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Can rarefaction be used to estimate song repertoire size in birds？

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Current Zoology 2011年第3期57卷 300-306页

作者： kathleen R. PESHEK Daniel T. BLUMSTEIN The Rocky Mountain Biological Laboratory Box 519 Crested Butte CO 81224 USA Department of Ecology and Evolutionary Biology University of California Los Angeles CA 90095-1606 USA

Song repertoire size is the number of distinct syllables, phrases, or song types produced by an individual or population. Repertoire size estimation is particularly difficult for species that produce highly variable songs and those that produce many song types. Estimating repertoire size is important for ecological and evolutionary studies of speciation, studies of sexual selection, as well as studies of how species may adapt their songs to various acoustic environments. There are several methods to estimate repertoire size, however prior studies discovered that all but a full numerical count of song types might have substantial inaccuracies associated with them. We evaluated a somewhat novel approach to estimate repertoire size--rarefaction; a technique ecologists use to measure species diversity on individual and population levels. Using the syllables within American robins＇ Turdus migratorius repertoire, we compared the most commonly used techniques of estimating repertoires to the results of a rarefaction analysis. American robins have elaborate and unique songs with few syllables shared between individuals, and there is no evidence that robins mimic their neighbors. Thus, they are an ideal system in which to compare techniques. We found that the rarefaction technique results resembled that of the numerical count, and were better than two alternative methods （behavioral accumulation curves, and capture-recapture） to estimate syllable repertoire size. Future estimates of repertoire size, particularly in vocally complex species, may benefit from using rarefaction techniques when numerical counts are unable to be performed [Current Zoology 57 （3）： 300-306, 2011].

关键词： Behavioral accumulation curve Bioacoustics Capture-recapture Numerical count Rarefaction Song repertoire size

Evolution of IPv6 Internet topology with unusual sudden changes

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Chinese Physics B 2013年第7期22卷 602-609页

作者：艾均赵海 kathleen M. Carley 苏湛李辉 College of Information Science and Engineering Northeastern University Institute for Software Research Carnegie Mellon University

The evolution of Internet topology is not always smooth but sometimes with unusual sudden changes. Consequently, identifying patterns of unusual topology evolution is critical for Internet topology modeling and simulation. We analyze IPv6 Internet topology evolution in IP-level graph to demonstrate how it changes in uncommon ways to restructure the Internet. After evaluating the changes of average degree, average path length, and some other metrics over time, we find that in the case of a large-scale growing the Internet becomes more robust; whereas in a top–bottom connection enhancement the Internet maintains its efficiency with links largely decreased.

关键词： scale-free network Internet topology evolution unusual evolution of Internet topology complex network analysis

Adrenomedullin and endocrine control of immune cells during pregnancy

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Cellular & Molecular Immunology 2014年第5期11卷 456-459页

作者： Brooke C Matson kathleen M Caron Departments of Cell Biology & Physiology University of North Carolina at Chapel Hill Chapel Hill NC USA Genetics University of North Carolina at Chapel Hill Chapel Hill NC USA

The immunology of pregnancy is complex and incompletely understood. Aberrant immune activity in the decidua and in the placenta is believed to play a role in diseases of pregnancy, such as infertility, miscarriage, fetal growth restriction and preeclampsia. Here, we briefly review the endocrine control of uterine natural killer cell populations and their functions by the peptide hormone adrenomedullin. Studies in genetic animal models have revealed the critical importance of adrenomedullin dosage at the maternal-fetal interface, with cells from both the maternal and fetal compartments contributing to essential aspects underlying appropriate uterine receptivity, implantation and vascular remodeling of spiral arteries. These basic insights into the crosstalk between the endocrine and immune systems within the maternal- fetal interface may ultimately translate to a better understanding of the functions and consequences of dysregulated adrenomedullin levels in clinically complicated pregnancies.

关键词： adrenomedullin preeclampsia pregnancy spiral artery remodeling uNK cells

Increased locomotor activity in estrogen-treated ovariectomized rats is associated with nucleus accumbens dopamine and is not reduced by dietary sodium deprivation

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Integrative Zoology 2018年第6期13卷 783-794页

作者： Enith ESPINOSA kathleen S.CURTIS Oklahoma State University-Center for Health Sciences TulsaOklahomaUSA

Estrogens are well known to increase locomotor activity in laboratory rodents;however,the underlying mechanism remains *** used voluntary wheel running by female rats as an index of locomotor behavior to investigate this *** first determined whether the estrogen-induced increase in locomotion was susceptible to inhibition by a physiological challenge,and next whether it was associated with dopaminergic activation in the central reward area,nucleus *** rats were given estradiol or the oil vehicle and housed in cages with or without running *** rats were given regular rodent chow for 1 week,a sodium-deficient diet for the next week,and then were returned to a regular diet for another *** the end of the last week,all rats were killed,brains were extracted and dopamine levels in the nucleus accumbens were *** expected,estradiol treatment increased distance ***,dietary sodium deprivation further increased running,but this appeared to be related to experience with wheel running,rather than to sodium deprivation,per *** was greater in the nucleus accumbens of estradiol-treated rats that ran compared to all other ***,the estrogen-induced increase in locomotion is a robust phenomenon that is not inhibited by a body sodium challenge and is associated with elevated levels of dopamine in reward *** findings raise the possibility that the estrogen-induced increase in locomotor activity,which occurs during a hormonal milieu conducive to reproduction,may reflect mate-seeking behavior and,thereby,maximize reproductive success.

关键词： locomotor activity reproductive hormones reward pathways

Eco-districts in France:What tools to ensure goals achievement?

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Science China Earth Sciences 2020年第6期63卷 865-874页

作者： kathleen BOQUET Charline FROITIER Jinhui LI Kaihua XU Xianlai ZENG State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Higher Institute for Environmental Engineering and Management MINES ParisTechParis Cedex 06France GEM Company Limited Shenzhen 518101China

Globally,to build cities and communities more inclusive,safe,resilient and sustainable is one of the most important sustainable development ***-districts in cities emerged as an answer to current global environmental concerns and have been developed in France since the *** objective of this work is to gather operational feedback from sustainable neighborhood projects owners to better understand the key barriers of such projects and how to overcome them.A case study of the eco-district Les Tanneries,Lingolsheim showed that the carbon footprint of each inhabitant annually amounted to 4 tons CO2 equivalent,more than half of the French *** for improvements were clearly identified regarding transports and food carbon *** for energy consumption,social diversity and density reached the level of the eco-districts average.A governance review pointed out some superior practices such as the formalization of a specification requirements handbook,a competition between project management teams,and the use of neighborhood sustainability assessment tools to measure and track changes in *** validated tools and obtained results can be useful in building sustainable cities and even China’s ecological civilization.

关键词： Geography and environment City management Eco-district Sustainability Assessment France

Mechanisms of cancer metastasis to the bone

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Cell Research 2005年第1期15卷 57-62页

作者： Claire B. POLLOCK,kathleen KELLY Cell and Cancer Biology Branch NCI NIH Bethesda MD 20892 USA Cell and Cancer Biology Branch NCI NIH Bethesda MD 20892 USA

Some of the most common human cancers, including breast cancer, prostate cancer, and lung cancer, metastasize with avidity to bone. What is the basis for their preferential growth within the bone microenvironment? Bidirectional interactions between tumor cells and cells that make up bone result in a selective advantage for tumor growth and can lead to bone destruction or new bone matrix deposition. This review discusses our current understanding of the molecu- lar components and mechanisms that are responsible for those interactions.

关键词： cancer bone metastases osteolytic metastasis osteoblastic metastasis.

In vitro production of functional sperm in mice

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Asian Journal of Andrology 2011年第6期13卷 791-792页

作者： kathleen Hwang Dolores J Lamb Scott Department of Urology Baylor College of Medicine Houston TX 77030 USA Scott Department of Urology and Molecular and Cellular Biology Baylor College of Medicine Houston TX 77030 USA Laboratory for Male Reproductive Research and Testing Baylor College of Medicine Houston TX 77030 USA

Spermatogenesis refers to the process by which the production and development of the spermatozoa （the mature male gamete of most sexually reproducing species） occurs. It is a complex, stepwise process of sperm development, taking more than a month depending upon the species involving three specific functional phases： spermatogonial proliferation, meiosis and metamorphosis.1 Investigators have been successful in recreating this process in some species of fish; however, this whole process has never been reproduced in vitro in mammals.

关键词： Spermatogenesis refers production the spermatozoa

Leveraging quasi-periodic orbits for trajectory design in cislunar space

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Astrodynamics 2021年第2期5卷 139-165页

作者： Brian P.McCarthy kathleen C.Howell School of Aeronautics and Astronautics Neil Armstrong Hall of EngineeringWest LafayetteIN47907-2045USA

Incorporating quasi-periodic orbits into the preliminary design process offers a wide range of options to meet mission constraints and address the challenges in a complex trade *** this investigation,linear stability and quasi-periodic orbit family continuation schemes are examined to meet various types of *** in eclipse avoidance and transfer design are examined by leveraging quasi-periodic orbits and their associated hyperbolic manifolds in the lunar *** are transitioned to an ephemeris model to validate that geometries are maintained in higher-fidelity *** the natural dynamical structures associated with quasi-periodic orbits are leveraged,novel trajectory solutions can emerge.

关键词： multi-body dynamical systems quasi-periodic orbits trajectory analysis cislunar trajectory design near rectilinear halo orbit ephemeris dynamical model

Quality of life in elderly heart failure patients

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Journal of Geriatric Cardiology 2006年第4期3卷 227-236页

作者： kathleen L.Grady kathleen Halvey Division of Cardiology Center for Heart Failure Northwestern University Feinberg School of MedicineChicagoIL 60611USA

Quality of life (QOL), as a relevant area of research in the understanding of heart failure (HF) patient outcomes, has been increasingly studied during the last two decades. The purposes of this review article are to (1) describe QOL in older adults with HF, (2)identify and critique research designed to test interventions to improve QOL, (3) identify gaps in the literature, and (4) provide recommendations for future research. Seventeen studies describing QOL in older adults with HF were identified. Elderly HF patient QOL has been reported to be fair to poor and is worse as compared to a healthy control group. Furthermore, there is some evidence that suggests that QOL is better in older adults than younger adults and worse in women (both older and younger) than in men, although these findings are not consistent across studies. Predictors of QOL and its dimensions in older HF patients included demographic, clinical, and psychosocial variables. Sixteen interventional studies were identified that reported QOL as an outcome in older adults. Findings among randomized clinical trials (RCTs) to improve QOL outcomes in elderly HF patients do not allow strong conclusions about the benefits of the interventions. It must be noted, though, that while not all studies reported improvements in QOL (either significant or as a trend),no studies reported deterioration in QOL with randomization to an intervention versus control. These studies were limited by several methodological issues. While there has been some research of QOL in this elderly cohort, it is paramount that we address methodological issues and thereby improve the scientific rigor of our research, continue to explore QOL in elderly HF patients, and design intervention trials for elders at risk for poor QOL.

关键词： heart failure elderly quality of life