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Photoluminescence properties of a novel orange-red emitting Ba_2CaZn_2Si_6O_(17):Sm^(3+)phosphor

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journal of Rare Earths 2016年第6期34卷 576-582页

作者： G.Annadurai S.Masilla Moses kennedy V.Sivakumar Department of Physics S.S.N.College of EngineeringRajiv Gandhi SalaiKalavakkam-603 110ChennaiTamil NaduIndia Saveetha Engineering College Thandalam-602105ChennaiIndia

Novel orange-red emitting Ba_2Ca_（1–x）Zn_2Si_6O_（17）：x Sm^（3＋）（0.02≤x≤0.08） phosphors were synthesized using conventional solid-state reaction method under air atmosphere. The phase formation of the samples was characterized by powder X-ray diffraction patterns. Scanning electron microscopy（SEM） and photoluminescence properties were also investigated. The narrow excitation and emission spectra indicated the typical 4f-4f transitions of Sm^（3＋）. The dominant excitation line was around 405 nm attributed to ~6H_（5/2）→ ~4F_（7/2） and the emission spectrum consisted of four emission peaks at 562, 600, 647, and 708 nm corresponding to the various transitions ~4G_（5/2） to ~6Hj（j=5/2, 7/2, 9/2 and 11/2） of the Sm^（3＋） ions in the same order. The strongest emission band located at 600 nm was attributed to ~4G_（5/2）→~6H_（7/2） transition of Sm^（3＋）, producing bright orange-red color emission. The optimal dopant concentration of Sm3＋ ion in Ba_2CaZn_2Si_6O_（17）：x Sm^（3＋） phosphor was around 4 mol.% and the critical transfer distance（Rc） of Sm^（3＋） was calculated to be 2.65 nm. Decay time varied with the Sm^（3＋） concentrations in Ba_2 CaZn_2Si_6O_（17） phosphors. In addition, the Commission International del＇Eclairagethe（CIE） chromaticity coordinates of Ba_2Ca_（0.96）Zn_2Si_6O_（17）：0.04Sm^（3＋） phosphor was located in the orange-red region（0.547, 0.450） and the correlated color temperature（CCT） was 2543 K. The present results indicated that Sm^（3＋） activated Ba_2CaZn_2Si_6O_（17） phosphors may be used as an orange-red emitting phosphor for near-ultraviolet（n-UV） based white light emitting diodes（WLEDs） applications.

关键词： Sm^(3+) phosphors photoluminescence WLEDs rare earths

Controlling schistosomiasis with praziquantel:How much longer without a viable alternative?

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Infectious Diseases of Poverty 2017年第1期6卷 654-663页

作者： robert Bergquist jürg Utzinger jennifer Keiser Ingerod BrastadSweden Swiss Tropical and Public Health Institute P.O.BoxCH-4002 BaselSwitzerland University of Basel P.O.BoxCH-4003 BaselSwitzerland

The current approach of morbidity control of schistosomiasis,a helminth disease of poverty with considerable public health and socioeconomic impact,is based on preventive chemotherapy with *** is a pressing need for new drugs against this disease whose control entirely depends on this single drug that has been widely used over the past 40 *** argue that a broader anthelminthic approach supplementing praziquantel with new antischistosomals targeting different parasite development stages would not only increase efficacy but also reduce the risk for drug *** drugs already approved for other diseases provides a shortcut to clinical trials,as it is expected that such drugs rapidly pass the regulatory *** antischistosomal properties of antimalarial drugs(e.g.,semisynthetic artemisinins,synthetic trioxolanes,trioxaquines and mefloquine)and of drugs being developed or registered for other purposes(e.g.,moxidectin and miltefosin),administered alone or in combination with praziquantel,have been tested in the laboratory and clinical *** avenue to follow is the continued search for new antischistosomal properties in ***,we summarise recent progress made in schistosomiasis chemotherapy,placing particular emphasis on repositioning of existing drugs against schistosomiasis.

关键词： Chemotherapy Drug repositioning Elimination Morbidity control Praziquantel Schistosomiasis

Are sperm capacitation and apoptosis the opposite ends of a continuum driven by oxidative stress？

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Asian journal of Andrology 2015年第4期17卷 633-639页

作者： robert j Aitken Mark A Baker Brett Nixon Priority Research Centre in Reproductive Science Discipline of Biological Sciences and Hunter Medical Research Institute University of Newcastle NSW 2308 Australia.

This chapter explores the possibility that capacitation and apoptosis are linked processes joined by their common dependence on the continued generation of reactive oxygen species （ROS）. According to this model capacitation is initiated in spematozoa following their release into the female reproductive tract as a consequence of intracellular ROS generation, which stimulates intracellular cAMP generation, inhibits tyrosine phosphatase activity and enhances the formation of oxysterols prior to their removal from the sperm surface by albumin. The continued generation of ROS by capacitating populations of spermatozoa eventually overwhelms the limited capacity of these cells to protect themselves from oxidative stress. As a result the over-capacitation of spermatozoa leads to a state of senescence and the activation of a truncated intrinsic apoptotic cascade characterized by enhanced mitochondrial RO$ generation, lipid peroxidation, motility loss, caspase activation and phosphatidylserine externalization. The latter may be particularly important in instructing phagocytic leukocytes that the removal of senescent, moribund spermatozoa should be a silent process unaccompanied by the generation of proinflammatory cytokines. These observations reveal the central role played by redox chemistry in defining the life and death of spermatozoa. A knowledge of these mechanisms may help us to engineer novel solutions to both support and preserve the functionality of these highly specialized cells.

关键词： apoptosis reactive oxygen species sperm capacitation

Adding Value to Crop Production Systems by Integrating Forage Cover Crop Grazing

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American journal of Plant Sciences 2024年第3期15卷 180-192页

作者： robert B. Mitchell Daren D. Redfearn Kenneth P. Vogel Terry j. Klopfenstein Galen Erickson P. Stephen Baenziger Bruce E. Anderson Mary E. Drewnoski jay Parsons Steven D. Masterson Marty R. Schmer Virginia L. jin USDA-ARS Wheat Sorghum and Forage Research Unit University of Nebraska-Lincoln Lincoln NE USA Department of Agronomy and Horticulture University of Nebraska-Lincoln Lincoln NE USA Department of Animal Science University of Nebraska-Lincoln Lincoln NE USA Department of Agricultural Economics University of Nebraska-Lincoln Lincoln NE USA USDA-ARS Agroecosystem Management Research Unit University of Nebraska-Lincoln Lincoln NE USA

In addition to their value as cereal grains, wheat (Triticum aestivum L.) and triticale (× Triticosecale Wittmack) are important cool-season annual forages and cover crops. Yearling steer (Bos taurus) performance was compared in the spring following autumn establishment as for age cover crops after soybean [Glycine max (L.) Merr.] grain harvest. Replicated pastures (0.4 ha) were no-till seeded in three consecutive years into soybean stubble in autumn, fertilized, and grazed the following spring near Ithaca, NE, USA. Each pasture (n = 3) was continuously stocked in spring with four yearling steers (380 ± 38 kg) for 17, 32, and 28 d in 2005, 2006, and 2007, respectively. In 2005, average daily gain (ADG) for steers grazing triticale exceeded the ADG for wheat by 0.31 kghd-1d-1. In 2006, wheat ADG exceeded that for triticale by 0.12 kghd-1d-1. In 2007, steers grazing wheat lost weight, while steers grazing triticale gained 0.20 kghd-1d-1. Based on the 3-year average animal gains valued at $1.32 kg-1, mean net return ($ ha-1 yr-1) was $62.15 for triticale and $22.55 for wheat. Since these grazed cover crops provide ecosystem services in addition to forage, grazing could be viewed as a mechanism for recovering costs and adds additional value to the system. Based on this 3-year grazing trial, triticale was superior to wheat and likely will provide the most stable beef yearling performance across years with variable weather for the western Cornbelt USA.

关键词： Cover crops Soybean Triticale Wheat

糖尿病相关的足病的定义和标准(2023年更新版)

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感染、炎症、修复 2024年第1期25卷 80-85页

作者： jaap j.van Netten Sicco A.Bus jan Apelqvist Pam Chen Vivienne Chuter robert Fitridge Frances Game robert j.Hinchliffe Peter A.Lazzarini joseph Mills Matilde Monteiro-Soares Edgar j.G.Peters Katherine M.Raspovic Eric Senneville Dane K.Wukich Nicolaas C.Schaper on behalf of the International Working Group on the Diabetic Foot 张会峰(译) 许樟荣(审校) Department of Rehabilitation Medicine Amsterdam UMCLocation University of AmsterdamAmsterdamthe Netherlands Amsterdam Movement Sciences Program RehabilitationAmsterdamthe Netherlands Department of Endocrinology University Hospital of MalmöMalmöSweden joondalup Health Campus Ramsay HealthcareSydneyAustralia Faculty of Health University of TasmaniaHobartAustralia School of Health Sciences Western Sydney UniversitySydneyAustralia Faculty of Health and Medical Sciences University of AdelaideAdelaideAustralia Vascular and Endovascular Service Royal Adelaide HospitalAdelaideAustralia Department of Diabetes and Endocrinology University Hospitals of Derby and Burton NHS Foundation TrustDerbyUK Department of Vascular Surgery University of BristolBristolUK School of Public Health and Social Work Queensland University of TechnologyBrisbaneAustralia Allied Health Research Collaborative The Prince Charles HospitalBrisbaneAustralia Michael E.DeBakey Department of Surgery Division of Vascular Surgery and Endovascular TherapyBaylor College of MedicineHoustonTexasUSA Portuguese Red Cross School of Health–Lisbon LisbonPortugal MEDCIDS–Departamento de Medicina da Comunidade Informação e Decisão em Saúde Faculty of Medicine of the University of PortoPortoPortugal RISE@CINTESIS Faculty of Medicine Oporto UniversityPortoPortugal Department of Internal Medicine Amsterdam UMCVrije Universiteit AmsterdamSection of Infectious DiseasesAmsterdamthe Netherlands Department of Orthopaedic Surgery University of Texas Southwestern Medical CenterDallasTexasUSA Department of Infectious Diseases Gustave Dron Hospital Tourcoing Univ-lilleTourcoingFrance Div.Endocrinology MUMC+CARIM and CAPHRI InstituteMaastrichtThe Netherlands 不详河南省人民医院内分泌科河南郑州450003 战略支援部队特色医学中心北京100101

糖尿病相关的足病管理涉及多个学科,通用的专业词汇对于各学科间准确沟通交流至关重要。国际糖尿病足工作组(IWGDF)对相关文献进行了系统综述,构成了制定IWGDF指南的基础,并且明确了糖尿病相关的足病的一系列定义、标准及名词解释。本... 详细信息

糖尿病相关的足病管理涉及多个学科,通用的专业词汇对于各学科间准确沟通交流至关重要。国际糖尿病足工作组(IWGDF)对相关文献进行了系统综述,构成了制定IWGDF指南的基础,并且明确了糖尿病相关的足病的一系列定义、标准及名词解释。本文介绍2023年IWGDF对这些定义和标准的更新,并建议在临床实践和研究中一致使用,以利于世界各地不同学科人员针对糖尿病相关的足病的专业性交流。

关键词：定义糖尿病糖尿病相关的足病国际糖尿病足工作组

Choledocholithiasis: Evolving standards for diagnosis and management

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World journal of Gastroenterology 2006年第20期12卷 3162-3167页

作者： Marilee L Freitas robert L Bell Andrew j Duffy Department of Surgery Yale University School of Medicine 40 Temple StreetSuite 3 ANew HavenCT 06510United States

Cholelithiasis, one of the most common medical conditions leading to surgical intervention, affects approximately 10 % of the adult population in the United States. Choledocholithiasis develops in about 10%-20% of patients with gallbladder stones and the literature suggests that at least 3%-10% of patients undergoing cholecystectomy will have common bile duct （CBD） stones. CBD stones may be discovered preoperatively, intraoperatively or postoperatively Multiple modalities are available for assessing patients for choledocholithiasis including laboratory tests, ultrasound, computed tomography scans （CT）, and magnetic resonance cholangiopancreatography （MRCP）. Intraoperative cholangiography during cholecystectomy can be used routinely or selectively to diagnose CBD stones. The most common intervention for CBD stones is ERCP. Other commonly used interventions include intraoperative bile duct exploration, either laparoscopic or open. Percutaneous, transhepatic stone removal other novel techniques of biliary clearance have been devised. The availability, of equipment and skilled practitioners who are facile with these techniques varies among institutions. The timing of the intervention is olden dictated by the clinical situation.

关键词： Choledocholithiasis Laparoscopy Diagnosis Treatment Cholangiogram

Evolution of surgical skills training

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World journal of Gastroenterology 2006年第20期12卷 3219-3224页

作者： Kurt E roberts robert L Bell Andrew j Duffy Department of Surgery Yale University School of Medicine 40 Temple StreetSuite 3ANew HavenCT 06510United Staets

Surgical training is changing： one hundred years of tradition is being challenged by legal and ethical concerns for patient safety, work hours restrictions, the cost of operating room time, and complications. Surgical simulation and skills training offers an opportunity to teach and practice advanced skills outside of the operating room environment before attempting them on living patients. Simulation training can be as straight forward as using real instruments and video equipment to manipulate simulated ＂tissue＂ in a box trainer. More advanced, virtual reality simulators are now available and ready for widespread use. Early systems have demonstrated their effectiveness and discriminative ability. Newer systems enable the development of comprehensive curricula and full procedural simulations. The Accreditation Council of Graduate Medical Education＇s （ACGME） has mandated the development of novel methods of training and evaluation. Surgical organizations are calling for methods to ensure the maintenance of skills, advance surgical training, and to credential surgeons as technically competent. Simulators in their current form have been demonstrated to improve the operating room performance of surgical residents. Development of standardized training curricula remains an urgent and important agenda, particularly for minimal invasive surgery. An innovative and progressive approach, borrowing experiences from the field of aviation, can provide the foundation for the next century of surgical training, ensuring the quality of the product. As the technology develops, the way we practice will continue to evolve, to the benefit of physicians and patients.

关键词： Surgery Training Certification Skills Simulation Curriculum

Crop Epigenomics： Identifying, Unlocking, and Harnessing Cryptic Variation in Crop Genomes

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Molecular Plant 2015年第6期8卷 860-870页

作者： Lexiang ji Drexel A. Neumann robert j. Schmitz Department of Genetics University of Georgia Athens GA 30602 USA Institute of Bioinformatics University of Georgia Athens GA 30602 USA These authors contributed equally to this article.

DNA methylation is a key chromatin modification in plant genomes that is meiotically and mitotically her- itable, and at times is associated with gene expression and morphological variation. Benefiting from the increased availability of high-quality reference genome assemblies and methods to profile single-base res- olution DNA methylation states, DNA methylomes for many crop species are available. These efforts are making it possible to begin answering crucial questions, including understanding the role of DNA methyl- ation in developmental processes, its role in crop species evolution, and whether DNA methylation is dynamically altered and heritable in response to changes in the environment. These genome-wide maps provide evidence for the existence of silent epialleles in plant genomes which, once identified, can be tar- geted for reactivation leading to phenotypic variation.

关键词： epigenomics DNA methylation whole-genome bisulfite sequencing (WGBS) crops comparativegenomics

Controversies in the treatment of gastroesophageal reflux and achalasia

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World journal of Gastroenterology 2006年第20期12卷 3155-3161页

作者： Kurt E roberts Andrew j Duffy robert L Bell Department of Surgery Yale University School of Medicine 40 Temple St. Suite 3 ANew HavenCT 06510United States

The immense success of laparoscopic surgery as an effective treatment of gastroesophageal reflux disease （GERD） and achalasia has established minimal invasive surgery as the gold standard for these two conditions with lower morbidity and mortality, shorter hospital stay, faster convalescence, and less postoperative pain. One controversy in the treatment of GERD evolves around laparoscopic antireflux surgery （LAP, S） as the preferred treatmerit for Barrett＇s esophagus and the procedure＇s potential to reduce the risk of adenocarcinoma of the esophagus. GERD has also been associated with respiratory symptoms, asthma and laryngeal injury, and a second controversy prompts discussions about whether total or partial fundoplication is the more appropriate treatment for GERD. A new and promising alternative in the treatment of GERD is endoluminal therapy. Three types of this new treatment option will be discussed： radiofrequency energy delivered to the lower esophageal sphincter, the creation of a mechanical barrier at the gastroesophageal junction, and the direct endoscopic tightening of the lower esophageal sphincter. Laparoscopic surgery is discussed not only as a very effective treatment for GERD but also as permanent cure for achalasia. This review analyzes the three most important treatment options for achalasia： medications, pneumatic dilatation, and surgical therapy. Medications as the only true non-invasive option in the treatment of achalasia are not as effective as LAPS because of their short half-life and variable absorption due to the poor esophageal emptying. The second treatment option, pneumatic dilatation, involves the stretching of the lower esophagus and is still considered the most effective nonsurgical treatment for achalasia. Finally, surgical therapy for achalasia and the two major controversies concerning this laparoscopic treatment are discussed. The first involves the extent to which the myotomy is extended onto the stomach, and the second concer

关键词： Gastroesophageal reflux disease Nissen Toupet Fundoplication Achalasia Heller myotomy