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Placental accommodations for transport and metabolism during intra-uterine crowding in pigs

Journal of Animal science and Biotechnology 2015年第2期6卷 163-176页

作者： Jeffrey L Vallet Anthony K Mc Neel Jeremy R Miles Bradley A Freking u.s. department of agriculture Agricultural Research Service U.S. Meat Animal Research CenterState Spur 18D Clay Center NE 68933 USA

Litter size and birth weights are limited by uterine capacity, defined as the ability of the uterus to maintain the appropriate development of some number of conceptuses. uterine capacity is the result of the combined effects of uterine, placental and embryo/fetal function. The number of living conceptuses that the uterus is capable of supporting is greater during early gestation compared to later gestation. Plots of log fetal weight versus log placental weight also indicate that fetal weights are less sensitive to reduced placental weight （and therefore reduced intrauterine space） in early gestation compared to late gestation. However, even in late gestation, mechanisms still exist that maintain fetal growth when the size of the placenta is reduced. One such mechanism is likely to be improved development of the folded placental-epithelial/maternal-epithelial bilayer. Fold depth, and therefore the maternal fetal interactive surface, increases as gestation advances and is greater in placenta from smal fetuses. On the fetal side of the placenta, the epithelial bilayer is embedded in stromal tissue. Glycosaminoglycans are major components of stroma, including hyaluronan and heparan sulfate. Hyaluronidases and heparanases are present within placental tissu.s. and likely play roles in modification of stromal components to facilitate fold development. Glycosaminoglycans are polymers of forms of glucose （glucosamine, glucuronic acid, iduronic acid） suggesting that glycosaminoglycan synthesis may compete with the glucose needs of the developing fetus. Pig conceptuses are fructogenic, such that a su.s.antial portion of glucose transferred from mother to fetus is converted to fructose. Fructose is an intermediate product in the synthesis of glucosamine from glucose, and glucosamine is linked to regulation of trophoblast cell proliferation through regulation of mTOR. These findings suggest a link between glucose, fructose, glucosamine synthesis, GAG production, and placental m

关键词： Glycosaminoglycans Nutrient transport Placenta

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Analysis of hourly generation patterns at large coal-fired units and implications of transitioning from baseload to load-following electricity supplier

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Journal of Modern Power systems and Clean Energy 2019年第3期7卷 468-474页

作者： Robert Kennedy sMITH u.s. department of Energy Office of Fossil Energy

several factors have led to the decline of electricity generation from coal over the past decade, and projections forecast high rates of growth for wind and solar technologies in coming years. This analysis uses hourly generation data from large coal-fired power stations to determine how operations have been modified in recent years and describes the implications of these changes for plant equipment and unit reliability. The data shows increasing variability in intraday generation output that affects nearly all of the units in the sample, but the magnitude of increase varies widely among plants. Outage patterns were examined as was the relationship between renewable energy growth in a region and the changes in coal plant operations. Aggregate direct and indirect costs associated with running coal plants as load-following units have not yet been quantified in large-scale studies on a sector-wide basis, largely due to differences in how specific equipment responds to output fluctuations. Due to findings from the hourly generation data analysis and the high degree of potential impact on coal plant equipment, the study suggests the development of a new modeling tool that will represent the costs of running coal-fired power plants at lower capacity factors.

关键词： Coal generation Emission intensity Baseload power Capacity factor

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Age at reproductive maturity and effect of age and time of day on sex attraction in the potato psyllid Bactericera cockerelli

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Insect science 2012年第5期19卷 585-594页

作者： Christelle Guedot David R. Horton Peter J. Landolt u.s. department of agriculture Agricultural Research Service 5230 Konnowac Pass Road Wapato WA 98951 USA

The potato psyllid, Baetericera （= Paratrioza） cockerelli （gulc）（Hemiptera： Triozidae）, is a major pest of potato. studies were conducted to determine the age at which both males and females reach reproductive maturity and the effect of age and time of day on sex attraction. Adult B. cockerelli reach reproductive maturity within 48 h post-eclosion, with females being mature on the day of eclosion and males at 1 day post-eclosion. Oviposition generally began 2 days after mating but was delayed when females mated within 2 days post-eclosion. In laboratory olfactometer assays, the age of females used as odor sources and the age of males assayed to these odors did not affect sex attraction, with both younger （1-4-day-old） and older （8-10-day-old） males being attracted to females, regardless of female age （1-4-day-old or 8-10-day-old）. Males assayed to live females at different times during the photophase （between 8：00 and 20：00 hou.s. were attracted to females between 11：00 and 17：00 hou.s. showing a temporal periodicity in sex attraction with B. cockerelli at least during the photophase.

关键词： mate attraction olfactometer oviposition periodicity potato preference,Triozidae

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Anion structural effects on interaction of rare earth element ions with Dowex 50W X8 cation exchange resin

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Journal of Rare Earths 2018年第8期36卷 879-890页

作者： Duane D.Miller Ranjani siriwardane Dustin Mcintyre u.s. department of Energy National Energy Technology Laboratory AECOM

The effect of the anion in the original rare earth element（REE） solution on the reversible ion exchange of Ce nitrate and Ce sulfate with the Dowex 50 W X8 was investigated using attenuated total reflection infrared（ATR-IR） spectroscopy, continuous flow reactor studies coupled with inductively coupled plasma mass spectroscopy（ICP-Ms）, and density functional theory（DFT）. The simulated IR spectrum at the DFT B3 LYP/6-31 G（d） level was compared to the experimental results to characterize the IR spectrum, molecular interactions, and bonding of the ion exchanged species. The continuous liquid flow reactor studies show a capacity of 0.72 mmol/g sorbent for the Ce nitrateand 0.96 mmol/g sorbent for the Ce sulfate with the Dowex 50 W X8. The flow reactor studies reveal the type of solute anion（sO_4^（（2-）） or NO_3^（（-））） associated with the REE during cation exchange significantly affects the sorption capacity of the Dowex 50 W X8 ion exchange resin. The calculated REE binding energy（BE） and the DFT optimized structures suggest that the differences in sorption capacity is the result of the formation of different types of partially ionexchanged Ce_2^（（3＋））2 sO_4^（（2-）） and Ce^（（3＋）） 3 NO_3^（（-））. These results suggest that the solute anion affects the equilibrium constants of the Dowex resin by the formation of a charged layer capable of retaining the counterion. Modifying the sulfonic acid site（H＋） in the Dowex 50 W X8 with the NH_4~＋ counterion does not affect the sorption capacity and retention times of the Ce nitrate and Ce sulfate species. These results suggest that the counterions and co-ions having a finite size, may limit access to the Dowex sulfonate active site where the type of REE cation as a nitrate or sulfate in solution may significantly modify the sorption capacity of the ion exchange resin. similar results are obtained during sorption with nitrates and sulfates of sm and Yb.

关键词： Ion exchange Dowex Anion effects Rare earth metal sorption

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Evolving carbon dioxide emission rate intensities of coal-fired power plant on u.s. electricity operating systems

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Journal of Modern Power systems and Clean Energy 2018年第6期6卷 1103-1112页

作者： Robert Kennedy sMITH u.s. department of Energy Office of Fossil Energy

For many years, coal-fired power plant generation comprised the largest share of electricity in the *** sector. While natural gas plants now constitute a greater portion of the total, coal is projected to remain a shrinking but significant component of u.s. electricity production. Natural gas-fired technologies are dispatchable and versatile generation sources, but the recent and anticipated growth of wind and solar technologies will add nondispatchable, intermittent power generation sources to *** grids. Numerous emissions-related benefits arise from the deployment of these technologies, but they must coexist with coal plants, many of which run most efficiently under baseload operating procedures. Historical monthly emissions data has been analyzed on a sample of coal plants to show how modified coal operations have affected plant emission rates, as measured by carbon dioxide emitted per unit of electricity output. statistically significant correlations between plant capacity factors and emission rate intensity have been observed by the majority of the sample, showing a worsening under more sporadic operations. since nearly all of the coal plants in the sample are generating less electricity, determining the emission impact of operational decisions will assist policymakers as they seek to minimize total system emissions without severe disruptions to electricity cost and service reliability.

关键词： Coal Emission intensity Renewable generation Baseload power generation

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Disruption of Cortical Microtubules by Overexpression of Green Fluorescent Protein-Tagged a-Tubulin 6 Causes a Marked Reduction in Cell Wall synthesis

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Journal of Integrative Plant Biology 2006年第1期48卷 85-98页

作者： David H. Burk Ruiqin Zhong W. Herbert Morrison III Zheng-Hua Ye department of Plant Biology University of Georgia Athens Georgia 30602 USA Richard B. Ru.s.ll agriculture Research Center U.S. Department of Agriculture Agricultural Research Service Athens Georgia 30604 USA

It has been known that the transverse orientation of cortical microtubules （MTs） along the elongation axis is essential for normal cell morphogenesis, but whether cortical MTs are essential for normal cell wall synthesis is still not clear. In the present study, we have investigated whether cortical MTs affect cell wall synthesis by direct alteration of the cortical MT organization in Arabidopsis thaliana. Disruption of the cortical MT organization by expression of an excess amount of green fluorescent protein-tagged a-tubulin 6 （GFP-TuA6） in transgenic Arabidopsis plants was found to cause a marked reduction in cell wall thickness and a de- crease in the cell wall sugars glucose and xylose. Concomitantly, the stem strength of the GFP-TuA6 overexpressors was markedly reduced compared with the wild type. In addition, expression of excess GFP- TuA6 results in an alteration in cell morphogenesis and a severe effect on plant growth and development. Together, these results suggest that the proper organization of cortical MTs is essential for the normal synthesis of plant cell walls.

关键词： Arabidopsis thaliana cell elongation cell wall synthesis cortical microtubules microtubule organization.

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Characterization and application of monoclonal antibodies against shewanella marisflavi, a novel pathogen of Apostichopus japonicus

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Chinese Journal of Oceanology and Limnology 2011年第5期29卷 973-980页

作者：李强景宏丽李华王轶南徐德海 Key Laboratory of Mariculture Agriculture Ministry of China Dalian Ocean University u.s. department of agriculture Agricultural Research Service Aquatic Animal Health Research Laboratory Auburn AL 36832 USA

shewanella marisflavi strain AP629 was certified as a novel pathogen of the sea cucumber Apostichopusjaponicus. In this study, four monoclonal antibodies （MAbs）（3C1, 3D9, 2F2, 2A8） against strain AP629 were developed by immunizing Balb/C mice. 3C1 and 3D9 recognized s. marisflavi only, showing no cross reactivity to other gram-negative bacteria, However, 2F2 and 2A8 showed cross reactivity to all tested bacteria. Indirect immunofluorescence, and immunogold electron microscopy, showed the binding antigens of 3C1 and 3D9 were located at the secretion on the surface of strain AP629. The binding antigens of 2F2 and 2A8 were noted on the membrane of the cells. MAbs 3C1 and 3D9 recognized the lipopolysaccharide fraction of strain AP629, and 2F2 and 2A8 recognized in western-blotting protein antigens with molecular weights of 113 and 128 kDa respectively. MAbs 3C1 and 3D9 have the potential for use in pathogen diagnosis, epidemiology and studies on the mechanism of how s. marisflavi infects A. japonicus. Imrnunohistochemistry with 3C1 or 3D9 identified strain AP629 in the body wall of infected A. japonicus. In the adult sea cucumbers that were infected via body wall injection, positive signals were observed at the site of skin ulceration, and at the connective tissue of the non-ulcerated body wall. In addition, some large blue-stained cells aggregated at the connective tissue colonized by large numbers of bacteria. In juveniles infected via immersion infection, positive signals were observed at the cuticle of the body wall only. Our results suggest that 3C1 and 3D9 could be used in various immunological assays to study the invasion mechanism of strain AP629 in A. japonicus, the law of bacterial colonization, proliferation in different tissu.s.of A. japonicus, and correlation between secretion on the surface of strain AP629 and its pathogenesis to A. japonicus.

关键词： Apostichopusjaponicus shewanella marisflavi monoclonal antibodies

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Early Identification of stable Transformation Events by Combined use of Antibiotic selection and Vital Detection of Green Fluorescent Protein (GFP) in Carrot (Daucus carota L.) Callus

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Agricultural sciences in China 2008年第6期7卷 664-671页

作者： Yuan-Yeu Yau.s.th J Davis Ahmet Ipek Philipp W simon u.s. department of agriculture Agricultural Research Service Department of Horticulture University of Wisconsin-Madison Laboratory of Genetics University of Wisconsin-Madison Madison WI 53706 USA u.s. department of agriculture Agricultural Research Service Department of Horticulture University of Wisconsin-Madison Madison WI 53706 USA

Genetic transformation is a useful technique to complement conventional breeding in crop improvement. Although carrot has been a model organism for in vitro embryogenesis study, genetic transformation of carrot is still lengthy and labor intensive. An efficient transformation and detection system is desirable. Direct infection of Agrobacterium to carrot calli has provided an easy way for carrot genetic transformation. To improve the efficiency of antibiotic selection in this method, we report the combined use of an improved green-fluorescent protein, referred to as smGFP, to establish a versatile selection method for carrot callus transformation system. By combining antibiotic selection with the bright fluorescence observed in the callus tissue, we were able to easily identify stable transformants in early stage of the transformation process. In addition to the GFP expression of the callus cells, the transgenic nature of callus cells was confirmed with southern and Western analysis. We found we can link the simplicity of carrot-callus-cell transformation, early detection of stable transformants with antibiotic selection, visualization of GFP fluorescence, and molecular analysis （southern and Western） of callus tissue （non-photosynthetic tissue） to provide a more efficient way in identifying stable transformants at early stage of carrot transformation.

关键词： Agrobacterium tumefaciens antibiotic selection Daucus carota genetic transformation reporter gene,stable transformed transgene

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Phytochrome-regulated Gene Expression

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Journal of Integrative Plant Biology 2007年第1期49卷 11-20页

作者： Peter H. Quail department of Plant and Microbial Biology University of Cafifomia Berkeley CA 94720 USA u.s. department of agriculture/agriculture Research service-Plant Gene Expression Center 800 Buchanan Street Albany CA 94710 LISA

Identification of all genes involved in the phytochrome （phy）-medieted responses of plants to their light environment is an important goal in providing an overall understanding of light-regulated growth end development. This article highlights end integrates the central findings of two recent comprehensive studies in Arabidopsis that have identified the genome-wide set of phy-reguleted genes that respond rapidly to red-light signals upon first exposure of dark-grown seedlings, and have tested the functional relevance to normal seedling photomorphogenesis of an Initial su.s.t of these genes. The data：（a） reveal considerable complexity in the channeling of the light signals through the different phy-femily members （phyA to phyE） to responsive genes; （b） identify a diversity of transcription-factor-encoding genes as major early, if not primary, targets of phy signaling, end, therefore, as potentially important regulators in the transcriptional-network hierarchy; and （c） identify auxin-related genes as the dominant class among rapidly-regulated, hormone-related genes. However, reverse-genetic functional profiling of a selected su.s.t of these genes reveals that only a limited fraction are necessary for optimal phy-induced seedling deetioletion.

关键词： expression profiling phytochrome signaling transcriptional networks microarrays reverse genetics functional profiling transcription factors auxin-related genes

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synergy between Customer segmentation and Personalization

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Journal of systems science and systems Engineering 2021年第3期30卷 276-287页

作者： Jingtong Zhao department of Industrial Engineering Operations Research Columbia UniversityNew YorkNY10027U.S.

Personalized pricing is on the rise in the retail industry,and it’s been used in many service *** pricing assumes that the platform has an idea of who the customer is,and allows the platform to incentivize the customers based on their characteristics and *** this work,we consider a personalized pricing problem with revisiting *** assume a customer’s utility depends on some feature information and some unobserved personal *** the case where customer utilities are unknown,we propose a heuristic that combines the idea of binary search and feature-based pricing,and show that it outperforms common *** also demonstrate that if we have some information about either the customer utility or the dependence on the feature information,then we can learn the other much faster,and this is what we mean by the synergy between customer segmentation and *** observation can help managers make better personalized decisions for customers that repeatedly interact with the platform.

关键词： Pricing algorithms heuristics personalization

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