A nonlinear ergodic theorem for discrete systems

A theorem concerning the asymptotic behavior of a general class of systems of difference equations is proven. This theorem guarantees the existence of a stable normalized distribution vector, and enables the constructing of a scalar limiting equation for an aggregate variable. This theory is illustrated using an example from population dynamics, a nonlinear size-structured model of competition for a dynamically modeled limiting resource.Supported in the Program in Applied Mathematics at the University of Arizona by the Applied Mathematics and Population Biology/Ecology Divisions of the National Science Foundation under grant No. DMS-8902508. Supported at Cornell University by the US Army Research Office through the Mathematical Sciences Institute, Contract DAAL03-91-C-0027, and by the National Science Foundation through the Biometrics Unit, grant No. DEB-9253570; This work comprises part of the author's dissertation at the University of Arizona, directed by J. M. Cushing     

Phenolic Compounds from the Fruits of Prunus davidiana (Rosaceae) and Their Antioxidant Activities

This research was supported by Cooperative Research Program for Agriculture Science & Technology Development (Project No. PJ014204032019) and the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2020R1A6A3A01100042).     

Modeling insect dispersal and estimating parameters when mark-release techniques may cause initial disturbances

We consider the problem of quantitatively modeling movements of marked flea beetles in cultivated arrays of the cole crop, collards (Brassica oleraceae). Methods for the estimation of temporally and spatially dependent parameters in general dispersal models are outlined and a summary of our findings using these methods with flea beetle data is given.This research was supported in part by the National Science Foundation under NSF # MCS-8205335 and by the U.S. Air Force Office of Scientific Research under contract AFOSR 81-0198. Part of the research was carried out while this author was a Visiting Professor in the Department of Mathematics at Southern Methodist UniversityThis research was supported in part by the National Science Foundation under NSF # DEB-8207117This research was supported in part by the National Science Foundation under NSF # MCS-8200883. Part of the research was carried out while the first and third authors were visitors at the Institute for Computer Applications in Science and Engineering (ICASE), NASA Langley Research Center, Hampton, Virginia which is operated under NASA contracts NAS1-15810 and NAS1-16394     

Mendelian segregation: a choice between “order” and “chaos”

Research supported in part by a US-Israel Binational Science Foundation grant 85-00021 and by NIH grants GM 28016 and GM 10452     

An improved technique of preparing bone-marrow specimens for cytogenetic analysis

Summary Sixty-six bone-marrow specimens, derived from patients with hematological and non-hematological disorders, were processed for cytogenetic analysis. Modifications of various parameters of the standard (direct) culture procedure were investigated and the quality of the preparations determined. As a result of these experiments, an improved culture technique was developed that yielded significantly better quality chromosome preparations. This method is based on a short incubation (25-min) of the bone-marrow specimen, immediately following aspiration, in a solution containing both hypotonic KCl and colcemid and completely omits the use of tissue culture medium. In partial fulfillment of the requirements for the M.Sc. degree (YS) at the Hebrew University, Jerusalem. Supported by grants from The Ber Lemsdorf Foundation for Cancer Research; The Leukemia Research Foundation; and The US-Israel Binational Science Foundation.     

Chromosomal localization of silkworm (Bombyx mori) sericin gene 1 and chymotrypsin inhibitor 13 using fluorescence in situ hybridization

The chromosomal locations of two single-copy genes, Ser-1 and CI-13, in silkworm (Bombyx mori) were detected at the molecular cytogenetics level by fluorescence in situ hybridization in the study. The results showed that Ser-1 is located near the distal end of the 11th linkage group, relatively at the 12.5±1.4 position in pachytene; and that CI-13 has been mapped near the distal end of the 2nd linkage group, relatively at the 8.2±1.2 position in pachytene. Furthermore, their location model map-FISH map on silkworm chromosome was drawn. The FISH technique and its application to silkworm are also discussed in this paper.     

Global analysis of a model of plasmid-bearing,plasmid-free competition in a chemostat

A model of competition between plasmid-bearing and plasmid-free organisms in a chemostat was proposed in a paper of Stephanopoulis and Lapidus. The model was in the form of a system of nonlinear ordinary differential equations. Such models are relevant to commercial production by genetically altered organisms in continuous culture. The analysis there was local (using index arguments). This paper provides a mathematically rigorous analysis of the global asymptotic behavior of the governing equations in the case of uninhibited specific growth rate.Research supported by the National Council of Science, Republic of ChinaResearch supported by National Science Foundation Grant, DMS-9204490Research supported by the Natural Science and Engineering Council of Canada. This author's contribution was made while on research leave visiting the Department of Ecology and Evolutionary Biology at Princeton University. She would especially like to thank Simon Levin for his guidance as well as for providing an exceptional working environment     

Effect of oxygen–glucose deprivation on degranulation and histamine release of mast cells

The purpose of this study was to investigate the effect of oxygen–glucose deprivation (OGD) on degranulation and histamine release of mast cells. Cultured mast cells were exposed to OGD for 1, 2, 4, 8, or 16 h. At 2 h of OGD exposure, the degranulation percentage of mast cells had increased and subsequently showed a progressive further increase, associated with a similar change in lactate dehydrogenase release. Histamine release increased significantly from 1 h of OGD exposure. These results indicate that OGD induces mast cells to degranulate, possibly via a cytotoxic response. This in vitro ischemic model of mast cells might clarify their roles in the pathological processes induced by cerebral ischemia. This project was supported by the National Natural Science Foundation of China (nos. 30371638, 30472013) and the National Basic Research of China (no. 2003CB515400), and partly by the Zhejiang Provincial Natural Science Foundation of China (R303779) and the Zhejiang Provincial Scientific Research Foundations (2004C34002).     

Nuclear energy: Health impact of carbon-14

Summary Estimates are presented on the carbon-14 generation rates in several reactor types and in peaceful nuclear explosions. If the carbon-14 generated in light water reactors is released, the population radiationdose rate it causes initially will be comparable to that resulting from the krypton-85 and tritium generated in these reactors. Because of the long half-life, the radiationdose commitment and thedose rate resulting from the environmental build-up of carbon-14 are considerably larger than those of the two other radionuclides.This work received support from the Program on Science, Technology, and Society at Cornell University, with funds given them by the Sloan Foundation, Inc.     

Cycling in simple genetic systems

We describe the — unexpected — occurrence of stable limit cycles in the two locus, two allele model. No frequency dependence is involved. The cycles are due to the interaction between recombination and natural selection.This work received support from the National Science Foundation and the Research Foundation of the City University of New York     

Socio-bioenergetics and sexual dimorphism in primates

Socio-bioenergetics is presented as a practical method of estimating energy budgets of primates in a social context. Energy budgets are estimated on the basis of behavioral observations and a series of empirical formulae, which consider body weight, activity, and reproductive status. Data on a captive colony of Sykes' monkeys and baboons are incorporated as illustrations of the possible effects of group composition, body size, reproductive status, and activity patterns on energy requirements.Supported by the Wenner-Gren Foundation for Anthropological Research Incorporated and the National Science Foundation Grant GU-1598.     

Changes in social structure and interactions after the introduction of a second group in a free-ranging troop of stumptail macaques (Macaca arctoides): Social relations II

Data on the social changes that occurred after the release of 12 additional stumptails into a free-ranging group are reported here. In spite of the fact that the members of the two groups had known each other for years, that genealogical relatives were re-united and that there were no limitations exerted by spatial conditions and social density, the release produced dramatic increments in aggressive and other social interactions. The resident group's alpha male was killed by two newcomer males, a restructuring of the dominance order took place, and the adult females were found to be important individuals in the re-establishment of stability. Comparisons with group formation and re-introduction experiments conducted in captive rhesus and pigtail macaques were carried out. Research supported by grants from the Behavioral Science Foundation (U. S.), NSF No. GB-42235 and Behavioral Science Foundation.     

Therapy planning and dosimetry for the pion applicator at the Swiss Institute for Nuclear Research (SIN)

Summary At the Swiss Institute for Nuclear Research a 60 beam pion applicator for radiotherapy is under construction. The methods to produce homogeneous dose distributions in arbitrarily shaped volumes is presented, together with details on the activities in therapy planning and dosimetry in view of the use of the applicator for patients.Supported by the Swiss National Science Foundation (grant no. 3.682.-0.75)     

Chemical models of oxidative phosphorylation

Chemical models for coupling oxidation to phosphorylation are summarized and examined both from the standpoint of organic reaction mechanisms and with respect to their relevance to mitochondria and chloroplasts. In order to accelerate the progress of our research in bioenergetics, it is suggested to focus at least as much attention on structural biochemistry as on phenomenological observations of energy-transducing membranes.Supported in part by Public Health Service Research Grant No. GM 19990 from the National Institute of General Medical Sciences and by National Science Foundation Research Grant No. PCM 74-24083 A01     

Microbial activity in biogeochemical gradients – new aspects of research

In April 2004, the German Research Foundation (DFG) and the National Science Foundation (NSF) co‐organized a meeting for US and German junior geoscientists in Washington DC. As an outcome of this Research Conference titled ‘Earth, Fire, Water, Air and Life’, a follow‐up workshop took place in May 2005 at the Eberhard‐Karls University of Tuebingen in Germany. This workshop covered new aspects of research to improve the understanding of steep biogeochemical gradients covering pH changes, redox zones, as well as solute and particulate concentration variations in aqueous systems. Detailed understanding of biogeochemistry in this context delivers new fundamental aspects in interdisciplinary research. Such work is also urgently needed to control ever‐increasing scarcity of water that is to large parts driven by decreasing water quality. Research ideas on gradients in a biogeochemical context that were discussed by a subgroup of biogeochemists during that workshop are summarized and presented here.     

Novel strategies to mine alcoholism-related haplotypes and genes by combining existing knowledge framework

High-throughout single nucleotide polymorphism detection technology and the existing knowledge provide strong support for mining the disease-related haplotypes and genes. In this study, first, we apply four kinds of haplotype identification methods (Confidence Intervals, Four Gamete Tests, Solid Spine of LD and fusing method of haplotype block) into high-throughout SNP genotype data to identify blocks, then use cluster analysis to verify the effectiveness of the four methods, and select the alcoholism-related SNP haplotypes through risk analysis. Second, we establish a mapping from haplotypes to alcoholism-related genes. Third, we inquire NCBI SNP and gene databases to locate the blocks and identify the candidate genes. In the end, we make gene function annotation by KEGG, Biocarta, and GO database. We find 159 haplotype blocks, which relate to the alcoholism most possibly on chromosome 1∼22, including 227 haplotypes, of which 102 SNP haplotypes may increase the risk of alcoholism. We get 121 alcoholism-related genes and verify their reliability by the functional annotation of biology. In a word, we not only can handle the SNP data easily, but also can locate the disease-related genes precisely by combining our novel strategies of mining alcoholism-related haplotypes and genes with existing knowledge framework. Supported by the National Natural Science Foundation of China (Grant Nos. 30570424, 60601010 and 30600367), the National High-Tech Research and Development Program of China, (Grant No.2007AA02Z329), the Key Science and Technology Program of Heilongjiang Province(Grant No.GB03C602-4), Natural Science Foundation of Heilongjiang Province (Grant No. F2008-02), Youth Science Foundation of Harbin Medical University (Grant No. 060045) and Science Foundation of Heilongjiang Province Education Department (Grant Nos. 11531113 and 1152hq28).     

Neurospora glucamylase and a mutant affected in its regulation

Neurospora glucamylase is a glucose-repressible extracellular enzyme. The enzyme was purified to homogeneity and found to have a molecular weight of 82,000 and to release glucose from either maltose or amylose. The rate of glucamylase synthesis increases more than 100-fold when cells are transferred from a glucose-containing medium to a glucose-free medium. Increased production of glucamylase begins within 30 min of the transfer. Glucamylase is rapidly secreted into the medium. A mutant affecting the ability of glucose to repress the synthesis of the glucose-repressible extracellular enzymes glucamylase and invertase has been isolated and studied. The mutant constitutively synthesizes and secretes a glucamylase which is indistinguishable from the wild-type enzyme.Funds for this research were provided by Grant PCM-8011772 from the National Science Foundation and by a grant from the Research Development Fund of The Research Foundation of the State University of New York.     

Histochemical activation of rat-liver lysosomes by dimethyl sulfoxide

Summary The Gomori reaction for acid phosphatase was enhanced by inclusion of dimethyl sulfoxide (DMSO) in reaction media for incubation of cryostat sections of unfixed rat-liver tissue. The reaction was also detectably increased by DMSO in formol-calcium fixed tissue. Enhancment of the Gomori reaction for acid phosphatase by DMSO was reversible.Supported by Grant GB-3817 from the National Science Foundation and by the University Research Coucil and the Cancer Institutional Grant Committee of the University of North Carolina     

中国昆虫学发展透视

2006—2010年5年来,我国昆虫学工作者获得了国家自然科学基金736项、国家科技支撑计划2项19个课题,公益性行业科研专项34项,"973"项目6项;共发表与昆虫有关的学术论文13772篇,其中SCI收录论文2625篇,Science6篇,Nature1篇,PNAS6篇,Annual Review of Entomology1篇,Nature Bioteachnology4篇;获得了国家科技进步奖二等奖13项。本文分析了2006—2010年我国昆虫学研究项目、研究成果在不同昆虫学分支学科和不同研究区域的分布特征,透视了我们昆虫学研究前沿,旨在为制定我国昆虫学未来发展战略提供基础信息。     

Competition between plasmid-bearing and plasmid-free organisms in a chemostat with an inhibitor

A model of competition in the chemostat with an inhibitor is combined with a model of competition in the chemostat between plasmid-bearing and plasmid-free organism to produce a model that more closely approximates the way chemostat-like devices are used in biotechnology. The asymptotic behavior of the solutions of the resulting system of nonlinear differential equations is analyzed as a function of the relevant parameters. The techniques are those of dynamical systems although perturbation techniques are used when the parameter reflecting plasmid-loss is small.Research Supported by National Council of Science, Republic of ChinaResearch Supported by National Science Foundation Grant MCS 9204490