Based on Fuzzy Comprehensive Evaluation%基于模糊综合评价的海岛旅游环境承载力预警研究

    Institute of Scientific and Technical Information of China (English)

    戴丽芳; 丁丽英

    2012-01-01

    以旅游环境承栽力预警相关理论为指导,采用定性和定量相结合的方法,建立旅游环境承栽力综合评价指标体系,并以平潭海岛为个案进行实证研究.结果表明:平潭旅游环境承栽力总体处于轻度超栽状态,为实现平潭旅游的可持续发展,提出了平潭旅游今后发展的重点方向.%This paper is using the process of qualitative and quantitative combination to build the tourism carrying capacity assessment criteria system under the guidance of the forewarning system of the tourism carrying capacity and based on the empirical research of Pingtan Island. The results show that. the overall tourism carrying capacity in Pingtan is slightly overloaded. In order to achieve the sustainable development of tourism in Pingtan,the paper presents key directions of its furture development.

  1. Water Environmental Carrying Capacity in Shaanxi Province Based on Vector Norm Method%基于向量模法的陕西省水环境承载力评价

    Institute of Scientific and Technical Information of China (English)

    张军

    2012-01-01

    Evaluation index of water environmental carrying capacity in Shaanxi is determined, depending on characteristics of the water environment in Shaanxi Province and selection principles of water environment carrying capacity evaluation index. Vector norm method is used to determined normalized value of each index of the various types of evaluation factors,based on analysis of the vector-mode method characteristics. The study results show that water environmental carrying capacity in Shaanxi Province improved gradually from 2005 to 2009 and the valuation value rose from 0.281 to 0.352.%根据陕西省水环境特征和水环境承载力评价指标的选取原则确定了陕西省水环境承载力评价指标.在分析向量模法特征的基础上,应用向量模法确立了各类评价因素的每个因子的归一化值.得出陕西省水环境承载力状态结果,结果表明2005-2009年间陕西省水环境承载力状况呈逐年改善的趋势,水环境承载力评价值由0.281升至0.352.

  2. Production in Escherichia coli of a rat chimeric proinsulin polypeptide carrying human A and B chains and its preparative chromatography.

    Science.gov (United States)

    Olmos, J; Cruz, N; Sánchez, M; López, M; Balbás, P; Gosset, G; Valle, F; Bolivar, F

    1994-11-30

    A pseudohuman proinsulin coding DNA sequence (MMRPI) carrying human A and B chains, was constructed via directed mutagenesis of a previously modified rat proinsulin cDNA (MRPI) and expressed as a tryptophan (Trp)LE-proinsulin fusion protein in Escherichia coli W3110. Expression of the hybrid gene was achieved by depletion of tryptophan from the medium. The heterologous fusion protein, accumulated as insoluble inclusion bodies within the cell, was obtained by differential centrifugation and then solubilized using formic acid. At the junction of the two peptides, a methionine residue allowed proinsulin to be released from the carrier protein by cyanogen bromide treatment. The sulfonated form of this proinsulin polypeptide was easily purified, at a preparative level, using ion exchange chromatography.

  3. Altered heart rate control in transgenic mice carrying the KCNJ6 gene of the human chromosome 21.

    Science.gov (United States)

    Lignon, Jacques M; Bichler, Zoë; Hivert, Bruno; Gannier, François E; Cosnay, Pierre; del Rio, José A; Migliore-Samour, Danièle; Malécot, Claire O

    2008-04-22

    Congenital heart defects (CHD) are common in Down syndrome (DS, trisomy 21). Recently, cardiac sympathetic-parasympathetic imbalance has also been documented in DS adults free of any CHD. The KCNJ6 gene located on human chromosome 21 encodes for the Kir3.2/GIRK2 protein subunits of G protein-regulated K(+) (K(G)) channels and could contribute to this altered cardiac regulation. To elucidate the role of its overexpression, we used homozygous transgenic (Tg(+/+)) mice carrying copies of human KCNJ6. These mice showed human Kir3.2 mRNA expression in the heart and a 2.5-fold increased translation in the atria. Phenotypic alterations were assessed by recording electrocardiogram of urethane anesthetized mice. Chronotropic responses to direct (carbachol) and indirect (methoxamine) muscarinic stimulation were enhanced in Tg(+/+) mice with respect to wild-type (WT) mice. Alternating periods of slow and fast rhythm induced by CCPA (2-chloro-N-cyclopentyl-adenosine) were amplified in Tg(+/+) mice, resulting in a reduced negative chronotropic effect. These drugs reduced the atrial P wave amplitude and area. P wave variations induced by methoxamine and CCPA were respectively increased and reduced in the Tg(+/+) mice, while PR interval and ventricular wave showed no difference between Tg(+/+) and WT. These results indicate that Tg(+/+) mice incorporating the human KCNJ6 exhibit altered Kir3.2 expression and responses to drugs that would activate K(G) channels. Moreover, these altered expression and responses are limited to sino-atrial node and atria that normally express large amounts of K(G) channels. These data suggest that KCNJ6 could play an important role in altered cardiac regulation in DS patients.

  4. Computing System Construction of Water Environment Carrying Capacity in Huaihe River Basin%淮河流域水环境承载能力计算系统的构建

    Institute of Scientific and Technical Information of China (English)

    严子奇; 夏军; 左其亭; 张永勇

    2009-01-01

    本文介绍了淮河流域水环境承载能力计算系统的总体设计、承载力数学模型的建立、软件系统的结构及应用.研究中通过计算在维系"良好水环境状况"目标下流域所能承载的社会经济规模上限来得到流域水环境承载能力.在耦合了社会经济系统模型、水资源转化关系模型、水环境系统模拟模型的基础上利用数据库、地理信息系统、可视化编程技术将"社会经济-水资源-水环境"系统模型、生态需水量计算模型、以及水环境承载能力计量模型中众多的边界条件、控制条件、可变参数及成果分析进行系统集成.所建立的淮河流域水环境承载能力计算系统可有效地实现流域现状水环境承裁能力的计算以及对未来不同时刻、不同频率来水条件下的承载力进行情景分析计算,为流域水环境承载能力管理提供决策支持.%In this paper, the overall designs and mathematical model of water environment carrying capacity, as well as the system structure and application of water environment carrying capacity computing system in Huaihe River Basin are presented. The carrying capacity of water environment in river basin is reached by calculating the upper limit of the socio-economic scale that watershed can carry under the "good status of water environment". The system is based on an integrated "socio-economic-water resource-water environment" model which is coupled with the socio-economic system model, the water resource transformation relation model and the simulation model of water environment system. The population size is a key indicator to reflect the water environment carrying capacity of the basin, and iterative algorithm is used to get the maximum population size of different water environment carrying capacities. This system also contains a subroutine for ecological water requirement model. The mean value of the results from the Tennant method, base flow method and

  5. 红寺堡生态脆弱移民区水资源承载力分析%An Analysis of Water Resources Carrying Capacity in Vulnerable Ecological Immigration Area in Hongsipu

    Institute of Scientific and Technical Information of China (English)

    贾科利; 郭慧秀

    2015-01-01

    Taking the vulnerable ecological immigration area in Hongsipu as an example, an evaluation indicator system of water resources carrying capacity is constructed from the aspects of water resources system,economic system,social system and ecological system. A comprehensive evaluation and analysis were conducted on the water resources carrying capacity of the area in 2014 and the GDP of the area in 2020 was estimated by the method of non-linear regression and the popula-tion of the area was also estimated by the method of Markov mode. The results showed that the population and economic development are within the carrying capacity of the water resources in Hongsipu district in the present stage and the water resources are not in overloaded state. In 2020,the economic development will be within the carrying capacity of water re-sources,but the population will overload seriously,and the pressure of the water resources carrying capacity will gradually increase.%以红寺堡生态脆弱移民区为例,从社会系统、经济系统、生态系统和水资源系统构建水资源承载力评价指标体系,对该区2014年水资源承载力状况进行综合评价分析,并采用非线性回归法和马尔科夫预测模型分别对该区2020年GDP和人口进行估测。结果表明,现阶段红寺堡区经济、人口总体上可载,水资源未出现超载状态,而到2020年社会经济发展总体可载,但人口超载严重,水资源承载压力逐渐增大。

  6. c-RET molecule in malignant melanoma from oncogenic RET-carrying transgenic mice and human cell lines.

    Directory of Open Access Journals (Sweden)

    Yuichiro Ohshima

    Full Text Available Malignant melanoma is one of the most aggressive cancers and its incidence worldwide has been increasing at a greater rate than that of any other cancer. We previously reported that constitutively activated RFP-RET-carrying transgenic mice (RET-mice spontaneously develop malignant melanoma. In this study, we showed that expression levels of intrinsic c-Ret, glial cell line-derived neurotrophic factor (Gdnf and Gdnf receptor alpha 1 (Gfra1 transcripts in malignant melanomas from RET-transgenic mice were significantly upregulated compared with those in benign melanocytic tumors. These results suggest that not only introduced oncogenic RET but also intrinsic c-Ret/Gdnf are involved in murine melanomagenesis in RET-mice. We then showed that c-RET and GDNF transcript expression levels in human malignant melanoma cell lines (HM3KO and MNT-1 were higher than those in primary cultured normal human epithelial melanocytes (NHEM, while GFRa1 transcript expression levels were comparable among NHEM, HM3KO and MNT-1. We next showed c-RET and GFRa1 protein expression in HM3KO cells and GDNF-mediated increased levels of their phosphorylated c-RET tyrosine kinase and signal transduction molecules (ERK and AKT sited potentially downstream of c-RET. Taken together with the finding of augmented proliferation of HM3KO cells after GDNF stimulation, our results suggest that GDNF-mediated c-RET kinase activation is associated with the pathogenesis of malignant melanoma.

  7. Micro- and Nano-vesicles from First Trimester Human Placentae Carry Flt-1 and Levels Are Increased in Severe Preeclampsia.

    Science.gov (United States)

    Tong, Mancy; Chen, Qi; James, Joanna L; Stone, Peter R; Chamley, Lawrence W

    2017-01-01

    Preeclampsia is a life-threatening hypertensive disease affecting 3-5% of pregnancies. While the pathogenesis of preeclampsia remains unclear, it is known that placenta-derived factors trigger the disease by activating maternal endothelial cells prior to the onset of clinical symptoms. Extracellular vesicles (EVs) of different sizes extruded by the placenta may be one factor. The truncated/secreted form of Flt-1 (sFlt-1) has also been implicated in the pathogenesis of preeclampsia. We investigated whether placental EV production is altered in preeclampsia such that they induce endothelial cell activation, and whether (s)Flt-1 is involved. Macro-, micro-, and nano-vesicles were collected from normal and preeclamptic (PE) placental explants, and separated by differential centrifugation. The number and size of micro- and nano-vesicles was measured by nanoparticle tracking analysis and their ability to activate endothelial cells was quantified by endothelial cell intercellular adhesion molecule 1 expression and monocyte adhesion. The levels of Flt-1 were measured by western blots and ELISA. PE placentae extruded significantly more micro- and nano-vesicles than control placentae and the extruded micro-vesicles were larger than those from control placentae. Micro- and nano-vesicles from both first trimester and term human placentae carried Flt-1 and levels were significantly increased in EVs from severe, but not mild, PE compared to normotensive placentae. All fractions of EVs from PE placentae activated endothelial cells, and for micro- and nano-vesicles, activation was reduced in the presence of exogenous vascular endothelial growth factor (VEGF), a Flt-1 neutralizing antibody, or by pre-treatment with VEGF. While EV-bound VEGF constituted over 20% of the total detected VEGF secreted by PE and normotensive placentae, EV-bound Flt-1 did not significantly contribute to the total level of sFlt-1/Flt-1 released by human third trimester placentae. Micro- and nano

  8. Analysis on Environmental Carrying Capacity in Planning Environmental Impact Assessment of Qunli%群力新区规划环境影响评价中的环境承载力分析

    Institute of Scientific and Technical Information of China (English)

    王博; 付宁

    2012-01-01

    As the core element of planning environmental impact assessment,environmental carrying capacity analysis can characterize the environmental comprehensive impacts of projects from the view of whole system based on the environmental carrying capacity threshold.Its fundamental purpose is to determine whether the project planning suits the bearing capacity of the region's resources.Ultimately,it is to solve the coordinated development of regional socio-economic and environmental resource development issues.Taking the environmental impact assessment of Qunli District as example,this study establishes a comprehensive environmental indicator system and provides detailed description of general content,methods and other aspects of environmental carrying capacity analysis.%环境承载力分析作为规划环境影响评价中核心内容之一,可以在环境承载能力阈值的基础上真实地度量并以系统的观点表达一项规划对环境的综合影响程度,其根本目的在于确定规划开发强度能否与该地区资源环境承载力相协调,归根结底是解决区域社会经济与资源环境协调发展的问题。以群力新区规划环境影响评价为研究实例,建立群力新区的综合环境承载力指标体系,详细地阐述了环境承载力分析的一般内容、方法等方面的内容。

  9. Study on ecological carrying capacity in Shanghai based on sustainable development%基于可持续发展的上海市生态承载力研究

    Institute of Scientific and Technical Information of China (English)

    王瑶

    2016-01-01

    A comprehensive evaluation system of ecological carrying capacity has been constructed from four aspects which include economic development,social progress,energy and resource utilization,en-vironmental quality. Index weights are determined by Coefficient of Variation,the ecological carrying capacity of shanghai from 2003 to 2010 has been calculated by Fuzzy Comprehensive Evaluation. The research shows that:The development of Shanghai shows a good momentum,the sustainable develop-ment capacity is constantly growing,and the ecological carrying capacity is constantly improving,how-ever,the coordination of social declines. We need adjust industrial structure for further,solve urban management issues posed by overpopulation. and improve the degree of social coordination.%从经济发展、社会进步、能源和资源利用、环境质量方面,构建上海市生态承载力评价指标体系,采用变异系数法确定指标权重,运用模糊综合评价法,研究上海市2003~2013年生态承载力.研究表明:上海市经济发展呈现良好态势,可持续发展能力不断增强,生态承载力不断提高,但社会协调度下降,需要进一步调整产业结构,解决人口过多所带来的城市管理问题,提高社会协调度.

  10. Oriented immobilized anti-LDL antibody carrying poly(hydroxyethyl methacrylate) cryogel for cholesterol removal from human plasma

    Energy Technology Data Exchange (ETDEWEB)

    Bereli, Nilay [Department of Chemistry, Hacettepe University, Beytepe, Ankara (Turkey); Sener, Guelsu [Nanotechnology and Nanomedicine Division, Hacettepe University, Ankara (Turkey); Yavuz, Handan, E-mail: handany@hacettepe.edu.tr [Department of Chemistry, Hacettepe University, Beytepe, Ankara (Turkey); Denizli, Adil [Department of Chemistry, Hacettepe University, Beytepe, Ankara (Turkey)

    2011-07-20

    Low density lipoprotein (LDL) cholesterol is a major ingredient of the plaque that collects in the coronary arteries and causes coronary heart diseases. Among the methods used for the extracorporeal elimination of LDL from intravasal volume, immunoaffinity technique using anti-LDL antibody as a ligand offers superior selectivity and specificity. Proper orientation of the immobilized antibody is the main issue in immunoaffinity techniques. In this study, anti-human {beta}-lipoprotein antibody (anti-LDL antibody) molecules were immobilized and oriented through protein A onto poly(2-hydroxyethyl methacrylate) (PHEMA) cryogel in order to remove LDL from hypercholesterolemic human plasma. PHEMA cryogel was prepared by free radical polymerization initiated with N,N,N',N'-tetramethylene diamine (TEMED). PHEMA cryogel with a swelling degree of 8.89 g H{sub 2}O/g and 67% macro-porosity was characterized by swelling studies, scanning electron microscope (SEM) and blood compatibility tests. All the clotting times were increased when compared with control plasma. The maximum immobilized anti-LDL antibody amount was 63.2 mg/g in the case of random antibody immobilization and 19.6 mg/g in the case of oriented antibody immobilization (protein A loading was 57.0 mg/g). Random and oriented anti-LDL antibody immobilized PHEMA cryogels adsorbed 111 and 129 mg LDL/g cryogel from hypercholesterolemic human plasma, respectively. Up to 80% of the adsorbed LDL was desorbed. The adsorption-desorption cycle was repeated 6 times using the same cryogel. There was no significant loss of LDL adsorption capacity. - Research highlights: {yields} LDL cholesterol is a risk factor in the development of coronary heart diseases. {yields} Antibodies against LDL are used for the selective extracorporeal removal of LDL. {yields} Protein A is used for the oriented immobilization of anti LDL onto PHEMA cryogel. {yields} PHEMA cryogels are biocompatible, exhibit a low pressure drop, lack diffusion

  11. Calculation method of livestock carrying capacity of irrigation forage grassland in arid area%干旱区灌溉饲草料地载畜量计算方法

    Institute of Scientific and Technical Information of China (English)

    廖梓龙; 魏永富; 郭中小; 徐晓民; 龙胤慧; 宋一凡

    2014-01-01

    Water is the key factor to in management of grassland and livestock balance in arid area. The effective way of management is to achieve a balance of supply and demand for water forage grass and livestock. This balance consists of three parts:forecasting the forage grass yield by the water balance theory, planning the livestock carrying capacity related to the forage grass intake and drinking water consume, and estimating the optimal number of livestock husbandry under the coupled limitation of the available forage grass intake carrying capacity and the available water resources quantity. There are some inaccuracy problem in applying traditional carrying capacity calculation method, such as the yield forecasting of forage grass and livestock intake feeding. The objective of this paper was to build a new livestock carrying capacity calculation model based on water-grass-livestock balance. Using Damao county in Inner Mongolia Autonomous Region as research area, we analyzed the curve of water productivity under the different rainfall and irrigation conditions, and forecasted the yield of silage corn by water productivity curve. The irrigation experiment of silage corn under different water condition and different precipitation revealed that there was a non-linear relationship between the water productivity and the sum of precipitation and irrigation. Increasing the sum of precipitation and irrigation can promote the water productivity, but excessive supplying from precipitation and irrigation may lead to a reduction of crop water use efficiency. Based on analyzing the curve of water productivity, the experiment result suggested that the highest water productivity was 12.42 kg/m3 water which achieved with 550 mm water from both precipitation and irrigation. Precipitation was the vital limited factor for silage corn yield. The calculated silage corn yield of humid, medium and arid scenario was 6.83 kg/m2, 5.25 kg/m2, 3.47 kg/m2 respectively. For livestock intake feeding

  12. Assessing employability capacities and career adaptability in a sample of human resource professionals

    Directory of Open Access Journals (Sweden)

    Melinde Coetzee

    2015-03-01

    Full Text Available Orientation: Employers have come to recognise graduates’ employability capacities and their ability to adapt to new work demands as important human capital resources for sustaining a competitive business advantage.Research purpose: The study sought (1 to ascertain whether a significant relationship exists between a set of graduate employability capacities and a set of career adaptability capacities and (2 to identify the variables that contributed the most to this relationship.Motivation for the study: Global competitive markets and technological advances are increasingly driving the demand for graduate knowledge and skills in a wide variety of jobs. Contemporary career theory further emphasises career adaptability across the lifespan as a critical skill for career management agency. Despite the apparent importance attached to employees’ employability and career adaptability, there seems to be a general lack of research investigating the association between these constructs.Research approach, design and method: A cross-sectional, quantitative research design approach was followed. Descriptive statistics, Pearson product-moment correlations and canonical correlation analysis were performed to achieve the objective of the study. The participants (N = 196 were employed in professional positions in the human resource field and were predominantly early career black people and women.Main findings: The results indicated positive multivariate relationships between the variables and showed that lifelong learning capacities and problem solving, decision-making and interactive skills contributed the most to explaining the participants’ career confidence, career curiosity and career control.Practical/managerial implications: The study suggests that developing professional graduates’ employability capacities may strengthen their career adaptability. These capacities were shown to explain graduates’ active engagement in career management strategies

  13. Replicon typing of plasmids carrying blaCTX-M-15 among Enterobacteriaceae isolated at the environment, livestock and human interface.

    Science.gov (United States)

    Zurfluh, Katrin; Glier, Melinda; Hächler, Herbert; Stephan, Roger

    2015-07-15

    One of the currently most important antibiotic resistance mechanisms in Enterobacteriaceae is based on the production of ESBL enzymes that inactivate β-lactam antibiotics including cephalosporins and monobactams by hydrolyzing their β-lactam ring. In humans, the most prevalent ESBL enzyme type is encoded by blaCTX-M-15. CTX-M-15 producing enterobacterial strains were also frequently isolated from environmental samples including surface water and freshwater fish. Plasmids, which can be grouped in different plasmid incompatibility types, play a key role in the horizontal spread of these multidrug resistance genes. The purpose of this study was to investigate the diversity of plasmids that carry blaCTX-M-15 genes among Enterobacteriaceae isolated at the environment, livestock and human interface. In total, 81 blaCTX-M-15-harboring isolates collected between 2009 and 2014 were tested for its ability to transfer blaCTX-M-15 by conjugation. These plasmids were further typed. Transfer of a single blaCTX-M-15-harboring plasmid was observed in 32 (39.5%) of the isolates. The most frequent replicon types detected among these plasmids are IncF-type plasmids (n=12) (mostly multi replicon plasmids with a combination of following replicons: IncFII, IncFIA and IncFIB), followed by IncI1 (n=8), IncK (n=3) and IncR (n=1). A noticeable number of plasmids (n=8) could not be assigned to any of the tested replicon types. Knowledge about the plasmid types circulating in bacterial populations is indispensable for understanding epidemiological dynamics and for establishing intervention strategies to stop further dissemination of particular plasmids.

  14. Immunomodulatory capacity of fungal proteins on the cytokine production of human peripheral blood mononuclear cells

    NARCIS (Netherlands)

    Jeurink, P.V.; Lull Noguera, C.; Savelkoul, H.F.J.; Wichers, H.J.

    2008-01-01

    Immunomodulation by fungal compounds can be determined by the capacity of the compounds to influence the cytokine production by human peripheral blood mononuclear cells (hPBMC). These activities include mitogenicity, stimulation and activation of immune effector cells. Eight mushroom strains (Agaric

  15. Building the Capacity to Innovate: The Role of Human Capital--Support Document

    Science.gov (United States)

    Smith, Andrew; Courvisanos, Jerry; Tuck, Jacqueline; McEachern, Steven

    2012-01-01

    This document was produced by the authors based on their research for the report "Building the Capacity to Innovate: The Role of Human Capital," and is an added resource for further information. This document contains the following appendices: (1) Survey methodology; (2) Synopsis of the literature; (3) Interview questions; and (4) Survey…

  16. Mental time travel : A conceptual overview of social psychological perspectives on a fundamental human capacity

    NARCIS (Netherlands)

    Epstude, K.; Peetz, J.

    Humans have the unique capacity to mentally travel through time, that is, to reflect on the past, anticipate the future, and construct alternate realities in their minds. The ability to mentally travel through time affects a variety of social psychological topics. Representations of events can

  17. The Development of Human Capacity in Malawi: The Role of Science and Technology

    Science.gov (United States)

    Nampota, Dorothy; Thompson, Jeff; Wikeley, Felicity

    2009-01-01

    Faced with accelerating poverty, the Malawi government has re-awakened its commitment to the development of human capacity and the role of development in this context. This paper explores the relationship between development and science and technology. It goes on to review the country's science and technology needs and how these justify taking…

  18. Building Human Resources Management Capacity for University Research: The Case at Four Leading Vietnamese Universities

    Science.gov (United States)

    Nguyen, T. L.

    2016-01-01

    At research-intensive universities, building human resources management (HRM) capacity has become a key approach to enhancing a university's research performance. However, despite aspiring to become a research-intensive university, many teaching-intensive universities in developing countries may not have created effective research-promoted HRM…

  19. Low Proliferation and Differentiation Capacities of Adult Hippocampal Stem Cells Correlate with Memory Dysfunction in Humans

    Science.gov (United States)

    Coras, Roland; Siebzehnrubl, Florian A.; Pauli, Elisabeth; Huttner, Hagen B.; Njunting, Marleisje; Kobow, Katja; Villmann, Carmen; Hahnen, Eric; Neuhuber, Winfried; Weigel, Daniel; Buchfelder, Michael; Stefan, Hermann; Beck, Heinz; Steindler, Dennis A.; Blumcke, Ingmar

    2010-01-01

    The hippocampal dentate gyrus maintains its capacity to generate new neurons throughout life. In animal models, hippocampal neurogenesis is increased by cognitive tasks, and experimental ablation of neurogenesis disrupts specific modalities of learning and memory. In humans, the impact of neurogenesis on cognition remains unclear. Here, we…

  20. The Development of Human Capacity in Malawi: The Role of Science and Technology

    Science.gov (United States)

    Nampota, Dorothy; Thompson, Jeff; Wikeley, Felicity

    2009-01-01

    Faced with accelerating poverty, the Malawi government has re-awakened its commitment to the development of human capacity and the role of development in this context. This paper explores the relationship between development and science and technology. It goes on to review the country's science and technology needs and how these justify taking…

  1. Building Human Resources Management Capacity for University Research: The Case at Four Leading Vietnamese Universities

    Science.gov (United States)

    Nguyen, T. L.

    2016-01-01

    At research-intensive universities, building human resources management (HRM) capacity has become a key approach to enhancing a university's research performance. However, despite aspiring to become a research-intensive university, many teaching-intensive universities in developing countries may not have created effective research-promoted HRM…

  2. Mental time travel : A conceptual overview of social psychological perspectives on a fundamental human capacity

    NARCIS (Netherlands)

    Epstude, K.; Peetz, J.

    2012-01-01

    Humans have the unique capacity to mentally travel through time, that is, to reflect on the past, anticipate the future, and construct alternate realities in their minds. The ability to mentally travel through time affects a variety of social psychological topics. Representations of events can diffe

  3. Establishment of transgenic mice carrying the gene of human nuclear receptor NRSA2 (hB1F)

    Institute of Scientific and Technical Information of China (English)

    Shui-Liang Wang; Hua Yang; You-Hua Xie; Yuan Wang; Jian-Zhong Li; Long Wang; Zhu-Gang Wang; Ji-Liang Fu

    2003-01-01

    AIM: Human hepatitis B virus enhancer Ⅱ B1 binding factor (hB1F) was cloned and characterized as a novel member of the Ftz-F1 (NRSA) nuclear receptor subfamily. Although progresses have recently been made, its biological function remains largely unidentified. The aim of this study was to establish an hB1F transgenic mouse model to promote the functional study of hB1F. METHODS: Transgene fragments were microinjected into fertilized eggs of mice. The manipulated embryos were transferred into the oviducts of pseudopregnant female mice.The offsprings were identified by PCR and Southern blot analysis. Transgene expression was analyzed with RT-PCR and Western blot analysis. Transgenic founder mice were used to establish transgenic mouse lineages. The F1 and F2mice were identified by PCR analysis. RESULTS: Seven mice were identified as carrying copies of transgene. RT-PCR and Western blotting results showed that the transgene was expressed in heart, liver, lung, kidney and stomach in one of the transgenic mouse lineages.Genetic analysis of the transgenic mice demonstrated that the transgene was integrated into the chromosome at a single site, and was transmitted stably. CONCLUSION: In this study we established an hB1F transgenic mouse model, which will facilitate the investigation of the biological function of hB1F in vivo.

  4. Ecological Footprint and Ecological Carrying Capacity of Water Resources in Henan Province%河南省水资源生态足迹和生态承载力分析

    Institute of Scientific and Technical Information of China (English)

    卢艳; 于鲁冀; 王燕鹏; 王振波

    2011-01-01

    Previous literatures about ecological footprint and ecological carrying capacity of water resources have little focused on ecological accounting classification of water resources and its equivalence factor and yield factor so that few work on ecological footprint of water resources are satisfactory.Water resources accounting are classified and region equivalence factor and yield factor present in this paper to calculate ecological footprint and ecological carrying capacity of water resources in Henan province by using data in 2007.The results showed that there was an ecological deficit in water resources in most cities of Henan province, but there existed spatial difference not only in ecological footprint and ecological carrying capacity but also in ecological footprint and ecological carrying capacity per capita with great ecological deficit in most of regions.In ecological footprint accounting composition of water resources, ecological footprint of agricultural-forest-fishing was dominant.In ecological capacity accounting composition of water resources,ecological capacity of underground water resource was primary in the south and west of Henan province, but ecological carrying capacity of surface water resource was primary in the north of Henan province.%在水资源生态足迹研究过程中,存在的主要问题是:忽略了对水资源帐户的划分,全球及地区水资源生态均衡因子和产量因子的确定,在实际应用中缺乏对水资源生态足迹和生态承载力的核算.笔者对水资源帐户进行了划分,并计算了地区水资源生态均衡因子和产量因子,以河南省为研究范围核算了2007年水资源生态足迹和生态承载力,结果表明:河南省多数城市水资源呈现生态赤字,同时不仅水资源生态足迹和生态承载力存在着空间差异,而且人均水资源生态足迹和生态承载力也存在着空间分布的不均衡性.水资源生态足迹与生态承载力帐户分解研究结果

  5. Standards for the Estimation of Tourism Carrying Capacity of Countryside Wetland Parks%郊野湿地公园旅游环境容量测算标准构建

    Institute of Scientific and Technical Information of China (English)

    张桦; 储九志

    2013-01-01

    Based on differences among geographic locations, Wetland Parks were divided into 3 types of city, suburban and countryside. A special function of the countryside wetland parks is tourism support. By reviewing the first batch of National Wetland Parks and taking into account of results from relevant studies, an indicators system for the tourism capacity of countryside wetland parks was developed. Standards for estimating the tourism carrying capacity was developed by integrating other relevant standards through questionnaires. The standards covers carrying capacities in 5 major aspects: ecology, resources, psychological, facilities and management capacity, including a total of 18 elements. The standards provided a good foundation for further studies.%基于地理位置差异将湿地公园分为城市、城郊与郊野3类,探讨郊野湿地公园承担旅游功能所具有的特殊性,通过对首批国家湿地公园的梳理,结合相关研究成果,提出郊野湿地公园旅游环境容量测算的指标体系,在此基础上采用相关标准指标,通过问卷调研等方法构建其测算标准.测算标准包括旅游环境容量中的生态、资源、心理、设施及管理5大容量,共计18项因子,为其测算研究提供良好基础.

  6. 重庆市水资源生态足迹与生态承载力分析%Analysis of Water Resources Ecological Footprint and Ecological Carrying Capacity in Chongqing City

    Institute of Scientific and Technical Information of China (English)

    王文国; 龚久平; 青鹏; 潘科; 胡启春

    2011-01-01

    利用水资源生态足迹分析方法对重庆市2000~2009年的水资源生态足迹、生态承载力进行了分析.重庆市历年水资源承载力大于水资源生态足迹,存在一定的生态盈余,水资源生态承载力受干旱等自然灾害影响较大.重庆市水资源生态足迹在逐年提高,万元国内生产总值水资源生态足迹在逐年下降,水资源开发利用程度和利用效率逐步提高.重点讨论了水资源生态足迹在三次产业间和城乡间的差异.%According to the calculation model of water resources ecological footprint, the water resources ecological footprint and ecological carrying capacity in the years from 2000 to 2009 in Chongqing City were analyzed.The results showed that the water resources carrying capacity were more than the water resources ecological footprint in the nine years in Chongqing, the ecological surplus was existed.On the other hand, water resources ecological carrying capacity was impacted by drought.The water resources ecological footprint of Chongqing increased in the pasted nine years,while the water resources ecological footprint per 104 Yuan GDP continued to decrease.This indicated that the utilization of water resources in Chongqing gradually increased in the pasted years.The differences among the primary industry,secondary industry and tertiary industry, and between urban and rural areas in Chongqing City were discussed.

  7. Evaluation of Marine Resource Carrying Capacity in the Construction of Qingdao Blue Economy Zone%青岛市蓝色经济区建设的海洋资源承载力评价

    Institute of Scientific and Technical Information of China (English)

    李京梅; 许玲

    2013-01-01

    From the standpoints of marine resources supply and marine industry demands ,this article built a comprehensive evaluation indicator system and measured marine resource carrying capacity in Qing-dao from 2001 to 2010 by the fuzzy comprehensive evaluation method .The results showed that the devel-opment of marine industry was beyond the marine resource carrying capacity in 2001 to 2006 and 2008 ,and was within the carrying capacity in the rest three years .The construction of the seaports has increased the supply ability of marine resources to some extent ,but the pollution caused by traditional marine industries is still huge ,and is a major cause for the bad performance of marine resource carrying capacity .It is sug-gested that traditional aquaculture should be reformed ,and environment friendly industries like recreation fishery and tourism should be developed in the process of constructing the blue economy zone .%从胶州湾海域资源环境供给和青岛市海洋产业增长需求的角度,构建了青岛市海洋资源承载力综合评价指标体系,利用模糊综合评价方法,对青岛市2001-2010年间海洋资源承载状况进行测度。结果表明,2001-2006年及2008年青岛市海洋资源承载力处于超载状态,其余年份处于适载状态。海岸带开发的港口建设在一定程度上提高了海洋资源的供给能力,但传统海洋产业的排污需求依然较大,是海洋资源承载力超载的重要原因。建议在蓝色经济区建设中,加快对传统养殖业的改造,大力发展休闲渔业、滨海旅游业等能耗低、排污少的产业。

  8. 基于熵权法及灰色关联模型的水资源承载力研究%Research on carrying capacity of water resources based on entropy-weight and grey-correlation model

    Institute of Scientific and Technical Information of China (English)

    朱玲燕; 苏维词

    2014-01-01

    The evaluation of carrying capacity of water resources is an important mean to judge whether the water resources of a city is safe.Taking Quzhou city as the research object , the paper chose the main indexes of carrying capacity evaluation of water resources by grey correlation model.It calculated the total value of water resources carrying capacity and the weight by use of entropy-weight method. Results indi-cate that①the weights of sewage treatment rate and water consumption per ten thousand yuan GDP are 0.1719 and 0.1261 respectively,which are the main indexes of water resources carrying capacity evalua-tion.②The total value of water resources of Quzhou had been raising gradually from 2004 to 2011 .In 2010, the value reached the highest which is about that of 1.23 times in 2004.The paper analyzed the status of water resources in Quzhou and propsed some suggestion for the sustainable utilization of water re-sources.%水资源承载力评价是判断一个城市水资源是否安全的重要手段。本文以衢州市为研究对象,通过应用灰色关联模型选取反映水资源承载力的主要指标,并利用熵权法计算指标权重和水资源承载力综合得分。计算结果表明:①衢州市水资源承载力主要影响指标污水处理率、万元GDP耗水量的权重分别是0.1719,0.1261。②2004-2011年,衢州市水资源承载力综合得分呈上升趋势,特别是2010年达到最高值,约为2004年的1.23倍。本文通过分析衢州市水资源利用状况,提出可持续利用水资源的建议。

  9. Human embryonic stem cells carrying an unbalanced translocation demonstrate impaired differentiation into trophoblasts: an in vitro model of human implantation failure.

    Science.gov (United States)

    Shpiz, A; Kalma, Y; Frumkin, T; Telias, M; Carmon, A; Amit, A; Ben-Yosef, D

    2015-03-01

    Carriers of the balanced translocation t(11;22), the most common reciprocal translocation in humans, are at high risk of creating gametes with unbalanced translocation, leading to repeated miscarriages. Current research models for studying translocated embryos and the biological basis for their implantation failure are limited. The aim of this study was to elucidate whether human embryonic stem cells (hESCs) carrying the unbalanced chromosomal translocation t(11;22) can provide an explanation for repeated miscarriages of unbalanced translocated embryos. Fluorescent in situ hybridization and karyotype analysis were performed to analyze the t(11;22) in embryos during PGD and in the derived hESC line. The hESC line was characterized by RT-PCR and FACS analysis for pluripotent markers. Directed differentiation to trophoblasts was carried out by bone morphogenetic protein 4 (BMP4). Trophoblast development was analyzed by measuring β-hCG secretion, by β-hCG immunostaining and by gene expression of trophoblastic markers. We derived the first hESC line carrying unbalanced t(11;22), which showed the typical morphological and molecular characteristics of a hESC line. Control hESCs differentiated into trophoblasts secreted increasing levels of β-hCG and concomitantly expressed the trophoblast genes, CDX2, TP63, KRT7, ERVW1, CGA, GCM1, KLF4 and PPARG. In contrast, differentiated translocated hESCs displayed reduced and delayed secretion of β-hCG concomitant with impaired expression of the trophoblastic genes. The reduced activation of trophoblastic genes may be responsible for the impaired trophoblastic differentiation in t(11;22)-hESCs, associated with implantation failure in unbalanced t(11;22) embryos. Our t(11;22) hESCs are presented as a valuable human model for studying the mechanisms underlying implantation failure.

  10. Social Carrying Capacity as Status Group Convention.

    Science.gov (United States)

    West, Patrick C.

    A sociological study investigating the relationship between perception of crowding and social status was conducted in a rural camping setting. Results indicate that higher social status groups and groups aspiring to higher social status are more likely to perceive crowding than are lower status groups, but more research is suggested prior to the…

  11. Social Carrying Capacity as Status Group Convention.

    Science.gov (United States)

    West, Patrick C.

    A sociological study investigating the relationship between perception of crowding and social status was conducted in a rural camping setting. Results indicate that higher social status groups and groups aspiring to higher social status are more likely to perceive crowding than are lower status groups, but more research is suggested prior to the…

  12. Ecological Impact and Carrying Capacity of Ponies

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The primary objectives of the study were to determine (1) the grazing patterns of the ponies living within the Chincoteague National Wildlife Refuge, (2) the effects...

  13. 重庆市近10年水资源承载力时空格局动态演变研究%Studies on Spatial and Temporal Evolution of Chongqing Water Ecological Carrying Capacity in Last Ten Years

    Institute of Scientific and Technical Information of China (English)

    张月; 杨华

    2012-01-01

    According to the basic principle and the calculation model of ecological footprint, the spatial patterns and dynamic laws of resources in Chongqing 2000 - 2009 were analyzed. The result showed that water resources per capita ecological footprint and per capita water resources capacity of Chongqing fluctuated in a downward trend. The ecological footprint of water resources fell from 3. 50 hm /person in 2000 to 2. 64 hm /person in 2009. Water resources carrying capacity fell from 6. 05 hm /person in 2000 to 3. 48 hm /person in 2009, and reached the trough period in 2001 and 2006. In the space, the ecological footprint of Chongqing waters resources and water resources carrying capacity showed obviously different spatial distribution. The water resources carrying capacity and ecological footprint of the developed metropolis and the west Chongqing were low. One of the most outstanding was the Yuzhong district. The water ecological footprint and water resources carrying capacity of Three Gorges reservoir and the southeast ecological was relatively high, especially in Chengkou County and Wuxi County. In addition , the 40 districts and counties of Chongqing general water resources ecological footprint was substantially below the carrying capacity of water resources. There were ecological surplus. But some of the districts of water resources ecological deficit were still serious.%以生态足迹理论为基础,通过水资源生态足迹模型研究了重庆市2000 ~ 2009年水资源生态足迹和水资源承载力时空格局动态演变.结果表明,近10年来,重庆市人均水资源生态足迹和人均水资源承载力波动呈下降的趋势,水资源生态足迹从2000年的3.50hm2/人下降到2009年的2.64 hm2/人,水资源承载力从2000年的6.05 hm2/人下降到2009年的3.48 hm2/人,并在2001年和2006年达到低谷期.在空间上,重庆市水资源生态足迹和水资源承载力空间差异较为明显,都市发达经济圈和渝西走廊的水资

  14. An experimental approach to estimation of human information processing capacity for diagnosis tasks in NPPs

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Tae

    2006-02-15

    The objectives of this research are 1) to determine the human's information processing capacity and 2) to describe the relationship between the information processing capacity and human factors. This research centers on the relationship, as experimentally determined, between an operator's mental workload and information flow during accident diagnosis tasks at nuclear power plants (NPPs). The relationship between the information flow rate and operator's mental workload is investigated experimentally. According to this relationship, the operator's information processing capacity can be established. Once the information processing capacity of a main control room (MCR) operator in a NPP is known, it is possible to apply it 1) to predict the operator's performance, 2) to design diagnosis tasks, and 3) to design human-machine interface. In advanced MCR, an operator's mental activity is more important than his or her physical activity. The mental workload is the portion of the operator's limited capacity that is actually required to perform a particular task. A high mental workload may cause an operator to make a mistake and consequently affect that the safe operation of NPPs. Thus, to predict an operator's performance is very important for the nuclear safety. The information processing capacity is the operator's ability to manage the amount of bits per second when an operator is diagnosing tasks or accidents. We can estimate the information processing capacity using the relationship between the information flow rate and human performance. That is, if the operator's performance decreases rapidly as the information flow rate (bit/sec) is increased, it is possible to determine the operator's information processing capacity. A diagnosis task is one of the most complex and mentally demanding tasks as well as a crucial part in maintaining the safe operation of NPPs. Diagnosis tasks refer to the overall tasks of finding the

  15. Cold-preserved human spermatozoa in electrolyte-free solution retain their penetration capacity

    Institute of Scientific and Technical Information of China (English)

    全松; 周海宽; 山野修司; 中坂尚代; 青野敏博

    2003-01-01

    Objective: To evaluate penetration capacity of human sperm preserved in electrolyte-free (EF) solution at 4 ℃.Methods: The motility, acrosomal status penetration rate and fertility index of human sperm were assessed before and after cold-preservation in EF solution, respectively.Results: The motility of human sperm cold-preserved in EF solution for 1 week was significantly higher than that of human sperm cold-preserved in modified human tubal fluid (mHTF) (43.4%±7.9% vs 9.5%±2.5%, P0.05), the percentage of capacitated and acrosome-reacted sperm in the EF solution significantly increased after reinitiation (capacitated sperm: 16.0%±2.3% vs 7.6±1.8%, acrosome-reacted sperm: 9.4%±2.1% vs 3.0%±1.7%, P0.05).Conclusion: Cold-preservation did not induce capacitation and acrosome reaction of human sperm in the EF solution, but human sperm cold-preserved in the EF solution for 1 week possesses as much penetration capacity as fresh sperm.

  16. Gene expression demonstrates an immunological capacity of the human endolymphatic sac

    DEFF Research Database (Denmark)

    Møller, Martin Nue; Kirkeby, Svend; Vikeså, Jonas

    2015-01-01

    OBJECTIVES/HYPOTHESIS: The purpose of the present study is to explore, demonstrate, and describe the expression of genes related to the innate immune system in the human endolymphatic sac. It is hypothesized that the endolymphatic sac has a significant immunological function in the human inner ear....... STUDY DESIGN: DNA microarrays and immunohistochemistry were used for analyses of fresh human endolymphatic-sac tissue samples. METHODS: Twelve tissue samples from the human endolymphatic sac were obtained during translabyrinthine surgery for vestibular schwannoma. Microarray technology was used...... was obtained. Multiple key elements of both the cellular and humoral innate immune system were expressed, including Toll-like receptors 4 and 7, as well as beta-defensin and lactoferrin. CONCLUSIONS: The present data provides the first direct evidence of an immunological capacity of the human endolymphatic sac...

  17. 后发地区生态承载力及其评价方法研究——以海峡西岸经济区为例%Ecological Carrying Capacity and Its Assessment Method in Late-Developing Regions——A Case Study in the Economic Zone on the West Side of the Straits

    Institute of Scientific and Technical Information of China (English)

    赵卫; 沈渭寿; 张慧; 孙明; 孙俊

    2011-01-01

    在区域生态承载力及其与资源、环境承载力相互关系的基础上,针对后发地区敏感的生态环境、强烈的发展愿景和以产业区域转移为主的后发优势战略,阐明了后发地区生态承载力的判定标准和衡量对象,构建了后发地区生态承载力概念模型;与区域生态系统健康评价相结合,运用多目标规划,建立了后发地区生态承载力评价模型,对海峡西岸经济区生态承载力进行了综合评价。目前海西区生态系统所承受的人类干扰总体上较轻,重点产业发展尚未对区域生态系统的结构、功能和健康等级构成威胁。若海西区土地产出率升至2007年上海市土地产出率的75%,海西区及其多数分区生态系统可以持续支撑其重点产业中长期发展。海西区生态系统的承载能力和承载状况具有显著的区域差异,有利于该地区经济社会的健康发展、生态服务功能的持续发挥和区域生态安全的有效保障。%Based on ecological carrying capacity and the relationship between ecological carrying capacity and other carrying capacity,the judgment standard and measurement object of ecological carrying capacity in late-developing regions were defined,the conceptual model of ecological carrying capacity in late-developing regions was also built,according to their sensitive eco-environment,relative slowness of socio-economic development,strong aspiration of development and late-developing strategy.The assessment method of ecological carrying capacity in late-developing regions was also established by multi-objective programming,combining with regional ecosystem health assessment.A case study was carried out in the economic zone on the west side of the Straits(called "Haixi Zone" for short),aiming at the sustainable development of key industry.Results showed that the human disturbance index of Haixi Zone was 2.68% in 2007,which is lower than the average level(3.13%) of China

  18. Building Innovation Capacity: The Role of Human Capital Formation in Enterprises--A Review of the Literature. Occasional Paper

    Science.gov (United States)

    Smith, Andrew; Courvisanos, Jerry; Tuck, Jacqueline; McEachern, Steven

    2011-01-01

    This literature review examines the role of human capital formation in building innovative capacity in firms. The aim of the review is to develop a model of human capital development factors to be used as a basis for a larger research project where the factors that develop innovation capacity in enterprises will be investigated. The review finds…

  19. Auditory capacities in Middle Pleistocene humans from the Sierra de Atapuerca in Spain

    Science.gov (United States)

    Martínez, I.; Rosa, M.; Arsuaga, J.-L.; Jarabo, P.; Quam, R.; Lorenzo, C.; Gracia, A.; Carretero, J.-M.; de Castro, J.-M. Bermúdez; Carbonell, E.

    2004-01-01

    Human hearing differs from that of chimpanzees and most other anthropoids in maintaining a relatively high sensitivity from 2 kHz up to 4 kHz, a region that contains relevant acoustic information in spoken language. Knowledge of the auditory capacities in human fossil ancestors could greatly enhance the understanding of when this human pattern emerged during the course of our evolutionary history. Here we use a comprehensive physical model to analyze the influence of skeletal structures on the acoustic filtering of the outer and middle ears in five fossil human specimens from the Middle Pleistocene site of the Sima de los Huesos in the Sierra de Atapuerca of Spain. Our results show that the skeletal anatomy in these hominids is compatible with a human-like pattern of sound power transmission through the outer and middle ear at frequencies up to 5 kHz, suggesting that they already had auditory capacities similar to those of living humans in this frequency range. PMID:15213327

  20. Auditory capacities in Middle Pleistocene humans from the Sierra de Atapuerca in Spain.

    Science.gov (United States)

    Martínez, I; Rosa, M; Arsuaga, J-L; Jarabo, P; Quam, R; Lorenzo, C; Gracia, A; Carretero, J-M; Bermúdez de Castro, J-M; Carbonell, E

    2004-07-06

    Human hearing differs from that of chimpanzees and most other anthropoids in maintaining a relatively high sensitivity from 2 kHz up to 4 kHz, a region that contains relevant acoustic information in spoken language. Knowledge of the auditory capacities in human fossil ancestors could greatly enhance the understanding of when this human pattern emerged during the course of our evolutionary history. Here we use a comprehensive physical model to analyze the influence of skeletal structures on the acoustic filtering of the outer and middle ears in five fossil human specimens from the Middle Pleistocene site of the Sima de los Huesos in the Sierra de Atapuerca of Spain. Our results show that the skeletal anatomy in these hominids is compatible with a human-like pattern of sound power transmission through the outer and middle ear at frequencies up to 5 kHz, suggesting that they already had auditory capacities similar to those of living humans in this frequency range.

  1. About rats and jackfruit trees: modeling the carrying capacity of a Brazilian Atlantic Forest spiny-rat Trinomys dimidiatus (Günther, 1877) - Rodentia, Echimyidae - population with varying jackfruit tree (Artocarpus heterophyllus L.) abundances.

    Science.gov (United States)

    Mello, J H F; Moulton, T P; Raíces, D S L; Bergallo, H G

    2015-01-01

    We carried out a six-year study aimed at evaluating if and how a Brazilian Atlantic Forest small mammal community responded to the presence of the invasive exotic species Artocarpus heterophyllus, the jackfruit tree. In the surroundings of Vila Dois Rios, Ilha Grande, RJ, 18 grids were established, 10 where the jackfruit tree was present and eight were it was absent. Previous results indicated that the composition and abundance of this small mammal community were altered by the presence and density of A. heterophyllus. One observed effect was the increased population size of the spiny-rat Trinomys dimidiatus within the grids where the jackfruit trees were present. Therefore we decided to create a mathematical model for this species, based on the Verhulst-Pearl logistic equation. Our objectives were i) to calculate the carrying capacity K based on real data of the involved species and the environment; ii) propose and evaluate a mathematical model to estimate the population size of T. dimidiatus based on the monthly seed production of jackfruit tree, Artocarpus heterophyllus and iii) determinate the minimum jackfruit tree seed production to maintain at least two T. dimidiatus individuals in one study grid. Our results indicated that the predicted values by the model for the carrying capacity K were significantly correlated with real data. The best fit was found considering 20~35% energy transfer efficiency between trophic levels. Within the scope of assumed premises, our model showed itself to be an adequate simulator for Trinomys dimidiatus populations where the invasive jackfruit tree is present.

  2. About rats and jackfruit trees: modeling the carrying capacity of a Brazilian Atlantic Forest spiny-rat Trinomys dimidiatus (Günther, 1877 – Rodentia, Echimyidae – population with varying jackfruit tree (Artocarpus heterophyllus L. abundances

    Directory of Open Access Journals (Sweden)

    JHF Mello

    Full Text Available We carried out a six-year study aimed at evaluating if and how a Brazilian Atlantic Forest small mammal community responded to the presence of the invasive exotic species Artocarpus heterophyllus, the jackfruit tree. In the surroundings of Vila Dois Rios, Ilha Grande, RJ, 18 grids were established, 10 where the jackfruit tree was present and eight were it was absent. Previous results indicated that the composition and abundance of this small mammal community were altered by the presence and density of A. heterophyllus. One observed effect was the increased population size of the spiny-rat Trinomys dimidiatus within the grids where the jackfruit trees were present. Therefore we decided to create a mathematical model for this species, based on the Verhulst-Pearl logistic equation. Our objectives were i to calculate the carrying capacity K based on real data of the involved species and the environment; ii propose and evaluate a mathematical model to estimate the population size of T. dimidiatus based on the monthly seed production of jackfruit tree, Artocarpus heterophyllus and iii determinate the minimum jackfruit tree seed production to maintain at least two T. dimidiatus individuals in one study grid. Our results indicated that the predicted values by the model for the carrying capacity K were significantly correlated with real data. The best fit was found considering 20~35% energy transfer efficiency between trophic levels. Within the scope of assumed premises, our model showed itself to be an adequate simulator for Trinomys dimidiatus populations where the invasive jackfruit tree is present.

  3. Testing a measure of organizational learning capacity and readiness for transformational change in human services.

    Science.gov (United States)

    Bess, Kimberly D; Perkins, Douglas D; McCown, Diana L

    2011-01-01

    Transformative organizational change requires organizational learning capacity, which we define in terms of (1) internal and (2) external organizational systems alignment, and promoting a culture of learning, including (3) an emphasis on exploration and information, (4) open communication, (5) staff empowerment, and (6) support for professional development. We shortened and adapted Watkins and Marsick's Dimensions of Learning Organizations Questionnaire into a new 16-item Organizational Learning Capacity Scale (OLCS) geared more toward nonprofit organizations. The OLCS and its subscales measuring each of the above 6 dimensions are unusually reliable for their brevity. ANOVAs for the OLCS and subscales clearly and consistently confirmed extensive participant observations and other qualitative data from four nonprofit human service organizations and one local human service funding organization.

  4. The demonstration projects: creating the capacity for nursing health human resource planning in Ontario's healthcare organizations.

    Science.gov (United States)

    Burkoski, Vanessa; Tepper, Joshua

    2010-05-01

    Timely access to healthcare services requires the right number, mix and distribution of appropriately educated nurses, physicians and other healthcare professionals. In Ontario, as in several other jurisdictions, changing demographics, patterns of health service utilization and an aging workforce have created challenges related to the supply of nurses available now and in the future to deliver quality patient care. From 2006 to 2009, the Nursing Secretariat (NS) of Ontario's Ministry of Health and Long-Term Care (the ministry) undertook a progressive and comprehensive approach to address the issue of nursing supply across the province through the introduction of 17 Nursing Health Human Resources Demonstration Projects (demonstration projects). The demonstration projects initiative has led to the creation of a unique collection of best practices, tools and resources aimed at improving organizational planning capacity. Evaluation of the initiative generated recommendations that may guide the ministry toward policy and program development to foster improved nursing health human resource planning capacity in Ontario healthcare organizations.

  5. Maximal heart rate does not limit cardiovascular capacity in healthy humans

    DEFF Research Database (Denmark)

    Munch, G D W; Svendsen, J H; Damsgaard, R

    2014-01-01

    In humans, maximal aerobic power (VO2 max ) is associated with a plateau in cardiac output (Q), but the mechanisms regulating the interplay between maximal heart rate (HRmax) and stroke volume (SV) are unclear. To evaluate the effect of tachycardia and elevations in HRmax on cardiovascular function...... and capacity during maximal exercise in healthy humans, 12 young male cyclists performed incremental cycling and one-legged knee-extensor exercise (KEE) to exhaustion with and without right atrial pacing to increase HR. During control cycling, Q and leg blood flow increased up to 85% of maximal workload (WLmax...... and RAP (P exercise, suggesting that HRmax and myocardial work capacity do not limit VO2 max in healthy...

  6. Comparison of human pulp tissue dissolution capacities of different irrigating solutions: An in vitro study

    Directory of Open Access Journals (Sweden)

    Atul Jain

    2015-01-01

    Full Text Available Background: Organic tissue dissolution is considered as one of the most important and desirable property of endodontic irrigant, any soft tissue remnant, harboring bacteria, left in the canal after endodontic therapy may be the cause of failure. Aim: The present study aimed at assessing and comparing the human pulp dissolution (thereby eliminating the bacteria capacity of some potential endodontic irrigants viz., sodium hypochlorite (NaOCl (2.5% and 5.25%, chlorine dioxide (5% and peracetic acid (5%. Materials and Methods: Forty human pulp specimens from extracted premolars were taken and weighed. They were immersed in test solution for 30 min, dried on filter paper and weighed again. The percentage weight loss was calculated and statistically analyzed. Conclusion: It can be concluded that NaOCl showed the best tissue dissolution capacity, followed by 5% peracetic acid.

  7. Plasticity in mitochondrial cristae density allows metabolic capacity modulation in human skeletal muscle

    DEFF Research Database (Denmark)

    Nielsen, Joachim; Gejl, Kasper D; Hey-Mogensen, Martin;

    2016-01-01

    that this mechanism allows evasion of the trade-off between cell occupancy by mitochondria and other cellular constituents and improved metabolic capacity and fuel catabolism during prolonged elevated energy requirements. This article is protected by copyright. All rights reserved.......-body level, muscle mitochondrial cristae density is a better predictor of maximal oxygen uptake rate than muscle mitochondrial volume. Our findings establish elevating mitochondrial cristae density as a regulatory mechanism for increasing metabolic power in human skeletal muscle. We propose...

  8. 云南省水资源生态足迹与生态承载力时空动态分析%Analysis of Water Resources Ecological Footprint and Ecological Carrying Capacity in Yunnan Province

    Institute of Scientific and Technical Information of China (English)

    常龙芳; 董金义

    2013-01-01

      应用水资源生态足迹计算模型对云南省近十年及各州(市)近五年水资源生态足迹和生态承载力进行了分析,结果表明:(1)云南省近十年水资源生态足迹变化不明显,而各年份之间的水资源生态承载力差异较大,2001年最高为285×106hm2,2009年最低为175×106hm2.(2)云南省水资源生态足迹较大的区域主要分布于滇中的昆明市和大理市、滇东的曲靖市以及滇东南的红河州,水资源生态足迹均大于2.00×106hm2,而较小的主要分布于滇西北的迪庆州、丽江市和怒江州,均小于1.00×106hm2.%This paper use the calculation model of water resources ecological footprint analyzing the water re-sources ecological footprint and ecological carrying capacity in the past ten years in Yunnan Province and the past five years in all city. The result shows: (1) The water resources ecological footprint in the past ten years is change not obvious in Yunnan province, but the water ecological carrying capacity change is obvious, the water resources ecological carrying capacity in 2001 is the highest for 285 ×106hm2, 2009 is the lowest for 175 × 106hm2. (3) The water resources ecological footprint larger area in Yunnan province mainly distribute in Kun-ming、Dali、Qujing and Honghe, all the water resources ecological footprint are more than 2.00 ×106hm2, and smaller mainly distribute in Diqing、Lijiang and Nujiang, all are less than 1.00×106hm2.

  9. The maximum Sustainable Population Carrying Capacity of Water Resources Evaluation%基于最大可支撑人口水资源承载能力评价分析

    Institute of Scientific and Technical Information of China (English)

    罗铭; 刚傲

    2016-01-01

    In the modernization process of social transformation and development ,one of the important factors which influ-ence and restrict the Beijing -Tianjin - Hebei(BTH)wing area one of reality for the sustainable development is water short-age .This research is quantitative research by the method of carrying population in BTH region water can carry the size of population and economic development .Model validation results show that in the short term ,water quantity of the BTH re-gion population carrying capacity of rich ,can alleviate the contradiction between supply and demand of water resources ;But since the 2025 years ,because the population of the region water resources carrying capacity is insufficient ,the BTH region again go into a period of scarcity .After the implementation of south - to - north water diversion project ,BTH region ob-tained a certain degree of increase ,the water resources carrying capacity in population growth ,however ,under the situation of water resources carrying population are almost limited .Based on this ,the problem of water shortages in exploring the BTH resolution strategy ,not just focus on water saving and water diversion engineering problems ,also need to include for the population growth factors ,avoid excessive increase in population .Otherwise ,the results obtained with water ,is likely to be excessive increase of the population consume ,not really solve the problem of water shortage .%应用“承载人口数”方法定量研究了京、津、冀地区总的水资源所能承载的人口数量与经济发展规模。模型验证结果表明:在短期内,京、津、冀地区的水资源量人口承载能力富足,能缓解水资源供需矛盾;但从2025年后,由于该地区水资源量人口承载能力不足,则京、津、冀地区又重新陷入水资源匮乏时期。南水北调实施以后,京、津、冀地区水资源承载力获得了一定程度的增加,然而在人口增长的态势下,水资

  10. Estimation of Carrying Capacity of Manila Clam (Ruditapesphilippinarum) Culture Pond in Houhai Reclamation Area of Putian city,China%莆田后海垦区菲律宾蛤仔养殖池养殖容量的估算

    Institute of Scientific and Technical Information of China (English)

    杨淑芳; 张磊; 阎希柱

    2016-01-01

    From August 2013 to January 2014,the chlorophyll -a,primary productivity of phytoplankton,clams mortality rate in Houhai reclamation area of Putian were determined.The carrying capacity of the two Manila clam ponds wereestimated by Parsons TR-Takahashi M Ecological Trophodynamicsmodel [P=(BEn )×k]and Tait coastal energy flowing analysis model {B=[(0.1×C)/Q]×k}.Taking into consideration of the unused prima-ry productivity due to the pond effluent,the corrected results of two models were 5.52t and 7.10t for pond 1,with an average of 6.31t;3.60t and 4.62t for pond 2,with an average of 4.11t for two ponds.The actual yields of the two ponds accounted for 59.43%and 97.32%of the estimated capacities respectively.Two ponds of clam mortality rates were 23.43%and 22.5%,respectively.The capacity of pond 1 was significantly larger than that of pond 2.The pos-sible reasons are as follows:chl-a,the shapes of the pond,location and management.The carrying capacity of pond 2 was close to its actual yield.The estimated suitable breeding densities of Manila clam for pond 1 and for pond 2 were 0.61kg/m2 and 0.40kg/m2 respectively.As the actual breeding densities of two ponds are 0.19kg/m2 for each pond. The estimated suitable breeding density of Manila clam calculated from the carrying capacity was larger than the actu-al breeding density.A certain potential to increase the number of breeding clam exists.%2013年8月—2014年2月,对莆田后海垦区菲律宾蛤仔反季节高效生态养殖池叶绿素a、浮游植物初级生产量、蛤仔死亡率等进行了测定,采用ParsonsTR和TakahashiM营养动态模型和Tait沿岸海域能流分析模型对2个菲律宾蛤仔养殖池的养殖容量进行估算,扣除20%的日排水量导致的初级生产量损失,2种估算模型得到的养殖容量经校正后,池1为5.52t、7.1t,平均为6.31t;池2为3.60t、4.62t,平均为4.11t。两个花蛤养殖池的实际产量

  11. The relationship between human skeletal muscle pyruvate dehydrogenase phosphatase activity and muscle aerobic capacity.

    Science.gov (United States)

    Love, Lorenzo K; LeBlanc, Paul J; Inglis, J Greig; Bradley, Nicolette S; Choptiany, Jon; Heigenhauser, George J F; Peters, Sandra J

    2011-08-01

    Pyruvate dehydrogenase (PDH) is a mitochondrial enzyme responsible for regulating the conversion of pyruvate to acetyl-CoA for use in the tricarboxylic acid cycle. PDH is regulated through phosphorylation and inactivation by PDH kinase (PDK) and dephosphorylation and activation by PDH phosphatase (PDP). The effect of endurance training on PDK in humans has been investigated; however, to date no study has examined the effect of endurance training on PDP in humans. Therefore, the purpose of this study was to examine differences in PDP activity and PDP1 protein content in human skeletal muscle across a range of muscle aerobic capacities. This association is important as higher PDP activity and protein content will allow for increased activation of PDH, and carbohydrate oxidation. The main findings of this study were that 1) PDP activity (r(2) = 0.399, P = 0.001) and PDP1 protein expression (r(2) = 0.153, P = 0.039) were positively correlated with citrate synthase (CS) activity as a marker for muscle aerobic capacity; 2) E1α (r(2) = 0.310, P = 0.002) and PDK2 protein (r(2) = 0.229, P =0.012) are positively correlated with muscle CS activity; and 3) although it is the most abundant isoform, PDP1 protein content only explained ∼ 18% of the variance in PDP activity (r(2) = 0.184, P = 0.033). In addition, PDP1 in combination with E1α explained ∼ 38% of the variance in PDP activity (r(2) = 0.383, P = 0.005), suggesting that there may be alternative regulatory mechanisms of this enzyme other than protein content. These data suggest that with higher muscle aerobic capacity (CS activity) there is a greater capacity for carbohydrate oxidation (E1α), in concert with higher potential for PDH activation (PDP activity).

  12. Study of Mechanical Behavior and Ultimate Carrying Capacity of Suspender Anchorage Zone in Axial Direction of Bridge%顺置式吊杆锚固区受力特性与极限承载力研究

    Institute of Scientific and Technical Information of China (English)

    高小妮; 贺拴海; 齐宏学

    2012-01-01

    To have an understanding of the mechanical behavior and ultimate carrying capacity of suspender anchorage zone set in the axial direction of bridge under the action of suspender forces, a combined cable-stayed and self-anchored suspension system bridge that was being constructed was cited as an example, the software ANSYS was used to set up the spatial shell finite element model, the mechanical behavior of the anchorage zone under the action of the worst load was studied, the ultimate carrying capacity of the anchorage zone was analyzed, respectively u-sing the linear elasticity and nonlinearity analysis methods and the force conditions of the components in the anchorage zone were discussed. The results of the study show that under the action of the worst load, the stress in the steel anchor box and steel anchor beam is less than that in the diaphragm. With the exception that the stress concentration in the welding of the steel anchor beam and diaphragm is notable, the stress distribution in all components is uniform and the deformation of the components in the axial direction of the bridge is great. The results of the different analysis methods for the ultimate carrying capacity also show that when the ultimate carrying capacity of such type of the structure is analyzed, using the shell element model, the material nonlinearity should considered only and in the design of the structure, it is proposed that adequate attention should be paid to the problem of insufficient rigidity of the diaphragm.%为掌握顺桥向设置的吊杆锚固区在吊杆力作用下的受力特性和极限承载力,以某在建斜拉—自锚式悬索组合体系桥为依托工程,利用ANSYS软件建立壳单元空间有限元模型,对锚固区在最不利荷载作用下的受力性能进行研究;并分别采用线弹性及非线性分析方法对吊杆锚固区极限承载力进行分析,讨论构件的受力情况.结果表明:在最不利荷载作用下,钢锚箱及钢锚梁

  13. 基于RBF的指标规范值的水资源承载力评价模型%Evaluation Model of Carrying Capacity of Water Resources Represented with Normalized Indices Values Based on Radial Basis Function Neural Network

    Institute of Scientific and Technical Information of China (English)

    臧蕾; 刘伟; 李祚泳

    2012-01-01

    [Objective ] The aim was to study the assessment model of carrying capacity of water resources represented with normalized indices values based on radial basis function network ( RBF). [ Method] On the basis of the normalized transformation for indices, the basis function of model was universal for various indices and made representative calculation greatly simplified, as mean as normalized values of standards at all levels as the normalized values of each component of center vector for the basis functions in hidden nodes. [ Result] The RBF model optimized weight values by monkey king algorithm was applied to assess the carrying capacities of water resources in three districts of Changwu County of Shaanxi Province, the evaluation results were basically consistent with that of fuzzy assessment method. [ Conclusion] RBF model is simple and practical, and has universality and generality.%[目的]研究基于指标规范值的区域水资源承载力评价的径向基函数网络模型(RBF).[方法]在对指标进行规范变换的基础上,将指标各级标准规范值的平均值作为RBF的隐层节点基函数中心矢量各分量的规范值,因而基函数对各指标具有普适性,使基函数的表示和计算大为简化.[结果]将猴王算法优化网络权值得到的RBF模型应用于陕西省长武县3个区域水资源承载力的评价,其评价结果与模糊综合评价结果基本一致.[结论]RBF模型具有简单、实用的特点,具有普适性和通用性.

  14. 基于RBF的指标规范值的水资源承载力评价模型(英文)%Evaluation Model of Carrying Capacity of Water Resources Based on Standardized Indices of Radial Basis Function

    Institute of Scientific and Technical Information of China (English)

    臧蕾; 李祚泳; 刘伟

    2012-01-01

    [目的]研究基于指标规范值的区域水资源承载力评价的径向基函数网络模型(RBF)。[方法]在对指标进行规范变换的基础上,将指标各级标准规范值的平均值作为RBF的隐层节点基函数中心矢量各分量的规范值,因而基函数对各指标具有普适性,使基函数的表示和计算大为简化。[结果]将猴王算法优化网络权值得到的RBF模型应用于陕西省长武县3个区域水资源承载力的评价,其评价结果与模糊综合评价结果基本一致。[结论]RBF模型具有简单、实用的特点,具有普适性和通用性。%[Objective] The aim was to study on RBF model about evaluation on carrying capacity of water resources based on standardized indices. [Method] The indices were transformed and the averages of standard values in different levels were taken as the standardized values of components of central vectors for basic functions of RBF hidden nodes. Hence, the basic functions are suitable for most indices, simplifying expression and calculation of basic functions. [Result] RBF models concluded through Monkey-king Genetic Algorithm with weights optimization are used in evaluation on water carrying capacity in three districts in Changwu County in Shaanxi Province, which were in consistent with that through fuzzy evaluation. [Conclusion] RBF, simple and practical, is universal and popular.

  15. Human telomeres that carry an integrated copy of human herpesvirus 6 are often short and unstable, facilitating release of the viral genome from the chromosome.

    Science.gov (United States)

    Huang, Yan; Hidalgo-Bravo, Alberto; Zhang, Enjie; Cotton, Victoria E; Mendez-Bermudez, Aaron; Wig, Gunjan; Medina-Calzada, Zahara; Neumann, Rita; Jeffreys, Alec J; Winney, Bruce; Wilson, James F; Clark, Duncan A; Dyer, Martin J; Royle, Nicola J

    2014-01-01

    Linear chromosomes are stabilized by telomeres, but the presence of short dysfunctional telomeres triggers cellular senescence in human somatic tissues, thus contributing to ageing. Approximately 1% of the population inherits a chromosomally integrated copy of human herpesvirus 6 (CI-HHV-6), but the consequences of integration for the virus and for the telomere with the insertion are unknown. Here we show that the telomere on the distal end of the integrated virus is frequently the shortest measured in somatic cells but not the germline. The telomere carrying the CI-HHV-6 is also prone to truncations that result in the formation of a short telomere at a novel location within the viral genome. We detected extra-chromosomal circular HHV-6 molecules, some surprisingly comprising the entire viral genome with a single fully reconstituted direct repeat region (DR) with both terminal cleavage and packaging elements (PAC1 and PAC2). Truncated CI-HHV-6 and extra-chromosomal circular molecules are likely reciprocal products that arise through excision of a telomere-loop (t-loop) formed within the CI-HHV-6 genome. In summary, we show that the CI-HHV-6 genome disrupts stability of the associated telomere and this facilitates the release of viral sequences as circular molecules, some of which have the potential to become fully functioning viruses.

  16. Evaluation of Land Resources Carrying Capacity in Panjin City Based on Remote Sensing%基于遥感影像的盘锦市土地资源承载力评价研究

    Institute of Scientific and Technical Information of China (English)

    任家强; 席秋红; 王婷

    2014-01-01

    本文以盘锦市作为研究区,通过对盘锦市2000年、2004年和2010年三个时间段的Landsat TM遥感影像处理,获取盘锦市2000年、2004年和2010年的土地利用数据,并综合考虑人口-资源-环境之间的协调发展,构建了盘锦市土地承载力评价体系,运用层次分析法及多因素加权求和法,对盘锦市土地资源承载力进行评价研究。%Taking Panjin City as study area, through the 2000, 2004 and 2010 Landsat TM remote sensing image, the land use data of 2000, 2004 and 2010 were obtain .Considering the coor-dinated development between the population-resources-environ-ment, build the PanJin City land Resources Carrying Capacity evaluation system, using the analytic hierarchy process (AHP) and multifactor weighted summation method, to evaluate PanJinShi bearing capacity of land resources research.

  17. Vitamins, fatty acids, and antioxidant capacity stability during storage of freeze-dried human milk.

    Science.gov (United States)

    Lozano, Blanca; Castellote, Ana Isabel; Montes, Rosa; López-Sabater, M Carmen

    2014-09-01

    Although freezing is the most common method used to preserve human milk, nutritional and immunological components may be lost during storage. Freeze-drying could increase the shelf life of human milk, while preserving its original characteristics. Seventy-two samples of freeze-dried human milk were stored for different periods of time, up to a maximum of 3 months, at 4 °C or 40 °C. Vitamin C, tocopherols, antioxidant capacity, and fatty acids composition were analyzed. A new HILIC-UHPLC method improving vitamin C determination was also validated. Ascorbic acid and total vitamin C concentrations significantly decreased at both temperatures, while antioxidant capacity only decreased at 40 °C. Fatty acids composition and both γ-tocopherol and δ-tocopherol contents remained unaltered. The stability after storage of freeze-dried milk was higher than that reported for frozen or fresh milk indicating that freeze-drying is a promising option to improve the preservation of human milk in banks.

  18. The Influence of Probiotic Lactobacillus casei in Combination with Prebiotic Inulin on the Antioxidant Capacity of Human Plasma.

    Science.gov (United States)

    Kleniewska, Paulina; Hoffmann, Arkadiusz; Pniewska, Ewa; Pawliczak, Rafał

    2016-01-01

    The aim of the present study was to assess whether probiotic bacteria Lactobacillus casei (4 × 10(8) CFU) influences the antioxidant properties of human plasma when combined with prebiotic Inulin (400 mg). Experiments were carried out on healthy volunteers (n = 32). Volunteers were divided according to sex (16 male and 16 female) and randomly assigned to synbiotic and control groups. Blood samples were collected before synbiotic supplementation and after 7 weeks, at the end of the study. Catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) activity, and the ferric reducing ability of plasma (FRAP) in human plasma were examined. The administration of synbiotics containing L. casei plus Inulin resulted in a significant increase in FRAP values (p = 0.00008) and CAT activity (p = 0.02) and an insignificant increase in SOD and GPx activity compared to controls. Synbiotics containing L. casei (4 × 10(8) CFU) with prebiotic Inulin (400 mg) may have a positive influence on human plasma antioxidant capacity and the activity of selected antioxidant enzymes.

  19. [Nuclear heterogeneity and proliferative capacity of human adipose derived MSC-like cells].

    Science.gov (United States)

    Lavrov, A V; Smirnichina, S A

    2010-01-01

    Adipose derived stem cells (ADSCs) are MSC-like cells which could be easily used for regenerative medicine. Here, the morphology and proliferative capacity of human ADSCs is discribed. ADSCs were analyzed after one month of cultivation at a density of 10 cells/cm2. 21 colonies were counted. Few atypical cells (huge nuclei and cytoplasm) were found in 9 out of 17 colonies analyzed. ANOVA demonstrated that colonies also differed (P = 0.0025) in nuclei dimensions and scatter in the dimensions in each colony. Nuclei dimensions and cell density logarithms correlated in reverse proportion (-0.7; P = 0.002). Thus, ADSCs were heterogeneous and represented two types of cells: small highly proliferative and large low proliferative cells. Cell heterogeneity observed in some colonies might be due to cells registered at different cell cycle phases. Stable and typical morphology, colony-formation capability and high proliferative capacity of cells indicate visceral adipose tissue as a rich source of ADSCs.

  20. Detection of mcr-1-Carrying Escherichia coli Causing Bloodstream Infection in a New York City Hospital: Avian Origins, Human Concerns?

    Science.gov (United States)

    Macesic, Nenad; Green, Daniel; Wang, Zheng; Sullivan, Sean B; Shim, Kevin; Park, Sarah; Whittier, Susan; Furuya, E Yoko; Gomez-Simmonds, Angela; Uhlemann, Anne-Catrin

    2017-01-01

    The spread of mcr-1 in the United States remains poorly defined. mcr-1-producing Escherichia coli that also carried blaSHV-12 was detected in a hospitalized patient. No additional cases were identified during screening of 801 Gram-negative isolates. Genomic sequencing identified an IncX4 mcr-1- harboring plasmid and ST117 clonal background associated with avian pathogenic E coli.

  1. Assessment of Human DNA Repair (NER) Capacity With DNA Repair Rate (DRR) by Comet Assay

    Institute of Scientific and Technical Information of China (English)

    WEI ZHENG; JI-LIANG HE; LI-FEN JIN; JIAN-LIN LOU; BAO-HONG WANG

    2005-01-01

    Objective Alkaline comet assay was used to evaluate DNA repair (nucleotide excision repair, NER) capacity of human fresh lymphocytes from 12 young healthy non-smokers (6 males and 6 females). Methods Lymphocytes were exposed to UV-C (254 nm) at the dose rate of 1.5 J/m2/sec. Novobiocin (NOV) and aphidicolin (APC), DNA repair inhibitors, were utilized to imitate the deficiency of DNA repair capacity at the incision and ligation steps of NER. Lymphocytes from each donor were divided into three grougs: UVC group, UVC plus NOV group, and UVC plus APC group. DNA single strand breaks were detected in UVC irradiated cells incubated for 0, 30, 60, 90, 120, 180, and 240 min after UVC irradiation. DNA repair rate (DRR) served as an indicator of DNA repair capacity. Results The results indicated that the maximum DNA damage (i.e. maximum tail length) in the UVC group mainly appeared at 90 min. The ranges of DRRs in the UVC group were 62.84%-98.71%. Average DRR value was 81.84%. The DRR difference between males and females was not significant (P<0.05). However, the average DRR value in the UVC plus NOV group and the UVC plus APC group was 52.98% and 39.57% respectively, which were significantly lower than that in the UVC group (P<0.01). Conclusion The comet assay is a rapid, simple and sensitive screening test to assess individual DNA repair (NER) capacity. It is suggested that the time to detect DNA single strand breaks in comet assay should include 0 (before UV irradiation), 90 and 240 min after exposure to 1.5 J·m-2 UVC at least. The DRR, as an indicator, can represent the individual DNA repair capacity in comet assay.

  2. Incorporación de la cobertura de escape en un modelo de capacidad de carga para venado de cola blanca Incorporation of escape cover in a model to estimate carrying capacity for white-tailed deer

    Directory of Open Access Journals (Sweden)

    FX Plata

    2013-01-01

    Full Text Available Los objetivos de este trabajo fueron evaluar la incorporación de la cobertura de escape en un modelo de capacidad de carga (K de venado cola banca, evaluar el modelo por análisis de sensibilidad y comparar la estimación de la K con el modelo versus un modelo basado en disponibilidad de nutrientes. El trabajo se desarrolló en la localidad de Santa Cruz Nuevo, Puebla, México, en un área de 50 km², donde se establecieron 13 transectos de 800 m de longitud por 6 de ancho y se colectó información para establecer la relación entre la cobertura de escape y la presencia de indicios de venado mediante regresión lineal. Dicha relación se incorporó en un modelo de estimación de K, después de lo cual se realizó un análisis de sensibilidad del mismo. Los indicios animales se observaron principalmente en las áreas con una cobertura de escape mayor al 59% y se distribuyeron en una forma cuadrática hasta llegar al 100%. El análisis de sensibilidad mostró que la cobertura de escape y la vegetación arbustiva fueron los principales componentes para aumentar la capacidad de carga, mientras que el peso vivo del venado para disminuirla.The objective of this study was to establish the incorporation of escape cover in a carrying capacity (K model for white-tailed deer (Odocoileus virginianus. The study was carried out in Santa Cruz Nuevo, Puebla, Mexico in an area of 50 Km². The information was gathered through 13 transects of 800 by six m. The information served to establish the relationship between the escape cover and the faecal pellets of deer using a linear regression analysis. The relationship was included in a model for estimation of K, then a sensibility analysis was conducted. Faecal pellets were found in areas with an escape cover bigger than 59% and they were distributed in a cubic arrangement until reaching the 100%. The sensibility analysis showed that the escape cover and the brush vegetation were the main components to increase the

  3. Development of Grain Production and Spatial Pattern of Land Carrying Capacity in Chongqing City%重庆市粮食生产发展特征及土地资源承载力空间格局研究

    Institute of Scientific and Technical Information of China (English)

    施开放; 刁承泰

    2012-01-01

    首先分析了1985—2010年重庆市粮食生产发展过程的特点,随后以人粮关系为基础,构建了土地资源承载力(LCC)模型和土地资源承载指数(LCCI)模型,从区县尺度对重庆市土地资源承载力空间格局现状进行了分析。结果表明:1985—2010年重庆市粮食生产呈周期性波动特征,具有明显的不稳定性;人均粮食占有量起伏较小,基本维持在356.5kg/人左右,人口增幅略小于粮食产量增幅。2009年重庆市区县土地资源承载力主要以人口超载、粮食短缺为主要特征。都市发达经济圈的8个区县以及渝东北翼的大部分区县表现为粮食亏缺、人口超载,渝东南翼的大部分区县以及渝西的大部分区县表现为人粮均衡,只有合川区、南川区、黔江区、石柱县和秀山县5个区县处于粮食盈余状态。因此必须加强重庆各区县以及重庆市与其他省市之间的粮食贸易和调配来满足人口超载区的粮食需求。%With the growth of population,land carrying capacity and food safety have attracted great attention worldwide.In this study,the characteristics of development of grain production in Chongqing City were analyzed and summarized firstly,and then,land carrying capacity(LCC) and land carrying capacity index(LCCI) models were developed from the point of man-grain relationship.Finally,the LCCI was calculated for each county of Chongqing in 2009,and the current situation of land carrying capacity and its spatial pattern were systematically evaluated.The results showed that: from 1985 to 2010,the grain production of Chongqing City presented an upward tendency and the population growth rate was less than that of grain yield,and the grain yield per capita kept stable;food deficits and population overloading remained the primary characteristics of LCC of Chongqing City at a county scale in 2009.The 8 counties of Metropolitan Developed Circle and the counties of Northeast of

  4. MSCA-1/TNAP selection of human jaw periosteal cells improves their mineralization capacity.

    Science.gov (United States)

    Alexander, Dorothea; Schäfer, Fabian; Olbrich, Marcus; Friedrich, Björn; Bühring, Hans-Jörg; Hoffmann, Jürgen; Reinert, Siegmar

    2010-01-01

    Human jaw periosteum-derived cells (JPCs) represent an alternative cell source to bone marrow-derived mesenchymal stem cells for tissue engineering applications in the oral and maxillofacial surgery. In this study we investigated how far the presence or expression of human mesenchymal stem cell antigen-1/tissue non-specific alkaline phosphatase (MSCA-1/TNAP) and LNGFR (CD271) can be utilized to select and enrich the osteogenic progenitor cell fraction from the entire JPC population. Depending on their mineralization capacity, we classified the human isolated JPCs into mineralizing (mJPCs) and non-mineralizing JPCs (nmJPCs). Flow cytometric analyses revealed that undifferentiated mJPCs expressed MSCA-1/TNAP at significant higher levels than nmJPCs at day 5 and 10 of osteogenesis. Western blot analyses showed increased MSCA-1/TNAP expression levels in mJPCs during osteogenesis, whereas in nmJPCs MSCA-1/TNAP expression remained undetectable. Using the MSCA-1 and LNGFR specific antibodies, we separated the positive and negative fractions from the entire mJPC population. In order to analyse the mineralization capacity of the MSCA-1(+) and LNGFR(+) cell subsets, we quantified the calcium deposition in both subpopulations in comparison to the respective negative subpopulations. The MSCA-1(+)/TNAP(+) cell fraction showed a significant higher osteogenic capacity compared to the MSCA-1-/TNAP- cell fraction whereas the LNGFR(+/-) cell fractions did not differ in their osteogenic potential. Our findings suggest that MSCA-1 may represent a promising osteogenic marker for mJPC.

  5. DNA ligase III and DNA ligase IV carry out genetically distinct forms of end joining in human somatic cells.

    Science.gov (United States)

    Oh, Sehyun; Harvey, Adam; Zimbric, Jacob; Wang, Yongbao; Nguyen, Thanh; Jackson, Pauline J; Hendrickson, Eric A

    2014-09-01

    Ku-dependent C-NHEJ (classic non-homologous end joining) is the primary DNA EJing (end joining) repair pathway in mammals. Recently, an additional EJing repair pathway (A-NHEJ; alternative-NHEJ) has been described. Currently, the mechanism of A-NHEJ is obscure although a dependency on LIGIII (DNA ligase III) is often implicated. To test the requirement for LIGIII in A-NHEJ we constructed a LIGIII conditionally-null human cell line using gene targeting. Nuclear EJing activity appeared unaffected by a deficiency in LIGIII as, surprisingly, so were random gene targeting integration events. In contrast, LIGIII was required for mitochondrial function and this defined the gene's essential activity. Human Ku:LIGIII and Ku:LIGIV (DNA ligase IV) double knockout cell lines, however, demonstrated that LIGIII is required for the enhanced A-NHEJ activity that is observed in Ku-deficient cells. Most unexpectedly, however, the majority of EJing events remained LIGIV-dependent. In conclusion, although human LIGIII has an essential function in mitochondrial maintenance, it is dispensable for most types of nuclear DSB repair, except for the A-NHEJ events that are normally suppressed by Ku. Moreover, we describe that a robust Ku-independent, LIGIV-dependent repair pathway exists in human somatic cells.

  6. Increased nicotine response in iPSC-derived human neurons carrying the CHRNA5 N398 allele

    Science.gov (United States)

    Oni, Eileen N.; Halikere, Apoorva; Li, Guohui; Toro-Ramos, Alana J.; Swerdel, Mavis R.; Verpeut, Jessica L.; Moore, Jennifer C.; Bello, Nicholas T.; Bierut, Laura J.; Goate, Alison; Tischfield, Jay A.; Pang, Zhiping P.; Hart, Ronald P.

    2016-01-01

    Genetic variation in nicotinic receptor alpha 5 (CHRNA5) has been associated with increased risk of addiction-associated phenotypes in humans yet little is known the underlying neural basis. Induced pluripotent stem cells (iPSCs) were derived from donors homozygous for either the major (D398) or the minor (N398) allele of the nonsynonymous single nucleotide polymorphism (SNP), rs16969968, in CHRNA5. To understand the impact of these nicotinic receptor variants in humans, we differentiated these iPSCs to dopamine (DA) or glutamatergic neurons and then tested their functional properties and response to nicotine. Results show that N398 variant human DA neurons differentially express genes associated with ligand receptor interaction and synaptic function. While both variants exhibited physiological properties consistent with mature neuronal function, the N398 neuronal population responded more actively with an increased excitatory postsynaptic current response upon the application of nicotine in both DA and glutamatergic neurons. Glutamatergic N398 neurons responded to lower nicotine doses (0.1 μM) with greater frequency and amplitude but they also exhibited rapid desensitization, consistent with previous analyses of N398-associated nicotinic receptor function. This study offers a proof-of-principle for utilizing human neurons to study gene variants contribution to addiction. PMID:27698409

  7. Lithuanian reform on legal capacity: from soviet context towards the modern human rigths standards

    Directory of Open Access Journals (Sweden)

    Dovilė

    2015-12-01

    Full Text Available All human beings are born free and equal in dignity and rights. This is a basic fundamental principal upon which all the international law is based. Consequently people with mental disabilities too, are entitled to the enjoyment of the same human rights, in equal measure, as all other people. New international human rights treaties and documents are adopted in order to strengthen security and realisation of the rights of most vulnerable groups of people. UN Convention on the rights of persons with disabilities (CRPD is one of the newest UN’s legally binding instruments, adopted by UN General Assembley in 2006, with its purpose to “promote, protect and ensure the full and equal enjoyment of all human rights and fundamental freedoms by all persons with disabilities, and to promote respect for their inherent dignity”. The Convention bringing about a paradigm shift in attitudes of persons with disabilities as “subjects” of all human rights and basis for their protection. One of the most substantive areas that demonstrates major ‘paradigm shift’ of CRPD is provision of equality before the law to all the persons with disabilities. The right to recognition everywhere as persons before the law puts an end to various practices of the removal of rights of persons depending on their health, disability status. After the ratification of CRPD on 27 May, 2010, currently Lithuania has all legal obligations under CRPD, including the provisions on the equality before the law As in majority of other Eastern European region countries, both full guardianship and partial guardianship (curatorship meant to safeguard the human rights of vulnerable people lacking capacity existed in Lithuania for decades. Recently reform of this legal institute in order to adhere to the international human rights standards and respect the principals of disabled people human rights protection and nondiscrimination. There is no one state up to now with the developed ideal

  8. 四川省水资源生态足迹与生态承载力的时空分析%Analysis of Spatio-Temporal Characteristics of Water Resources Ecological Footprint and Ecological Carrying Capacity in Sichuan Province

    Institute of Scientific and Technical Information of China (English)

    王文国; 何明雄; 潘科; 祝其丽; 周芸; 樊毅; 胡启春

    2011-01-01

    According to the basic principle and calculation model of water resources ecological footprint,the water resources ecological footprint and ecological carrying capacity in the years from 2001 to 2009 in Sichuan Province were analyzed.The results showed that the water resources ecological footprint per capita of Sichuan Province increased in the past nine years,while the water resources ecological footprint per 104 yuan GDP in Sichuan Province continued to decrease.This indicated that the utilization of water resources in Sichuan Province gradually increased in the past years.On the other hand,water resources ecological carrying capacity was impacted by drought,however,the ecological carrying capacity of water resources in Sichuan Province was more than the ecological footprint,the ecological surplus was existed.That is to say that the sustainable utilization of water resources in Sichuan Province was well.But the water resources in Sichuan were unevenly distributed.The economically backward western Sichuan where water resources are less demanded was rich in water resources and had large ecological surplus.On the contrary,the economically more developed eastern Sichuan where water resources are highly demanded was short in water resources and had small ecological surplus.Even in the cities of Mianyang,Suining,Neijiang and Zigong the ecological deficit appeared,showing a state of insecurity on utilization of water resources.The changes of ecological footprint of water resources were closely related to socio-economic development;it should fully considered the spatial-temporal distribution of water resources in Sichuan Province,adjusting the industrial structure,rational ma-nagement and use of water resources,promoted the sustainable development of the overall socio-economy of Sichuan Province.%根据水资源生态足迹的基本原理和计算模型,对四川省2001—2009年水资源生态足迹、生态承载力进行分析。结果表明,在2001—2009年间四

  9. Water resources carrying capacity of Xianyang City based on system dynamics%基于系统动力学的咸阳市水资源承载力

    Institute of Scientific and Technical Information of China (English)

    黄蕊; 刘俊民; 李燐楷

    2012-01-01

    Based on the principles and methods of system dynamics, carrying capacity of water resources system of Xianyang City is divided into industrial, agricultural, life and ecology, water and wastewater treatment and reuse subsystem. Regarding water shortage level as the main feedback factor, considering people "s decision-making preferences of using water when water is in shortage, a system dynamics model of water resources carrying capacity of Xianyang City was established by means of the feedback relationships between the various subsystems. The simulation results showed that if the city is being developed according to the trend-based development plan, it will be subject to severe water shortage (in a level of 9% to 35% ) in planning year since the agricultural and ecological water was diverted to the rapidly developing industry. If the city is developed in the track of resource-based and environmental protection, the ecological environment will be protected very well; however, industrial and agricultural development will be severely constrained. If the city is adopted an economic development plane, even though industry development will be rapid, the city will be subject to agricultural irrigation decreased, environment degraded, serious over-exploitation of ground water, causing 3% -5% water shortage, eventually leading to poor sustainable development. If the city is indicated to choose a coordinated development mode,a 13. 8% growth rate of industry and agriculture will be maintained,more wastewater treated will be reused, agricultural irrigation area will be expanded steadily, and ecological environment will be improved in a great deal, water shortage will be as low as 0. 4%. It suggests this plan is the optimal solution to make sure water resources carrying capacity of Xianyang City will be kept in sustainable manner.%基于系统动力学的原理和方法,将水资源承载力系统划分为工业、农业、生活、生态、水资源和污水处理回用子

  10. Mitochondrial respiratory capacity and content are normal in young insulin-resistant obese humans.

    Science.gov (United States)

    Fisher-Wellman, Kelsey H; Weber, Todd M; Cathey, Brook L; Brophy, Patricia M; Gilliam, Laura A A; Kane, Constance L; Maples, Jill M; Gavin, Timothy P; Houmard, Joseph A; Neufer, P Darrell

    2014-01-01

    Considerable debate exists about whether alterations in mitochondrial respiratory capacity and/or content play a causal role in the development of insulin resistance during obesity. The current study was undertaken to determine whether such alterations are present during the initial stages of insulin resistance in humans. Young (∼23 years) insulin-sensitive lean and insulin-resistant obese men and women were studied. Insulin resistance was confirmed through an intravenous glucose tolerance test. Measures of mitochondrial respiratory capacity and content as well as H(2)O(2) emitting potential and the cellular redox environment were performed in permeabilized myofibers and primary myotubes prepared from vastus lateralis muscle biopsy specimens. No differences in mitochondrial respiratory function or content were observed between lean and obese subjects, despite elevations in H(2)O(2) emission rates and reductions in cellular glutathione. These findings were apparent in permeabilized myofibers as well as in primary myotubes. The results suggest that reductions in mitochondrial respiratory capacity and content are not required for the initial manifestation of peripheral insulin resistance.

  11. Human Resources development and research capacity and their impact on economic growth

    Directory of Open Access Journals (Sweden)

    Zoran Ježić

    2009-12-01

    Full Text Available The goal of this research is to provide an analysis of the development of the Republic of Croatia and 110 selected countries in terms of human resource development index components and the components of the Technological Achievement Index. Developmental lags of the Republic of Croatia were determined by the bird’s eye view method in terms of the observed developmental indicators, and suggestions were provided for their development. The impact of the analysed indicators and their components on the economic growth of the Republic of Croatia and the selected countries was established by regression analysis. The paper provides possible developmental guidelines for certain components. The results of the research proved that the Human Resources Development Index is insufficient in the analysis of economic development, as well as the existence of the expected correlation between trained human resources, which enable technological progress, and economic growth of a country. Taking into consideration the correlation between the growth of the Human Resources Development Index, Research Capacity Index, Technology and Innovation Index, and the Ability to Absorb Knowledge and Technology Index and economic growth, which was determined by the application of a model, Croatia has to make additional investments in the growth of human capital and labour productivity in order to reduce developmental lags.

  12. Séverisation de l'essai de capacité de charge des lubrifiants sur machine a engrenages FZG Obtaining Greater Severity for the Load-Carrying Capacity Test for Lubricants with the Fzg Gear Machine

    Directory of Open Access Journals (Sweden)

    Ayel J.

    2006-11-01

    Full Text Available La machine à engrenages FZG reste l'appareil de laboratoire le plus utilisé pour l'évaluation de la capacité de charge des lubrifiants pour engrenages et transmissions. Mais, les différentes méthodes normalisées actuellement utilisées ne sont pas assez sévères pour bien discriminer les huiles extrême-pression actuelles en ce qui concerne leur capacité de charge. L'institut Français du Pétrole a développé une méthode beaucoup plus sévère, tout en restant aussi répétable que les méthodes classiques, sans modification de la machine ou des engrenages et, par conséquent, aisément utilisable dans tous les laboratoires. Cette nouvelle procédure est applicable à vitesse double de la vitesse normale sans accroissement de l'état des contraintes des dentures. L'utilisation de cette méthode devrait rendre de grands services aux formulateurs d'huiles et aux fabricants d'additifs pour la mise au point de leurs produits. The FZG gear machine is still the most widely used laboratory device for assessing the load-carrying capacity of lubricants for gears and transmissions. But various standardized methods currently used are not severe enough to effectively discriminate present extreme- pressure oils with regard to their load-carrying capacity. The Institut Français du Pétrole has developed a much more severe method that remains just as repeatable as conventional methods, without modifying the machine or the gears, and hence that can easily be used in all laboratories. This new procedure can be implemented at twice normal speed without any increase in the state of stresses on teeth. The use of this method should be of great service to oil formulators and additive manufacturers in the development of their products.

  13. DYNAMIC ANALYSIS OF WATER RESOURCES ECOLOGICAL FOOTPRINT AND ECOLOGICAL CARRYING CAPACITY IN YUNNAN PROVINCE%云南省水资源生态足迹与生态承载力动态分析

    Institute of Scientific and Technical Information of China (English)

    常龙芳

    2012-01-01

    利用水资源生态足迹计算模型对云南省近十年水资源生态足迹和生态承载力进行了分析,结果表明:(1)云南省近十年水资源生态承载力差异较大,2001年最高,为285×10^6hm^2,2009年最低,为175×10^6hm^2,而水资源生态足迹变化不明显;(2)人均水资源生态足迹在0.5306hm^2/人~0.5669hm^2/人,万元GDP水资源生态足迹呈逐年下降的趋势;(3)各用水指标中生产用水水资源生态足迹所占份额最大,均大于21.0×10^6hm^2,生态环境用水所占份额最小,均小于1.0×10^6hm^2。%According to the calculation model of water resources ecological footprint, the water resources ecological footprint and ecological carrying capacity in the last ten years in Yunnan Province were analyzed. The results showed: ( 1 ) There are big differences in the ecological carrying capacity in the last ten years, the maximum of 285 × 10^6hm^2 in 2001, and the minimum of 175× 10^6hm^2 in 2009, but the water resources ecological footprint is nearly on the same level; (2) The ecological footprint of water resources per capita was at the range of 0. 5306 hm^2 -0. 5669hm^2, while the water resources ecological footprint per 104 yuan GDP continued to decrease; (3) Production water resources accounted for the largest ecological footprint among all the using water index, all over 21.0 × 10^6hm^2, and ecological environment water consumption was the least, all under 1.0 × 10^6hm^2.

  14. 考虑后屈曲的复合材料加筋壁板承载能力分析%Load Carrying Capacity Analysis of Stiffened Composite Panel Considering Post-buckling

    Institute of Scientific and Technical Information of China (English)

    张国凡; 孙侠生; 孙中雷

    2015-01-01

    The load carrying capacity prediction of stiffened composite structure is an important part of air-craft designing,and the key problem is post-buckling analysis taken material failure into account.A con-cise progressive damage analysis methodology considering intralaminar failure,delamination and stiffness degradation was established based on cohesive elements and Hashin damage criteria subjected to the post-buckling analysis beared compressive loading,and UMAT subroutines of ABAQUS were developed.The comparison indicates that the load carrying capacity,failure mode and strain analysis results of this paper agree well with test results,and the relative error is less than 10% which proves the effectiveness of the present methodology.%复合材料加筋结构的承载能力预估是飞机设计中的重要内容,其关键问题就是考虑材料失效的后屈曲分析。针对复合材料加筋壁板承受压缩载荷的后屈曲承载能力预估问题,考虑层内损伤、层间分层以及刚度退化,基于内聚力单元与Hashin损伤准则,建立了一种简洁的渐进损伤分析方法,编制了相应的ABAQUS UMAT子程序,并利用复合材料加筋结构破坏试验进行了验证。验证结果表明,预估的承载能力、破坏模式和结构应力状态与物理试验结果符合得很好,承载能力误差在10%以内,证明了方法的准确性和工程实用性。

  15. An Extended Framework for Measuring the Information Capacity of the Human Motor System

    CERN Document Server

    Roos, Teemu

    2011-01-01

    Fitts' law is a fundamental tool in understanding the capacity of the human motor system. It measures information throughput in terms of the tradeoff between the speed and accuracy of motor responses. Although immensely popular, the paradigm in which Fitts' law is the principal keystone is confined to relatively simple responses in strictly prescribed stimulus-response conditions. Our goal is to generalize the framework into completely unconstrained movement. The proposed new metric is based on a subject's ability to accurately reproduce a learned movement pattern. It can accommodate recorded movement of any duration and composition, and involving contributions of any part of the body. We demonstrate the proposed method by analyzing publicly available motion capture data. Possible applications include human-computer interaction, sports science, and clinical diagnosis.

  16. Human Land-Use Practices Lead to Global Long-Term Increases in Photosynthetic Capacity

    Science.gov (United States)

    Mueller, Thomas; Tucker, Compton J.; Dressler, Gunnar; Pinzon, Jorge E.; Leimgruber, Peter; Dubayah, Ralph O.; Hurtt, George C.; Boehning-Gaese, Katrin; Fagan, William F.

    2014-01-01

    Long-term trends in photosynthetic capacity measured with the satellite-derived Normalized Difference Vegetation Index (NDVI) are usually associated with climate change. Human impacts on the global land surface are typically not accounted for. Here, we provide the first global analysis quantifying the effect of the earth's human footprint on NDVI trends. Globally, more than 20% of the variability in NDVI trends was explained by anthropogenic factors such as land use, nitrogen fertilization, and irrigation. Intensely used land classes, such as villages, showed the greatest rates of increase in NDVI, more than twice than those of forests. These findings reveal that factors beyond climate influence global long-term trends in NDVI and suggest that global climate change models and analyses of primary productivity should incorporate land use effects.

  17. Human Land-Use Practices Lead to Global Long-Term Increases in Photosynthetic Capacity

    Directory of Open Access Journals (Sweden)

    Thomas Mueller

    2014-06-01

    Full Text Available Long-term trends in photosynthetic capacity measured with the satellite-derived Normalized Difference Vegetation Index (NDVI are usually associated with climate change. Human impacts on the global land surface are typically not accounted for. Here, we provide the first global analysis quantifying the effect of the earth’s human footprint on NDVI trends. Globally, more than 20% of the variability in NDVI trends was explained by anthropogenic factors such as land use, nitrogen fertilization, and irrigation. Intensely used land classes, such as villages, showed the greatest rates of increase in NDVI, more than twice than those of forests. These findings reveal that factors beyond climate influence global long-term trends in NDVI and suggest that global climate change models and analyses of primary productivity should incorporate land use effects.

  18. The Effect of Fibronectin on the Fertilization Capacity of Human Spermatozoa

    Institute of Scientific and Technical Information of China (English)

    许复华; 崔晓; 杨抚华

    1996-01-01

    Fibronectin (Fn) is a major molecular glycoprotein that is known to play an important role in many systems involved in cell-to-cell interation and cell-to-matrix adhesion. We initially studied the effect of Fn on the fertilization capacity of human spermatozoa with a penetration test in vitro. Following co-incubation of Fn in a heterologous system (human spermatozoa and zona-free golden hamster oocytes ), we have noted a significant decrease in the rate of sperm penetration into oolemma at 2.8 μg Fn/ml,and a complete inhibition of fertilization at 15 μg Fn/ml. Besides, we noted a specific increase in the penetration rate during the co incubation of anti-Fn-serum in a heterologous system. These results suggest that extrinsic Fn binds with the Fn-receptor in the oolemma, thereby, competitively inhibiting fertilization.

  19. The state of human dimensions capacity for natural resource management: needs, knowledge, and resources

    Science.gov (United States)

    Sexton, Natalie R.; Leong, Kirsten M.; Milley, Brad J.; Clarke, Melinda M.; Teel, Tara L.; Chase, Mark A.; Dietsch, Alia M.

    2013-01-01

    The social sciences have become increasingly important in understanding natural resource management contexts and audiences, and are essential in design and delivery of effective and durable management strategies. Yet many agencies and organizations do not have the necessary resource management. We draw on the textbook definition of HD: how and why people value natural resources, what benefits people seek and derive from those resources, and how people affect and are affected by those resources and their management (Decker, Brown, and Seimer 2001). Clearly articulating how HD information can be used and integrated into natural resource management planning and decision-making is an important challenge faced by the HD field. To address this challenge, we formed a collaborative team to explore the issue of HD capacity-building for natural resource organizations and to advance the HD field. We define HD capacity as activities, efforts, and resources that enhance the ability of HD researchers and practitioners and natural managers and decision-makers to understand and address the social aspects of conservation. Specifically, we sought to examine current barriers to integration of HD into natural resource management, knowledge needed to improve HD capacity, and existing HD tools, resources, and training opportunities. We conducted a needs assessment of HD experts and practitioners, developed a framework for considering HD activities that can contribute both directly and indirectly throughout any phase of an adaptive management cycle, and held a workshop to review preliminary findings and gather additional input through breakout group discussions. This paper provides highlights from our collaborative initiative to help frame and inform future HD capacity-building efforts and natural resource organizations and also provides a list of existing human dimensions tools and resources.

  20. Angptl4 maintains in vivo repopulation capacity of CD34+ human cord blood cells.

    Science.gov (United States)

    Blank, Ulrika; Ehrnström, Birgitta; Heinz, Niels; Nilsson, Eva; Brun, Ann; Baum, Christopher; Schiedlmeier, Bernhard; Karlsson, Stefan

    2012-09-01

    Methods to expand hematopoietic stem cells (HSCs) ex vivo encompass an attractive approach that would substantially broaden the clinical applicability of HSCs derived from cord blood (CB). Recently, members of the angiopoietin-like (Angptl) family of growth factors were shown to expand both murine and human HSCs. Specifically, Angptl5 has been implicated in the expansion of human NOD/SCID-repopulating cells (SRCs) ex vivo. Here, we sought to evaluate the potential of additional Angptls to expand human SRCs from CB. Additionally, the purpose of this study was to evaluate the reproducibility of Angptl-mediated expansion of SRCs across independent experiments. Human CD34(+) cells from CB were cultured in vitro for eleven or 8 d in the presence or absence of Angptls. The reconstitution capacity of expanded cells was subsequently measured in vivo by transplantation into NOD/SCID or NSG mice and compared with that of uncultured cells. We report here that Angptl4 functions to maintain SRC activity of CD34(+) CB-derived cells ex vivo as assayed in NOD/SCID and NSG mice. However, all Angptls tested, including Angptl1, Angptl4, and Angptl5, were associated with variation between experiments. Our findings indicate that Angptl4 and Angptl5 can lead to increased engraftment capacity of SRCs, but more frequently, these factors are associated with maintenance of SRC activity during ex vivo culture. Thus, Angptl-mediated expansion of SRCs ex vivo is associated with more interexperimental variation than previously thought. We conclude that Angptls would be useful in instances where there is a need to maintain HSCs ex vivo, such as during transduction for gene therapy applications. © 2012 John Wiley & Sons A/S.

  1. Building capacity for human genetics and genomics research in Trinidad and Tobago

    Science.gov (United States)

    Roach, Allana; Warner, Wayne A.; Llanos, Adana A. M.

    2016-01-01

    Advances in human genetics and genomic sciences and the corresponding explosion of biomedical technologies have deepened current understanding of human health and revolutionized medicine. In developed nations, this has led to marked improvements in disease risk stratification and diagnosis. These advances have also led to targeted intervention strategies aimed at promoting disease prevention, prolonging disease onset, and mitigating symptoms, as in the well-known case of breast cancer and the BRCA1 gene. In contrast, in the developing nation of Trinidad and Tobago, this scientific revolution has not translated into the development and application of effective genomics-based interventions for improving public health. While the reasons for this are multifactorial, the underlying basis may be rooted in the lack of pertinence of internationally driven genomics research to the local public health needs in the country, as well as a lack of relevance of internationally conducted genetics research to the genetic and environmental contexts of the population. Indeed, if Trinidad and Tobago is able to harness substantial public health benefit from genetics/genomics research, then there is a dire need, in the near future, to build local capacity for the conduct and translation of such research. Specifically, it is essential to establish a national human genetics/genomics research agenda in order to build sustainable human capacity through education and knowledge transfer and to generate public policies that will provide the basis for the creation of a mutually beneficial framework (including partnerships with more developed nations) that is informed by public health needs and contextual realities of the nation. PMID:26837529

  2. Overexpression of PGC-1α Increases Fatty Acid Oxidative Capacity of Human Skeletal Muscle Cells

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    Nataša Nikolić

    2012-01-01

    Full Text Available We investigated the effects of PGC-1α (peroxisome proliferator-activated receptor γ coactivator-1α overexpression on the oxidative capacity of human skeletal muscle cells ex vivo. PGC-1α overexpression increased the oxidation rate of palmitic acid and mRNA expression of genes regulating lipid metabolism, mitochondrial biogenesis, and function in human myotubes. Basal and insulin-stimulated deoxyglucose uptake were decreased, possibly due to upregulation of PDK4 mRNA. Expression of fast fiber-type gene marker (MHCIIa was decreased. Compared to skeletal muscle in vivo, PGC-1α overexpression increased expression of several genes, which were downregulated during the process of cell isolation and culturing. In conclusion, PGC-1α overexpression increased oxidative capacity of cultured myotubes by improving lipid metabolism, increasing expression of genes involved in regulation of mitochondrial function and biogenesis, and decreasing expression of MHCIIa. These results suggest that therapies aimed at increasing PGC-1α expression may have utility in treatment of obesity and obesity-related diseases.

  3. Safe housing ensured by an electric field screen that excludes insect-net permeating haematophagous mosquitoes carrying human pathogens

    Science.gov (United States)

    Matsuda, Y.; Kakutani, K.; Nonomura, T.; Kimbara, J.; Osamura, K.; Kusakar, S.; Toyoda, H.

    2015-10-01

    An electric field screen can be used to keep mosquitoes out of houses with open windows. In this study, doubly charged dipolar electric field screens (DD-screens) were used to capture mosquitoes entering through a window. The screen had two components: three layers of insulated conductor iron wires (ICWs) in parallel arrays and two electrostatic direct current (DC) voltage generators that supplied negative or positive voltages to the ICWs. Within each layer, the ICWs were parallel at 5-mm intervals, and connected to each other and to a negative or positive voltage generator. The negatively and positively charged ICWs are represented as ICW(-) and ICW(+), respectively. The screen consisted of one ICW(+) layer with an ICW(-) layer on either side. The Asian tiger mosquito (Aedes albopictus) and house mosquito (Culex pipiens) were used as models of vectors carrying viral pathogens. Adult mosquitoes were blown into the space between the ICWs by sending compressed air through the tip of an insect aspirator to determine the voltage range that captured all of the test insects. Wind speed was measured at the surface of the ICW using a sensitive anemometer. The result showed that at ≥ 1.2 kV, the force was strong enough that the ICWs captured all of the mosquitoes, despite a wind speed of 7 m/s. Therefore, the DD-screen could serve as a physical barrier to prevent noxious mosquitoes from entering houses with good air penetration.

  4. Epigenetic Characterization of the FMR1 Promoter in Induced Pluripotent Stem Cells from Human Fibroblasts Carrying an Unmethylated Full Mutation

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    de Esch, Celine E.F.; Ghazvini, Mehrnaz; Loos, Friedemann; Schelling-Kazaryan, Nune; Widagdo, W.; Munshi, Shashini T.; van der Wal, Erik; Douben, Hannie; Gunhanlar, Nilhan; Kushner, Steven A.; Pijnappel, W.W.M. Pim; de Vrij, Femke M.S.; Geijsen, Niels; Gribnau, Joost; Willemsen, Rob

    2014-01-01

    Summary Silencing of the FMR1 gene leads to fragile X syndrome, the most common cause of inherited intellectual disability. To study the epigenetic modifications of the FMR1 gene during silencing in time, we used fibroblasts and induced pluripotent stem cells (iPSCs) of an unmethylated full mutation (uFM) individual with normal intelligence. The uFM fibroblast line carried an unmethylated FMR1 promoter region and expressed normal to slightly increased FMR1 mRNA levels. The FMR1 expression in the uFM line corresponds with the increased H3 acetylation and H3K4 methylation in combination with a reduced H3K9 methylation. After reprogramming, the FMR1 promoter region was methylated in all uFM iPSC clones. Two clones were analyzed further and showed a lack of FMR1 expression, whereas the presence of specific histone modifications also indicated a repressed FMR1 promoter. In conclusion, these findings demonstrate that the standard reprogramming procedure leads to epigenetic silencing of the fully mutated FMR1 gene. PMID:25358783

  5. Epigenetic Characterization of the FMR1 Promoter in Induced Pluripotent Stem Cells from Human Fibroblasts Carrying an Unmethylated Full Mutation

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    Celine E.F. de Esch

    2014-10-01

    Full Text Available Silencing of the FMR1 gene leads to fragile X syndrome, the most common cause of inherited intellectual disability. To study the epigenetic modifications of the FMR1 gene during silencing in time, we used fibroblasts and induced pluripotent stem cells (iPSCs of an unmethylated full mutation (uFM individual with normal intelligence. The uFM fibroblast line carried an unmethylated FMR1 promoter region and expressed normal to slightly increased FMR1 mRNA levels. The FMR1 expression in the uFM line corresponds with the increased H3 acetylation and H3K4 methylation in combination with a reduced H3K9 methylation. After reprogramming, the FMR1 promoter region was methylated in all uFM iPSC clones. Two clones were analyzed further and showed a lack of FMR1 expression, whereas the presence of specific histone modifications also indicated a repressed FMR1 promoter. In conclusion, these findings demonstrate that the standard reprogramming procedure leads to epigenetic silencing of the fully mutated FMR1 gene.

  6. Immunogenic comparison of chimeric adenovirus 5/35 vector carrying optimized human immunodeficiency virus clade C genes and various promoters.

    Science.gov (United States)

    Shoji, Masaki; Yoshizaki, Shinji; Mizuguchi, Hiroyuki; Okuda, Kenji; Shimada, Masaru

    2012-01-01

    Adenovirus vector-based vaccine is a promising approach to protect HIV infection. However, a recent phase IIb clinical trial using the vector did not show its protective efficacy against HIV infection. To improve the vaccine, we explored the transgene protein expression and its immunogenicity using optimized codon usage, promoters and adaptors. We compared protein expression and immunogenicity of adenovirus vector vaccines carrying native or codon usage-optimized HIV-1 clade C gag and env genes expression cassettes driven by different promoters (CMV, CMVi, and CA promoters) and adapters (IRES and F2A). The adenovirus vector vaccine containing optimized gag gene produced higher Gag protein expression and induced higher immune responses than the vector containing native gag gene in mice. Furthermore, CA promoter generated higher transgene expression and elicited higher immune responses than other two popularly used promoters (CMV and CMVi). The second gene expression using F2A adaptor resulted in higher protein expression and immunity than that of using IRES and direct fusion protein. Taken together, the adenovirus vector containing the expression cassette with CA promoter, optimized HIV-1 clade C gene and an F2A adaptor produced the best protein expression and elicited the highest transgene-specific immune responses. This finding would be promising for vaccine design and gene therapy.

  7. 北京密云水源地村级尺度生态安全承载力分析%Analysis of Eco-security Carrying Capacity on Village Scale in Miyun Reservoir, Beijing

    Institute of Scientific and Technical Information of China (English)

    胡艳霞; 周连第; 李红; 王亚芝; 解海静

    2011-01-01

    It' s important to study on the eco-security capacity of a social-economic-natural compounding system in certain areas, especially for sustainable development in urban watershed. The author took a village of Miyun watershed for an example to study the eco-security carrying capacity by using the method of system dynamics (SD) model simulation, aimed to solve the problems between industry development and environment. It explained that small agro-bio-cycle system could increase eco-security carrying capacity remarkably, but must be combined with village tour which developed rapidly. During the research, the eco-security had been divided into 4 subsystem, such as population, bio-cycle agriculture, village tourism and waste resources, then 9 schemes had been searched and system dynamics model had been built. The simulation results showed that: (1) mushroom industry was the ligament for the small eco-cycle system, and if all the greenhouse in the village had been used to produce mushroom, the eco-security would be better in the coming 10 years; (2) if the stalks, cattle manure, tree branches, mushroom sticks and waste water had been treated to 60%, the balance point for ecology and economy was coming, that is, the ecology and economy of the village would be in order and sustainable in the coming 10 years.%区域生态安全承载力的研究对于一定区域的社会-经济-自然复合生态经济系统的持续发展,尤其是大都市水源地的持续发展具有重要意义.笔者以北京密云水源地的1个村庄为案例,针对产业发展与环境矛盾突出问题,采用系统动力学的方法,从村级尺度上阐述了产业发展的农业生物小循环方式是显著提高生态安全承栽力的有效方法,但同时还需紧密结合该区域内发展迅速的民俗旅游产业,才能有效解决北京水源地的持续发展问题.研究中将生态安全承载力系统划分为人口、生物循环农业、旅游、废污资源4个子系统,构建

  8. Migration capacity of human umbilical cord mesenchymal stem cells towards glioma in vivo*

    Institute of Scientific and Technical Information of China (English)

    Cungang Fan; Dongliang Wang; Qingjun Zhang; Jingru Zhou

    2013-01-01

    High-grade glioma is the most common malignant primary brain tumor in adults. The poor prognosis of glioma, combined with a resistance to currently available treatments, necessitates the ment of more effective tumor-selective therapies. Stem cel-based therapies are emerging as novel cel-based delivery vehicle for therapeutic agents. In the present study, we successful y isolated human umbilical cord mesenchymal stem cel s by explant culture. The human umbilical cord senchymal stem cel s were adherent to plastic surfaces, expressed specific surface phenotypes of mesenchymal stem cel s as demonstrated by flow cytometry, and possessed multi-differentiation potentials in permissive induction media in vitro. Furthermore, human umbilical cord mesenchymal stem cel s demonstrated excel ent glioma-specific targeting capacity in established rat glioma models after intratumoral injection or contralateral ventricular administration in vivo. The excellent glioma-specific targeting ability and extensive intratumoral distribution of human umbilical cord mesenchymal stem cel s indicate that they may serve as a novel cel ular vehicle for delivering the-rapeutic molecules in glioma therapy.

  9. 基于土地消纳粪便能力的畜禽养殖承载力%Carrying capacity of livestock and poultry breeding based on feces disposal volume of land

    Institute of Scientific and Technical Information of China (English)

    潘瑜春; 孙超; 刘玉; 唐秀美; 任艳敏

    2015-01-01

    The livestock and poultry breeding industry in Pinggu district of Beijing developed rapidly. Compared with 1992, the slaughter of pigs and chickens increased by 18.95% and 22.29%, and the breeding stock of cattle, sheep, laying hens increased by 35.51%, 40.28% and 10.29%, especially the pig slaughter and egg production, which occupied by 11.81% and 20.21% of Beijing respectively. Gradually, the environmental pressure appears caused by the rapid growth of livestock and poultry manure quantity. And Pinggu district, the ecological conservation district, ecological barrier and water source protection of Beijing, is of a great importance to keep the environment of Beijing sustainable and healthy. As a result, it is important to connect farming and aquaculture, construct the circulation of agriculture economy chain, and determine the scale of farming according to local conditions. Based on the characteristic that orchard land took a large part of agricultural land, this paper set the cultivated land and orchard nitrogen limited standard, through calculation of the environmental capacity of farmland nitrogen, the poultry and animal feces pollution risk index and potential of livestock and poultry, then assessed the livestock carrying potential and potential contamination and analyzed the farmland and orchards’ livestock carrying potential of Pinggu and its town. The results indicated that: 1) During 2012, the total manure of Pinggu was 591 100 tons, containing nitrogen and phosphorus respectively 4 721, 998 t, which meant a huge organic resource, made it available to reduce the fertilizer use, and can effectively improve soil quality and the quality of the crops; 2) For ecological conservation development area, as the orchards occupied a large proportion of agricultural land, the agricultural land of livestock and poultry manure loading status achieved by taking the cultivated land and orchard as disposal site, may be more practical. The average manure load of

  10. 基于人粮关系的咸宁市土地承载力研究%Study on Carrying Capacity of Land Resources in Xianning City Based on Population-Grain Relationship

    Institute of Scientific and Technical Information of China (English)

    郝汉舟; 汪华

    2014-01-01

    In this study, the grey model GM(1,1) and the Logistic model were used to predict the changes in the future popu-lation, farmland and grain yield per unit area of Xianning city , Hubei province .The piecewise-revised model by using environ-mental factors was adopted to calculate the production potential of arable land in Xianning city .The results showed that:(1) the av-erage grain yield per unit area of arable land in Xianning city in 2011 was 6575.4 kg/hm2 , the theoretical production potential of ar-able land was 23760.2 kg/hm2, and the former accounted for 27.7% of the latter; (2) in 2011, the carrying capacity of arable land for food in Xianning city was great , and the population carrying index LCCI of every county ( except for Jiayu county ) was grea-ter than 1;(3) it was predicted that the grain yield per unit area of Xianning city in 2015 and 2025 was 8473.1 kg/hm2 and 9441. 7 kg/hm2 respectively;the predicted population of this city in 2015 and 2025 was 3.019 million and 3.243 million respectively;(4) as for the well-off-type population carrying capacity , LCCI in Xianning city was 0.79 in 2015 and 0.59 in 2025, and the population saturability revealed a downward trend .%以湖北省咸宁市为例,采用灰色模型GM(1,1)及逻辑斯蒂模型分别预测咸宁市未来人口、耕地及粮食单产的变化。采用环境因子逐段订正模型计算咸宁市土地耕地生产潜力,研究结果表明:咸宁市2011年耕地单产平均水平为6575.4 kg/hm2,理论计算的耕地生产潜力为23760.2 kg/hm2,实际单产为潜在耕地生产潜力的27.7%。2011年咸宁市耕地粮食承载力压力很大,除嘉鱼县外,人口承载指数LCCI均大于1。2015年和2025年咸宁市粮食单产预测为8473.1 kg/hm2和9441.7 kg/hm2。2015年和2025年人口预测为301.9万和324.3万。对于小康型人口承载力来讲,人口承载指数LCCI,在2015年为0.79,在2025年为0.59,人口饱和度呈现下降的趋势。

  11. A comprehensive mapping of the current capacity for human nutrition training in Cameroon

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    Roger Sodjinou

    2016-01-01

    Full Text Available Background: There is consensus among stakeholders in Cameroon on the need to develop and strengthen human resource capacity for nutrition. This study was conducted to provide a comprehensive mapping of the current capacity for tertiary-level human nutrition training in Cameroon. Design: Participating institutions included university-level institutions offering dedicated nutrition degree programs or other programs in which nutrition courses were taught. A semi-structured questionnaire administered during in-person interviews was used to collect data on existing programs and content of training curricula. Nutrition curricula were reviewed against the following criteria: intended objectives, coverage of nutrition topics, and teaching methods. Results: In total, five nutrition degree programs (four undergraduate programs and one master's program were identified. Three additional programs were about to be launched at the time of data collection. We did not find any doctorate degree programs in nutrition. All the undergraduate programs only had little focus on public health nutrition whereas the master's program in our sample offered a good coverage of all dimensions of human nutrition including basic and applied nutrition. The predominant teaching method was didactic lecture in all the programs. We did not find any formal documentation outlining the competencies that students were expected to gain upon completion of these programs. Nutrition courses in agricultural and health schools were limited in terms of contact hours and scope. Public health nutrition was not covered in any of the health professional schools surveyed. We found no institution offering in-service nutrition training at the time of the study. Conclusions: Based on our findings, we recommend that nutrition training programs in Cameroon be redesigned to make them more responsive to the public health needs of the country.

  12. Imaging characteristics, tissue distribution, and spread of a novel oncolytic vaccinia virus carrying the human sodium iodide symporter.

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    Dana Haddad

    Full Text Available INTRODUCTION: Oncolytic viruses show promise for treating cancer. However, to assess therapy and potential toxicity, a noninvasive imaging modality is needed. This study aims to determine the in vivo biodistribution, and imaging and timing characteristics of a vaccinia virus, GLV-1h153, encoding the human sodium iodide symporter (hNIS. METHODS: GLV-1h153 was modified from GLV-1h68 to encode the hNIS gene. Timing of cellular uptake of radioiodide (131I in human pancreatic carcinoma cells PANC-1 was assessed using radiouptake assays. Viral biodistribution was determined in nude mice bearing PANC-1 xenografts, and infection in tumors confirmed histologically and optically via Green Fluorescent Protein (GFP and bioluminescence. Timing characteristics of enhanced radiouptake in xenografts were assessed via (124I-positron emission tomography (PET. Detection of systemic administration of virus was investigated with both (124I-PET and 99m-technecium gamma-scintigraphy. RESULTS: GLV-1h153 successfully facilitated time-dependent intracellular uptake of (131I in PANC-1 cells with a maximum uptake at 24 hours postinfection (P<0.05. In vivo, biodistribution profiles revealed persistence of virus in tumors 5 weeks postinjection at 10(9 plaque-forming unit (PFU/gm tissue, with the virus mainly cleared from all other major organs. Tumor infection by GLV-1h153 was confirmed via optical imaging and histology. GLV-1h153 facilitated imaging virus replication in tumors via PET even at 8 hours post radiotracer injection, with a mean %ID/gm of 3.82 ± 0.46 (P<0.05 2 days after intratumoral administration of virus, confirmed via tissue radiouptake assays. One week post systemic administration, GLV-1h153-infected tumors were detected via (124I-PET and 99m-technecium-scintigraphy. CONCLUSION: GLV-1h153 is a promising oncolytic agent against pancreatic cancer with a promising biosafety profile. GLV-1h153 facilitated time-dependent hNIS-specific radiouptake in pancreatic

  13. Synthesis of multivalent sialyllactosamine-carrying glyco-nanoparticles with high affinity to the human influenza virus hemagglutinin.

    Science.gov (United States)

    Ogata, Makoto; Umemura, Seiichiro; Sugiyama, Naohiro; Kuwano, Natsuki; Koizumi, Ami; Sawada, Tadakazu; Yanase, Michiyo; Takaha, Takeshi; Kadokawa, Jun-Ichi; Usui, Taichi

    2016-11-20

    A series of multivalent sialoglyco-conjugated nanoparticles were efficiently synthesized by using highly-branched α-glucuronic acid-linked cyclic dextrins (GlcA-HBCD) as a backbone. The sialoglycoside-moieties, with varying degrees of substitution, could be incorporated onto the preformed nanoparticles. These synthesized particles, which are highly soluble in aqueous solution, were shown to have a spherical nanostructure with a diameter of approximately 15nm. The interactions of the sialoglyco-nanoparticles (Neu5Acα2,6LacNAc-GlcA-HBCDs) with human influenza virus strain A/Beijing/262/95 (H1N1) were investigated using a hemagglutination inhibition assay. The sialoglyco-nanoparticle, in which the number of sialic acid substitution is 30, acted as a powerful inhibitor of virus binding activity. We show that both distance and multiplicity of effective ligand-virus formation play important roles in enhancing viral inhibition. Our results indicate that the GlcA-HBCD backbone can be used as a novel spherical nanocluster material for preparing a variety of glyco-nanoparticles to facilitate molecular recognition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Differentiation of Human Mesenchymal Stem Cells into Insulin Producing Cells by Using A Lentiviral Vector Carrying PDX1

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    Amir Allahverdi

    2015-07-01

    Full Text Available Objective: Type I diabetes is an immunologically-mediated devastation of insulin producing cells (IPCs in the pancreatic islet. Stem cells that produce β-cells are a new promising tool. Adult stem cells such as mesenchymal stem cells (MSCs are self renewing multi potent cells showing capabilities to differentiate into ectodermal, mesodermal and endodermal tissues. Pancreatic and duodenal homeobox factor 1 (PDX1 is a master regulator gene required for embryonic development of the pancreas and is crucial for normal pancreatic islets activities in adults. Materials and Methods: We induced the over-expression of the PDX1 gene in human bone marrow MSCs (BM-MSCs by Lenti-PDX1 in order to generate IPCs. Next, we examine the ability of the cells by measuring insulin/c-peptide production and INSULIN and PDX1 gene expressions. Results: After transduction, MSCs changed their morphology at day 5 and gradually differentiated into IPCs. INSULIN and PDX1 expressions were confirmed by real time polymerase chain reaction (RT-PCR and immunostaining. IPC secreted insulin and C-peptide in the media that contained different glucose concentrations. Conclusion: MSCs differentiated into IPCs by genetic manipulation. Our result showed that lentiviral vectors could deliver PDX1 gene to MSCs and induce pancreatic differentiation.

  15. The carrying pigeons of the cell: exosomes and their role in infectious diseases caused by human pathogens.

    Science.gov (United States)

    Fleming, Adam; Sampey, Gavin; Chung, Myung-Chul; Bailey, Charles; van Hoek, Monique L; Kashanchi, Fatah; Hakami, Ramin M

    2014-07-01

    Exosomes have recently been classified as the newest family members of 'bioactive vesicles' that function to promote intercellular communication. Long ignored and thought to be only a mechanism by which cellular waste is removed, exosomes have garnered a huge amount of interest in recent years as their critical functions in maintaining homeostasis through intercellular communication and also in different types of diseases have been demonstrated. Many groundbreaking studies of exosome functions have been performed in the cancer field and the infectious disease areas of study, revealing the importance and also the fascinating complexity of exosomal packaging, targeting, and functions. Selective packaging of exosomes in response to the type of infection, exosomal modulation of the immune response and host signaling pathways, exosomal regulation of pathogen spread, and effects of exosomes on the degree of pathogenesis have all been well documented. In this review, we provide a synthesis of the current understanding of the role of exosomes during infections caused by human pathogens and discuss the implications of these findings for a better understanding of pathogenic mechanisms and future therapeutic and diagnostic applications.

  16. The mesenchymal stem cells derived from transgenic mice carrying human coagulation factor VIII can correct phenotype in hemophilia A mice.

    Science.gov (United States)

    Wang, Qing; Gong, Xiuli; Gong, Zhijuan; Ren, Xiaoyie; Ren, Zhaorui; Huang, Shuzhen; Zeng, Yitao

    2013-12-20

    Hemophilia A (HA) is an inherited X-linked recessive bleeding disorder caused by coagulant factor VIII (FVIII) deficiency. Previous studies showed that introduction of mesenchymal stem cells (MSCs) modified by FVIII-expressing retrovirus may result in phenotypic correction of HA animals. This study aimed at the investigation of an alternative gene therapy strategy that may lead to sustained FVIII transgene expression in HA mice. B-domain-deleted human FVIII (hFVIIIBD) vector was microinjected into single-cell embryos of wild-type mice to generate a transgenic mouse line, from which hFVIIIBD-MSCs were isolated, followed by transplantation into HA mice. RT-PCR and real-time PCR analysis demonstrated the expression of hFVIIIBD in multi-organs of recipient HA mice. Immunohistochemistry showed the presence of hFVIIIBD positive staining in multi-organs of recipient HA mice. ELISA indicated that plasma hFVIIIBD level in recipient mice reached its peak (77 ng/mL) at the 3rd week after implantation, and achieved sustained expression during the 5-week observation period. Plasma FVIII activities of recipient HA mice increased from 0% to 32% after hFVIIIBD-MSCs transplantation. APTT (activated partial thromboplastin time) value decreased in hFVIIIBD-MSCs transplanted HA mice compared with untreated HA mice (45.5 s vs. 91.3 s). Our study demonstrated an effective phenotypic correction in HA mice using genetically modified MSCs from hFVIIIBD transgenic mice. Copyright © 2013. Published by Elsevier Ltd.

  17. Generation and Characterization of a Transgenic Mouse Carrying a Functional Human β-Globin Gene with the IVSI-6 Thalassemia Mutation

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    Giulia Breveglieri

    2015-01-01

    Full Text Available Mouse models that carry mutations causing thalassemia represent a suitable tool to test in vivo new mutation-specific therapeutic approaches. Transgenic mice carrying the β-globin IVSI-6 mutation (the most frequent in Middle-Eastern regions and recurrent in Italy and Greece are, at present, not available. We report the production and characterization of a transgenic mouse line (TG-β-IVSI-6 carrying the IVSI-6 thalassemia point mutation within the human β-globin gene. In the TG-β-IVSI-6 mouse (a the transgenic integration region is located in mouse chromosome 7; (b the expression of the transgene is tissue specific; (c as expected, normally spliced human β-globin mRNA is produced, giving rise to β-globin production and formation of a human-mouse tetrameric chimeric hemoglobin αmu-globin2/βhu-globin2 and, more importantly, (d the aberrant β-globin-IVSI-6 RNAs are present in blood cells. The TG-β-IVSI-6 mouse reproduces the molecular features of IVSI-6 β-thalassemia and might be used as an in vivo model to characterize the effects of antisense oligodeoxynucleotides targeting the cryptic sites responsible for the generation of aberrantly spliced β-globin RNA sequences, caused by the IVSI-6 mutation. These experiments are expected to be crucial for the development of a personalized therapy for β-thalassemia.

  18. Generation and Characterization of a Transgenic Mouse Carrying a Functional Human β-Globin Gene with the IVSI-6 Thalassemia Mutation

    Science.gov (United States)

    Mancini, Irene; Lampronti, Ilaria; Salvatori, Francesca; Fabbri, Enrica; Zuccato, Cristina; Cosenza, Lucia C.; Montagner, Giulia; Borgatti, Monica; Altruda, Fiorella; Fagoonee, Sharmila; Carandina, Gianni; Aiello, Vincenzo; Breda, Laura; Rivella, Stefano; Gambari, Roberto

    2015-01-01

    Mouse models that carry mutations causing thalassemia represent a suitable tool to test in vivo new mutation-specific therapeutic approaches. Transgenic mice carrying the β-globin IVSI-6 mutation (the most frequent in Middle-Eastern regions and recurrent in Italy and Greece) are, at present, not available. We report the production and characterization of a transgenic mouse line (TG-β-IVSI-6) carrying the IVSI-6 thalassemia point mutation within the human β-globin gene. In the TG-β-IVSI-6 mouse (a) the transgenic integration region is located in mouse chromosome 7; (b) the expression of the transgene is tissue specific; (c) as expected, normally spliced human β-globin mRNA is produced, giving rise to β-globin production and formation of a human-mouse tetrameric chimeric hemoglobin mu α-globin2/hu β-globin2 and, more importantly, (d) the aberrant β-globin-IVSI-6 RNAs are present in blood cells. The TG-β-IVSI-6 mouse reproduces the molecular features of IVSI-6 β-thalassemia and might be used as an in vivo model to characterize the effects of antisense oligodeoxynucleotides targeting the cryptic sites responsible for the generation of aberrantly spliced β-globin RNA sequences, caused by the IVSI-6 mutation. These experiments are expected to be crucial for the development of a personalized therapy for β-thalassemia. PMID:26097845

  19. Description of urolithin production capacity from ellagic acid of two human intestinal Gordonibacter species.

    Science.gov (United States)

    Selma, María V; Beltrán, David; García-Villalba, Rocío; Espín, Juan C; Tomás-Barberán, Francisco A

    2014-08-01

    Ellagitannin and ellagic acid metabolism to urolithins in the gut shows a large human interindividual variability and this has been associated with differences in the colon microbiota. In the present study we describe the isolation of one urolithin-producing strain from the human faeces of a healthy volunteer and the ellagic acid transformation to different urolithin metabolites by two species of intestinal bacteria. The isolate belongs to a new species described as Gordonibacter urolithinfaciens, sp. nov. The type strain of the Gordonibacter genus, Gordonibacter pamelaeae DSM 19378(T), was also demonstrated to produce urolithins. Both human intestinal bacteria grew similarly in the presence and absence of ellagic acid at 30 μM concentration. Ellagic acid catabolism and urolithin formation occurred during the stationary phase of the growth of the bacteria under anaerobic conditions. The HPLC-MS analyses showed the sequential production of pentahydroxy-urolithin (urolithin M-5), tetrahydroxy-urolithin (urolithin M-6) and trihydroxy-urolithin (urolithin C), while dihydroxy-urolithins (urolithin A and isourolithin A), and monohydroxy-urolithin (urolithin B) were not produced in pure cultures. Consequently, either other bacteria from the gut or the physiological conditions found in vivo are necessary for completing metabolism until the final urolithins (dihydroxy and monohydroxy urolithins) are produced. This is the first time that the urolithin production capacity of pure strains has been demonstrated. The identification of the urolithin-producing bacteria is a relevant outcome as urolithin implication in health (cardiovascular protection, anti-inflammatory and anticarcinogenic properties) has been supported by different bioassays and urolithins can be used in the development of functional foods and nutraceuticals. This study represents an initial work that opens interesting possibilities of describing enzymatic activities involved in urolithin production that can

  20. POPULATION DENSITIES AND THE RANGE-CARRYING ...

    African Journals Online (AJOL)

    CAPACITY FOR LARGE MAMMALS IN QUEEN ELIZABETH ... The highest known densities oflarge terrestrial mammals occur on the grasslands in ...... It is estimated that the proper average biomass carrying capacity for the several herbivore.

  1. Genome mining unveils widespread natural product biosynthetic capacity in human oral microbe Streptococcus mutans

    Science.gov (United States)

    Liu, Liwei; Hao, Tingting; Xie, Zhoujie; Horsman, Geoff P.; Chen, Yihua

    2016-01-01

    Streptococcus mutans is a major pathogen causing human dental caries. As a Gram-positive bacterium with a small genome (about 2 Mb) it is considered a poor source of natural products. Due to a recent explosion in genomic data available for S. mutans strains, we were motivated to explore the natural product production potential of this organism. Bioinformatic characterization of 169 publically available genomes of S. mutans from human dental caries revealed a surprisingly rich source of natural product biosynthetic gene clusters. Anti-SMASH analysis identified one nonribosomal peptide synthetase (NRPS) gene cluster, seven polyketide synthase (PKS) gene clusters and 136 hybrid PKS/NRPS gene clusters. In addition, 211 ribosomally synthesized and post-translationally modified peptides (RiPPs) clusters and 615 bacteriocin precursors were identified by a combined analysis using BAGEL and anti-SMASH. S. mutans harbors a rich and diverse natural product genetic capacity, which underscores the importance of probing the human microbiome and revisiting species that have traditionally been overlooked as “poor” sources of natural products. PMID:27869143

  2. Capacity of Human Dental Follicle Cells to Differentiate into Neural Cells In Vitro

    Directory of Open Access Journals (Sweden)

    Shingo Kanao

    2017-01-01

    Full Text Available The dental follicle is an ectomesenchymal tissue surrounding the developing tooth germ. Human dental follicle cells (hDFCs have the capacity to commit to differentiation into multiple cell types. Here we investigated the capacity of hDFCs to differentiate into neural cells and the efficiency of a two-step strategy involving floating neurosphere-like bodies for neural differentiation. Undifferentiated hDFCs showed a spindle-like morphology and were positive for neural markers such as nestin, β-III-tubulin, and S100β. The cellular morphology of several cells was neuronal-like including branched dendrite-like processes and neurites. Next, hDFCs were used for neurosphere formation in serum-free medium containing basic fibroblast growth factor, epidermal growth factor, and B27 supplement. The number of cells with neuronal-like morphology and that were strongly positive for neural markers increased with sphere formation. Gene expression of neural markers also increased in hDFCs with sphere formation. Next, gene expression of neural markers was examined in hDFCs during neuronal differentiation after sphere formation. Expression of Musashi-1 and Musashi-2, MAP2, GFAP, MBP, and SOX10 was upregulated in hDFCs undergoing neuronal differentiation via neurospheres, whereas expression of nestin and β-III-tubulin was downregulated. In conclusion, hDFCs may be another optimal source of neural/glial cells for cell-based therapies to treat neurological diseases.

  3. Exploitation Potential and Carrying Capacity of Water Resources of the Yinghe River Basin%颍河流域水资源开发潜力与承载力分析

    Institute of Scientific and Technical Information of China (English)

    陈杰; 欧阳志云

    2011-01-01

    Water pollution and water shortage is a key factor to affect the eco - socio - economic sustainable development in the Ying River Basin By using water load index and building water supple and demand equilibrium model, this paper analyzed the exploitation potential and population carrying capacity of the basin' s water resources. The results showed that water load index of the overall basin was 19. 24, about half of counties and cities greater than 20, which suggested a high degree of water resources utilization and small potential of further development for the basin. According to statistical data, the average amount of water resources of Yinghe River Basin is 94. 51 × 108m3. In addition, there are about 23.69 × 1O8m3 of water that can be quoted from outside the basin in the future. Based on the total amount of available water, the water resources carrying capacity ( WRCC ) of Yinghe River Basin was 27. 33 million persons in 2008, overloading 10. 88%. The equilibrium model predicts that the basin' s WRCC is 35.91 million persons in 2020, 11.62% higher than the expected population. Because of serious surface water pollution, the actual WRCC may be smaller than the above values, if the effects of water quality, water supply guarantee rate and climate changing were considered. These results provide important references for Yinghe River Basin to use water resources rationally, promote saving water and pollution control and plan long - term socio - economic development.%水环境污染和水资源短缺是影响颍河流域生态社会经济可持续发展的重要因素.研究通过水资源负载指数、水资源供需平衡模型分析了颍河流域水资源的开发利用潜力和人口承载力.结果表明,颍河流域水资源利用程度较高,流域整体负载指数为19.24,约一半县市的负载指数大于20,今后进一步开发的潜力较小;流域多年平均水资源量为94.51亿m3,可引用流域外水资源潜力约23.69亿M3,以水资源

  4. 基于开发区规划环评的土地资源承载力评价%Evaluation of land resources carrying capacity of development zone based on planning environment impact assessment

    Institute of Scientific and Technical Information of China (English)

    傅世锋; 张平; 蒋金龙

    2012-01-01

    Assessment of land resources carrying capacity is the key point of planning environment impact assessment and the main foundation to determine whether the planning could be implemented or not. With the help of the space analysis function of Geographic Information System, and selecting altitude, slope, land use type, distance from resident land, distance from main traffic roads, and distance from environmentally sensitive area as the sensitive factors, a comprehensive assessment on the ecological sensitivity and its spatial distribution in Zhangzhou Merchants Economic and Technological Development Zone, Fujian Province of East China was conducted, and the assessment results were combined with the planning land layout diagram for the ecological suitability analysis. In the Development Zone, 84.0% of resident land, 93. 1% of industrial land, 86.0% of traffic land, and 76. 0% of other constructive lands in planning were located in insensitive and gently sensitive areas, and thus, the implement of the land use planning generally had little impact on the ecological environment, and the land resources in the planning area was able to meet the land use demand. The assessment of the population carrying capacity with ecological land as the limiting factor indicated that in considering the highly sensitive area and 60% of the moderately sensitive area as ecological land, the population within the Zone in the planning could reach 240000, and the available land area per capita could be 134. 0 m2. Such a planned population scale is appropriate, according to the related standards of constructive land.%土地资源承载力评价是规划环境影响评价的重点,是决定规划是否可以实施的重要依据.基于地理信息系统技术的空间分析功能,选取高程、坡度、土地利用现状、距居民点距离、距主要交通道路距离和距环境敏感区距离作为敏感因子,综合评价了漳州招商局经济技术开发区生态敏感性程度及其

  5. Recombinant human growth hormone improves cognitive capacity in a pain patient exposed to chronic opioids.

    Science.gov (United States)

    Rhodin, A; von Ehren, M; Skottheim, B; Grönbladh, A; Ortiz-Nieto, F; Raininko, R; Gordh, T; Nyberg, F

    2014-07-01

    During recent decades, the increasing use of opioids for chronic non-cancer pain has raised concerns regarding tolerance, addiction, and importantly cognitive dysfunction. Current research suggests that the somatotrophic axis could play an important role in cognitive function. Administration of growth hormone (GH) to GH-deficient humans and experimental animals has been shown to result in significant improvements in cognitive capacity. In this report, a patient with cognitive disabilities resulting from chronic treatment with opioids for neuropathic pain received recombinant human growth hormone (rhGH) replacement therapy. A 61-year-old man presented with severe cognitive dysfunction after long-term methadone treatment for intercostal neuralgia and was diagnosed with GH insufficiency by GH releasing hormone-arginine testing. The effect of rhGH replacement therapy on his cognitive capacity and quality of life was investigated. The hippocampal volume was measured using magnetic resonance imaging, and the ratios of the major metabolites were calculated using proton magnetic resonance spectroscopy. Cognitive testing revealed significant improvements in visuospatial cognitive function after rhGH. The hippocampal volume remained unchanged. In the right hippocampus, the N-acetylaspartate/creatine ratio (reflecting nerve cell function) was initially low but increased significantly during rhGH treatment, as did subjective cognitive, physical and emotional functioning. This case report indicates that rhGH replacement therapy could improve cognitive behaviour and well-being, as well as hippocampal metabolism and functioning in opioid-treated patients with chronic pain. The idea that GH could affect brain function and repair disabilities induced by long-term exposure to opioid analgesia is supported.

  6. 水电梯级开发对生态承载力影响的研究%Evaluation of the ecosystem carrying capacity impact caused by the cascade hydropower development

    Institute of Scientific and Technical Information of China (English)

    王丽萍; 郑江涛; 周晓蔚; 黄小锋; 张验科

    2011-01-01

    By the theory of ecological carrying capacity (ECC) based on ecosystem health, evaluation indices and assessing standards for the ECC impact caused by cascade hydropower development were proposed. A corresponding evaluation model based on the projection pursuit (PP) and immune evolutionary algorithm was established. A case study of the Nujiang River in Yunnan Province shows that all the ECC indices of this area keep increasing at different stages of watershed exploitation. On completion of the planned hydropower development,the synthesis ECC index of this watershed will increase by 8.6%.%基于生态系统健康的生态承载力理念,提出了水电梯级开发对区域生态承载力影响的评价指标体系,建立了基于投影寻踪的评价模型.以怒江州为研究区域,对水电梯级开发对生态承载力的影响进行了深入分析.研究结果表明:怒江中下游水电梯级开发规划实施的不同阶段对怒江州生态承载力均为正面影响.梯级开发规划全面实施后,通过生态承载力的调控,将使怒江州的生态承载力综合特征值上升8.6%.

  7. System Dynamics Simulation of Small Towns' Economy under the Constraints of Water Resources' Carrying Capacity%水资源承载力约束下小城镇经济发展的系统动力学仿真

    Institute of Scientific and Technical Information of China (English)

    卢超; 王蕾娜; 张东山; 张亚雷

    2011-01-01

    With rapid urbanization and serious water scarcity in China, carrying capacity of water resources has become an important factor affecting economic development of small towns. As the main model to simulate complex giant systems, system dynamics seems to be suitable for long-term, dynamic and macro-quantitative analysis and simulation study. According to the theory of system dynamics, exploring and applying the optimal pattern of economic growth under the constraints of water resources is the key for sustainable development. A complete small towns’ sustainable economic system includes seven sub-systems, i.e., water resources, total economic outputs, population, agriculture, industry, service industry, and ecological environment. Based on the theory dissertated above, first the authors analyzed related factors affecting water resources capacity, involving natural factors (water quantity, water quality, development and utilization levels, the availability of water resources and water self-purification capacity, ecological water requirements, and water conservation, etc) and socio-economic factors (economic scale and industrial structure, technological progress and productivity, population and living standards, market conditions, policies, regulations, psychological factors, and other resource potential, etc). Moreover, this study established a system dynamics model for coupling research on water resources and economy of small towns using Vensim PLE. As a result, the largest economic scale, the best industrial structure, and the reasonable population amounts of sustainable development can be analyzed dynamically and forecasted. Furthermore, this study selected Taipusi County, Inner Mongolia Autonomous Region as an example, which is a relative poor and seriously arid small town in middle China. Water resources are the bottleneck restricting the economic and social development of this region. The geographical boundary of this model was the administrative area

  8. BALANCE CAPACITY WITH VARIABILITY CAUSED BY HUMAN FACTOR: AN APPLICATION IN A LINE WITH MONTE CARLO SIMULATION

    Directory of Open Access Journals (Sweden)

    Augusto Sandes Mendes

    2016-07-01

    Full Text Available The variation in processing times due to the human factor between the working stations of a production line can generate queues resulting in a higher cost to the productive process. The objective of this study was to apply Monte Carlo simulation to balance the capacity of a production line with stations suffering variability in processing time due to the human factor. Simulations of the current situation of the production line were performed by comparing it with a proposal to align capacity with the production restriction in order to reduce inventories process while maintaining full capacity of the line. To develop the study, the selection involves the case of a company’s production line in the metal industry that produces machinery and products for metalworking area. The results allowed pointing suggestions for the company to reduce in-process inventory, keeping then total capacity of the line.

  9. Design and evaluation on the indicator system of land comprehensive carrying capacity%土地综合承载力指标体系设计及评价——中国东部沿海地区案例研究

    Institute of Scientific and Technical Information of China (English)

    王书华; 毛汉英

    2001-01-01

    In recent years,eastern China has made great progress in economy.But with its rapid development,man land conflicts have become more and more serious. This paper,based on the review land carrying capacity,constructs a set of indicator system for comprehensive evaluation of regional land carrying capacity that can be adapted to eastern China. More over,by the use of a certain mathematical method,we can divide this region into three types according to the carrying capacity: the lower level carrying capacity subregion;the mid level carrying capacity subregion;and the higher level carrying capacity subregion. All these types stand for three steps of succession to the land carrying capacity,that is,from the harmonious step at lower level,imbalance step at middle level to the harmonious step of the advanced system.%论文在对土地承载力进行简要回顾的基础上,构建了一套适合于东部沿海地区的区域土地承载力综合评价指标体系,并运用均方差权数决策法,将该区土地承载力划分为3种类型区,即:低承载力区、中等承载力区、高承载力区,分别代表土地承载力演替从低层次的均衡发展阶段较高层次的不均衡发展阶段高层次的系统协调均衡发展阶段。

  10. 全国资源环境承载能力监测预警(2014版)学术思路与总体技术流程%Academic Thought and Technical Progress of Monitoring and Early-warning of the National Resources and Environment Carrying Capacity (V 2014)

    Institute of Scientific and Technical Information of China (English)

    樊杰; 王亚飞; 汤青; 周侃

    2015-01-01

    It is an innovative work of comprehensive deepening reforms of China to establish the mechanism of monitoring and early-warning of carrying capacity. Based on the scientific connotation of the carrying capacity of national resources and environment and oriented to regional sustainable development, this article explores the“pressure-state-response”process of the interaction between the carrying body: the natural foundation (which consists of resources, environment, ecology and disasters) with the carrying object:the human produc-tion and life activities, and presents the academic thought that the early-warning of the national resources and environment carrying capacity is an overload early-warning according to the cap of the constraints of resources and environment or the population and economic rational scales or other key thresholds, and also presents a process early-warning in terms of the changes of the natural basic conditions or the tendencies of the impact of resource utilization and environmental changes. According to the exploration on the principles of early-warn-ing carrying capacity, this article constructs the differential indicator system and the overall technical process of early-warning of marine and terrestrial resources and environment carrying capacity. Land resources stress index, water resources use intensity index, environmental stress strength index and vegetation coverage change range index are chosen as basic indicators to conduct an overall regional evaluation, and different specific indi-cators, such as the pollution level of dust-haze, the increase and decrease of arable land, equilibrium index of grass and livestock and the variation of eco-environmental quality, are chosen to conduct the specific evalua-tion respectively for the urbanized areas, major grain producing areas, pastoral and semi-pastoral areas and eco-logical function areas, and then the key thresholds of these indicators are determined to conduct classifying evaluation

  11. Serrumab: a novel human single chain-fragment antibody with multiple scorpion toxin-neutralizing capacities.

    Science.gov (United States)

    Pucca, Manuela Berto; Cerni, Felipe Augusto; Peigneur, Steve; Arantes, Eliane Candiani; Tytgat, Jan; Barbosa, José Elpidio

    2014-01-01

    In Brazil, scorpion envenomation is an important public health problem. The yellow scorpion, Tityus serrulatus (Ts), is considered the most dangerous species in the country, being responsible for the most severe clinical cases of envenomation. Currently, the administration of serum produced in horses is recognized and used as a treatment for accidents with scorpions. However, horse herds' maintenance is costly and the antibodies are heterologous, which can cause anaphylaxis and Serum Sickness. In the present work, a human monoclonal fragment antibody, Serrumab, has been analysed. Toxin neutralizing effects of Serrumab were evaluated using a two-electrode voltage-clamp technique. The results show that Serrumab presented a high neutralizing effect against Ts β-toxins (Ts1, 43.2% and Ts2, 68.8%) and none or low neutralizing effect against α-toxins (Ts3, 0% and Ts5, 10%). Additional experiments demonstrated that Serrumab was also able to neutralize the action of toxins from other scorpion genus (Css II, 45.96% and Lqh III, 100%/β- and α-toxins, respectively). This work indicated that Serrumab is able to neutralize many toxins in Ts venom, and could being considered as a neutralizing antibody for formulating a human anti-scorpion serum in Brazil. Additionally, this work demonstrated that Serrumab could neutralize different toxins from distinct scorpion genus. All these results reinforce the idea that Serrumab is a scFv antibody with multiple neutralizing capacities and a promising candidate for inclusion in scorpion anti-venoms against different genera.

  12. High levels of SOX5 decrease proliferative capacity of human B cells, but permit plasmablast differentiation.

    Directory of Open Access Journals (Sweden)

    Mirzokhid Rakhmanov

    Full Text Available Currently very little is known about the differential expression and function of the transcription factor SOX5 during B cell maturation. We identified two new splice variants of SOX5 in human B cells, encoding the known L-SOX5B isoform and a new shorter isoform L-SOX5F. The SOX5 transcripts are highly expressed during late stages of B-cell differentiation, including atypical memory B cells, activated CD21low B cells and germinal center B cells of tonsils. In tonsillar sections SOX5 expression was predominantly polarized to centrocytes within the light zone. After in vitro stimulation, SOX5 expression was down-regulated during proliferation while high expression levels were permissible for plasmablast differentiation. Overexpression of L-SOX5F in human primary B lymphocytes resulted in reduced proliferation, less survival of CD138neg B cells, but comparable numbers of CD138+CD38hi plasmablasts compared to control cells. Thus, our findings describe for the first time a functional role of SOX5 during late B cell development reducing the proliferative capacity and thus potentially affecting the differentiation of B cells during the germinal center response.

  13. Differential capacity of chaperone-rich lysates in cross-presenting human endogenous and exogenous melanoma differentiation antigens.

    Science.gov (United States)

    Bleifuss, Elke; Bendz, Henriette; Sirch, Birgit; Thompson, Sylvia; Brandl, Anna; Milani, Valeria; Graner, Michael W; Drexler, Ingo; Kuppner, Maria; Katsanis, Emmanuel; Noessner, Elfriede; Issels, Rolf-Dieter

    2008-12-01

    The goal of immune-based tumor therapies is the activation of immune cells reactive against a broad spectrum of tumor-expressed antigens. Vaccines based on chaperone proteins appear promising as these proteins naturally exist as complexes with various protein fragments including those derived from tumor-associated antigens. Multi-chaperone systems are expected to have highest polyvalency as different chaperones can carry distinct sets of antigenic fragments. A free-solution isoelectric focusing (FS-IEF) technique was established to generate chaperone-rich cell lysates (CRCL). Results from murine systems support the contention that CRCL induce superior anti-tumor responses than single chaperone vaccines. We established an in vitro model for human melanoma to evaluate the capacity of CRCL to transfer endogenously expressed tumor antigens to the cross-presentation pathway of dendritic cells (DC) for antigen-specific T cell stimulation. CRCL prepared from human melanoma lines contained the four major chaperone proteins Hsp/Hsc70, Hsp90, Grp94/gp96 and calreticulin. The chaperones within the melanoma cell-derived CRCL were functionally active in that they enhanced cross-presentation of exogenous peptides mixed into the CRCL preparation. Superior activity was observed for Hsp70-rich CRCL obtained from heat-stressed melanoma cells. Despite the presence of active chaperones, melanoma cell-derived CRCL failed to transfer endogenously expressed melanoma-associated antigens to DC for cross-presentation and cytotoxic T cell (CTL) recognition, even after increasing intracellular protein levels of tumor antigen or chaperones. These findings reveal limitations of the CRCL approach regarding cross-presentation of endogenously expressed melanoma-associated antigens. Yet, CRCL may be utilized as vehicles to enhance the delivery of exogenous antigens for DC-mediated cross-presentation and T cell stimulation.

  14. Decreased mitochondrial oxidative phosphorylation capacity in the human heart with left ventricular systolic dysfunction

    DEFF Research Database (Denmark)

    Stride, Nis; Larsen, Steen; Hey-Mogensen, Martin

    2013-01-01

    Heart failure (HF) with left ventricular systolic dysfunction (LVSD) is associated with a shift in substrate utilization and a compromised energetic state. Whether these changes are connected with mitochondrial dysfunction is not known. We hypothesized that the cardiac phenotype in LVSD could...... be caused by reduced mitochondrial oxidative phosphorylation (OXPHOS) capacity and reduced mitochondrial creatine kinase (miCK) capacity. The study aim was to test mitochondrial OXPHOS capacity in LVSD myocardium compared with OXPHOS capacity in a comparable patient group without LVSD....

  15. The capacity of the human iliotibial band to store elastic energy during running.

    Science.gov (United States)

    Eng, Carolyn M; Arnold, Allison S; Lieberman, Daniel E; Biewener, Andrew A

    2015-09-18

    The human iliotibial band (ITB) is a poorly understood fascial structure that may contribute to energy savings during locomotion. This study evaluated the capacity of the ITB to store and release elastic energy during running, at speeds ranging from 2-5m/s, using a model that characterizes the three-dimensional musculoskeletal geometry of the human lower limb and the force-length properties of the ITB, tensor fascia lata (TFL), and gluteus maximus (GMax). The model was based on detailed analyses of muscle architecture, dissections of 3-D anatomy, and measurements of the muscles' moment arms about the hip and knee in five cadaveric specimens. The model was used, in combination with measured joint kinematics and published EMG recordings, to estimate the forces and corresponding strains in the ITB during running. We found that forces generated by TFL and GMax during running stretch the ITB substantially, resulting in energy storage. Anterior and posterior regions of the ITB muscle-tendon units (MTUs) show distinct length change patterns, in part due to different moment arms at the hip and knee. The posterior ITB MTU likely stores more energy than the anterior ITB MTU because it transmits larger muscle forces. We estimate that the ITB stores about 1J of energy per stride during slow running and 7J during fast running, which represents approximately 14% of the energy stored in the Achilles tendon at a comparable speed. This previously unrecognized mechanism for storing elastic energy may be an adaptation to increase human locomotor economy.

  16. Heat Capacity Changes for Transition-State Analogue Binding and Catalysis with Human 5'-Methylthioadenosine Phosphorylase.

    Science.gov (United States)

    Firestone, Ross S; Cameron, Scott A; Karp, Jerome M; Arcus, Vickery L; Schramm, Vern L

    2017-02-17

    Human 5'-methylthioadenosine phosphorylase (MTAP) catalyzes the phosphorolysis of 5'-methylthioadenosine (MTA). Its action regulates cellular MTA and links polyamine synthesis to S-adenosylmethionine (AdoMet) salvage. Transition state analogues with picomolar dissociation constants bind to MTAP in an entropically driven process at physiological temperatures, suggesting increased hydrophobic character or dynamic structure for the complexes. Inhibitor binding exhibits a negative heat capacity change (-ΔCp), and thus the changes in enthalpy and entropy upon binding are strongly temperature-dependent. The ΔCp of inhibitor binding by isothermal titration calorimetry does not follow conventional trends and is contrary to that expected from the hydrophobic effect. Thus, ligands of increasing hydrophobicity bind with increasing values of ΔCp. Crystal structures of MTAP complexed to transition-state analogues MT-DADMe-ImmA, BT-DADMe-ImmA, PrT-ImmA, and a substrate analogue, MT-tubercidin, reveal similar active site contacts and overall protein structural parameters, despite large differences in ΔCp for binding. In addition, ΔCp values are not correlated with Kd values. Temperature dependence of presteady state kinetics revealed the chemical step for the MTAP reaction to have a negative heat capacity for transition state formation (-ΔCp(‡)). A comparison of the ΔCp(‡) for MTAP presteady state chemistry and ΔCp for inhibitor binding revealed those transition-state analogues most structurally and thermodynamically similar to the transition state. Molecular dynamics simulations of MTAP apoenzyme and complexes with MT-DADMe-ImmA and MT-tubercidin show small, but increased dynamic motion in the inhibited complexes. Variable temperature CD spectroscopy studies for MTAP-inhibitor complexes indicate remarkable protein thermal stability (to Tm = 99 °C) in complexes with transition-state analogues.

  17. Molecular, physiological, and motor performance defects in DMSXL mice carrying >1,000 CTG repeats from the human DM1 locus.

    Directory of Open Access Journals (Sweden)

    Aline Huguet

    Full Text Available Myotonic dystrophy type 1 (DM1 is caused by an unstable CTG repeat expansion in the 3'UTR of the DM protein kinase (DMPK gene. DMPK transcripts carrying CUG expansions form nuclear foci and affect splicing regulation of various RNA transcripts. Furthermore, bidirectional transcription over the DMPK gene and non-conventional RNA translation of repeated transcripts have been described in DM1. It is clear now that this disease may involve multiple pathogenic pathways including changes in gene expression, RNA stability and splicing regulation, protein translation, and micro-RNA metabolism. We previously generated transgenic mice with 45-kb of the DM1 locus and >300 CTG repeats (DM300 mice. After successive breeding and a high level of CTG repeat instability, we obtained transgenic mice carrying >1,000 CTG (DMSXL mice. Here we described for the first time the expression pattern of the DMPK sense transcripts in DMSXL and human tissues. Interestingly, we also demonstrate that DMPK antisense transcripts are expressed in various DMSXL and human tissues, and that both sense and antisense transcripts accumulate in independent nuclear foci that do not co-localize together. Molecular features of DM1-associated RNA toxicity in DMSXL mice (such as foci accumulation and mild missplicing, were associated with high mortality, growth retardation, and muscle defects (abnormal histopathology, reduced muscle strength, and lower motor performances. We have found that lower levels of IGFBP-3 may contribute to DMSXL growth retardation, while increased proteasome activity may affect muscle function. These data demonstrate that the human DM1 locus carrying very large expansions induced a variety of molecular and physiological defects in transgenic mice, reflecting DM1 to a certain extent. As a result, DMSXL mice provide an animal tool to decipher various aspects of the disease mechanisms. In addition, these mice can be used to test the preclinical impact of systemic

  18. Molecular, physiological, and motor performance defects in DMSXL mice carrying >1,000 CTG repeats from the human DM1 locus.

    Science.gov (United States)

    Huguet, Aline; Medja, Fadia; Nicole, Annie; Vignaud, Alban; Guiraud-Dogan, Céline; Ferry, Arnaud; Decostre, Valérie; Hogrel, Jean-Yves; Metzger, Friedrich; Hoeflich, Andreas; Baraibar, Martin; Gomes-Pereira, Mário; Puymirat, Jack; Bassez, Guillaume; Furling, Denis; Munnich, Arnold; Gourdon, Geneviève

    2012-01-01

    Myotonic dystrophy type 1 (DM1) is caused by an unstable CTG repeat expansion in the 3'UTR of the DM protein kinase (DMPK) gene. DMPK transcripts carrying CUG expansions form nuclear foci and affect splicing regulation of various RNA transcripts. Furthermore, bidirectional transcription over the DMPK gene and non-conventional RNA translation of repeated transcripts have been described in DM1. It is clear now that this disease may involve multiple pathogenic pathways including changes in gene expression, RNA stability and splicing regulation, protein translation, and micro-RNA metabolism. We previously generated transgenic mice with 45-kb of the DM1 locus and >300 CTG repeats (DM300 mice). After successive breeding and a high level of CTG repeat instability, we obtained transgenic mice carrying >1,000 CTG (DMSXL mice). Here we described for the first time the expression pattern of the DMPK sense transcripts in DMSXL and human tissues. Interestingly, we also demonstrate that DMPK antisense transcripts are expressed in various DMSXL and human tissues, and that both sense and antisense transcripts accumulate in independent nuclear foci that do not co-localize together. Molecular features of DM1-associated RNA toxicity in DMSXL mice (such as foci accumulation and mild missplicing), were associated with high mortality, growth retardation, and muscle defects (abnormal histopathology, reduced muscle strength, and lower motor performances). We have found that lower levels of IGFBP-3 may contribute to DMSXL growth retardation, while increased proteasome activity may affect muscle function. These data demonstrate that the human DM1 locus carrying very large expansions induced a variety of molecular and physiological defects in transgenic mice, reflecting DM1 to a certain extent. As a result, DMSXL mice provide an animal tool to decipher various aspects of the disease mechanisms. In addition, these mice can be used to test the preclinical impact of systemic therapeutic

  19. 轴压加筋壁板承载能力计算方法探讨%Investigation of the Computing Methods to Calculate Load-carrying Capacity of Stiffened Panels under Axial Compression

    Institute of Scientific and Technical Information of China (English)

    王海燕; 童贤鑫

    2012-01-01

    Currently, engineering method is usually used to compute the load carrying capacity of the panels in a design process. In this paper, three major engineering methods are briefly described and investigated. These methods are evaluated through the comparison of calculated results and test data, for the stiffed panels of the central wing and fuselage of an aircraft. It is shown that the results from ultimate load method are safer and more consistent with the experimental data. The reasonable allowable stress for central wing of the aircraft is specified according to the previous comparisons and analysis. Finally, eleven types of stiffened panels under axi- al compression of the aircraft fuselage are calculated by using ultimate load method. The results agree well with the experimental data. It is approved that this method can meet the requirement more accurately and utility in engineering design.%目前飞机设计中主要采用工程方法计算加筋壁板的承载能力。本文介绍并评述了分段处理法、John-son法和极限载荷法三种常用的工程方法,为了探讨哪种方法能更加满足工程需要,采用这三种方法对某型飞机中央翼加筋壁板及其试验件分别进行计算,表明其中极限载荷法的计算结果偏于安全,与试验结果吻合较好,并采用此法确定了中央翼加筋壁板的承载能力。最后采用极限载荷法进一步计算该型飞机机身11种构型加筋壁板轴压试验件,破坏载荷计算值与试验结果相当吻合,从而证实了极限载荷法是一种计算轴压加筋壁板承载能力更准确、实用的工程方法。

  20. Cupric ion reducing antioxidant capacity assay for antioxidants in human serum and for hydroxyl radical scavengers.

    Science.gov (United States)

    Apak, Reşat; Güçlü, Kubilay; Ozyürek, Mustafa; Bektaşoğlu, Burcu; Bener, Mustafa

    2010-01-01

    Tests measuring the combined antioxidant effect of the nonenzymatic defenses in biological fluids may be useful in providing an index of the organism's capability to counteract reactive species known as pro-oxidants, resist oxidative damage, and combat oxidative stress-related diseases. The selected chromogenic redox reagent for the assay of human serum should be easily accessible, stable, selective, and respond to all types of biologically important antioxidants such as ascorbic acid, alpha-tocopherol, beta-carotene, reduced glutathione (GSH), uric acid, and bilirubin, regardless of chemical type or hydrophilicity. Our recently developed cupric reducing antioxidant capacity (CUPRAC) spectrophotometric method for a number of polyphenols and flavonoids using the copper(II)-neocuproine reagent in ammonium acetate buffer is now applied to a complete series of plasma antioxidants for the assay of total antioxidant capacity of serum, and the resulting absorbance at 450 nm is recorded either directly (e.g., for ascorbic acid, alpha-tocopherol, and glutathione) or after incubation at 50 degrees C for 20 min (e.g., for uric acid, bilirubin, and albumin), quantitation being made by means of a calibration curve. The lipophilic antioxidants, alpha-tocopherol and beta-carotene, are assayed in dichloromethane. Lipophilic antioxidants of serum are extracted with n-hexane from an ethanolic solution of serum subjected to centrifugation. Hydrophilic antioxidants of serum are assayed in the centrifugate after perchloric acid precipitation of proteins. The CUPRAC molar absorptivities, linear ranges, and TEAC (trolox equivalent antioxidant capacity) coefficients of the serum antioxidants are established, and the results are evaluated in comparison with the findings of the ABTS/TEAC reference method. The intra- and inter-assay coefficients of variation (CVs) are 0.7 and 1.5%, respectively, for serum. The CUPRAC assay proved to be efficient for glutathione and thiol-type antioxidants

  1. Comparison of corneal epitheliotrophic capacities among human platelet lysates and other blood derivatives

    Science.gov (United States)

    Huang, Chien-Jung; Sun, Yi-Chen; Christopher, Karen; Pai, Amy Shih-I; Lu, Chia-Ju; Hu, Fung-Rong; Lin, Szu-Yuan; Chen, Wei-Li

    2017-01-01

    Purpose To evaluate the corneal epitheliotropic abilities of two commercialized human platelet lysates (HPLs) and to compare the results with other blood derivatives, including human peripheral serum (HPS) and bovine fetal serum (FBS). Methods In vitro, human corneal epithelial cells were incubated in various concentrations (0%, 3%, 5% and 10%) of blood derivatives. Two commercialized HPLs, including UltraGRO TM (Helios, Atlanta, GA) and PLTMax (Mill Creek, Rochester, MI), were tested and compared with HPS and FBS. Scratch-induced directional wounding assay was performed to evaluate cellular migration. MTS assay was used to evaluate cellular proliferation. Cellular differentiation was examined by scanning electron microscopy, inverted microscopy and transepithelial electrical resistance. Sprague-Dawley rats were used to evaluate the effects of the blood derivatives on corneal epithelial wound healing in vivo. Different blood derivatives were applied topically every 2 hours for 2 days after corneal epithelial debridement. The concentrations of epidermal growth factor (EGF), transforming growth factor -β1 (TGF-β1), fibronectin, platelet-derived growth factor-AB (PDGF-AB), PDGF-BB, and hyaluronic acid in different blood derivatives were evaluated by enzyme-linked immunosorbent assay (ELISA). Results In vitro experiments demonstrated statistically comparable epitheliotropic characteristics in cellular proliferation, migration, and differentiation for the two commercialized HPLs compared to FBS and HPS. Cells cultured without any serum were used as control group. The epitheliotropic capacities were statistically higher in the two commercialized HPLs compared to the control group (p<0.05). Among the different concentrations of blood derivatives, the preparations with 3% yielded better outcomes compared to 5% and 10%. In rats, HPLs also caused improved but not statistically significant wound healing compared to HPS. All the blood derivatives had better wound healing

  2. Ammonia metabolism capacity of HepG2 cells with high expression of human glutamine synthetase

    Institute of Scientific and Technical Information of China (English)

    Nan-Hong Tang; Xiao-Qian Wang; Xiu-Jin Li; Yan-Ling Chen

    2008-01-01

    BACKGROUND:Currently, one of the tough problems for the application of bioartiifcial liver (BAL) is the shortage of suitable hepatocytes. There are reports on different types of BAL assistance developed with porcine hepatocytes and HepG2 C3A cells, but their defects are obvious. In recent years, some studies focus more on liver cells with features of human origin and improved detoxiifcation. In this study, a hepatocyte line with high expression of human glutamine synthetase (hGS) was raised and its capacity for ammonia metabolism was investigated. METHODS:hGS cDNA and alpha-fetoprotein transcription regulatory element (AFP-TRE) were cloned with the designed primers. The eukaryotic expression vectors, pLNChGS and pLNAFhGS, were constructed and transfected into PA317 cells. Recombinant retroviruses (Retro-hGS and Retro-AFhGS) were produced and then infected into HepG2 cells. G418-resistant cell clones, HepG2/pLNChGS and HepG2/pLNAFhGS, were selected and ampliifed. Then hGS mRNA was measured by semi-quantitative RT-PCR;hGS enzymatic activity and ammonia metabolism analysis in different concentration of NH4+were detected with a quantitative biochemistry kit. The cell proliferation was also detected by MTT chromatometry. RESULTS:The expression of hGS mRNA in HepG2/pLNChGS cells (8.306±0.336) and HepG2/pLNAFhGS cells (21.358±1.716) was much stronger than in control cells (P CONCLUSION:The constructed hepatocytes (HepG2 cells) with speciifc high-expression of hGS have a powerful ability to degrade ammonia in vitro, and provide necessary experimental data for the selection of biomaterials in BAL.

  3. Characterization of IncN plasmids carrying blaCTX-M-1 and qnr genes in Escherichia coli and Salmonella from animals, the environment and humans

    DEFF Research Database (Denmark)

    Dolejska, Monika; Villa, Laura; Hasman, Henrik;

    2013-01-01

    and ST8, respectively. Related plasmids circulating in human and animal isolates were identified. Complete nucleotide sequences of the ST1 pHHA45 plasmid carrying blaCTX-M-1, isolated from E. coli from pigs in Denmark, and the ST3 pKT58A plasmid harbouring qnrS1, identified in E. coli from a water bird......Objectives The aim of the study was to characterize a collection of Escherichia coli and Salmonella harbouring qnr and blaCTX-M-1 genes on IncN plasmids isolated from humans, food-producing, companion and wild animals, and the environment from six European countries.Methods Nineteen IncN plasmids...... DNA purified from the respective E. coli transformants.Results Three types of IncN plasmids carrying blaCTX-M-1, qnrS1 and qnrB19 genes were identified in strains isolated from the Czech Republic, Poland, Slovakia, Denmark, Italy and the Netherlands, corresponding to pMLST sequence type (ST) 1, ST3...

  4. Wine pH Prevails over Buffering Capacity of Human Saliva.

    Science.gov (United States)

    Obreque-Slier, Elías; Espínola-Espínola, Valeria; López-Solís, Remigio

    2016-11-02

    Wine is an acidic beverage; its pH (2.9-3.8) is critically important to its organoleptic properties. During degustation, wine interacts with wine and thus its sensorial properties. In this study both in vitro and in vivo approaches were conducted to measure pH in mixtures of representative red and white wines with human saliva. Continuous additions of microvolumes of either wine to a definite volume (3 mL) of saliva in vitro resulted in a progressive and steep decline in the pH of the wine/saliva mixture. Thus, a few microliters of either wine (wine to saliva lowered the pH to that of the corresponding wine. In the in vivo assay, definite volumes (1.5-18 mL) of either wine were mixed for 15 s with the mouth saliva of individual healthy subjects before pH determination in the expectorated wine/saliva mixtures. Compared to saliva, pronounced decreases in pH were observed, thus approaching the pH of wine even with the smallest volume of wine in the assay. Altogether, these results demonstrate that the buffering capacity of wine prevails over that of saliva and that during degustation the pH of the wine/saliva mixture in the mouth is, at least temporarily, that of the corresponding wine.

  5. In vitro catabolism of rutin by human fecal bacteria and the antioxidant capacity of its catabolites.

    Science.gov (United States)

    Jaganath, Indu B; Mullen, William; Lean, Michael E J; Edwards, Christine A; Crozier, Alan

    2009-10-15

    The role of colonic microflora in the breakdown of quercetin-3-O-rutinoside (rutin) was investigated. An in vitro fermentation model was used and (i) 28 micromol of rutin and (ii) 55 micromol of quercetin plus 18 x 10(6) dpm of [4-(14)C]quercetin (60 nmol) were incubated with fresh fecal samples from three human volunteers, in the presence and absence of glucose. The accumulation of quercetin during in vitro fermentation demonstrated that deglycosylation is the initial step in the breakdown of rutin. The subsequent degradation of quercetin was dependent upon the interindividual composition of the bacterial microflora and was directed predominantly toward the production of either hydroxyphenylacetic acid derivatives or hydroxybenzoic acids. Possible catabolic pathways for these conversions are proposed. The presence of glucose as a carbon source stimulated the growth and production of bacterial microflora responsible for both the deglycosylation of rutin and the catabolism of quercetin. 3,4-Dihydroxyphenylacetic acid accumulated in large amounts in the fecal samples and was found to possess significant reducing power and free radical scavenging activity. This catabolite may play a key role in the overall antioxidant capacity of the colonic lumen after the ingestion of quercetin-rich foods.

  6. Artificial and Natural Sialic Acid Precursors Influence the Angiogenic Capacity of Human Umbilical Vein Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Sebastian P. Galuska

    2013-02-01

    Full Text Available N-acetylneuraminic acid (Neu5Ac represents the most common terminal carbohydrate residue in many mammalian glycoconjugates and is directly involved in a number of different physiological as well as pathological cellular processes. Endogenous sialic acids derive from the biosynthetic precursor molecule N-acetyl-D-mannosamine (ManNAc. Interestingly, N-acyl-analogues of D-mannosamine (ManN can also be incorporated and converted into corresponding artificial sialic acids by eukaryotic cells. Within this study, we optimized a protocol for the chemical synthesis of various peracetylated ManN derivatives resulting in yields of approximately 100%. Correct molecular structures of the obtained products ManNAc, N-propanoyl-ManN (ManNProp and N-butyl-ManN (ManNBut were verified by GC-, ESI-MS- and NMR-analyses. By applying these substances to human umbilical vein endothelial cells (HUVECs, we could show that each derivative was metabolized to the corresponding N-acylneuraminic acid variant and subsequently incorporated into nascent glycoproteins. To investigate whether natural and/or artificial sialic acid precursors are able to modulate the angiogenic capacity of HUVECs, a spheroid assay was performed. By this means, an increase in total capillary length has been observed when cells incorporated N-butylneuraminic acid (Neu5But into their glycoconjugates. In contrast, the natural precursor ManNAc inhibited the growth of capillaries. Thus, sialic acid precursors may represent useful agents to modulate blood vessel formation.

  7. Work capacity and metabolic and morphologic characteristics of the human quadriceps muscle in response to unloading

    Science.gov (United States)

    Berg, H. E.; Dudley, G. A.; Hather, B.; Tesch, P. A.

    1993-01-01

    The response of skeletal muscle to unweighting was studied in six healthy males who were subjected to four weeks of lowerlimb suspension. They performed three bouts of 30 consecutive maximal concentric knee extensions, before unloading and the day after (POST 1), 4 days after (POST 2) and 7 weeks after (REC) resumed weight-bearing. Peak torque of each contraction was recorded and work was calculated as the mean of the average peak torque for the three bouts and fatigability was measured as the decline in average peak torque over bouts. Needle biopsies were obtained from m. vastus lateralis of each limb before and at POST 1. Muscle fibre type composition and area, capillarity and the enzyme activities of citrate synthase (CS) and phosphofructokinase (PFK) were subsequently analysed. Mean average peak torque for the three bouts at POST1, POST2 and REC was reduced (P 0.05) in response to unloading. The activity of CS, but not PFK, decreased (P < 0.05) after unloading. The weight-bearing limb showed no changes in the variables measured. The results of this study suggest that this human lowerlimb suspension model produces substantial impairments of work and oxidative capacity of skeletal muscle. The performance decrements are most likely induced by lack of weight-bearing.

  8. The targeted inhibitory effects of human amniotic fluid stem cells carrying CXCR4 promoter and DAL-1 on non-small cell lung carcinoma growth.

    Science.gov (United States)

    Li, L; Li, S; Cai, T; Wang, H; Xie, X; Liu, Z; Zhang, Y

    2016-02-01

    The differentially expressed in adenocarcinoma of the lung-1 (DAL-1) protein has been demonstrated to be suppressive to various types of tumors including lung cancer. This study aimed to determine the targeted effects of human amniotic fluid stem cells (hAFS cells) carrying CXCR4 promoter driven conditionally repli