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Fish embryo and juvenile size under hypoxia in the mouth- brooding African cichlid Pseudocrenilabrus multicolor

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Current Zoology 2012年第3期58卷 401-412页

作者： e.e. ReARDON L.J. CHAPMAN Department of Biology McGill University 1205 Dr. Penfield Ave Montreal Quebec H3A 1B 1 Canada Wildlife Conservation Society 2300 Southern Boulevard Bronx NY 10460 USA

We used a field survey and a laboratory rearing experiment to （a） examine response （size and survival） to life-long hypoxia in offspring of the African maternal mouth-brooding cichlid Pseudocrenilabrus multicolor victoriae （Seegers） and （b） explore the degree to which developmental response can be environmentaUy-induced. embryo size metrics were quantified in 9 field populations across a range of dissolved oxygen （DO） concentrations. In the laboratory, first generation （F1） broods of low-DO origin were reared under high or low DO. Brooding period was quantified for the mothers; and egg size, egg metabolic rate and juvenile size-at-release were quantified in their （F2） offspring. The F2 offspring were split and grown for 3 months post-release under high or low DO, and juvenile size and survival were quantified. In the field survey, across stages, embryos from low-DO field populations were shorter and weighed less than embryos from high-DO populations. In the laboratory experi- ment, F2 eggs and juveniles-at-release from mother＇s mouth did not differ in mass, length, survival regardless of development DO environment. However, juveniles diverged in size after leaving mother＇s mouth, exhibiting smaller size when grown under low DO. Size differences in embryo size across field populations and divergence in embryo size after release from the mother＇s mouth support predictions for smaller body size under hypoxia. There was no evidence for negative effects on survival of juveniles after 3 months. Brooding period was 16% shorter in females reared under low DO suggesting that hypoxia may accelerate embryo de- velopment. This work provides insights into how bearer fishes respond to hypoxic stress relative to fishes with no post-spawning parental care; a shorter brooding interval and smaller body size may provide an optimal solution to parent and embryo survival under hypoxia in brooding fishes [Current Zoology 58 （3）： 401-412, 2012].

关键词： African cichlid Lake Victoria Life-history Parental care Dissolved oxygen

Coating of finely dispersed particles by two-fluid nozzle

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Particuology 2018年第3期16卷 80-93页

作者： N. Hampel e. Roydeva A. Buck e. Tsotsas Thermal Process engineering Otto yon Guericke University Universitatsplatz 2 39106 Magdeburg Germany

Particle coatings are used extensively to generate dispersed solids with well-defined properties, e.g., to protect active ingredients, with most coating processes using core particles of a diameter larger than 200 μm. This work contributes to the development of a coating process for fine dispersed particles （diam- eter less than 50 μm） by combining two particle-formulation processes, namely, coating and spray drying. The feasibility of the operation is based on and demonstrated by the innovative application of a two-fluid nozzle. experiments were conducted by using glass particles as core particles and sodium benzoate as the coating agent. The coating of finely dispersed particles is achieved by the spraying of particles and coating solution as a homogeneous suspension. The aim is to create droplets with only one contained particle at the nozzle outlet. After evaporation of the water in the droplet, a thin solid film is built on the particle surface. The suspension viscosity was measured and compared with empirical equations from the literature. The liquid-film thickness on the particle surface was calculated to predict the building of a uniform coating layer or agglomerates. In this study, the feasibility of pneumatic transport through the nozzle and an investigation of the process were illustrated. The agglomeration fraction and degree of coating of the particle surface were analyzed optically by scanning electron microscopy. In this way, the influence of different processes and suspension parameters on the product quality were determined.

关键词： Coating Spray drying Fine dispersed particle Two-fluid nozzle

Metal-containing nanomaterials as lubricant additives: State-of-the-art and future development

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Friction 2019年第2期7卷 93-116页

作者： Igor e.UFLYAND Vladimir A.ZHINZHILO Victoria e.BURLAKOVA Department of Chemistry Southern Federal University Department of Chemistry Don State Technical University

This review focuses on the effect of metal-containing nanomaterials on tribological performance in oil lubrication. The basic data on nanolubricants based on nanoparticles of metals, metal oxides, metal sulfides, nanocomposities, and rare-earth compounds are generalized. The influence of nanoparticle size, morphology, surface functionalization, and concentration on friction and wear is analyzed. The lubrication mechanisms of nanolubricants are discussed. The problems and prospects for the development of metal-containing nanomaterials as lubricant additives are considered. The bibliography includes articles published during the last five years.

关键词： coefficient of friction metal-containing nanomaterials nanolubricants nanoparticles wear

CHIRAL RING OF Sp(N) AND SO(N) SUPeRSYMMeTRIC GAUGe THeORY IN FOUR DIMeNSIONS

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Chinese Annals of Mathematics,Series B 2003年第4期24卷 403-414页

作者： e.WITTeN Institute for Advanced Study PrincetonNJ 08540USA

The chiral ring of classical supersymmetric Yang-Mills theory with gauge group Sp(N) or SO(N) is computed, extending previous work (of Cachazo, Douglas, Seiberg, and the author)for SU(N). The result is that, as has been conjectured, the ring is generated by the usualglueball superfield S ～ Tr WαWα, with the relation Sh = 0, h being the dual Coxeter *** this proposition has important implications for the behavior of the quantum theory,the statement and (for the most part) the proofs amount to assertions about Lie groups withno direct reference to gauge theory.

关键词： Chiral ring Gauge group Lie group Supersymmetric gauge theory

Formation of efficient dye-sensitized solar cells by introducing an interfacial layer of hierarchically ordered macro-mesoporous TiO_2 film

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Science China Chemistry 2011年第6期54卷 930-935页

作者： HALPeRT Jonathan e State Key Laboratory of Multi-phase Complex Systems Institute of Process engineering Chinese Academy of Sciences

Hierarchically ordered macro-mesoporous TiO2 films (Ti-Ma-Me) were fabricated on fluorine-doped tin oxide (FTO) substrates through the confinement self-assembly method. The prepared Ti-Ma-Me possesses periodically ordered structure and a large specific surface area, which was applied as an interfacial layer between the nanocrystalline TiO2 film (P25-TiO2) and FTO electrode in the dye-sensitized solar cell (DSSC). The introduction of a Ti-Ma-Me interfacial layer increased the shortcircuit current density (Jsc) from 7.49 to 10.65 mA/cm2 and the open-circuit voltage (Voc) from 0.65 to 0.70 V as the result of its improved light harvesting efficiency by allowing for the high roughness factor and enhanced multiple internal reflection or scattering as well as reducing the back-transport reaction by blocking direct contact between the electrolyte and FTO electrode. Therefore, the photovoltaic conversion efficiency (η) was improved by 83% from 3.04% to 5.55%, as compared to a device using a bare P25 TiO2 photoanode.

关键词： dye-sensitized solar cells hierarchical ordered macro-mesoporous photoanode

Lepton electric Charge Swap at the 10 TeV energy Scale

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Communications in Theoretical Physics 2013年第11期60卷 561-570页

作者： e. Koorambas 8A Chatzikosta 11521 Ampelokipi Athens Greece

We investigate the nature of the dark matter by proposing a mechanism for the breaking of local rotational symmetry between ordinary third family leptons and proposed non-regular leptons at energy scales below 10 TeV. This symmetry breaking mechanism involves electric charge swap between ordinary families of leptons can and produces highly massive non-regular leptons of order 0 （1 TeV） mass unobservable at energy scales below 10 TeV （the scale of LeP Ⅰ, Ⅱ and neutrino oscillation experiments）. electric charge swap between ordinary families of leptons produces heavy neutral non-regular leptons with order 0 （1 TeV） masses, which may form cold dark matter. The existence of these proposed leptons can be tested once the Large Hadron Collider （LHC） becomes operative at 10 TeV energy-scales. This proposition may have far reaching applications in astrophysics and cosmology.

关键词： conservation law in decays group theory Brane and extra dimensions

Southeast Asian Perspectives on Nutrition Needs for the New Millennium

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Biomedical and environmental Sciences 2001年第1期14卷 75-81页

作者： e-SIONG Tee Head Division of Human Nutrition Institute for Medical Research

Over the last three decades, there has been significant changes in the lifestyles of communities, including food habits, and food purchasing and consumption patterns in the Southeast Asian region. As a result, there is a definite change in the food and nutrition issues in the region. Nutritional deficiencies in many of these countries are slowly being decreased in magnitude. On the other hand, the significant proportions of the population are now faced with the other facet of the malnutrition problem, namely diet related chronic diseases. However, because of the different stages of socio economic development, the extent of each of these extremes of the malnutrition problems varies considerably between the different countries in Southeast Asia. Nutrition needs in the new millennium would necessarily differ somewhat among these countries while at the same time, there would be a considerable amount of similarities. This presentation highlights several macro issues that countries in the region may focus on in the near future. Various intervention programmes have been undertaken by authorities to tackle the co existence of twin faces of malnutrition in many developing countries. It would be desirable to have a blue print of such programmes and activities in the National Plans of Action for Nutrition (NPANs). The NPAN should be more than a framework or a descriptive document. It should be a tool for action, an operational plan that sets out priorities; identifies projects and activities, with details of implementation such as what, how and when; designates responsibilities and accountability for the activities; identifies resource requirements and their source; and sets out the plan for monitoring and evaluation. One of the main obstacles in the formulation and effective implementation of intervention programmes in developing countries is the lack of comprehensive data on the extent of the problems in many cases and the causes of such problems specificy to the

关键词： Developing Countries Life Style Nutrition Policy Public Health Asia Southeastern Data Collection Humans International Cooperation Nutrition Disorders Nutrition Surveys Nutritional Status Public Policy

X Y Z particles at BABAR

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Chinese Physics C 2010年第6期34卷 644-649页

作者： e.Prencipe LAPP-Laboratoire de Annecy de Physique de Particules

This paper intends to shortly summarize the recent results on Spectroscopy, published from the BABAR Collaboration. The BABAR experiment is a B-factory, at SLAC, where asymmetric energy beams of electron-positron are accelerated and collide at the energy in the center of mass of T（4S）. In 9 years of data taking, BABAR had collected 433 fb^-1 equivalent luminosity on-peak-data at the T（4S） energy, 30 fb^-1 data at the T（3S） energy, 15 fb^-1 data at the T（2S） energy, and a scan around T（4S） was done, collecting 25 pb^-1 every 5 MeV. Thanks to the high luminosity achieved, it is possible to perform high precision measurements, and spectroscopy studies. An update on the measurement of the state X（3872） will be given, as final result published by using the whole dataset available. Then, a new preliminary Y（4260） measurement is reported, and the study of the invariant mass J/ψπ^＋π^- in ISR events is shown, where no evidence of the state Y（4050） is highlighted. As conclusion, the results on the angular distribution analysis performed on the state Z（4430） are reported.

关键词： spectroscopy charmonium BABAR

How Specific is Non-Hypersensitive Host and Nonhost Resistance of Barley to Rust and Mildew Fungi?

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Journal of Integrative Agriculture 2014年第2期13卷 244-254页

作者： Niks R e Laboratory of Plant Breeding Wageningen UniversityP.O.Box 3866700 AJ WageningenThe Netherlands

Full nonhost resistance can be defined as immunity, displayed by an entire plant species against all genotypes of a plant pathogen. Interesting biological questions are, whether the genes responsible for the nonhost status of a plant species have a general or a specific effectiveness to heterologous （＂nonhost＂） pathogens？ Is the nonhost resistance to pathogens of plant species that are related to the nonhost based on R-genes or on other types of genes？ We study this question in barley （Hordeum vulgare L.）, which is a near-nonhost to several rusts （Puccinia） of cereals and grasses. By crosses and selection we accumulated susceptibility and developed an experimental line, SusPtrit, with high susceptibility to at least nine different heterologous rust taxa such as the wheat and Agropyron leaf rusts （P. triticina and P. persistens, respectively）. At the microscopic level there is also some variation among barley accessions in the degree that the heterologous wheat powdery mildew （Blumeria graminis ***. tritici） is able to form haustoria in epidermal cells. So, also the genetics of the variation in level of nonhost resistance to heterologous mildew fungi can be studied in barley. Our data obtained on mapping populations involving three regular nonhost-immune accessions （Vada, Cebada Capa and Golden Promise） suggest that nonhost resistance is the joined effect of multiple, quantitative genes （QTLs） and very occasionally a major gene （R-gene？） is involved. Most QTLs have effect to only one or two heterologous rusts, but some have a wider spectrum. This was confirmed in a set of QTL-NILs. Those QTL-NILs are used to fine-map the effective genes. In some cases, a QTL region with effectiveness to several heterologous rusts might be a cluster of genes with a more narrow spectrum of effectiveness. Our evidence suggests that nonhost resistance in barley to rust and powdery mildew fungi of related Gramineae is not due to R-genes, but to pathogen species-specific quantitative resi

关键词： genetics specificity basal resistance