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Gallium-Catalyzed Silicon Oxide Nanowire Growth

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Tsinghua Science and Technology 2005年第6期10卷 718-728页

作者： Zheng Wei Pan Sheng Dai douglas H. Lowndes Department of Materials Science and Engineering University of Tennessee Knoxville Tennessee 37996 USA Condensed Matter Sciences Division Oak Ridge National Laboratory Oak Ridge Tennessee 37830 USA Chemical Sciences Division Oak Ridge National Laboratory Oak Ridge Tennessee 37830 USA

Silicon oxide nanowires tend to assemble into various complex morphologies through a metalcatalyzed vapor-liquid-solid （VLS） growth process. This article summarizes our recent efforts in the controlled growth of silicon oxide nanowire assemblies by using molten gallium as the catalyst and silicon wafer, SiO powder, or silane （Sill4） as the silicon sources. Silicon oxide nanowire assemblies with morphologies of carrotlike, cometlike, gourdlike, spindlelike, badmintonlike, sandwichlike, etc. were obtained. Although the morphologies of the nanowire assemblies are temperatureand silicon source-dependent, they share similar structural and compositional features： all the assemblies contain a microscale spherical liquid Ga ball and a highly aligned, closely packed amorphous silicon oxide nanowire bunch. The Ga-catalyzed silicon oxide nanowire growth reveals several interesting new nanowire growth phenomena that expand our knowledge of the conventional VLS nanowire growth mechanism.

关键词： gallium silicon oxide nanowires vapor-liquid-solid (VLS) catalyst GaN powder Si wafer SiH4 gas SiO powder

High Performance Ring Oscillators from 10-nm Wide Silicon Nanowire Field-Effect Transistors

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Nano Research 2011年第10期4卷 1005-1012页

作者： Ruo-Gu Huang douglas Tham Dunwei Wang James R. Heath Department of Electrical Engineering Calilfomia Institute of Technology MC 136-93 Pasadena CA 91125 USA Division of Chemistry and Chemical Engineering California Institute of Technology MC 127-72 Pasadena CA 91125 USA Department of Chemistry Boston College 140 Commonwealth Ave Chestnut Hill Massachusetts 02467 USA

We explore 10-nm wide Si nanowire （SiNW） field-effect transistors （FETs） for logic applications, via the fabrication and testing of SiNW-based ring oscillators. We report on SiNW surface treatments and dielectric annealing, for producing SiNW FETs that exhibit high performance in terms of large on/off-state current ratio （-10s）, low drain-induced barrier lowering （-30 mV） and low subthreshold swing （-80 mV/decade）. The performance of inverter and ring-oscillator circuits fabricated from these nanowire FETs are also explored. The inverter demonstrates the highest voltage gain （-148） reported for a SiNW-based NOT gate, and the ring oscillator exhibits near rail-to-rail oscillation centered at 13.4 MHz. The static and dynamic characteristics of these NW devices indicate that these SiNW-based FET circuits are excellent candidates for various high-performance nanoelectronic applications.

关键词： Silicon nanowire (SiNW) field-effect transistor (FET) surface treatment inverter ring oscillator

Animal models of genetic causes of male infertility

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Asian Journal of Andrology 2002年第3期4卷 213-219页

作者： Greg L. Christensen douglas T. Carrell Andrology Department University of Utah School of Medicine Salt Lake City Utah 84132 USAAndrology Department University of Utah School of Medicine Salt Lake City Utah 84132 USA

Introduction In the past 10 years, more than 100 different genetically engineered mice have been developed with an abnormality in spermatogenesis. More than half of these male infertility animal models have been reported in the past three years alone. Spermatogenic defects in these models vary considerably, ranging from the inappropriate migration of primordial germ cells to the inability of mature spermatozoa to bind the zona pellucida. Many of

关键词： animal models genes genetics knockout male infertility

Enteral stents for the management of malignant colorectal obstruction

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World Journal of Gastroenterology 2014年第37期20卷 13239-13245页

作者： Jeremy Kaplan Anna Strongin douglas G Adler Ali A Siddiqui Division of Gastroenterology and Hepatology Department of Internal Medi-cineThomas Jefferson University Hospital Division of Gastroenterology and Hepatology Department of Internal MedicineUniversity of Utah

Colorectal cancer (CRC) is the 3rd most common cancer in the United States with more than 10000 new cases diagnosed annually. Approximately 20% of patients with CRC will have distant metastasis at time of diagnosis, making them poor candidates for primary surgical resection. Similarly, 8%-25% of patients with CRC will present with bowel obstruction and will require palliative therapy. Emergent surgical decompression has a high mortality and morbidity, and often leads to a colostomy which impairs the patient’s quality of life. In the last decade, there has been an increasing use of colonic stents for palliative therapy to relieve malignant colonic obstruction. Colonic stents have been shown to be effective and safe to treat obstruction from CRC, and are now the therapy of choice in this scenario. In the setting of an acute bowel obstruction in patients with potentially resectable colon cancer, stents may be used to delay surgery and thus allow for decompression, adequate bowel preparation, and optimization of the patient’s condition for curative surgical intervention. An overall complication rate (major and minor) of up to 25% has been associated with the procedure. Long term failure of stents may result from stent migration and tumor ingrowth. In the majority of cases, repeat stenting or surgical intervention can successfully overcome these adverse effects.

关键词： Colorectal cancer Colonic obstruction Self expanding metal stents Intestinal obstruction/etiology Intestinal obstruction/mortality Intestinal obstruction/surgery Survival rate

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