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Differential effects of short term winter thermal stress on diapausing tiger swallowtail butterflies （Papilio spp.）

Insect Science 2012年第3期19卷 277-285页

作者： j. mark Scriber Emily Maher Matthew L. Aardema Department of Entomology Michigan State University East Lansing MI McGuire Center for Lepidoptera and Biodiversity Florida Museum of Natural History University of Florida Gainesville FL Department of Ecology and Evolutionary Biology Princeton University Princeton N J USA

It is generally thought that insects inhabiting lower latitudes are more severely impacted by changes in their thermal environment than are high latitude species. This is attributed to the wider range of temperatures to which high-latitude species are exposed. By contrast, low-latitude species have typically evolved in more thermally stable environments with a narrower range of temperature variation. However, deviation from this pattern can occur and here we report that under variable winter conditions a higher latitude species may be more sensitive to thermal variation than its lower latitude sister species. Using split broods, we examined the survival and adult emergence success of diapausing pupae of Papilio canadensis and P. glaucus, as well as a unique, recombinant hybrid population （＂late-flight＂） to short periods of mid-winter cold and heat stress. Our results indicate that the higher latitude, univoltine populations （P. canadensis and late-flights） exhibit lower pupal survival than the lower latitude, facultative diapauser （P. glaucus） for all mid-winter thermal stress treatments, both high and low. Size differences alone do not appear to account for the observed differences in survival or metabolic costs in these three pheno- types, as late-flight individuals are similar in size to R glaucus. We attribute the observed differences in survival and weight loss to potential metabolic differences and variation in the intensity of diapause, in addition to divergent adaptation to winter precipitation levels （e.g. snow cover） and the influences this may have on microhabitat temperature moderation.

关键词： climate change developmental threshold incipient hybrid species metabolic cost Papilionidae post-diapause delays thermal stress

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In Vivo and In Vitro Degradation Behavior of Magnesium Alloys as Biomaterials

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j.urnal of Materials Science & Technology 2012年第3期28卷 261-267页

作者： Dingchuan Xue Yeoheung Yun Zongqing Tan Zhongyun Dong mark j. Schulz Department of Chemical and Materials Engineering University of Cincinnati OH 45221 USA Department of Bioengineering North Carolina A ＆ T State University Greensboro NC 27411 USA Department of Internal Medicine University of Cincinnati OH 45221 USA Department of Mechanical Engineering University of Cincinnati OH 45221 USA

The corrosion behavior of pure Mg,AZ31,and AZ91D were evaluated in various in vitro and in vivo environments to investigate the potential application of these metals as biodegradable implant *** polarization tests and immersion tests were performed in different simulated body solutions,such as distilled（DI） water,simulated body fluid（SBF） and phosphate buffered solution（PBS）.Mg/Mg alloys were also implanted in different places in a mouse for in vivo weight loss and biocompatibility *** in vivo subcutis bio-corrosion rate was lower than the corrosion rate for all of the in vitro simulated corrosive *** Mg/Mg alloys were biocompatible based on histology results for the liver,heart,kidney,skin and lung of the mouse during the two months *** microscopy and scanning electron microscopy were carried out to investigate the morphology and topography of Mg/Mg alloys after immersion testing and implantation to understand the corrosion mechanisms.

关键词： Mg/Mg alloys In vitro/in vivo testing Bio-degradation rate Biocompatibility

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美股科技双杰崛起

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商业周刊（中文版） 2024年第5期 48-49页

作者： Eric j.Weiner j.ran Wittenstein mark Gurman 孟洁冰(译) 不详

十多年来,少数几家科技巨头推动美国股市一路向前,带来了超高速增长的希望。你熟知这些家喻户晓的名字:比如谷歌的母公司Alphabet、亚马逊公司(***)、苹果公司、Facebook的母公司Meta、微软公司和特斯拉公司。这些公司的名号组成了各种... 详细信息

十多年来,少数几家科技巨头推动美国股市一路向前,带来了超高速增长的希望。你熟知这些家喻户晓的名字:比如谷歌的母公司Alphabet、亚马逊公司(***)、苹果公司、Facebook的母公司Meta、微软公司和特斯拉公司。这些公司的名号组成了各种首字母缩略词——FANG、FAANG、MAMAA——几乎成为每个投资组合的主要配置。

关键词：投资组合母公司 Amazon 苹果公司亚马逊公司美国股市 .com

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Recent laser upgrades at Sandia's Z-backlighter facility in order to accommodate new requirements for magnetized liner inertial fusion on the Z-machine

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High Power Laser Science and Engineering 2016年第4期4卷 1-12页

作者： j.ns Schwarz Patrick Rambo Darrell armstrong Marius Schollmeier Ian Smith j.nathan Shores Matthias Geissel mark Kimmel j.hn Porter Sandia National Laboratories

The Z-backlighter laser facility primarily consists of two high energy, high-power laser systems. Z-Beamlet laser(ZBL)(Rambo et al., Appl. Opt. 44, 2421(2005)) is a multi-kj.class, nanosecond laser operating at 1054 nm which is frequency doubled to 527 nm in order to provide x-ray backlighting of high energy density events on the Z-machine. Z-Petawatt(ZPW)(Schwarz et al., j. Phys.: Conf. Ser. 112, 032020(2008)) is a petawatt-class system operating at 1054 nm delivering up to 500 j.in 500 fs for backlighting and various short-pulse laser experiments(see also Figure 10 for a facility overview). With the development of the magnetized liner inertial fusion(MagLIF) concept on the Z-machine, the primary backlighting missions of ZBL and ZPW have been adj.sted accordingly. As a result, we have focused our recent efforts on increasing the output energy of ZBL from 2 to 4 kj.at 527 nm by modifying the fiber front end to now include extra bandwidth(for stimulated Brillouin scattering suppression). The MagLIF concept requires a well-defined/behaved beam for interaction with the pressurized fuel. Hence we have made great efforts to implement an adaptive optics system on ZBL and have explored the use of phase plates. We are also exploring concepts to use ZPW as a backlighter for ZBL driven MagLIF experiments. Alternatively, ZPW could be used as an additional fusion fuel pre-heater or as a temporally flexible high energy pre-pulse. All of these concepts require the ability to operate the ZPW in a nanosecond long-pulse mode, in which the beam can co-propagate with ZBL. Some of the proposed modifications are complete and most of them are well on their way.

关键词： adaptive optics high energy lasers MagLIF OPCPA petawatt lasers SBS suppression

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The Salicylic Acid Receptor NPR3 Is a Negative Regulator of the Transcriptional Defense Response during Early Flower Development in Arabidopsis

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Molecular Plant 2013年第3期6卷 802-816页

作者： Zi Shi Siela Maximova Yi Liu j.seph Verica mark j. Guiltinan The Huck Institutes of the Life Sciences Pennsylvania State University University Park PA 16802 USA Department of Plant Science Pennsylvania State University University Park PA 16802 USA

Arabidopsis NON-EXPRESSOR OF PR1 （NPR1） is a transcription co-activator that plays a central role in regulating the transcriptional response to plant pathogens. The NPR family consists of NPR1 and five NPRl-like genes. The NPR1 paralog NPR3 has recently been shown to function as a receptor of the plant hormone salicylic acid and to mediate proteosomal degradation of NPR1. The function of NPR3 protein during early flower development was revealed through a detailed molecular-genetic analysis including promoter transcriptional fusion analysis, phenotype characterization of npr3-3 mutants/overexpressors, and whole-plant fitness analysis. The physical interaction between NPR3 and NPR1/ TGA2 was explored using bimolecular fluorescence complementation analysis in onion epidermal cells, Here, we show that NPR3 expression was strongest in the petals and sepals of developing flowers and declined after flower opening. Consistently with this observation, an npr3 knockout mutant displayed enhanced resistance to Pseudomonas syringae infection of immature flowers, but not leaves. Developing npr3 flowers exhibited increased levels of basal and induced PR1 transcript accumulation. However, the npr3 mutant showed lower fitness compared to Col-0 in the absence of pathogen. Moreover, NPR3 was shown to interact with NPR1 and TGA2 in vivo. Our data suggest that NPR3 is a negative regulator of defense responses during early flower development and it may function through the association with both NPR1 and TGA2.

关键词： plant defense NPR3 negative regulator Arabidopsis flower.

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Endogenous Glucocorticoids and Bone

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Bone Research 2013年第2期1卷 107-119页

作者： Hong Zhou mark S. Cooper markus j. Seibel Bone Research Program ANZAC Research Institute Concord Clinical School The University of Sydney Department of Endocrinology & Metabolism Concord Hospital

While the adverse effects of glucocorticoids on bone are well described, positive effects of glucocorticoids on the differentiation of osteoblasts are also observed. These paradoxical effects of glucocorticoids are dose dependent. At both physiologicaland supraphysiological levels of glucocorticoids, osteoblasts and osteocytes are the maj.r glucocorticoid target cells. However, the response of the osteoblasts to each of these is quite distinct. At physiology levels, glucocorticoids direct mesenchymal progenitor cells to differentiate towards osteoblasts and thus increase bone formation in a positive way. In contrast with ageing, the excess production of glucocorticoids, at both systemic and intracellular levels, appear to impact on osteoblast and osteocytes in a negative way in a similar fashion to that seen with therapeutic glucocorticoids. This review will focus on therole of glucocorticoids in normal bone physiology, with particular emphasis on the mechanism by which endogenous glucocorticoids impact on bone and its constituent cells.

关键词： glucocorticoids mechanisms of action bone osteoblasts skeletal development Wnt signaling

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Assessing ecological and physiological costs of melanism in North American Papilio glaucus females: two decades of dark morph frequency declines

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Insect Science 2020年第3期27卷 583-612页

作者： j.mark Scriber Department of Entomology Michigan State UniversityEast LansingMichiganUSA McGuire Center for Lepidoptera and Biodiversity Florida Museum of Natural HistoryUniversity of FloridaGainesvilleFloridaUSA

Polymorphisms for melanic form of insects may provide various selective ***,melanic alleles may have significant/subtle pleiotrophic“costs.”Several potential pleiotrophic effects of the W(=Y)‐linked melanism gene in Papilio glaucus L.(Lepidoptera)showed no costs for melanic versus yellow in adult size,oviposition preferences,fecundity,egg viability,larval survival/growth rates,cold stress tolerance,or postdiapause emergence *** selection(males choosing yellow rather than mimetic dark females)had been suggested to provide a balanced polymorphism in ***,but spermatophore counts in wild females and direct field tethering studies of size‐matched pairs of virgin females(dark and yellow),show that male preferences are random or frequency‐dependent from Florida to Michigan,providing no yellow counter‐*** frequency declines of dark(melanic/mimetic)females in *** populations are shown in several maj.r populations from Florida(27.3°N latitude)to Ohio(38.5°N).Summer temperatures have increased significantly at all these locations during this time(1999–2018),but whether dark morphs may be more vulnerable(in any stage)to such climate warming remains to be *** potential reasons for the frequency declines in mimetic females are discussed:(i)genetic introgression of Z‐linked melanism suppressor genes from ***(R&j.and the hybrid species,***(Pavulaan&Wright),(ii)differential developmental incompatibilities,or Haldane effects,known to occur in hybrids,(iii)selection against intermediately melanic(“dusty”)females(with the W‐linked melanic gene,b+)which higher temperatures can cause.

关键词： climate warming ecology of melanism incomplete mimicry pleiotrophic costs

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Fundamentals of operations management / mark M. Davis, Nicholas j. Aquilano, Richard B. Chase. 4th ed.

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丛书名： McGraw-Hill/Irwin series operations and decision sciences

2003年

作者： mark M. Davis Nicholas j. Aquilano Richard B. Chase.

First ed. published under: Aquilano, Nicholas j.

ISBN: (数字)0072402857

ISBN: (纸本)007119469X

First ed. published under: Aquilano, Nicholas j.

关键词： Production management.

来源：畅想之星图书光盘版（南... 评论

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Evidence for the Role Evolutionary Increase Yield in Cotton of Transfer Cells in the in Seed and Fiber Biomass

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Molecular Plant 2010年第6期3卷 1075-1086页

作者： Deborah A. Pugh Christina E. Offler mark j. Talbot Yong-Ling Ruan School of Environmental and Life Sciences University of Newcastle Callaghan NSW 2308 Australia Australia-China Research Centre for Crop Improvement University of Newcastle Callaghan NSW 2308 Australia CSIRO Plant Industry Canberra ACT 2601 Australia

Transfer cells （TCs） are specialized cells exhibiting invaginated wall ingrowths （Wls）, thereby amplifying their plasma membrane surface area （PMSA） and hence the capacity to transport nutrients. However, it remains unknown as to whether TCs play a role in biomass yield increase during evolution or domestication. Here, we examine this issue from a comparative evolutionary perspective. The cultivated tetraploid AD genome species of cotton and its A and D genome diploid progenitors displayed high, medium, and low seed and fiber biomass yield, respectively. In all three species, cells of the innermost layer of the seed coat j.xtaposed to the filial tissues trans-differentiated to a TC morphology. Electron microscopic analyses revealed that these TCs are characterized by sequential formation of flange and reticulate Wls during the phase of rapid increase in seed biomass. Significantly, TCs from the tetraploid species developed substantially more flange and reticulate Wls and exhibited a higher degree of reticulate WI formation than their progenitors. Consequently, the estimated PMSA of TCs of the tetraploid species was about 4 and 70 times higher than that of TCs of the A and D genome progenitors, respectively, which correlates positively with seed and fiber biomass yield. Further, TCs with extensive Wls in the tetraploid species had much stronger expression of sucrose synthase, a key enzyme involved in TC Wl formation and function, than those from the A and D progenitors. The analyses provide a set of novel evidence that the development of TC Wls may play an important role in the increase of seed and fiber biomass yield through polyploidization during evolution.

关键词： Callose cell wall cellulose cotton fiber evolution polyploidization seed development sucrose synthase transfer cell.

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Efficient ray casting of volumetric images using distance maps for empty space skipping

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Computational Visual Media 2020年第1期6卷 53-63页

作者： Lachlan j.Deakin mark A.Knackstedt Australian National University Canberra2601Australia

Volume and isosurface rendering are methods of proj.cting volumetric images to two dimensions for *** methods are common in medical imaging and scientific ***-mounted optical see-through displays have recently become an affordable technology and are a promising platform for volumetric image *** displayed on a head-mounted display must be presented at a high frame rate and with low latency to compensate for head *** latency can be j.rring and may cause cybersickness which has similar symptoms to motion *** images can be very computationally expensive to render as they often have hundreds of millions of scalar ***,certain materials in images such as air surrounding an obj.ct boundary are often made transparent and need not be sampled,which improves rendering *** our previous work we introduced a novel ray traversal technique for rendering large sparse volumetric images at high frame *** method relied on the computation of an occupancy and distance map to speed up ray traversal through empty *** this work we achieve higher frame rates than our previous work with an improved method of resuming empty space skipping and the use of anisotropic Chebyshev distance *** optimised algorithm for computing Chebyshev distance maps on a graphical processing unit is introduced supporting real-time transfer function editing.

关键词： ray casting volume rendering isosurface rendering distance maps

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