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On the minimum cost of an evolutionary strategy response to environment stress

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Journal of Environmental Sciences 2002年第3期14卷 333-338页

作者： LinZS LiBL DepartmentofGeography NanjinNormalUniversityNanjing210097China.E－mail：zslin@*** DepartmentofBiology theUniversityofNewMexicoAlbuquerqueNM87131－1091USA

Two revised drafts about a simple evolution trade off function studied by Mitchell(Mitchell, 2000) were put up first. Considering the complex of the environment, or the nonlinear interaction of the environment and species, we put up two new cost functions:c(u,z)=c 0+c 1u+k(z+az 2)u,u>0;c(u,z)=c 0+c 1u+kz du,u>0,d>0. In the first case, if the environment is adverse to species ( a >0), the region of low stress which is more suitable for the intolerant species is very small, and at the same environment stress z , the tolerant species will pay the more cost than it will paid in the normal environment. However the tolerant species will pay more cost but low strategies in the environment of a nment of a =0 or a >0. In the second case, the results showed that the greater the stress of the environment is, or the more complex the environment is, the lower cost the intolerant species will pay in the region of z nment of high stress, the organisms must possess a higher u , or a better means of mitigating of the stress of environment. Meanwhile in the region d >1, when d decrease, the intolerant species will pays more lower cost of exploiting a habitat in the low stress environment while the tolerant one will pays more lower cost in the high stress environment. This means that scale d describes the selection character of the species system in the evolution process, the smaller the d(d <1) is, the better the selection or the mitigation the system will possesses.

关键词： evolutionary strategy response environment stress

Succinate dehydrogenase in Parkinson＇s disease

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Frontiers in Biology 2017年第3期12卷 175-182页

作者： Mohammad Jodeiri Farshbaf Department of Biology New Mexico State University Las Cruces NM 88003 USA

BACKGROUND： The prevalence of neurodegenerative disorders such as Parkinson＇s disease （PD） is increased by age. Alleviation of their symptoms and protection of normal neurons against degeneration are the main aspects of the researches to establish novel therapeutic strategies. Many studies have shown that mitochondria as the most important organelles in the brain which show impairment in PD models. Succinate dehydrogenase （SDH） as a component of the oxidative phosphorylation system in mitochondria connects Krebs cycle to the electron transport chain. Dysfunction or inhibition of the SDH can trigger mitochondrial impairment and disruption in ATP generation. Excessive in lipid synthesis and induction of the excitotoxicity as inducers in PD are controlled by SDH activity directly and indirectly. On the other hand, mutation in subunits of the SDH correlates with the onset of neurodegenerative disorders. Therefore, SDH could behave as one of the main regulators in neuroprotection. OBJECTIVE： In this review we will consider contribution of the SDH and its related mechanisms in PD. METHODS： Pubmed search engine was used to find published studies from 1977 to 2016. ＂Succinate dehydrogenase＂, ＂lipid and brain＂, ＂mitochondria and Parkinson＇s disease＂ were the main keywords for searching in the engine. RESULTS： Wide ranges of studies （59 articles） in neurodegenerative disorders especially Parkinson＇s disease like genetics of the Parkinson＇s disease, effects of the mutant SDH on cell activity and physiology and lipid alteration in neurodegenerative disorders have been used in this review. CONCLUSION： Mitochondria as key organelles in the energy generation plays crucial roles in PD. ETC complex in this organelle consists four complexes which alteration in their activities cause ROS generation and ATP depletion. Most of complexes are encoded by mtDNA while complex Ⅱ is the only part of the ETC which is encoded by nuclear genome. So, focusing on the SDH and related pathways which

关键词： Parkinson's disease mitochondria succinate dehydrogenase neuroprotection

The Development and Application of CISMOD 1.0, a New Computerized Tool for Designing Wildlife Rainwater Cisterns

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Computational Water, Energy, and Environmental Engineering 2021年第2期10卷 71-81页

作者： Ariel Ortega Dave Menicucci University of nm Albuquerque NM USA Sandia National Labs (retired) Albuquerque NM USA

This article reports on a case study of the research and development of a new tool to assist in the design of rainwater cisterns. A rainwater cistern is a way to improve wildlife habitat because it can be situated in locations that do not have natural water sources, such as streams or wells that can supply water for storage. However, the design and sizing of such a system can be challenging because a number of constantly varying factors must be considered, such as changing precipitation patterns, the evaporative losses from the cistern and animal water consumption. No standardized sizing methodology currently exists for designing wildlife rainwater cisterns. In this article we present a new method for assisting in optimally sizing a rainwater cistern. We discuss how we implemented the quantitative portion of this methodology into a new Excel? model called CISMOD, which we configured for general use by wildlife professionals. We describe the methodology for designing a rainwater cistern based on standard engineering techniques. We then present and discuss our experience in applying the model to design two rainwater cisterns in an area of the Jemez Mountains in northern New Mexico, USA. The CISMOD model and a user manual are available at no cost for wildlife professionals.

关键词： Cistern Wildlife Design Sizing Construction

Testing of Subgrid-Scale Stress Models by Using Results from Direct Numerical Simulations

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Communications in Nonlinear Science and Numerical Simulation 1998年第2期3卷 35-40页

作者： Hongrui GONG (Health Physics Measurement, MS G761 Los Alamos National Laboratory, Los Alamos, nm 87545) Email: gong@lanl.gov Health Physics Measurement MS G761 Los Alamos National Laboratory Los Alamos NM 87545 USA

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ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｕｒｂｕｌｅｎｔｆｌｏｗｌａｒｇｅｅｄｄｉｅｓｄｏｍｉｎａｔｅｔｈｅｐｈｙｓｉｃｓｏｆｔｈｅｆｌｏｗ．Ｍｏｓｔｏｆｔｈｅｔｒａｎｓｐｏｒｔｏｆｍａｓ，ｍｏｍｅｎｔｕｍａｎｄｅｎｅｒｇｙｉｓｄｕｅｔｏｔｈｅｌａｒｇｅｅｄｄ...

关键词： Subgridmodel Large Eddy Simulation

Time series analysis of mantle cycles Part Ⅰ:Periodicities and correlations among seven global isotopic databases

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Geoscience Frontiers 2019年第4期10卷 1305-1326页

作者： Stephen J. Puetz Kent C. Condie Progressive Science Institute HonoluluHI96815USA New Mexico Institute of Mining and Technology SocorroNM87801USA

In this study,seven isotopic databases are presented and analyzed to identify mantle and crustal episodes on a global scale by focusing on periodicity ranging from 70 to 200 million years(Myr).The databases are the largest,or among the largest,compiled for each type of data-with an objective of finding some samples from every region of every continent,to make each database as global as conceivably *** databases contain zircon Lu/Hf isotopic data,whole-rock Sm/Nd isotopic data,U/Pb detrital zircon ages,U/Pb igneous zircon ages,U/Pb non-zircon ages,whole-rock Re/Os isotopic data,and large igneous province *** I of this study focuses on the periodicities of age histograms and geochemical averages developed from the seven databases,via spectral and cross-correlation *** physical cycles often propagate in exact integer multiples of a fundamental cycle,referred to as *** tests show that harmonic geological cycles of^93.5 and^187 Myr have persisted throughout terrestrial history,and the cyclicities are statistically significant for U/Pb igneous zircon ages,U/Pb detrital zircon ages,U/Pb zircon-rim ages,large igneous province ages,meanεHf(t)for all samples,meanεHf(t)values for igneous-only samples,and relative abundance of mafic *** important,cross-correlation analyses show these seven time-series are nearly synchronous(±7 Myr)with a model consisting of periodicities of 93.5 and 187 ***,the similarities between peaks in the 93.5 and 187 Myr mantle cycles and terminal ages of established and suspected superchrons provide a framework for predicting and testing superchron periodicity.

关键词： Zircon Database Isotope Statistical analysis Spectral analysis Cross correlation

Resolvent Estimates and Quantification of Nonlinear Stability

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Acta Mathematica Sinica,English Series 2000年第1期16卷 1-20页

作者： Heinz-Otto Kreiss Jens Lorenz Department of Mathematics UCLALos AngelesCA 90095USA Department of Mathematics and Statistics UNMAlbuquerqueNM 87131USA

The aim of this paper is to clarify the role played by resolvent estimates for nonlinear *** will give examples showing that a large resolvent may lead to a small domain of nonlinear *** other examples the resolvent is large,but the domain of nonlinear stability is completely *** case prevails depends on the details of the problem. We will also show that the size of the resolvent depends in an essential way on the norms that are used.

关键词： Resolvent estimates Nonlinear stability Pseudospectrum Convection-dominated flow

Emission properties of nanolasers during the transition to lasing

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Light(Science & Applications) 2014年第1期3卷 92-99页

作者： Weng W Chow Frank Jahnke Christopher Gies Sandia National Laboratories AlbuquerqueNM 87185-1086USA Institute for Theoretical Physics University of Bremen28334 BremenGermany

This review addresses ongoing discussions involving nanolaser experiments,particularly those related to thresholdless lasing or few-emitter devices.A quantum-optical(quantum-mechanical active medium and radiation field)theory is used to examine the emission properties of nanolasers under different experimental *** active medium is treated as inhomogeneously broadened semiconductor quantum dots embedded in a quantum well,where carriers are introduced via current *** are made between a conventional laser and a nanolaser with a spontaneous emission factor of unity,as well as a laser with only a few quantum dots providing the *** is found that the combined exploration of intensity,coherence time,photon autocorrelation function and carrier spectral hole burning can provide a unique and consistent picture of nanolasers in the new regimes of laser operation during the transition from thermal to coherent ***,by reducing the number of quantum dots in the optical cavity,a clear indication of non-classical photon statistics is observed before the single-quantum-dot limit is reached.

关键词： nanolasers optoelectronics photon statistics quantum light sources quantum optics semiconductor quantum dots thresholdless lasing

Social Computing Unhinged

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Journal of Social Computing 2020年第1期1卷 1-13页

作者： James Evans University of Chicago ChicagoIL 60637and Santa Fe InstituteSanta FeNM 87501USA.

Social computing is ubiquitous and intensifying in the 21st *** used to reference computational augmentation of social interaction through collaborative filtering,social media,wikis,and crowdsourcing,here I propose to expand the concept to cover the complete dynamic interface between social interaction and computation,including computationally enhanced sociality and social science,socially enhanced computing and computer science,and their increasingly complex combination for mutual *** recommends that we reimagine Computational Social Science as Social Computing,not merely using computational tools to make sense of the contemporary explosion of social data,but also recognizing societies as emergent computers of more or less collective intelligence,innovation and *** further proposes we imagine a socially inspired computer science that takes these insights into account as we build machines not merely to substitute for human cognition,but radically complement *** leads to a vision of social computing as an extreme form of human computer interaction,whereby machines and persons recursively combine to augment one another in generating collective intelligence,enhanced knowledge,and other social goods unattainable without each *** the example of science and technology,I illustrate how progress in each of these areas unleash advances in the others and the beneficial relationship between the technology and science of social computing,which reveals limits of sociality and computation,and stimulates our imagination about how they can reach past those limits together.

关键词： social computing complex systems computer supported cooperative work computational social science artificial intelligence human computer interaction human-centered computing

Numerical Modeling of Anisotropic Elastic-Wave Sensitivity Propagation for Optimal Design of Time-Lapse Seismic Surveys

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Communications in Computational Physics 2020年第6期28卷 442-458页

作者： Kai Gao Lianjie Huang Los Alamos National Laboratory Geophysics GroupMS D452Los AlamosNM 87545USA

Reliable subsurface time-lapse seismic monitoring is crucial for many geo-physical applications,such as enhanced geothermal system characterization,geologic carbon utilization and storage,and conventional and unconventional oil/gas reservoir characterization,*** develop an elastic-wave sensitivity propagation method for optimal design of cost-effective time-lapse seismic surveys considering the fact that most of subsurface geologic layers and fractured reservoirs are anisotropic instead of *** anisotropic media,we define monitoring criteria using qP-and qS-wave sensitivity energies after decomposing qP-and qS-wave components from the total elastic-wave sensitivity wavefield using a hybrid time-and frequency-domain *** should therefore be placed at locations with significant qP-and qS-wave sensitivity energies for cost-effective time-lapse seismic monitoring in an anisotropic geology *** numerical modeling results for a modified anisotropic Hess model demonstrate that,compared with the isotropic case,subsurface anisotropy changes the spatial distributions of elastic-wave sensitivity ***,it is necessary to consider subsurface anisotropies when designing the spatial distri-bution of geophones for cost-effective time-lapse seismic *** finding suggests that it is essential to use our new anisotropic elastic-wave sensitivity modeling method for optimal design of time-lapse seismic surveys to reliably monitor the changes in subsurface reservoirs,fracture zones or target monitoring regions.

关键词： Anisotropy elastic-wave sensitivity time-lapse seismic monitoring