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Worker laying in leafcutter ant Acromyrmex subterraneus brunneus （formicidae, Attini）

Insect Science 2007年第2期14卷 157-163页

作者： ROBERTO S. CAMARGO LUIZ C. fORTI JULIANE f. S. LOPES NEWTON C. NORONHA ANGELO L. T. OTTATI Departamento de Producāo Vegetal FCA/UNESP Botucatu SP Campus Universitário Paulo VI Sāo Luis MA Brazil. Comportamento e Biologia Animal Instituto de Ciencias Biológicas Universidade Federal de Juiz de Fora Campus Universitário Martelos Juiz de Fora MG Campus Universitário Paulo VI Sāo Luis MA Brazil. Departamento de Entomologia Fitopatologia e Zoologia Agricola Escola Superior de Agricultura 'Luiz de Queiroz' Universidade de Sao Paulo Piracicaba SP Campus Universitário Paulo VI Sāo Luis MA Brazil. Departamento de fitotecnia e fitossanidade Universidade Estadual do Maranhāo Centro de Ciencias Agrenias Campus Universitário Paulo VI Sāo Luis MA Brazil.

We studied the process of offspring production in queenless colonies of Acromyrmex subterraneus brunneus, and particularly evaluated the ovary development of workers as a function of their age. for this, subcolonies were set up and evaluated at different periods of isolation from the queen （2, 4 and 6 months）, besides individually labeled age groups. The subcolonies were assessed according to offspring production and ovaries containing oocytes or not. The evaluations showed worker oviposition and development of males originating from worker-laid eggs. At 2 months＇ absence of the queen, eggs and larvae were found, with eggs in a higher proportion than larvae. After 4 months, the proportion of eggs had reduced while larvae had increased, and a pupa was found in one subcolony. At 6 months, besides a higher share of larvae, one pupa and one adult male were found. Dissection of workers revealed ovaries containing oocytes during the periods of evaluation. Only a group of medium-sized and large workers, 23.3%, 20.9% and 37.5% of the population from each period assessed in queenless subcolonies respectively, presented developed oocytes in the ovary. The same was observed in colonies with a queen, with 17.6%, 19.6% and 7.8% of the group of dissected workers from each time period, respectively. With respect to worker age, we observed by dissection of the ovary, that the greatest percentage of individuals with ovarioles containing oocytes occurred at 45 days （6 weeks） up to 90 days （12 weeks）. These results probably are associated with the workers reproduction and the laying of trophic and reproductive eggs in colonies with and without a queen; these eggs have distinct functions in each situation.

关键词： leafcutter ant queenless ant colonies reproduction conflict worker laying,worker reproduction

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Energy Aware Spectrum Access in Cognitive Radio Networks with Imperfect Channel Sensing

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China Communications 2012年第9期9卷 127-130页

作者： Wei Yifei Du Chenhui feng Ruijun f. Richard Yu Beijing University of Posts and Telecommunications Beijing 100876 P. R. China China Mobile Communications Corporation Beijing 100032 P.R. China Department of Systems and Computer Engineering Carleton University Ottawa ON Canada

Due to the problem of spectrum underuti-lization and energy inefficiency in wireless commu-nications, the research on energy efficient Cogni-tive Radio Networks （CRNs） has received signifi-cant attention in both industry and academia. In this paper, we consider the problem of optimal spectrum selection and transmission parameters de-sign with the objective of minimizing energy con-sumption in CRNs. Since the system state cannot be directly observed due to miss detections and estimation errors, we formulate the optimal spec-trum access problem as a Partially Observable Markov Decision Process （POMDP）. In particular, the proposed scheme selects the optimal spectrum, modulation and coding scheme, transmission pow-er, and link layer frame size in each time slot ac-cording to the belief state, which captures all the history information of past actions and observa- tions. The optimal policy can be acquired by sol-ving POMDP problem with linear programming based algorithm Sinmlation results show that sig-nificant energy savings can be achieved by the proposed scheme.

关键词： spectrum access cognitive radio POMDP

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Modelling and optical response of a compressive-strained AlGaN/GaN quantum well laser diode

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Journal of Semiconductors 2020年第6期41卷 29-34页

作者： A.Menani L.Dehimi S.Dehimi f.Pezzimenti Laboratory of Metallic and Semiconducting Materials(LMSM) Department of Electrical EngineeringBiskra UniversityBiskraAlgeria faculty of Science Elhadj Lakhdar UniversityBatnalAlgeria Research Centre in Industrial Technology(CRTI) AlgiersAlgeria DIIES–Mediterranea University of Reggio Calabria Reggio CalabriaItaly

The effects of the quantum well(QW)width,carrier density,and aluminium(Al)concentration in the barrier layers on the optical characteristics of a gallium nitride(GaN)-based QW laser diode are investigated by means of a careful modelling analysis in a wide range of *** device’s optical gain is calculated by using two different band energy *** first is based on the simple band-to-band model that accounts for carrier transitions between the first levels of the conduction band and valence band,whereas the second assumes the perturbation theory(k.p model)for considering the valence intersubband transitions and the relative absorption losses in the *** results reveal that the optical gain increases with increasing the n-type doping density as well as the Al molar fraction of the AlxGa1–xN layers,which originate the GaN compressivestrained *** particular,a significant optical gain on the order of 5000 cm^-1 is calculated for a QW width of 40A at room *** addition,the laser threshold current density is of few tens of A/cm^2 at low temperatures.

关键词： laser diode quantum well optical gain threshold current temperature

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Radioembolization for the treatment of unresectable hepatocellular carcinoma:A clinical review

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World Journal of Gastroenterology 2008年第11期14卷 1664-1669页

作者： Saad M Ibrahim Robert J Lewandowski Kent T Sato Vanessa L Gates Laura Kulik Mary f Mulcahy Robert K Ryu Reed A Omary Riad Salem Department of Radiology Section of Interventional RadiologyNorthwestern MemorialHospitalRobert H.Lurie Comprehensive Cancer CenterChicago60611United States Department of Nuclear Medicine Northwestern Memorial HospitalChicago 60611United States Department of Medicine Division of HepatologyNorthwestern Memorial HospitalChicago 60611United States Department of Medicine Divisionof Hematology and OncologyRobert H Lurie ComprehensiveCancer CenterNorthwestern Memorial HospitalChicago 60611United States Department of Radiology Section of Interventional RadiologyNorthwestern MemorialHospitalRobert H.Lurie Comprehensive Cancer CenterChicago60611United States Department of MedicineDivisionof Hematology and OncologyRobert H Lurie Comprehensive Cancer CenterNorthwestern Memorial HospitalChicago 60611United States

Hepatocellular carcinoma(HCC)is the sixth most common cancer in the *** majority of patients with HCC present with unresectable *** patients have historically had limited treatment options secondary to HCC demonstrating chemoresistance to the currently available systemic ***, normal liver parenchyma has shown intolerance to tumoricidal radiation doses,limiting the use of external beam *** of these limitations,novel percutaneous liver-directed therapies have emerged. The targeted infusion of radioactive microspheres (radioembolization)represents one such therapy. Radioembolization is a minimally invasive transcatheter therapy through which radioactive microspheres are infused into the hepatic arteries that supply tumor. Once infused,these microspheres traverse the hepatic vascular plexus and selectively implant within the tumor *** within the arterioles, the 90Y impregnated microspheres emit high energy and low penetrating radiation doses selectively to the *** has recently shown promise for the treatment of patients with unresectable HCC. The objective of this review article is to highlight twocurrently available radioembolic devices(90Y,188Rh)and provide the reader with a recent review of the literature.

关键词： Radioembolization Brachytherapy Hepatocellular carcinoma Yttrium-90 Rhenium-188

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Crouzon syndrome mouse model exhibits cartilage hyperproliferation and defective segmentation in the developing trachea

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Science China(Life Sciences) 2019年第10期62卷 1375-1380页

作者： Elizabeth A. Hines Mary-Kayt N. Jones Julie f. Harvey Chad Perlyn David M. Ornitz Xin Sun Jamie M. Verheyden Laboratory of Genetics University of WisconsinMadisonWI 53706USA Department of Surgery Florida International University College of MedicineMiamiFL 33199USA Department of Developmental Biology Washington University School of MedicineSt. LouisMO 63110USA Department of Pediatrics University of California-San DiegoLa JollaCA 92093USA

Crouzon syndrome is the result of a gain-of-function point mutation in fGfR2. Mimicking the human mutation, a mouse model of Crouzon syndrome(fgfr2342Y) recapitulates patient deformities, including failed tracheal cartilage segmentation, resulting in a cartilaginous sleeve in the homozygous mutants. We found that the fgfr2C342Y/C^342Y mutants exhibited an increase in chondrocytes prior to segmentation. This increase is due at least in part to over proliferation. Genetic ablation of chondrocytes in the mutant led to restoration of segmentation in the lateral but not central portion of the trachea. These results suggest that in the fgfr2C342Y/C342Y mutants, increased cartilage cell proliferation precedes and contributes to the disruption of cartilage segmentation in the developing trachea.

关键词： trachea lung mouse development

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THE INfLUENCE Of IRRADIATEDWHEAT ON LONGEVITY AND REPRODUCTIONOf THE GRAIN WEEVIL Sitophilus granarius LINNE 1758

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核农学报 1993年第4期 223-226页

作者： V. Arthur,f.M. Wiendl,S.S.H. franco Nuclear Nuclear Nuclear Energy Center for Agriculture University of So Paulo Piracicaba SP. 13400—970 Brazil Energy Center for Agriculture University of So Paulo Piracicaba SP. 13400—970 Brazil Energy Center for Agriculture University of So Paulo Piracicaba SP. 13400—970 Brazil

The main objective of the present research was to determine the influence of gamma irradiations on wheat,the diet of the grain weevil,using as parameters of the longevity and reproduction of this *** doses of 60Coγ-rays applied to wheat grains were O(control),125,250,500,1000,2000,and 4000 Gy,at a dose rate of 3000 Gy per *** longevity,expressed as life-expectancy in days,and the reproduction expressed as the number of f1 adults,showed no differences up to the dose of 2000 *** wheat irradiated with the dose of 4000 Gy induced a lower life-expectancy of the insects fed with irradiated wheat and a smaller number of insects of the f1 generation.

关键词： Wholesomeness of irradiated foods stored grains irradiation radiation grain weevil

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Influence of Re on the Properties of a NiCoCrAlY Coating Alloy

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Journal of Materials Science & Technology 2011年第5期27卷 408-414页

作者： J.J. Liang H. We Y.L. Zhu X.f. Sun Z.Q. Hu M.S. Dargusch X.D. Yao Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences Beijing 100039 China School of Materials & Mining Engineering The University of Queensland QLD 4072 Australia

MCrAIY can serve as stand-alone overlay coatings or bond coats in thermal barrier coating systems, and its properties play a vital role in determining the performance of these coating systems. In order to further understand the behavior of MCrAIY coatings, several NiCoCrAIY model alloys with different levels of Re （0.3 wt%, O wt%, and 9 wt%） were investigated. Microstructural observation showed the addition of Re promoted the precipitation of Cr-rich phases, such as α-Cr and σ. The presence of α-Cr lowered the coefficient of thermal expansion （CTE） of the coating alloys, which could reduce the CTE mismatch at the scale-metal interface. The solid solution strengthening effect of Re is responsible for an increase in Rockwell hardness of the coating alloys. But the isothermal oxidation resistance at 1100℃ was deteriorated due to the precipitation of brittle α-Cr phase, a phase of inferior oxidation resistance compared with β-NiAI and γ-Ni.

关键词： NiCoCrAIY Phase constitution Oxidation Thermal expansion behavior Hardness

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Nuclear Energy for Sustainable Economic Development

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Journal of Water Resource and Protection 2016年第9期8卷 865-872页

作者： f. D’Auria A. Bousbia Salah Dipartimento di Ingegneria Meccanica Nucleare e della Produzione Pisa Italy

The discovery and the application of nuclear energy constitute the most important technological achievement of the past century. However, the development and the exploitation of this technology have been remarkably smaller than foreseeable. An overview of the significant features of the nuclear technology including the comparison with competitive energy sources is made. The “embedded” safety engineering and the pollution are discussed and the main features are mentioned. Indeed, nuclear technology can be applied for the sustainable society development by producing substantial amount of clean water from the ocean. The idea is to build up nuclear power plant sites that produce desalinated water and pump it several tens of kilometers away to form a lake into a desert region. This could help to establish the conditions for an agriculture-based civilization.

关键词： Nuclear Energy Sea Water Desalination Economic Development

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Children’s growth and motor development following a severe burn:a systematic review

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Burns & Trauma 2023年第1期11卷 349-360页

作者： Maxime D.Cuijpers Martin G.A.Baartmans Paul P.M.van Zuijlen Johannes C.f.Ket Anouk Pijpe Red Cross Hospital Burn Centre BeverwijkVondellaan 13BeverwijkThe Netherlands Amsterdam University Medical Centre Location VU University Medical CentreDepartment of PlasticReconstructiveand Hand SurgeryAmsterdam Movement Sciencesde Boelelaan 1117AmsterdamThe Netherlands Association of Dutch Burn Centres Zeestraat 27-29BeverwijkThe Netherlands Maasstad Hospital Department of PaediatricsMaasstadweg 21Rotterdam3079 DZThe Netherlands Red Cross Hospital Department of Plastic SurgeryReconstructive and Hand SurgeryVondellaan 13Beverwijk1942 LEThe Netherlands Paediatric Surgical Centre Emma Children’s HospitalAmsterdam UMCUniversity of AmsterdamVrije UniversiteitMeibergdreef 9Amsterdam1105 AZThe Netherlands Medical Library Vrije Universiteitde Boelelaan 1117AmsterdamThe Netherlands

Background:The epidemiological data on post-burn growth,body composition and motor devel-opment is ambiguous and *** aim of this systematic review was therefore to summarize the current body of evidence on post-burn growth,body composition and motor development in ***:A literature search was conducted in PubMed,EMBASE and Web of Science up to March *** considered observational studies that reported(1)metrics on weight,height,body composition,bone mineral content,bone mineral density or motor development,in(2)paediatric burn patients and(3)published in a peer-reviewed ***:A total of 16 studies were *** of the included studies used quantitative methods,but with differing methodology:prospective cohort studies(n=8),retrospective chart reviews(n=3),case-control studies(n=2),cross sectional studies(n=2)and a retrospective cohort study(n=1).When combined,the included studies represented 2022 paediatric burn patients,with a mean age of 7.7(±3.2)*** average burn sizewas 52.8%(±12.7)of the total body surface *** outcome measures included weight(n=12),height(n=7),muscular strength(n=4),bone mineral content(n=5),bone mineral density(n=5),body mass index(n=3),fat mass(n=5),lean body mass(n=7)and fine and gross motor development(n=1).Conclusions:following an initial decline,patients’growth and motor development started to recover during the first or second year ***,burns may have a profound and prolonged effect on the paediatric burn patients’muscular strength,bone mineral content and lean body *** should be noted that the vast majority of studies included only patients with burns covering≥30%total body surface *** evidence presented in this review may thus not be representative of the whole paediatric burn population.

关键词： Burns Children Weight Height Bone Muscle Motor function

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氟盐冷却高温堆半实物仿真及初步测试

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原子能科学技术 2018年第4期52卷 659-665页

作者：阮见邹杨 KENDRICK J 李明海 PETERSON P f 徐洪杰中国科学院上海应用物理研究所上海201800 中国科学院大学北京100049 University of California Berkeley CA94706USA

基于半实物仿真理论,完善了氟盐冷却高温堆设计Mark-1的缩比模型CIET装置的功能,使该装置更能反映出反应堆运行的特点。借助MATLAB与LabVIEW的串口通信功能,在该装置的控制系统中增加中子动力学模型、反应性反馈模型以及温度控制和功率... 详细信息

基于半实物仿真理论,完善了氟盐冷却高温堆设计Mark-1的缩比模型CIET装置的功能,使该装置更能反映出反应堆运行的特点。借助MATLAB与LabVIEW的串口通信功能,在该装置的控制系统中增加中子动力学模型、反应性反馈模型以及温度控制和功率控制模型,使该装置能模拟Mark-1设计的一回路的运行。温度控制实验的测试结果显示,实验装置的加热器能迅速响应控制器的输出,达到设定的目标温度;通过对点堆功率控制模型的PID参数优化,获得较好的功率控制参数和调控结果,为后续优化控制逻辑、研究参数不确定性影响等奠定基础。

关键词：氟盐冷却高温堆半实物仿真串口通信控制逻辑

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