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Diapause induction and termination in a commonly univoltine leaf beetle （ Phratora vulgatissima）

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Insect Science 2011年第4期18卷 443-450页

作者： peter Dalin Department of Ecology Swedish University of Agricultural Sciences Uppsela Sweden

TheleafbeetlePhratoravulgatissima（Linnaeus 1758）iscommonlyunivoltine in south-central Sweden but may sometimes initiate a partial second generation. The current study was set out to investigate under what abiotic conditions the beetles initiate a second generation. Using climate chamber experiments, the beetles were shown to have a facultative reproductive diapause induced by declining day-length. The critical day-length （CDL） for diapause induction was estimated to be 18 h and 10 min. In the field, firstgeneration beetles developing to adulthood before August in 2009 became reproductively active and produced a second generation, but most individuals emerged later and were in reproductive diapause. P vulgatissima overwinter as adults and diapause was shown to be maintained until mid-winter in 2008/2009. The cumulative temperature requirement for oviposition after diapause termination was estimated to be 222 day-degrees with a 5.5℃ temperature threshold. Three different day-degree models that were developed to predict the phenology of female oviposition in the spring were validated by comparing model results with field data on the timing of oviposition in previous years. The study suggests that P vulgatissima may initiate a second generation in Sweden if development of the first generation is completed before August. Warmer spring and summer temperatures due to ongoing climate change may cause advanced insect phenology and faster completion of insect life-cycles at northern latitudes, which will affect the proportion of insects that initiate a second generation.

关键词： climate change diapause insect pests population dynamics seasonal adaptations voltinism

The potential of rapid visco-analysis starch pasting profiles to gauge the quality of sorghum as a feed grain for chicken-meat production

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Animal Nutrition 2017年第1期3卷 11-18页

作者： ha h.Truong Ali Khoddami Amy F.Moss Sonia Y.Liu peter h.Selle Poultry Research Foundation Faculty of Veterinary Science The University of Sydney Australian Poultry CRC University of New England Department of Plant and Food Sciences Faculty of Agriculture and Environment The University of Sydney

Thirteen extensively characterised grain sorghum varieties were evaluated in a series of 7 broiler bioassays. The efficiency of energy utilisation of broiler chickens offered sorghum-based diets is problematic and the bulk of dietary energy is derived from sorghum starch. For this reason, rapid visco-analysis(RVA)starch pasting profiles were determined as they may have the potential to assess the quality of sorghum as a feed grain for chicken-meat production. In review, it was found that concentrations of kafirin and total phenolic compounds were negatively correlated with peak and holding RVA viscosities to significant extents across 13 sorghums. In a meta-analysis of 5 broiler bioassays it was found that peak, holding,breakdown and final RVA viscosities were positively correlated with ME:GE ratios and peak and breakdown RVA viscosities with apparent metabolizable energy corrected for nitrogen(AMEn) to significant extents. In a sixth study involving 10 sorghum-based diets peak, holding and breakdown RVA viscosities were positively correlated with ME:GE ratios and AMEn. Therefore, it emerged that RVA starch pasting profiles do hold promise as a relatively rapid means to assess sorghum quality as a feed grain for chicken-meat production. This potential appears to be linked to quantities of kafirin and total phenolic compounds present in sorghum and it would seem that both factors depress RVA starch viscosities in vitro and, in turn, also depress energy utilisation in birds offered sorghum-based diets. Given that other feed grains do not contain kafirin and possess considerably lower concentrations of phenolic compounds, their RVA starch pasting profiles may not be equally indicative.

关键词： Kafirin Phenolics Poultry Rapid visco-analysis Sorghum Starch

Isolation of Microcystins from the Cyanobacterium Planktothrix rubescens Strain No80

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Natural Products and Bioprospecting 2014年第1期4卷 37-45页

作者： Timo h.J.Niedermeyer peter Schmieder Rainer Kurmayer Cyano Biotech Gmbh Magnusstr.1112489 BerlinGermany Interfaculty Institute for Microbiology and Infection Medicine Tubingen Eberhard Karls University TubingenAuf der Morgenstelle 2872076 TubingenGermany Leibniz Institut fur Molekulare Pharmakologie Robert-Rossle-Str.1013125 BerlinGermany Research Institute for Limnology University of InnsbruckMondseestrasse 95310 MondseeAustria

Three minor microcystins have been isolated from a Planktothrix rubescens *** structures have been elucidated by one-and two-dimensional NMR spectroscopy and high-resolution tandem mass spectrometry as the compounds[Asp^(3),(E)-Dhb^(7)]MC-LY(1),[Asp^(3),(E)-Dhb^(7)]MC-htyW(2),and[Asp^(3),(E)-Dhb^(7)]MC-LW(3).The amino acids found at the variable positions 2 and 4 of the microcystin core structure are in accordance with the predicted amino acid substrate activation selectivities of the non-ribosomal peptide synthetases McyA and McyB described earlier for this *** structural microcystin variants produced by this strain were shown to inhibit protein phosphatase 1 in the nanomolar range.

关键词： Planktothrix Cyanobacteria Microcystins Protein phosphatase inhibition

Non-Achievability of Metal-Insulator Transition in Two-Dimensional Systems

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Chinese Physics Letters 2006年第4期23卷 946-949页

作者： A. John peter Zhejiang Institute of Modern Physics Zhejiang University Hangzhou 310027

We present a simple demonstration of the nonfeasibility of metal-insulator transition in an exactly two-dimensional （2D） system. The hartree-Fock potential in the 3D system is suitably modified and presented for the 2D case. The many body effects are included in the screening function, and binding energies of a donor are obtained as a function of impurity concentration so as to find out the possible way leading metal-insulator transition in the 2D system. While solving for the binding energy for a shallow donor in an isolated well of a GaAs/Ga1-x Als As superlattice system within the effective mass approximation, it leads to unphysical results for higher concentrations. It shows that the phase transition, the bound electron entering into the conduction band whereby （h）min=0, is not possible beyond this concentration. The results suggest thai a phase transition is impossible in 213 systems, supporting the scaling theory of localization. The results are compared with the existing data available and discussed in the light of existing literature.

关键词： MOTT TRANSITION QUANTUM-WELLS ELECTRON-GAS 2 DIMENSIONS LOCALIZATION

Limits on light emission from silicon

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Chinese Optics Letters 2009年第4期7卷 268-270页

作者： peter Würfel Institut für Angewandte Physik Universitt KarlsruheD-76128 KarlsruheGermany

Although silicon is an indirect semiconductor, light emission from silicon is governed by the same gener- alized Planck＇s radiation law as the emission from direct semiconductors. The emission intensity is given by the absorptance of the volume in which there is a difference of the quasi Fermi energies. A difference of the Fermi energies may result h＇om the absorption of external light （photoluminescence） or from the injection of electrons and holes via selective contacts （electroluminescence）. The quantum efficiency may be larger than 0.5 for carrier densities below 10^15 cm^-3. At larger densities, non-radiative recombination, in particular Auger recombination dominates. At all carrier densities, the relation between emission intensity and difference of the quasi Fermi energies is maintained. Since this difference is equal to the voltage of a properly designed solar cell, luminescence is the key indicator of material quality for solar cells.

关键词： Carrier concentration Fermi level Light Light emission Photoluminescence Semiconducting silicon Silicon

Trade-offs between prosperity and urban land per capita in major world cities

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Geography and Sustainability 2021年第2期2卷 134-138页

作者： Vita Bakker peter h.Verburg Jasper van Vliet Institute for Environmental Studies Vrije Universiteit AmsterdamDe Boelelaan 10851081HVAmsterdamThe Netherlands

Globally,urban land expands at a faster rate than the corresponding urban population,which comes at a cost of agricultural and natural *** has been identified as an underlying driver of this trend,but it is unclear whether more prosperous cities inevitably have a greater urban land ***,we map urban pros-perity indicators to their relevant Sustainable Development Goals(SDGs)for 64 major world cities and relate these to the corresponding urban land consumption(defined here as built-up land per capita).Results indicate a moderately-weak but significant correlation between overall prosperity and urban land consumption(Spear-man’s correlation,𝜌ρ=0.47,ph for example cities with relatively low prosperity and low urban land consumption in Africa,and cities with high prosperity and low-to-medium urban land consumption in *** moderately-weak correlation in combination with these regional differences suggests that the observed trade-offis avertable and that other drivers moderate this ***,cities can increase their prosperity without additional environmental consequences entailing land take and the conversion of natural and agricultural land.

关键词： Urban land consumption Population density Urban development Sustainable Development Goals(SDGs) Trade-offs

ChARACTERIZATION AND QUANTITATION OF VASOPRESSIN METABOLITES IN RAT BRAIN BY SPECIFIC RADIOIMMUNOASSAY AND hIGh-PRESSURE LIQUID ChROMATOGRAPhY

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Science China Chemistry 1986年第8期29卷 832-843页

作者：王新昌,J.peter h.BURBACh,JEROEN TENhAAF,DAVID DE WIED Department of Biology Nanjing University Rudolf Magnus Institute for Pharmacology Medical Faculty University of Utrecht The netherlands. Rudolf Magnus Institute for Pharmacology Medical Faculty University of Utrecht The netherlands. Rudolf Magnus Institute for Pharmacology Medical Faculty University of Utrecht The netherlands.

The content of endogenons vasopressin (AVP1-9) and its metabolites in rat's various brain areas and pituitary gland was investigated by the combination techniques of high pressure liquid chromatography （hPLC） and radioimmunoassay （RIA）. In addition to the AVP1-9, several compounds with C-terminal AVP immunoreactivity were detected in hypothalamus, hippceampus, amygdala, medulla oblongata and septum. The C-terminal AVP1-9metabolites were virtually absent in the pituitary gland. In view of the highly potent and selective effects oa memory processes of AVP metabolites, some endogenous AVP metabolites in the brain may play an important role in the central nervous system （CNS） function.

关键词： Cyt AV ChARACTERIZATION AND QUANTITATION OF VASOPRESSIN METABOLITES IN RAT BRAIN BY SPECIFIC RADIOIMMUNOASSAY AND hIGh-PRESSURE LIQUID ChROMATOGRAPhY RAT

Predicting short-term thromboembolic risk following Roux-en-Y gastric bypass using supervised machine learning

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1097-1108页

作者： hassam Ali Faisal Inayat Vishali Moond Ahtshamullah Chaudhry Arslan Afzal Zauraiz Anjum hamza Tahir Muhammad Sajeel Anwar Dushyant Singh Dahiya Muhammad Sohaib Afzal Gul Nawaz Amir h Sohail Muhammad Aziz Department of Gastroenterology East Carolina University Brody School of MedicineGreenvilleNC 27834United States Department of Internal Medicine Allama Iqbal Medical CollegeLahorePunjab 54550Pakistan Department of Internal Medicine Saint Peter's University Hospital and Robert Wood Johnson Medical SchoolNew BrunswickNJ 08901United States Department of Internal Medicine St.Dominic's HospitalJacksonMS 39216United States Department of Internal Medicine Rochester General HospitalRochesterNY 14621United States Department of Internal Medicine Jefferson Einstein HospitalPhiladelphiaPA 19141United States Department of Internal Medicine UHS Wilson Medical CenterJohnsonNY 13790United States Division of Gastroenterology Hepatology and MotilityThe University of Kansas School of MedicineKansasKS 66160United States Department of Internal Medicine Louisiana State University HealthShreveportLA 71103United States Department of Surgery University of New Mexico School of MedicineAlbuquerqueNM 87106United States Department of Gastroenterology and hepatology The University of ToledoToledoOH 43606United States

BACKGROUND Roux-en-Y gastric bypass(RYGB)is a widely recognized bariatric procedure that is particularly beneficial for patients with class III *** aids in significant weight loss and improves obesity-related medical *** its effectiveness,postoperative care still has *** evidence shows that venous thromboembolism(VTE)is a leading cause of 30-d morbidity and mortality after ***,a clear unmet need exists for a tailored risk assessment tool for VTE in RYGB *** To develop and internally validate a scoring system determining the individualized risk of 30-d VTE in patients undergoing *** Using the 2016–2021 Metabolic and Bariatric Surgery Accreditation Quality Improvement Program,data from 6526 patients(body mass index≥40 kg/m^(2))who underwent RYGB were analyzed.A backward elimination multivariate analysis identified predictors of VTE characterized by pulmonary embolism and/or deep venous thrombosis within 30 d of *** resultant risk scores were derived from the coefficients of statistically significant *** performance of the model was evaluated using receiver operating curves through 5-fold *** Of the 26 initial variables,six predictors were *** included a history of chronic obstructive pulmonary disease with a regression coefficient(Coef)of 2.54(Ph of stay(Coef 0.08,Phrombosis(Coef 1.61,Phemoglobin A1c>7%(Coef 1.19,Phistory(Coef 1.43,Phese variables were weighted according to their regression coefficients in an algorithm that was generated for the model predicting 30-d VTE risk *** risk model's area under the curve(AUC)was 0.79[95%confidence interval(CI):0.63-0.81],showing good discriminatory power,achieving a sensitivity of 0.60 and a specificity of *** training,the same model performed satisfactorily

关键词： Roux-en-Y gastric bypass Venous thromboembolism Machine learning Bariatric surgery Predictive modeling

An efficient approach for solving mixed-integer programming problems under the monotonic condition

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Journal of Control and Decision 2016年第1期3卷 44-67页

作者： Mikhail A.Bragin peter B.Luh Joseph h.Yan Gary A.Stern Department of Electrical and Computer Engineering University of ConnecticutStorrsCTUSA Southern California Edison RosemeadCAUSA

Many important integer and mixed-integer programming problems are difficult to solve.A representative example is unit commitment with combined cycle units and transmission capacity *** transitions within combined cycle units are difficult to follow,and system-wide coupling transmission capacity constraints are difficult to *** example is the quadratic assignment *** presence of cross-products in the objective function leads to *** this study,building upon the novel integration of surrogate Lagrangian relaxation and branch-and-cut,such problems will be solved by relaxing selected coupling *** of the relaxed problem will be assumed and exploited and nonlinear terms will be dynamically *** linearity of the resulting problem will be exploited using *** achieve fast convergence,guidelines for selecting stepsizing parameters will be *** method opens up directions for solving nonlinear mixed-integer problems,and numerical results indicate that the new method is efficient.

关键词： integer monotonic programming mixed-integer monotonic programming branch-and-cut surrogate Lagrangian relaxation