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Effects of diurnal temperature range on adult size and emergence times from diapausing pupae in Papilio glaucus and R canadensis （Papilionidae）

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Insect Science 2011年第4期18卷 435-442页

作者： j. Mark Scriber Brittany Sonke Department of Entomology Michigan State University East Lansing Michigan McGuire Center for Lepidoptera and Biodiversity Flonda Museum of Natural History University of Florida Gainesville Florida USA

With recent climate warming trends, both the increase in thermal variance （i.e., diurnal temperature range; DTR） as well as increased mean temperature may impact many different organisms, especially poikilothermic invertebrates. Predictions of insect developmental rates using degree-days （thermal unit accumulations above the developmental base threshold of the insect） are based on daily mean temperatures, regardless of DTR. However, non-linearity and variance in the means and extremes are often ignored. The role of thermal variance （e.g., daily temperature extremes and DTR） was evaluated experimentally for two swallowtail butterfly sister species using a common day/night photoperiod of 18 ： 6 h photo ： scoto-phase and corresponding daytime thermophase and nighttime cryophase periods of 22 ： 22℃ （constant 22℃）, 24 ： 16℃, and 26 ： 10℃（all three treatments had the same daily mean and the same degree-day accumulations）. Although developmental rates ofpost-diapause pupae were largely unaffected for both species, our results show that sizes in P canadensis females （but not males） were smaller in the treatments with more variance （26℃ ： 10℃） compared to constant 22℃. Such potentially significant impacts of size reduction in P canadensis females were not observed in P glaucus males or females under the same series ofthermo-period treatments.

关键词： climate warming degree-days diurnal temperature range (DTR) photoperiods swallowtail butterflies thermoperiods

Methane Emissions from Grazing Holstein-Friesian Heifers at Different Ages Estimated Using the Sulfur Hexafluoride Tracer Technique

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Engineering 2017年第5期3卷 753-759页

作者： Steven j. Morrisonn j.dith McBride Alan W. Gordon Alastair R. G. Wylie Tianhai Yan Agri-Food and Biosciences Institute Hillsborough County Down BT26 6DR UK Agri-Food and Biosciences Institute Belfast BT9 5PX UK

Although the effect of animal and diet factors on enteric methane （CH4） emissions from confined cattle has been extensively examined, less data is available regarding CH4 emissions from grazing young cattle. A study was undertaken to evaluate the effect of the physiological state of Holstein-Friesian heifers on their enteric CH4 emissions while grazing a perennial ryegrass sward. Two experiments were conducted： Experiment 1 ran from May 2011 for 11 weeks and Experiment 2 ran from August 2011 for 10 weeks. In each experiment, Holstein-Friesian heifers were divided into three treatment groups （12 animals/group） consisting of calves, yearling heifers, and in-calf heifers （average ages： 8.5, 14.5, and 20.5 months, respectively）. Methane emissions were estimated for each animal in the final week of each experiment using the sulfur hexafluoride tracer technique. Dry matter （DM） intake was estimated using the calculated metabolizable energy （ME） requirement divided by the ME concentration in the grazed grass. As expected, live weight increased with increasing animal age （P 〈 0.001）; however, there was no difference in live weight gain among the three groups in Experiment 1, although in Experiment 2, this variable decreased with increasing animal age （P 〈 0.001 ）. In Experiment 1, yearling heifers had the highest CH4 emissions （g·d^-1） and in-calf heifers produced more than calves （P 〈 0.001 ）. When expressed as CH4 emissions per unit of live weight, DM intake, and gross energy （GE） intake, yearling heifers had higher emission rates than calves and in-calf heifers （P 〈 0.001）. However, the effects on CH4 emissions were different in Experiment 2, in which CH, emissions （g·d^-1） increased linearly with increasing animal age （P 〈 0.001）, although the difference between yearling and in-calf heifers was not significant. The CH4/live weight ratio was lower in in-calf heifers than in the other two groups （P 〈 0.001 ）, while CH4 energy output as a proportion of GE intake was lower

关键词： Methane emission Grazing dairy heifer Prediction Sulfur hexafluoride tracer technique

Convergence and exact solutions of spline finite strip method using unitary transformation approach

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Applied Mathematics and Mechanics(English Edition) 2011年第11期32卷 1407-1422页

作者： j. KONG D. THUNG Division of Building Science and Technology City University of Hong Kong Hong Kong P. R. China School of Creative Media City University of Hong Kong Hong Kong P. R. China

The spline finite strip method （FSM） is one of the most popular numerical methods for analyzing prismatic structures. Efficacy and convergence of the method have been demonstrated in previous studies by comparing only numerical results with analytical results of some benchmark problems. To date, no exact solutions of the method or its explicit forms of error terms have been derived to show its convergence analytically. As such, in this paper, the mathematical exact solutions of spline finite strips in the plate analysis are derived using a unitary transformation approach （abbreviated as the U-transformation method herein）. These exact solutions are presented for the first time in open literature. Unlike the conventional spline FSM which involves assembly of the global matrix equation and its numerical solution, the U-transformation method decouples the global matrix equation into the one involving only two unknowns, thus rendering the exact solutions of the spline finite strip to be derived explicitly. By taking Taylor＇s series expansion of the exact solution, error terms and convergence rates are also derived explicitly and compared directly with other numerical methods. In this regard, the spline FSM converges at the same rate as a non-conforming finite element, yet involving a smaller number of unknowns compared to the latter. The convergence rate is also found superior to the conventional finite difference method.

关键词： spline finite strip U-transformation plate symmetry

Edge effects on plant diversity in tropical forest ecosystems at Periyar Wildlife sanctuary in the Western Ghats of India

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j.urnal of Forestry Research 2013年第3期24卷 403-418页

作者： Somaiah Sundarapandian Pascal j. Karoor Department of Ecology and Environmental Sciences School of Life Sciences Pondicherry UniversityPuducherry India

Forest resource conservation has been widely accepted as a key to sustain the local and regional economic development. The forest edges are affected by anthropogenic activities including deforestation, forest fragmentation, selective logging, extraction of non-timber forest products, collection of medicinal plants, recreations, hydroelectric pro- j.cts and its associated developmental activities, which alter the biodiver- sity. The present study intends to evaluate the edge effect on vegetation structure and species compositions in the tropical forest ecosystems at Periyar Wildlife Sanctuary in the Western Ghats. High species richness （number of species） and Shannon＇s diversity indices were observed in the site IlI （completely undisturbed forest） compared to site I （adj.cent to the village/edge of the forest, which is next to the teal（ plantation, severely disturbed forest） and site II （in between the undisturbed forest and mod- erately disturbed forest） while density of tree species showed greater value in site II. Single species such as Tectona grandis （IVI of 80） and Terminaliapaniculata （IVI of 112） were the dominant tree species in site I and site II, respectively, whereas, in site III Terminalia bellirica, Bishofia j.vanica and Syzgium gardneri shared the dominance. Perturba- tion leads to alien plant invasion particularly Lantana camara, Eupato- rium odoratum and Ageratum conizoides. Site II is at forest transition level because the site is dominated by both natural species as well as plantation species such as Tectona grandis. This site seems to be a buffer zone on natural forest and plantations. Further studies are required to analyse the real patterns of regeneration and dynamic change due to human impact by long term monitoring with the establishment of perma- nent plots.

关键词： anthropogenic disturbance biodiversity edge effect tropi-cal forest Western Ghats

Geometrically constrained isogeometric parameterizedlevel-set based topology optimization via trimmed elements

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Frontiers of Mechanical Engineering 2016年第4期11卷 328-343页

作者： Yingj.n WANG David j. BENSON School of Mechanical and Automotive Engineering South China University of Technology Guangzhou 510641 China Department ofMechanical Engineering McGill University Montreal H3AOC3 Canada Department of Structural Engineering University of California SanDiego 92093 USA

In this paper, an approach based on the fast point-in-polygon (PIP) algorithm and trimmed elements is proposed for isogeometric topology optimization (TO) with arbitrary geometric constraints. The isogeometric parameterized level-set-based TO method, which directly uses the non-uniform rational basis splines (NURBS) for both level set function (LSF) parameterization and obj.ctive function calculation, provides higher accuracy and efficiency than previous methods. The integration of trimmed elements is completed by the efficient quadrature rule that can design the quadrature points and weights for arbitrary geometric shape. Numerical examples demonstrate the efficiency and flexibility of the method.

关键词： isogeometric analysis topology optimization level set method arbitrary geometric constraint trimmed element

Roles, Functions, and Mechanisms of Long Non-coding RNAs in Cancer

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Genomics, Proteomics & Bioinformatics 2016年第1期14卷 42-54页

作者： Yiwen Fang Melissa j. Fullwood cancer science institute of singapore national university of singapore Singapore 117599 Singapore School of Biological Sciences Nanyang Technological University Singapore 637551 Singapore Institute of Molecular and Cell Biology Agency for Science Technology and Research (A*STAR) Singapore 138673 Singapore Yale-NUS Liberal Arts College Singapore 138527 Singapore

Long non-coding RNAs （ineRNAs） play important roles in cancer. They are involved in chromatin remodeling, as well as transcriptional and post-transcriptional regulation, through a vari- ety of chromatin-based mechanisms and via cross-talk with other RNA species, lncRNAs can func- tion as decoys, scaffolds, and enhancer RNAs. This review summarizes the characteristics of lncRNAs, including their roles, functions, and working mechanisms, describes methods for identi- fying and annotating lncRNAs, and discusses future opportunities for lncRNA-based therapies using antisense oligonucleotides.

关键词： IncRNAS Chromatin Transcription regulation Antisense oligonucleotides Cancer

Electrodynamics of Abrikosov vortices： the field theoretical formulation

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Frontiers of physics 2011年第4期6卷 357-369页

作者： Aron j. Beekman j.n Zaanen Instituut-Lorentz for Theoretical Physics Universiteit Leiden P. O. Box 9506 2300 RA Leiden The Netherlands

Electrodynamic phenomena related to vortices in superconductors have been studied since their prediction by Abrikosov, and seem to hold no fundamental mysteries. However, most of the effects are treated separately, with no guiding principles. We demonstrate that the relativistic vortex worldsheet in spacetime is the obj.ct that naturally conveys all electric and magnetic information, for which we obtain simple and concise equations. Breaking Lorentz invariance leads to down-to-earth Abrikosov vortices, and special limits of these equations include for instance dynamic Meissner screening and the AC j.sephson relation. On a deeper level, we explore the electrodynamics of two-form sources in the absence of electric monopoles, in which the electromagnetic field strength itself acquires the characteristics of a gauge field. This novel framework leaves room for unexpected surprises .

关键词： Abrikosov vortex, electromagnetism, Maxwell equations, differential geometry multivalued fields

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慈悲心肠第1版

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Molecular level simulations on multi-component systems --a morphology prediction method

1983年

作者：（西）加尔多斯（B.P.Galdos）刘煜译

来源：汇雅图书（南通市图书馆... 评论

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Frontiers of Chemical Science and Engineering 2013年第1期7卷 49-54页

作者： C. SCHMIDT j. ULRICH Center for Engineering Science Thermal Process Engineering Martin Luther University Halle-Wittenberg D-06099 Halle (Saale) Germany

The crystal morphology grown from a solution composed of an organic solvent, solute and additive can be predicted reliably by a computational method. Modeling the supersaturated solution as liquid phase is achieved by employing commercial software. The molecular composition of this solution is a required input parameter. The face specific diffusion coefficient of the solid （crystal surface） and liquid （solution） system is determined using the molecular dynamics procedure. The obtained diffusion coefficient is related to the specific face growth rate via the attachment energy of the pure morphology. The significant improvements are achieved in the morphology prediction because the investigation on the face growth rates in a complex growth environment （as multi-component solutions with additives） can be carried out based on the diffusion coefficients.

关键词： crystallization morphology molecular dynamics solution