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A systematic review and meta-analysis to determine the effect of sperm DNA damage on in vitro fertilization and intracytoplasmic sperm injection outcome

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Asian Journal of Andrology 2017年第1期19卷 80-90页

作者： Luke Simon Armand Zini Alina Dyachenko Antonio Ciampi douglas T Carrell Department of Surgery (Urology) University of Utah School of Medicine Salt Lake City UT USA Division of Urology Department of Surgery St. Mary's Hospital Center St. Mary's Hospital 3830 Lacombe Avenue Montreal Quebec H3T 1M5 Canada Department of Human Genetics University of Utah School of Medicine Salt Lake City UT USA Department of Obstetrics and Gynecology University of Utah School of Medicine Salt Lake City UT USA.

Sperm DNA damage is prevalent among infertile men and is known to influence natural reproduction. However, the impact of sperm DNA damage on assisted reproduction outcomes remains controversial. Here, we conducted a meta-analysis of studies on sperm DNA damage （assessed by SCSA, TUNEL, SCD, or Comet assay） and clinical pregnancy after IVF and/or ICSI treatment from MEDLINE, EMBASE, and PUBMED database searches for this analysis. We identified 41 articles （with a total of 56 studies） including 16 IVF studies, 24 ICSI studies, and 16 mixed （IVF ＋ ICSI） studies. These studies measured DNA damage （by one of four assays： 23 SCSA, 18 TUNEL, 8 SCD, and 7 Comet） and included a total of 8068 treatment cycles （3734 IVF, 2282 ICSI, and 2052 mixed IVF ＋ ICSI）. The combined OR of 1.68 （95% Ch 1.49-1.89; P 〈 0.0001） indicates that sperm DNA damage affects clinical pregnancy following IVF and/or ICSI treatment. In addition, the combined OR estimates of IVF （16 estimates, OR = 1.65; 95% CI： 1.34-2.04; P 〈 0.0001）, ICSI （24 estimates, OR = 1.31; 95% Ch 1.08-1.59; P = 0.0068）, and mixed IVF ＋ ICSI studies （16 estimates, OR = 2.37; 95% Ch 1.89-2.97; P〈 0.0001） were also statistically significant. There is sufficient evidence in the existing literature suggesting that sperm DNA damage has a negative effect on clinical pregnancy following IVF and/or ICSI treatment.

关键词： assisted reproductive technology outcomes clinical pregnancy meta-analysis sperm DNA damage systematic review

Blockchains for constrained edge devices

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Blockchain(Research and Applications) 2020年第1期1卷 37-43页

作者： Antonyo douglas Richard Holloway Jonathan Lohr Elijah Morgan Khaled Harfoush Department of Computer Science North Carolina State University Raleigh NC27606USA Department of Electrical and Computer Engineering North Carolina State University RaleighNC27606USA

Today’s networks are seeing a large influx of Internet connected devices that reside primarily on the edge of the *** of these devices,such as Internet of Things(IoT)devices,are resource constrained both by storage capacity and power requirements that limit a device’s Internet *** interesting architectures have been proposed to address security,device management,configuration,and multi-party interaction concerns using blockchain *** architectures require a trusted intermediary to interact with the blockchain on behalf of the edge *** introduces a single point of failure in trust and *** paper proposes a novel adaptation of blockchain technology to enable these edge devices to interact and participate with a blockchain without requiring a trusted *** proposed architecture provides a flexible and extensible framework that enables multi party interactions to take place at the edge of the *** efficacy of the proposed design is demonstrated through theoretical analysis and by an application to a network of resource constrained IoT devices.

关键词： Blockchains Internet of Things Wireless Communication

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改造大气:一场降温豪赌?

环球科学 2024年第1期 44-51页

作者：道格拉斯·福克斯杜怡心(翻译) 闻新宇(审校) 不详

面对全球变暖的严峻形势,一些科学家提出,是时候改造我们头顶的天空了。2023年2月12日,一个凉爽的下午,两名男子将一辆房车停在美国内华达州里诺市外的一片田野旁。他们在便携式烧烤架上点燃了拳头大小的一堆黄色硫粉,空气中很快弥漫开... 详细信息

面对全球变暖的严峻形势,一些科学家提出,是时候改造我们头顶的天空了。2023年2月12日,一个凉爽的下午,两名男子将一辆房车停在美国内华达州里诺市外的一片田野旁。他们在便携式烧烤架上点燃了拳头大小的一堆黄色硫粉,空气中很快弥漫开一股臭鸡蛋的气味一一这是无色的二氧化硫(SO_(2))气体的味道。

关键词：内华达州全球变暖二氧化硫改造

Human protamines and the developing spermatid: their structure, function, expression and relationshipwith male infertility

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Asian Journal of Andrology 2003年第4期5卷 315-324页

作者： Vincent W. Aoki douglas T. Carrell Andrology and IVF Laboratories University of Utah School of Medicine Salt Lake City UT 84108 USAAndrology and IVF Laboratories University of Utah School of Medicine Salt Lake City UT 84108 USA

During spermiogenesis, the protamine proteins play an integral role in spermatid chromatin compaction. Recent research has focused on many facets of protamine biology, including protamine gene and protein structure/ function relationships, mechanisms of protamine expression regulation and involvement of the protamines in male fertility. In this paper, we review our current understanding of the structure and function of the protamine-1 (P1) and protamine-2 (P2) proteins and genes, the expression and regulation of these genes and the relationship between the protamines and male fertility. In addition, we offer a brief outlook on future investigation into protamine proteins.

关键词： protamines spermatids male infertility spermatid transition proteins

Hadron resonances as rovibrational states

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Chinese Physics C 2021年第8期45卷 99-104页

作者： douglas L.Bernardo Cristiano C.Bastos Antonio C.Pavao Departamento de Quimica Fundamental Universidade Federal de PernambucoRecife50740-540Brazil Departamento de Quimica Universidade Federal Rural de PernambucoRecife52171-900Brazil

A rovibrational model,including anharmonic,centrifugal,and Coriolis corrections,is used to calculate π,K,N,and ∑ orbital and radial *** four orbital excitations of the n meson correspond to the/?(1235),ti2(1670),63(2030),and π4(2250)*** first four radial excitations correspond to the π(1300),π(1800),π(2070),and 7t(2360)*** orbital excitations of the K meson are interpreted as the K_(1)(1270),K_(2)(1770),K_(3)(2320),and K_(4)(2500)resonances;its radial excitations correspond to the K(1460)and K(1830)*** N orbital excitations are identified with the N(1520),N(1680),N(2190),N(2220),and N(2600)*** first four radial excitations of the N family correspond to the N(1440),N(1880),N(2100),and N(2300)*** orbital excitations of the ∑ baryon are associated with the ∑(1670),∑(1915),∑(2100),and ∑(2250)resonances,whereas its radial excitations are identified with the ∑(1660),∑(1770),and ∑(1880)*** proposed rovibrational model calculations show a good agreement with the corresponding experimental values and allow for the prediction of hadron resonances,thereby proving to be useful for the interpretation of excited hadron spectra.

关键词： excited hadron spectrum orbital and radial resonances rovibrational states

Contributions of forensic anthropology to positive scientific identification:a critical Review

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Forensic Sciences Research 2019年第1期4卷 45-50页

作者： douglas H.Ubelaker Austin Shamlou Amanda Kunkle Department of Anthropology Smithsonian InstitutionWashingtonDCUSA

This review covers previous and current literature on the impact of forensic anthropologists on the positive scientific identification of human remains and aims to provide an under-standing of what information a forensic anthropologist can contribute to an investigation. Forensic anthropologists looking to identify human remains study traits of the skeleton and any orthopedic devices present. In order to obtain a positive scientific identification, evi-dence that is both sufficiently unique to the individual and comparable to available ante-mortem data from that individual must be found. The increased availability of radiographs, scans and implants in recent decades has facilitated the identification process. When these records are unavailable, other techniques, such as craniofacial superimposition and facial approximation, can be employed. While these methods may assist the identification process, they are most useful for exclusion of certain individuals and gathering leads from the public. Forensic anthropologists have heavily relied on the skull and its complexities for identifica-tion – typically focusing on the frontal sinus and other unique traits. Post-cranial remains can provide important information about bone density, possible disease and other character-istics that may also be utilized. Techniques used to positively identify individuals are not limited to medicolegal death investigations, and have been useful in other legal contexts. In the future, a team approach, utilizing all the information gathered by multiple forensic scientists–including forensic anthropologists–will most likely become more common.

关键词： Forensic sciences forensic anthropology positive scientific identification medicolegal death investigation craniofacial superimposition facial approximation team approach

Effects of silver adsorbed on fumed silica,silver phosphate glass,bentonite organomodified with silver and titanium dioxide in aquatic indicator organisms

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Journal of Environmental Sciences 2017年第6期29卷 230-239页

作者： Daiane Tomacheski Michele Pittol douglas Naue Simoes Vanda Ferreira Ribeiro Ruth Marlene Campomanes Santana Department of Materials Engineering Laboratory of Polymers-LAPOLUniversidade Federal do Rio Grande do SulPorto Alegre 91501-970Brazil Softer Brasil Cornpostos Termopldsticos Carnpo Born 93700-000Brazil

In order to reduce the level of transmission of diseases caused by bacteria and fungi, the development of antimicrobial additives for use in personal care, hygiene products, clothing and others has increased. Many of these additives are based on metals such as silver and titanium. The disposal of these products in the environment has raised concerns pertaining to their potential harmfulness for beneficial organisms. The objective of this study was to evaluate the influence of the shape, surface chemistry, size and carrier of three additives containing silver and one with titanium dioxide （TiQ） on microcmstacean survival. Daphnia ruagna was used as a bioindicator for acute exposure test in suspensions from 0.0001 to 10,000 ppm. Cefiodaphnia dubia was used for chronic test in Ti02 suspensions from 0.001 to 100 ppm, D. magna populations presented high susceptibihty to all silver based additives, with 100% mortahty after 24 hr of exposure. A different result was found in the acute experiments containing TiO2 suspensions, with mortality rates only after 48 hr of incubation. Even on acute and chronic tests, Ti02 did not reach a hnear concentration-response uersus mortality, with 1 ppm being more toxic than 10,000 ppm on acute test and 0.001 more toxic than 0.01 ppm on chronic assay. Silver based material toxicity was attributed to silver itself, and had no relation to either form （nano or ion） or carrier （silica, phosphate glass or bentonite）. Ti02 demonstrated to have a low acute toxicity against D. magna.

关键词： Daphnia magnaCeriodaphnia dubiaTitanium dioxideSilver ionNanosilver

Risk factors, surgical complications and graft survival in liver transplant recipients with early allograft dysfunction

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Hepatobiliary & Pancreatic Diseases International 2019年第5期18卷 423-429页

作者： douglas Bastos-Neves Paolo Rogerio de Oliveira Salvalaggio Marcio Dias de Almeida Digestive and Hepatobiliary Surgery Hospital Sao Vicente de PauloRio de JaneiroBrazil Liver Transplant Unit Hospital Israelita Albert EinsteinSao PauloBrazil

Background: Early allograft dysfunction (EAD) is a severe complication after liver transplantation. The associated risk factors and complications have re-gained recent interest. This study investigated risk factors, survival and complications associated with EAD in a large liver transplant center in Latin America. Methods: Retrospective, unicenter, cohort, based on data from adult patients undergoing first deceaseddonor liver transplant from January 2009 to December 2013. EAD was defined by one or more of the following:(i) bilirubin ≥10 mg/dL on postoperative day 7;(ii) international normalized ratio ≥1.6 on postoperative day 7, and (iii) alanine aminotransferase or aspartate aminotransferase > 2000 IU/L within the first seven days after transplant. Results: A total of 602 patients were included;of these 34.2% developed EAD. Donor risk factors were male ( P = 0.007), age between 50 and 59 years ( P = 0.034), overweight ( P = 0.028) or grade I obesity ( P = 0.012), sodium > 157 mmol/L ( P = 0.002) and grade IV ischemia/reperfusion injury ( P = 0.002). Cold ischemia time ≥10 h ( P = 0.008) and warm ischemia time ≥40 min ( P = 0.013) were the surgical factors. Male ( P 157 mmol/L and grade Ⅳ ischemia/reperfusion injury. Cold ischemia time ≥10 h and warm ischemia time ≥40 min were the surgical risk factors. Male was the only recipient protective factor. Patients with EAD had higher reoperations and graft loss rates.

关键词： Graft survival Liver transplantation Primary graft dysfunction Donor evaluation

Identification of cancer stem cells provides novel tumor models for drug discovery

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Frontiers of Medicine 2012年第2期6卷 112-121页

作者： douglas D.Fang Danyi Wen Yajun Xu Shanghai ChemPartner Co. Ltd.998 Halei RoadZhangjiang Hi-Tech ParkPudong New DistrictShanghai 201203China

Cancer stem cells(CSCs)have received considerable attention from the research community since they were first reported in human acute myeloid leukemia 15 years *** evidence suggests that CSCs are responsible for tumor initiation and progression,drug resistance,and metastasis in both liquid and solid *** findings lead to the development of novel compounds targeting CSC populations that is becoming increasingly important for eradicating CSCs in heterogeneous tumor masses and to cure the *** 2003,we have participated in CSC studies and encountered crucial early events in the *** article reviews the history of CSC biology,clarifies the term and its definition,and further addresses the issue of how to utilize CSCs in therapeutic target discovery and drug development based on our substantial experience.

关键词： cancer stem cell tumor model drug discovery