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Diapause development in early and late emerging phenotypes of Delia floralis

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Insect Science 2014年第1期21卷 103-113页

作者： Tor J. Johansen richard Meadow Arctic Agriculture and Land Use Division Bioforsk - Norwegian Institute for Agricultural and Environmental Research Tromsm plant Health and Plant Protection Division Bioforsk - Norwegian Institute for Agricultural and Environmental Research As Norway

The turnip fly, Delia floralis Fall6n （Diptera： Anthomyiidae） is an important insect pest of brassica vegetable crops in the holarctic region. Different populations have strongly varying temperature requirements for fly emergence, a challenge for accurate prediction of activity. This study focused on diapause development in one early and one late emerging phenotype. The physiological state after various treatments was deduced from emergence data. Our results showed a slow diapause progression at chilling conditions for both populations and diapause ended about 7 months after pupae were formed for the early population. For the late population held at 4℃ diapause did not end, no matter how long the duration of chilling. These pupae required a period with elevated temperatures above 6~C to continue development. At constant non-chilling conditions （18℃） from the time pupae were formed both populations completed diapause most rapidly. These results indicate that chilling delayed, rather than accelerated development and was not a prerequisite for diapause development. For post-diapause, results indicated a linear relationship between rate of development and temperature within the range of 6-18℃and a theoretical base temperature for development of about 2℃ for both populations. In conclusion, D. floralis pupae are in diapause throughout a long winter period, and delayed emergence of the late population appears to be caused by prolonged diapause regulated by a developmental temperature threshold. The study has added information on the biology of turnip fly populations, a prerequisite for improved pest control.

关键词： brassica chilling emergence hibernation quiescence

The Long-term Survival Chances of Young Massive Star Clusters

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Chinese Journal of Astronomy and Astrophysics 2007年第2期7卷 155-186页

作者： richard de Grijs Geneviève Parmentier Department of Physics & Astronomy The University of Sheffield Hicks Building Hounsfield Road Sheffield S3 7RH U. K.National Astronomical Observatories Chinese Academy of SciencesBeijing 100012 Institute of Astrophysics & Geophysics Université de LiègeAllée du 6 Aot17Sart-Tilman (B5c)B-4000 LiègeBelgium

We review the long-term survival chances of young massive star clusters （YMCs）, hallmarks of intense starburst episodes often associated with Violent galaxy interactions. We address the key question as to whether at least some of these YMCs can be considered protoglobular clusters （GCs）, in which case these would be expected to evolve into counterparts of the ubiquitous old GCs believed to be among the oldest galactic building blocks. In the absence of significant external perturbations, the key factor determining a cluster＇s long-term survival chances is the shape of its stellar initial mass function （IMF）. It is, however, not straightforward to assess the IMF shape in unresolved extragalactic YMCs. We discuss in detail the promise of using high-resolution spectroscopy to make progress towards this goal, as well as the numerous pitfalls associated with this approach. We also discuss the latest progress in worldwide efforts to better understand the evolution of entire cluster systems, the disruption processes they are affected by, and whether we can use recently gained insights to determine the nature of at least some of the YMCs observed in extragalactic starbursts as proto-GCs. We conclude that there is an increasing body of evidence that GC formation appears to be continuing until today; their long-term evolution crucially depends on their environmental conditions, however.

关键词： stellar dynamics - globular clusters general - galaxies interactions - Magellanic Clouds - galaxies starburst - galaxies star clusters

Novel Membranes Regenerated from Blends of Cellulose/Gluten Using Ethylenediamine/Potassium Thiocyanate Solvent System

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Journal of Renewable Materials 2019年第1期7卷 41-55页

作者： Yang Yu Ramiz Boy richard Kotek Fiber and Polymer Science Program College of TextilesNorth Carolina State UniversityRaleighNC 27606USA Department Textile Engineering Çorlu Faculty of EngineeringTekirdağNamık Kemal UniversityTekirdağ59860TURKEY

Current industrial methods for dissolution of cellulose in making regenerated cellulose products are relatively expensive,toxic and dangerous and have environmental problems coming with the hazard chemical *** solve these problems,a novel ethylenediamine and potassium thiocyanate(ED/KSCN)solvent system was developed,that is economical,ecofriendly,and highly *** ED/KSCN solvent system was proven to be a suitable solvent for fabricating cellulose(blended with other polymers)*** this study,gluten was used to develop nonporous membranes with *** method of casting these membranes provided better ones than the former researchers’*** composite membranes’physical and mechanical properties were studied by analysis of morphology,viscosity,crystallinity,thermal behaviors,tensile properties and water absorption of *** showed that membranes are nonporous,uniform,strong,flexible,ecofriendly and *** and physical properties were influenced by the ratio of cellulose/*** blending 40% gluten,the tensile strength of cellulose membrane dropped to 15.89 MPa from 35.11 ***,its elongation at break increased from 35.3% to 57.02% accordingly.

关键词： Cellulose gluten blended film novel ED/KSCN solvent physical and mechanical properties

What we have learned from randomized trials of prostate cancer screening

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Asian Journal of Andrology 2011年第3期13卷 369-373,510页

作者： richard M Hoffman Anthony Y Smith Medicine Service New Mexico VA Health Care System Albuquerque NM 87108 USA Department of Medicine University of New Mexico School of Medicine Albuquerque NM 87108 USA Department of Surgery University of New Mexico School of Medicine Albuquerque NM 87108 USA

The introduction of prostate-specific antigen （PSA） for prostate cancer screening in the late 1980s led to an epidemic of prostate cancer, particularly in developed countries. However, the first valid reports from randomized controlled trials on the efficacy of screening were not published until 2009. Men in the screening group in the European Randomized Study of Screening for Prostate Cancer were 20% less likely than those in the control group to die from prostate cancer. The absolute difference was only 0.7/1000, implying that over 1400 men needed to be screened to prevent one prostate cancer death. Screening was also associated with a 70% increased risk for being diagnosed with prostate cancer. The American Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial found no survival benefit for screening. Results were not conclusive because a substantial proportion of study subjects had previously undergone PSA testing, over half of the control group had PSA testing, follow-up was relatively short, and fewer than 100 subjects died from prostate cancer. Balancing the potential survival benefit from screening is the risk of overdiagnosis--finding cancers that would not otherwise cause clinical problems^and the risk of treatment complications, including urinary, sexual and bowel dysfunction. Prostate cancer screening efforts would benefit from improved biomarkers, which more readily identify clinically important cancers. Cancer control efforts might also need to include chemoprevention, though currently available agents are controversial. In the meantime, oatients need to be supoorted in achievine informed decisions on whether to be screened for orostate cancer.

关键词： cancer screening prostate-specific antigen prostatic neoplasms randomized controlled trials as topic

Is a mirror necessary for mirror therapy?

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Neural Regeneration Research 2023年第12期18卷 2703-2704页

作者： richard G.Carson Alannah Morley Trinity College Institute of Neuroscience and School of Psychology Trinity College DublinDublinIreland Dublin Ireland(Carson RG)School of PsychologyQueen’s University BelfastBelfastNorthern IrelandUK(Carson RG)School of MedicineTrinity College DublinDublinIreland

Since it was first described as a method to treat phantom limb pain, mirror therapy(MT) has been applied in many areas of rehabilitation. Its seminal application with the aim of restoring motor function following stro... 详细信息

关键词： mirror al. therapy

Near-infrared Emissive 1,2-Dioxetane-based Chemiluminescent Probes

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Chemical Research in Chinese Universities 2024年第5期40卷 806-823页

作者： CHEN Yingqi BUDIANTA richard NING Yingying Spin-X Institute School of Chemistry and Chemical EngineeringSchool of Biomedical Sciences and EngineeringState Key Laboratory of Luminescent Materials and DevicesGuangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional MaterialsSouth China University of TechnologyGuangzhou510641P.R.China

Chemiluminescence,a phenomenon emitting light from chemical reactions rather than photon absorption,has gained significant interest for applications in bioimaging and biosensing due to its high sensitivity and low background *** there is a growing interest in near-infrared(NIR)chemiluminescent probes for improved tissue penetration and reduced *** review summarizes NIR emissive chemiluminescent probes based on 1,2-dioxetane and discusses their chemical structures and *** modification strategies for red-shifting wavelength and enhancing brightness include incorporating electron-withdrawing groups,designing chemiluminophore-fluorophore cassettes,and exploring alternative chemiluminescent *** review aims to inspire the exploration of NIR chemiluminescent probes in disease detection and treatment.

关键词： Chemiluminescence Near-infrared Dioxetane Bioimaging Biosensing

Carboxylesterases in lipid metabolism： From mouse to human

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Protein & Cell 2018年第2期9卷 178-195页

作者： Jihong Lian Randal Nelson richard Lehner Group on Molecular and Cell Biology of Lipids University of Alberta Edmonton Alberta Canada Department of Pediatrics University of Alberta Edmonton Alberta Canada Department of Cell Biology University of Alberta Edmonton Alberta Canada

Mammalian carboxylesterases hydrolyze a wide range of xenobiotic and endogenous compounds, including lipid esters. Physiological functions of car- boxylesterases in lipid metabolism and energy home- ostasis in vivo have been demonstrated by genetic manipulations and chemical inhibition in mice, and in vitro through （over）expression, knockdown of expression, and chemical inhibition in a variety of cells. Recent research advances have revealed the relevance of carboxylesterases to metabolic diseases such as obesity and fatty liver disease, suggesting these enzymes might be potential targets for treatment of metabolic disorders. In order to translate pre-clinical studies in cellular and mouse models to humans, dif- ferences and similarities of carboxylesterases between mice and human need to be elucidated. This review presents and discusses the research progress in structure and function of mouse and human car- boxylesterases, and the role of these enzymes in lipid metabolism and metabolic disorders.

关键词： carboxylesterase lipase lipid lipoprotein iver adipose intestine

The good and evil of complement activation in HIV-1 infection

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Cellular & Molecular Immunology 2010年第5期7卷 334-340页

作者： Qigui Yu richard Yu Xuebin Qin Department of Microbiology and Immunology University School of Medicine635 Barnhill DriveIndianapolisINUSA Harvard Medical School Laboratory for Translational ResearchCambridgeMAUSA

The complement system,a key component of innate immunity,is a first-line defender against foreign pathogens such as *** role of the complement system in HIV-1 pathogenesis appears to be *** the complement system plays critical roles in clearing and neutralizing HIV-1 virions,it also represents a critical factor for the spread and maintenance of the virus in the infected *** addition,complement regulators such as human CD59 present in the envelope of HIV-1 prevent complement-mediated lysis of *** novel approaches are proposed to combat HIV-1 infection through the enhancement of antibody-dependent complement activity against *** this paper,we will review these diverse roles of complement in HIV-1 infection.

关键词： antibody complement HIV-1 human CD59

Preventative medicine and Alzheimer's disease: is Alzheimer's disease risk reduction achievable?

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Neural Regeneration Research 2021年第9期16卷 1772-1773页

作者： Benjamin Sinyor richard Isaacson Christopher Ochner HCA Healthcare NashvilleTNUSA Weil Cornell Medicine New York Presbyterian HospitalNew YorkNYUSA

Alzheimer 's disease(AD) has a multifactorial etiology that has eluded scientists and clinicians for decades. This incomplete understanding of the causal factors likely contributes to the dearth of effective therapeut... 详细信息

关键词： Alzheimer elude likely