Single-Site Palladium(II) Catalyst for Oxidative Heck Reaction: Catalytic Performance and Kinetic Investigations

Energy Technology Data Exchange (ETDEWEB)

Duan, Hui; Li, Mengyang; Zhang, Guanghui; Gallagher, James R.; Huang, Zhiliang; Sun, Yu; Luo, Zhong; Chen, Hongzhong; Miller, Jeffrey T.; Zou, Ruqiang; Lei, Aiwen; Zhao, Yanli

2015-01-01

ABSTRACT: The development of organometallic single-site catalysts (SSCs) has inspired the designs of new heterogeneous catalysts with high efficiency. Nevertheless, the application of SSCs in certain modern organic reactions, such as C-C bond formation reactions, has still been less investigated. In this study, a single-site Pd(II) catalyst was developed, where 2,2'-bipyridine-grafted periodic mesoporous organosilica (PMO) was employed as the support of a Pd(II) complex. The overall performance of the single-site Pd(II) catalyst in the oxidative Heck reaction was then investigated. The investigation results show that the catalyst displays over 99% selectivity for the product formation with high reaction yield. Kinetic profiles further confirm its high catalytic efficiency, showing that the rate constant is nearly 40 times higher than that for the free Pd(II) salt. X-ray absorption spectroscopy reveals that the catalyst has remarkable lifetime and recyclability.

On-Site Chiropractic Care as an Employee Benefit: A Single-Location Case Study.

Science.gov (United States)

Minicozzi, Salvatore J; Russell, Brent S

2017-09-01

The purpose of this report is to describe the role of on-site chiropractic care in one corporate environment. A part-time chiropractic practice that provides services to a single company on site, 1 day per week, is described. Most care is oriented toward "wellness," is paid for by the employer, and is limited only by the chiropractor's few weekly hours of on-site availability. With approval from the company, the authors conducted an absenteeism analysis after obtaining ethics approval and consent from employee-patients who received care between 2012 and 2014. Comparisons of absenteeism rates of the sample were compared with lost worktime rates from the US Bureau of Labor Statistics' Labor Force Statistics. Of 40 current employees, 35 used chiropractic services; 17 employee-patients met the inclusion criteria. The lost worktime rates of those using chiropractic services (0.72%, 0.55%, and 0.67%, for 2012, 2013, and 2014, respectively) were lower than corresponding rates from Labor Force Statistics (1.5%, 1.2%, and 1.1%). Absenteeism for the employee-patients was lower than equivalent national figures in this sample of workers. Though these results may or may not be related to the chiropractic care, these findings prompt further investigation into this relationship.

Well-defined single-site monohydride silica-supported zirconium from azazirconacyclopropane

KAUST Repository

Hamzaoui, Bilel

2015-01-13

The silica-supported azazirconacyclopropane ≡SiOZr(HNMe2)(η2-NMeCH2)(NMe2) (1) leads exclusively under hydrogenolysis conditions (H2, 150°C) to the single-site monopodal monohydride silica-supported zirconium species ≡SiOZr(HNMe2)(NMe2)2H (2). Reactivity studies by contacting compound 2 with ethylene, hydrogen/ethylene, propene, or hydrogen/propene, at a temperature of 200°C revealed alkene hydrogenation.

Well-defined single-site monohydride silica-supported zirconium from azazirconacyclopropane

KAUST Repository

Hamzaoui, Bilel; El Eter, Mohamad; Abou-Hamad, Edy; Chen, Yin; Pelletier, Jeremie; Basset, Jean-Marie

2015-01-01

The silica-supported azazirconacyclopropane ≡SiOZr(HNMe2)(η2-NMeCH2)(NMe2) (1) leads exclusively under hydrogenolysis conditions (H2, 150°C) to the single-site monopodal monohydride silica-supported zirconium species ≡SiOZr(HNMe2)(NMe2)2H (2). Reactivity studies by contacting compound 2 with ethylene, hydrogen/ethylene, propene, or hydrogen/propene, at a temperature of 200°C revealed alkene hydrogenation.

Laparoendoscopic Single-Site Pyelolithotomy With Use of a Carter-Thomason Needle Grasper

OpenAIRE

Seo, Ill Young; Rim, Joung Sik

2013-01-01

Purpose To study the feasibility and safety of the procedure, we present our early experience with laparoendoscopic single-site (LESS) pyelolithotomy performed by use of a Carter-Thomason needle grasper. Materials and Methods Four patients underwent LESS pyelolithotomy for the removal of renal pelvic stones. The patients' mean age was 57.8 years, and their mean body mass index was 23.01. We used a homemade single-port device made with a surgical glove that was inserted into a 2.5-cm periumbil...

Site-controlled InGaN/GaN single-photon-emitting diode

Energy Technology Data Exchange (ETDEWEB)

Zhang, Lei; Deng, Hui, E-mail: dengh@umich.edu [Department of Physics, University of Michigan, 450 Church St., Ann Arbor, Michigan 48109 (United States); Teng, Chu-Hsiang; Ku, Pei-Cheng, E-mail: peicheng@umich.edu [Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Ave., Ann Arbor, Michigan 48109 (United States)

2016-04-11

We report single-photon emission from electrically driven site-controlled InGaN/GaN quantum dots. The device is fabricated from a planar light-emitting diode structure containing a single InGaN quantum well, using a top-down approach. The location, dimension, and height of each single-photon-emitting diode are controlled lithographically, providing great flexibility for chip-scale integration.

Single-site catalyst promoters accelerate metal-catalyzed nitroarene hydrogenation

KAUST Repository

Wang, Liang

2018-04-04

Atomically dispersed supported metal catalysts are drawing wide attention because of the opportunities they offer for new catalytic properties combined with efficient use of the metals. We extend this class of materials to catalysts that incorporate atomically dispersed metal atoms as promoters. The catalysts are used for the challenging nitroarene hydrogenation and found to have both high activity and selectivity. The promoters are single-site Sn on TiO2 supports that incorporate metal nanoparticle catalysts. Represented as M/Sn-TiO2 (M = Au, Ru, Pt, Ni), these catalysts decidedly outperform the unpromoted supported metals, even for hydrogenation of nitroarenes substituted with various reducible groups. The high activity and selectivity of these catalysts result from the creation of oxygen vacancies on the TiO2 surface by single-site Sn, which leads to efficient, selective activation of the nitro group coupled with a reaction involving hydrogen atoms activated on metal nanoparticles.

Single-site catalyst promoters accelerate metal-catalyzed nitroarene hydrogenation

KAUST Repository

Wang, Liang; Guan, Erjia; Zhang, Jian; Yang, Junhao; Zhu, Yihan; Han, Yu; Yang, Ming; Cen, Cheng; Fu, Gang; Gates, Bruce C.; Xiao, Feng-Shou

2018-01-01

Atomically dispersed supported metal catalysts are drawing wide attention because of the opportunities they offer for new catalytic properties combined with efficient use of the metals. We extend this class of materials to catalysts that incorporate atomically dispersed metal atoms as promoters. The catalysts are used for the challenging nitroarene hydrogenation and found to have both high activity and selectivity. The promoters are single-site Sn on TiO2 supports that incorporate metal nanoparticle catalysts. Represented as M/Sn-TiO2 (M = Au, Ru, Pt, Ni), these catalysts decidedly outperform the unpromoted supported metals, even for hydrogenation of nitroarenes substituted with various reducible groups. The high activity and selectivity of these catalysts result from the creation of oxygen vacancies on the TiO2 surface by single-site Sn, which leads to efficient, selective activation of the nitro group coupled with a reaction involving hydrogen atoms activated on metal nanoparticles.

Housing Retention in Single-Site Housing First for Chronically Homeless Individuals With Severe Alcohol Problems

Science.gov (United States)

Malone, Daniel K.; Clifasefi, Seema L.

2013-01-01

Objectives. We studied housing retention and its predictors in the single-site Housing First model. Methods. Participants (n = 111) were chronically homeless people with severe alcohol problems who lived in a single-site Housing First program and participated in a larger nonrandomized controlled trial (2005–2008) conducted in Seattle, Washington. At baseline, participants responded to self-report questionnaires assessing demographic, illness burden, alcohol and other drug use, and psychiatric variables. Housing status was recorded over 2 years. Results. Participants were interested in housing, although a sizable minority did not believe they would be able to maintain abstinence-based housing. Only 23% of participants returned to homelessness during the 2-year follow-up. Commonly cited risk factors—alcohol and other drug use, illness burden, psychiatric symptoms, and homelessness history—did not predict resumed homelessness. Active drinkers were more likely to stay in this housing project than nondrinkers. Conclusions. We found that single-site Housing First programming fills a gap in housing options for chronically homeless people with severe alcohol problems. PMID:24148063

Hanford tank initiative test facility site selection study

International Nuclear Information System (INIS)

Staehr, T.W.

1997-01-01

The Hanford Tanks Initiative (HTI) project is developing equipment for the removal of hard heel waste from the Hanford Site underground single-shell waste storage tanks. The HTI equipment will initially be installed in the 241-C-106 tank where its operation will be demonstrated. This study evaluates existing Hanford Site facilities and other sites for functional testing of the HTI equipment before it is installed into the 241-C-106 tank

Single-incision laparoscopic surgery through an ostomy site: a natural approach by an unnatural orifice.

Science.gov (United States)

Lopez, Nicole E; Peterson, Carrie Y; Ramamoorthy, Sonia L; McLemore, Elisabeth C; Sedrak, Michael F; Lowy, Andrew M; Horgan, Santiago; Talamini, Mark A; Sicklick, Jason K

2015-02-01

Single-incision laparoscopic surgery (SILS) is gaining popularity for a wide variety of surgical operations and capitalizes on the benefits of traditional laparoscopic surgery without incurring multiple incision sites. Traditionally, SILS is performed by a midline periumbilical approach. However, such a minimally invasive approach may be utilized in patients who already have an abdominal incision. Our series retrospectively reviews 7 cases in which we utilized the fascial defect at the time of after ostomy reversal as our SILS incision site. In turn, we performed a variety of concurrent intra-abdominal procedures with excellent technical success and outcomes. Our study is the largest single-institution case series of this novel approach and suggests that utilizing an existing ostomy-site abdominal incision is a safe and effective location for SILS port placement and should be considered in patients undergoing concurrent procedures.

Face, content, and construct validity of four, inanimate training exercises using the da Vinci ® Si surgical system configured with Single-Site ™ instrumentation.

Science.gov (United States)

Jarc, Anthony M; Curet, Myriam

2015-08-01

Validated training exercises are essential tools for surgeons as they develop technical skills to use robot-assisted minimally invasive surgical systems. The purpose of this study was to show face, content, and construct validity of four, inanimate training exercises using the da Vinci (®) Si surgical system configured with Single-Site (™) instrumentation. New (N = 21) and experienced (N = 6) surgeons participated in the study. New surgeons (11 Gynecology [GYN] and 10 General Surgery [GEN]) had not completed any da Vinci Single-Site cases but may have completed multiport cases using the da Vinci system. They participated in this study prior to attending a certification course focused on da Vinci Single-Site instrumentation. Experienced surgeons (5 GYN and 1 GEN) had completed at least 25 da Vinci Single-Site cases. The surgeons completed four inanimate training exercises and then rated them with a questionnaire. Raw metrics and overall normalized scores were computed using both video recordings and kinematic data collected from the surgical system. The experienced surgeons significantly outperformed new surgeons for many raw metrics and the overall normalized scores derived from video review (p da Vinci Single-Site surgery and actually testing the technical skills used during da Vinci Single-Site surgery. In summary, the four training exercises showed face, content, and construct validity. Improved overall scores could be developed using additional metrics not included in this study. The results suggest that the training exercises could be used in an overall training curriculum aimed at developing proficiency in technical skills for surgeons new to da Vinci Single-Site instrumentation.

Learning curve for laparoendoscopic single-site surgery for an experienced laparoscopic surgeon

OpenAIRE

Pao-Ling Torng; Kuan-Hung Lin; Jing-Shiang Hwang; Hui-Shan Liu; I-Hui Chen; Chi-Ling Chen; Su-Cheng Huang

2013-01-01

Objectives: To assess the learning curve and safety of laparoendoscopic single-site (LESS) surgery of gynecological surgeries. Materials and methods: Sixty-three women who underwent LESS surgery by a single experienced laparoscopic surgeon from February 2011 to August 2011 were included. Commercialized single-incision laparoscopic surgery homemade ports were used, along with conventional straight instruments. The learning curve has been defined as the additional surgical time with respect ...

Single site porphyrine-like structures advantages over metals for selective electrochemical CO2 reduction

DEFF Research Database (Denmark)

Bagger, Alexander; Ju, Wen; Varela, Ana Sofia

2017-01-01

Currently, no catalysts are completely selective for the electrochemical CO2 Reduction Reaction (CO2RR). Based on trends in density functional theory calculations of reaction intermediates we find that the single metal site in a porphyrine-like structure has a simple advantage of limiting...... the competing Hydrogen Evolution Reaction (HER). The single metal site in a porphyrine-like structure requires an ontop site binding of hydrogen, compared to the hollow site binding of hydrogen on a metal catalyst surface. The difference in binding site structure gives a fundamental energy-shift in the scaling...... relation of ∼0.3eV between the COOH* vs. H* intermediate (CO2RR vs. HER). As a result, porphyrine-like catalysts have the advantage over metal catalyst of suppressing HER and enhancing CO2RR selectivity....

Stabilization of bacterially expressed erythropoietin by single site-specific introduction of short branched PEG chains at naturally occurring glycosylation sites.

Science.gov (United States)

Hoffmann, E; Streichert, K; Nischan, N; Seitz, C; Brunner, T; Schwagerus, S; Hackenberger, C P R; Rubini, M

2016-05-24

The covalent attachment of polyethylene glycol (PEG) to therapeutic proteins can improve their physicochemical properties. In this work we utilized the non-natural amino acid p-azidophenylalanine (pAzF) in combination with the chemoselective Staudinger-phosphite reaction to install branched PEG chains to recombinant unglycosylated erythropoietin (EPO) at each single naturally occurring glycosylation site. PEGylation with two short 750 or 2000 Da PEG units at positions 24, 38, or 83 significantly decreased unspecific aggregation and proteolytic degradation while biological activity in vitro was preserved or even increased in comparison to full-glycosylated EPO. This site-specific bioconjugation approach permits to analyse the impact of PEGylation at single positions. These results represent an important step towards the engineering of site-specifically modified EPO variants from bacterial expression with increased therapeutic efficacy.

The effect of driving force on intramolecular electron transfer in proteins. Studies on single-site mutated azurins

DEFF Research Database (Denmark)

Farver, O; Skov, L K; van de Kamp, M

1992-01-01

-6972]. To further investigate the nature of this long-range electron transfer (LRET) proceeding within the protein matrix, we have now investigated it in two azurins where amino acids have been substituted by single-site mutation of the wild-type Pseudomonas aeruginosa azurin. In one mutated protein, a methionine...... the reorganization energy, lambda and electronic coupling factor, beta. The calculated values fit very well with a through-bond LRET mechanism....

Chemoselective single-site Earth-abundant metal catalysts at metal–organic framework nodes

Energy Technology Data Exchange (ETDEWEB)

Manna, Kuntal; Ji, Pengfei; Lin, Zekai; Greene, Francis X.; Urban, Ania; Thacker, Nathan C.; Lin, Wenbin (UC)

2016-08-30

Earth-abundant metal catalysts are critically needed for sustainable chemical synthesis. Here we report a simple, cheap and effective strategy of producing novel earth-abundant metal catalysts at metal–organic framework (MOF) nodes for broad-scope organic transformations. The straightforward metalation of MOF secondary building units (SBUs) with cobalt and iron salts affords highly active and reusable single-site solid catalysts for a range of organic reactions, including chemoselective borylation, silylation and amination of benzylic C–H bonds, as well as hydrogenation and hydroboration of alkenes and ketones. Our structural, spectroscopic and kinetic studies suggest that chemoselective organic transformations occur on site-isolated, electron-deficient and coordinatively unsaturated metal centres at the SBUs via σ-bond metathesis pathways and as a result of the steric environment around the catalytic site. MOFs thus provide a novel platform for the development of highly active and affordable base metal catalysts for the sustainable synthesis of fine chemicals.

EPR studies of gamma-irradiated taurine single crystals

International Nuclear Information System (INIS)

Bulut, A.; Karabulut, B.; Tapramaz, R.; Koeksal, F.

2000-01-01

An EPR study of gamma-irradiated taurine [C 2 H 7 NO 3 S] single crystal was carried out at room temperature. The EPR spectra were recorded in the three at mutually perpendicular planes. There are two magnetically distinct sites in monoclinic lattice. The principle values of g and hyperfine constants for both sites were calculated. The results have indicated the presence of 32 SO - 2 and 33 SO - 2 radicals. The hyperfine values of 33 SO - 2 radical were used to obtain O-S-O bond angle for both sites

Catalysis by Design: Well-Defined Single-Site Heterogeneous Catalysts

KAUST Repository

Pelletier, Jeremie

2016-03-09

ConspectusHeterogeneous catalysis, a field important industrially and scientifically, is increasingly seeking and refining strategies to render itself more predictable. The main issue is due to the nature and the population of catalytically active sites. Their number is generally low to very low, their "acid strengths" or " redox properties" are not homogeneous, and the material may display related yet inactive sites on the same material. In many heterogeneous catalysts, the discovery of a structure-activity reationship is at best challenging. One possible solution is to generate single-site catalysts in which most, if not all, of the sites are structurally identical. Within this context and using the right tools, the catalyst structure can be designed and well-defined, to reach a molecular understanding. It is then feasible to understand the structure-activity relationship and to develop predictable heterogeneous catalysis. Single-site well-defined heterogeneous catalysts can be prepared using concepts and tools of surface organometallic chemistry (SOMC). This approach operates by reacting organometallic compounds with surfaces of highly divided oxides (or of metal nanoparticles). This strategy has a solid track record to reveal structure-activity relationship to the extent that it is becoming now quite predictable. Almost all elements of the periodical table have been grafted on surfaces of oxides (from simple oxides such as silica or alumina to more sophisticated materials regarding composition or porosity).Considering catalytic hydrocarbon transformations, heterogeneous catalysis outcome may now be predicted based on existing mechanistic proposals and the rules of molecular chemistry (organometallic, organic) associated with some concepts of surface sciences. A thorough characterization of the grafted metal centers must be carried out using tools spanning from molecular organometallic or surface chemistry. By selection of the metal, its ligand set, and the

Functionalization of silicon-doped single walled carbon nanotubes at the doping site: An ab initio study

International Nuclear Information System (INIS)

Song Chen; Xia Yueyuan; Zhao Mingwen; Liu Xiangdong; Li Feng; Huang Boda; Zhang Hongyu; Zhang Bingyun

2006-01-01

We performed ab initio calculations on the cytosine-functionalized silicon-doped single walled carbon nanotubes (SWNT). The results show that silicon substitutional doping to SWNT can dramatically change the atomic and electronic structures of the SWNT. And more importantly, it may provide an efficient pathway for further sidewall functionalization to synthesize more complicated SWNT based complex materials, for example, our previously proposed base-functionalized SWNTs, because the doping silicon atom can improve the reaction activity of the tube at the doping site due to its preference to form sp3 hybridization bonding

Binding and Translocation of Termination Factor Rho Studied at the Single-Molecule Level

Science.gov (United States)

Koslover, Daniel J.; Fazal, Furqan M.; Mooney, Rachel A.; Landick, Robert; Block, Steven M.

2012-01-01

Rho termination factor is an essential hexameric helicase responsible for terminating 20–50% of all mRNA synthesis in E. coli. We used single- molecule force spectroscopy to investigate Rho-RNA binding interactions at the Rho- utilization (rut) site of the ? tR1 terminator. Our results are consistent with Rho complexes adopting two states, one that binds 57 ±2 nucleotides of RNA across all six of the Rho primary binding sites, and another that binds 85 ±2 nucleotides at the six primary sites plus a single secondary site situated at the center of the hexamer. The single-molecule data serve to establish that Rho translocates 5′-to-3′ towards RNA polymerase (RNAP) by a tethered-tracking mechanism, looping out the intervening RNA between the rut site and RNAP. These findings lead to a general model for Rho binding and translocation, and establish a novel experimental approach that should facilitate additional single- molecule studies of RNA-binding proteins. PMID:22885804

Laparoendoscopic single site surgery in urology: A single centre experience

Directory of Open Access Journals (Sweden)

Arvind P Ganpule

2012-01-01

Full Text Available Objective : To analyze our experience of 87 cases with single port surgery, which is also known as laparoendoscopic single site surgery (LESS. Materials and Methods: Case records of all LESS procedures performed between December 2007 and June 2010 were analysed. The procedures performed were donor nephrectomy (n=45, simple nephrectomy (n=27, radical nephrectomy (n=5, pyeloplasty (n=9, and ureteroneocystostomy (n=1. Parameters analysed were operating room (OR time, estimated blood loss (EBL, visual analogue score (VAS, and complications in all patients undergoing LESS procedure and additionally, warm ischaemia time (WIT and graft outcome in patients undergoing LESS donor nephrectomy. In reconstructive procedures, the functional assessment was performed with a diuretic renogram at 6 months. Results: In LESS donor nephrectomy, the mean WIT was 6.9 ± 1.9 min. Mean serum creatinine in recipients at 1 month was 0.96 ± 0.21 mg%. We encountered one instance each of renal artery injury, renal vein injury, large bowel injury, minor cortical laceration at the upper pole and two instances of diaphragmatic injury. In LESS simple nephrectomy, the average OR time was 148.7 ± 52.2 min and hospital stay was 3.7 ± 1.2 days. There was one instance of large bowel injury during specimen retrieval. In LESS radical nephrectomy, the average OR time was 202.5 ± 35.7 min and average hospital stay was 4.2 ± 1.3 days. 6 patients of LESS pyeloplasty completed follow up with a diuretic renogram showing a good drainage. LESS ureteroneocystostomy could also be performed successfully without any complications. Conclusion: LESS surgery can be accomplished safely in nephrectomy and reconstructive procedures such as pyeloplasty and ureteroneocystostomy with equivalent outcomes as standard laparoscopy and with added benefits of cosmesis and quicker convalescence. LESS donor nephrectomy is a technically feasible procedure; current status of procedure needs to be proved with

EPR studies of gamma-irradiated taurine single crystals

Energy Technology Data Exchange (ETDEWEB)

Bulut, A. E-mail: abulut@samsun.omu.edu.tr; Karabulut, B.; Tapramaz, R.; Koeksal, F

2000-04-01

An EPR study of gamma-irradiated taurine [C{sub 2}H{sub 7}NO{sub 3}S] single crystal was carried out at room temperature. The EPR spectra were recorded in the three at mutually perpendicular planes. There are two magnetically distinct sites in monoclinic lattice. The principle values of g and hyperfine constants for both sites were calculated. The results have indicated the presence of {sup 32}SO{sup -}{sub 2} and {sup 33}SO{sup -}{sub 2} radicals. The hyperfine values of {sup 33}SO{sup -}{sub 2} radical were used to obtain O-S-O bond angle for both sites.

Current status of natural orifice trans-endoscopic surgery (NOTES and laparoendoscopic single site surgery (LESS in urologic surgery

Directory of Open Access Journals (Sweden)

Rafael E. Sanchez-Salas

2010-08-01

Full Text Available Laparoendoscopic single site surgery (LESS and natural orifice transluminal endoscopic surgery (NOTES represent novel approaches in urological surgery. To perform a review of the literature in order describe the current status of LESS and NOTES in Urology. References for this manuscript were obtained by performing a review of the available literature in PubMed from 01-01-02 to 15-05-09. Search terms included single port, single site, NOTES, LESS and single incision. A total of 412 manuscripts were initially identified. Out of these, 64 manuscripts were selected based in their urological content. The manuscript features subheadings for experimental and clinical studies, as NOTES-LESS is a new surgical technique and its future evolution will probably rely in initial verified feasibility. A subheading for reviews presents information regarding common language and consensus for the techniques. The issue of complications published in clinical series and the future needs of NOTES-LESS, are also presented.

Individual single-site travel cost model for Czech paradise geopark

Directory of Open Access Journals (Sweden)

Jan Špaček

2013-01-01

Full Text Available Geotourism is a new phenomenon, which has emerged in the tourism literature during the past two decades, and whose meaning suffered from global census. Geotourism is still a new discipline and relatively little has been written about its demand side, demonstrated by a lack of studies in the literature This article studies the recreational value of geotourism areas, and focuses on the first geopark in the Czech Republic, namely the Czech Paradise Geopark. To assess the recreational value the travel cost method is applied, specifically the individual travel cost model. The necessary research data was gathered through intensive tourist surveys conducted in the study area. Data gathered in the respondents’ survey served to determine the consumer surplus as a measure of recreational value and to develop the single site travel cost model. The dependent variable in the conducted model is the number of visits in the area and among the independent variables, studied age, education, travel cost, family status, economic activity and income. The results were subsequently compared to findings in the available literature, research works and case studies.

Ab initio calculations of partial molar properties in the single-site approximation

DEFF Research Database (Denmark)

Ruban, Andrei; Skriver, Hans Lomholt

1997-01-01

We discuss the application of the single-site approximation in calculations of partial molar quantities, e.g., impurity solution energy, segregation energy, and effective chemical potential, which are related to a variation of the composition of an alloy or its nonequivalent parts. We demonstrate...

Single-Site Tetracoordinated Aluminum Hydride Supported on Mesoporous Silica. From Dream to Reality!

KAUST Repository

Werghi, Baraa; Bendjeriou-Sedjerari, Anissa; Jedidi, Abdesslem; Abou-Hamad, Edy; Cavallo, Luigi; Basset, Jean-Marie

2016-01-01

The reaction of mesoporous silica (SBA15) dehydroxylated at 700 °C with diisobutylaluminum hydride, i-Bu2AlH, gives after thermal treatment a single-site tetrahedral aluminum hydride with high selectivity. The starting aluminum isobutyl and the final aluminum hydride have been fully characterized by FT-IR, advanced SS NMR spectroscopy (1H, 13C, multiple quanta (MQ) 2D 1H-1H, and 27Al), and elemental analysis, while DFT calculations provide a rationalization of the occurring reactivity. Trimeric i-Bu2AlH reacts selectively with surface silanols without affecting the siloxane bridges. Its analogous hydride catalyzes ethylene polymerization. Indeed, catalytic tests show that this single aluminum hydride site is active in the production of a high-density polyethylene (HDPE). © 2016 American Chemical Society.

Single-Site Tetracoordinated Aluminum Hydride Supported on Mesoporous Silica. From Dream to Reality!

KAUST Repository

Werghi, Baraa

2016-09-26

The reaction of mesoporous silica (SBA15) dehydroxylated at 700 °C with diisobutylaluminum hydride, i-Bu2AlH, gives after thermal treatment a single-site tetrahedral aluminum hydride with high selectivity. The starting aluminum isobutyl and the final aluminum hydride have been fully characterized by FT-IR, advanced SS NMR spectroscopy (1H, 13C, multiple quanta (MQ) 2D 1H-1H, and 27Al), and elemental analysis, while DFT calculations provide a rationalization of the occurring reactivity. Trimeric i-Bu2AlH reacts selectively with surface silanols without affecting the siloxane bridges. Its analogous hydride catalyzes ethylene polymerization. Indeed, catalytic tests show that this single aluminum hydride site is active in the production of a high-density polyethylene (HDPE). © 2016 American Chemical Society.

Ligand-tailored single-site silica supported titanium catalysts: Synthesis, characterization and towards cyanosilylation reaction

International Nuclear Information System (INIS)

Xu, Wei; Li, Yani; Yu, Bo; Yang, Jindou; Zhang, Ying; Chen, Xi; Zhang, Guofang; Gao, Ziwei

2015-01-01

A successive anchoring of Ti(NMe 2 ) 4 , cyclopentadiene and a O-donor ligand, 1-hydroxyethylbenzene (PEA), 1,1′-bi-2-naphthol (Binol) or 2,3-dihydroxybutanedioic acid diethyl ester (Tartrate), on silica was conducted by SOMC strategy in moderate conditions. The silica, monitored by in-situ Fourier transform infrared spectroscopy (in-situ FT-IR), was pretreated at different temperatures (200, 500 and 800 °C). The ligand tailored silica-supported titanium complexes were characterized by in-situ FT-IR, 13 C CP MAS-NMR, X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure (XANES) and elemental analysis in detail, verifying that the surface titanium species are single sited. The catalytic activity of the ligand tailored single-site silica supported titanium complexes was evaluated by a cyanosilylation of benzaldehyde. The results showed that the catalytic activity is dependent strongly on the dehydroxylation temperatures of silica and the configuration of the ligands. - Graphical abstract: The ligand-tailored silica supported “single site” titanium complexes were synthesized by SOMC strategy and fully characterized. Their catalytic activity were evaluated by benzaldehyde silylcyanation. - Highlights: • Single-site silica supported Ti active species was prepared by SOMC technique. • O-donor ligand tailored Ti surface species was synthesized. • The surface species was characterized by XPS, 13 C CP-MAS NMR, XANES etc. • Catalytic activity of the Ti active species in silylcyanation reaction was evaluated

Ligand-tailored single-site silica supported titanium catalysts: Synthesis, characterization and towards cyanosilylation reaction

Energy Technology Data Exchange (ETDEWEB)

Xu, Wei; Li, Yani; Yu, Bo; Yang, Jindou; Zhang, Ying; Chen, Xi; Zhang, Guofang, E-mail: gfzhang@snnu.edu.cn; Gao, Ziwei, E-mail: zwgao@snnu.edu.cn

2015-01-15

A successive anchoring of Ti(NMe{sub 2}){sub 4}, cyclopentadiene and a O-donor ligand, 1-hydroxyethylbenzene (PEA), 1,1′-bi-2-naphthol (Binol) or 2,3-dihydroxybutanedioic acid diethyl ester (Tartrate), on silica was conducted by SOMC strategy in moderate conditions. The silica, monitored by in-situ Fourier transform infrared spectroscopy (in-situ FT-IR), was pretreated at different temperatures (200, 500 and 800 °C). The ligand tailored silica-supported titanium complexes were characterized by in-situ FT-IR, {sup 13}C CP MAS-NMR, X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure (XANES) and elemental analysis in detail, verifying that the surface titanium species are single sited. The catalytic activity of the ligand tailored single-site silica supported titanium complexes was evaluated by a cyanosilylation of benzaldehyde. The results showed that the catalytic activity is dependent strongly on the dehydroxylation temperatures of silica and the configuration of the ligands. - Graphical abstract: The ligand-tailored silica supported “single site” titanium complexes were synthesized by SOMC strategy and fully characterized. Their catalytic activity were evaluated by benzaldehyde silylcyanation. - Highlights: • Single-site silica supported Ti active species was prepared by SOMC technique. • O-donor ligand tailored Ti surface species was synthesized. • The surface species was characterized by XPS, {sup 13}C CP-MAS NMR, XANES etc. • Catalytic activity of the Ti active species in silylcyanation reaction was evaluated.

Real-Time Visualization of Active Species in a Single-Site Metal–Organic Framework Photocatalyst

Energy Technology Data Exchange (ETDEWEB)

Yang, Sizhuo [Department of Chemistry, Marquette University, Milwaukee, Wisconsin 53201, United States; Pattengale, Brian [Department of Chemistry, Marquette University, Milwaukee, Wisconsin 53201, United States; Lee, Sungsik [X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60349, United States; Huang, Jier [Department of Chemistry, Marquette University, Milwaukee, Wisconsin 53201, United States

2018-02-06

In this work, we report a new single-site photocatalyst (Co-Ru-UIO- 67(bpy)) based on a metal-organic framework platform with incorporated molecular photosensitizer and catalyst. We show that this catalyst not only demonstrates exceptional activity for light-driven H2 production but also can be recycled without loss of activity. Using the combination of optical transient absorption spectroscopy and in situ X-ray absorption spectroscopy, we not only captured the key CoI intermediate species formed after ultrafast charge transfer from the incorporated photosensitizer but also identified the rate-limiting step in the catalytic cycle, providing insight into the catalysis mechanism of these single-site metal-organic framework photocatalysts.

Therapeutic benefits of carbon dioxide (CO2) laser on single-site HPV lesions in the lower female genital tract

Science.gov (United States)

Urru, Giovanni; Moretti, Gianfranco

1998-01-01

Numerous studies have shown contradictory variable percentages of recurrent HPV lesions, after various therapies. The present study therefore evaluates the effectiveness of CO2 laser vaporization in the treatment of single-site HPV lesions of the lower female genital tract in order to confirm the conviction that physical therapy alone, in agreement with some findings reported in the literature, is capable of guaranteeing a high cure rate in selected patients. From January 1995 to June 1996, seventy- five female patients were treated with CO2 laser vaporization for single-site genital HPV lesions, some of which were associated with low-grade intra-epithelial neoplasia. The success rate after 12 months proved to be 97%. The pre-existing clinical symptoms disappeared in all the patients treated. No complication in the vaporization procedure was encountered.

Synthesis of a molecularly defined single-active site heterogeneous catalyst for selective oxidation of N-heterocycles.

Science.gov (United States)

Zhang, Yujing; Pang, Shaofeng; Wei, Zhihong; Jiao, Haijun; Dai, Xingchao; Wang, Hongli; Shi, Feng

2018-04-13

Generally, a homogeneous catalyst exhibits good activity and defined active sites but it is difficult to recycle. Meanwhile, a heterogeneous catalyst can easily be reused but its active site is difficult to reveal. It is interesting to bridge the gap between homogeneous and heterogeneous catalysis via controllable construction of a heterogeneous catalyst containing defined active sites. Here, we report that a molecularly defined, single-active site heterogeneous catalyst has been designed and prepared via the oxidative polymerization of maleimide derivatives. These polymaleimide derivatives can be active catalysts for the selective oxidation of heterocyclic compounds to quinoline and indole via the recycling of -C=O and -C-OH groups, which was confirmed by tracing the reaction with GC-MS using maleimide as the catalyst and by FT-IR analysis with polymaleimide as the catalyst. These results might promote the development of heterogeneous catalysts with molecularly defined single active sites exhibiting a comparable activity to homogeneous catalysts.

Screened Coulomb interactions in metallic alloys. II. Screening beyond the single-site and atomic-sphere approximations

DEFF Research Database (Denmark)

Ruban, Andrei; Simak, S.I.; Korzhavyi, P.A.

2002-01-01

-electron potential and energy. In the case of a random alloy such interactions can be accounted for only by lifting the atomic-sphere and single-site approximations, in order to include the polarization due to local environment effects. Nevertheless, a simple parametrization of the screened Coulomb interactions...... for the ordinary single-site methods, including the generalized perturbation method, is still possible. We obtained such a parametrization for bulk and surface NiPt alloys, which allows one to obtain quantitatively accurate effective interactions in this system....

Characterization of the corrosion behavior of the carbon steel liner in Hanford Site single-shell tanks

International Nuclear Information System (INIS)

Anantatmula, R.P.; Schwenk, E.B.; Danielson, M.J.

1994-06-01

Six safety initiatives have been identified for accelerating the resolution of waste tank safety issues and closure of unreviewed safety questions. Safety Initiative 5 is to reduce safety and environmental risk from tank leaks. Item d of Safety Initiative 5 is to complete corrosion studies of single-shell tanks to determine failure mechanisms and corrosion control options to minimize further degradation by June 1994. This report has been prepared to fulfill Safety Initiative 5, Item d. The corrosion mechanisms that apply to Hanford Site single-shell tanks are stress corrosion cracking, pitting/crevice corrosion, uniform corrosion, hydrogen embrittlement, and microbiologically influenced corrosion. The corrosion data relevant to the single-shell tanks dates back three decades, when results were obtained from in-situ corrosion coupons in a few single-shell tanks. Since that time there have been intertank transfers, evaporation, and chemical alterations of the waste. These activities have changed the character and the present composition of the waste is not well characterized. All conclusions and recommendations are made in the absence of relevant laboratory experimental data and tank inspection data. The report attempts to identify the failure mechanisms by a literature survey of carbon steel data in environments similar to the single-shell tank wastes, and by a review of the work performed at the Savannah River Site where similar wastes are stored in similar carbon steel tanks. Based on these surveys, and in the absence of data specific to Hanford single-shell tanks, it may be concluded that the single-shell tanks identified as leakers failed primarily by stress corrosion cracking due to the presence of high nitrate/low hydroxide wastes and residual stresses. In addition, some failures may be attributed to pitting under crevices in low hydroxide locations

A mathematical model of single target site location by Brownian movement in subcellular compartments.

Science.gov (United States)

Kuthan, Hartmut

2003-03-07

The location of distinct sites is mandatory for many cellular processes. In the subcompartments of the cell nucleus, only very small numbers of diffusing macromolecules and specific target sites of some types may be present. In this case, we are faced with the Brownian movement of individual macromolecules and their "random search" for single/few specific target sites, rather than bulk-averaged diffusion and multiple sites. In this article, I consider the location of a distant central target site, e.g. a globular protein, by individual macromolecules executing unbiased (i.e. drift-free) random walks in a spherical compartment. For this walk-and-capture model, the closed-form analytic solution of the first passage time probability density function (p.d.f.) has been obtained as well as the first and second moment. In the limit of a large ratio of the radii of the spherical diffusion space and central target, well-known relations for the variance and the first two moments for the exponential p.d.f. were found to hold with high accuracy. These calculations reinforce earlier numerical results and Monte Carlo simulations. A major implication derivable from the model is that non-directed random movement is an effective means for locating single sites in submicron-sized compartments, even when the diffusion coefficients are comparatively small and the diffusing species are present in one copy only. These theoretical conclusions are underscored numerically for effective diffusion constants ranging from 0.5 to 10.0 microm(2) s(-1), which have been reported for a couple of nuclear proteins in their physiological environment. Spherical compartments of submicron size are, for example, the Cajal bodies (size: 0.1-1.0 microm), which are present in 1-5 copies in the cell nucleus. Within a small Cajal body of radius 0.1 microm a single diffusing protein molecule (with D=0.5 microm(2) s(-1)) would encounter a medium-sized protein of radius 2.5 nm within 1 s with a probability near

Sites of termination of in vitro DNA synthesis on psoralen phototreated single-stranded templates

International Nuclear Information System (INIS)

Piette, J.; Hearst, J.

1985-01-01

Single-stranded DNA has been photochemically induced to react with 4'-hydroxymethyl-4,5',8-trimethylpsoralen (HMT) and used as substrate for DNA replication with E. coli DNA polymerase I large fragment. By using the dideoxy sequencing procedure, it is possible to map the termination sites on the template photoreacted with HMT. These sites occur at the nucleotides preceding each thymine residue (and a few cytosine residues), emphasizing the fact that in a single-stranded stretch of DNA, HMT reacts with each thymine residue without any specificity regarding the flanking base sequence of the thymine residues. In addition, termination of DNA synthesis due to psoralen-adducted thymine is not influenced by the efficiency of the 3'-5' exonuclease proof-reading activity of the DNA polymerase. (author)

Laparoendoscopic single site (LESS) cholecystectomy.

Science.gov (United States)

Hodgett, Steven E; Hernandez, Jonathan M; Morton, Connor A; Ross, Sharona B; Albrink, Michael; Rosemurgy, Alexander S

2009-02-01

The journey from conventional "open" operations to truly "minimally invasive" operations naturally includes progression from operations involving multiple trocars and multiple incisions to operations involving access through the umbilicus alone. Laparoscopic operations through the umbilicus alone, laparoendoscopic single site surgery (LESS), offer improved cosmesis and hopes for less pain and improved recovery. This study was undertaken to evaluate our initial experience with LESS cholecystectomy and to compare our initial experience to concurrent outcomes with more conventional multiport, multi-incision laparoscopic cholecystectomy. All patients referred for cholecystectomy over a 6-month period were offered LESS. Outcomes, including blood loss, operative time, complications, and length of stay were recorded. Outcomes with our first LESS cholecystectomies were compared to an uncontrolled group of concurrent patients undergoing multiport, multi-incision laparoscopic cholecystectomy at the same hospital by the same surgeon. Twenty-nine patients of median age 50 years undergoing LESS cholecystectomy from November 2007 until May 2008 were compared to 29* patients, median age 48 years, undergoing standard multiport, multiple-incision laparoscopic cholecystectomy over the same time period. Median operative time for patients undergoing LESS cholecystectomy was 72 min and was not different from that of patients undergoing multiport, multi-incision laparoscopic cholecystectomy (p = 0.81). Median length of hospital stay was 1.0 day for patients undergoing LESS cholecystectomy and was not different from patients undergoing standard laparoscopic cholecystectomy (p = 0.46). Operative estimated blood loss was less than 100 cc for all patients. No patients undergoing attempted LESS cholecystectomy had conversions to "open" operations; two patients had an additional trocar(s) placed distant from the umbilicus to aid in exposure. Three patients undergoing LESS cholecystectomy had

Density functional study the interaction of oxygen molecule with defect sites of graphene

Energy Technology Data Exchange (ETDEWEB)

Qi Xuejun [State Key Laboratory of Coal Combustion, Wuhan 430074 (China); Guo Xin, E-mail: guoxin@mail.hust.edu.cn [State Key Laboratory of Coal Combustion, Wuhan 430074 (China); Zheng Chuguang [State Key Laboratory of Coal Combustion, Wuhan 430074 (China)

2012-10-15

Highlights: Black-Right-Pointing-Pointer The defect sites existed on the graphite surface create active sites and enhance the reactivity of carbonaceous material. Black-Right-Pointing-Pointer Oxygen molecule more favor chemisorbed on the graphene surface contains defect sites than the perfect surface. Black-Right-Pointing-Pointer The single active oxygen atom adsorbed on the defect surfaces, it completely insert into the surface. - Abstract: The present article reports a theoretical study of oxygen interacted with graphene surface containing defect sites on the atomic level by employing the density functional theory combined with the graphene cluster model. It was founded that oxygen molecule prefers to be chemisorbed on the graphene surface containing defect sites compared to the perfect surface. The adsorption energy of O{sub 2} on the double defect site is about 2.5 times as large as that on the perfect graphene surface. Moreover, the oxygen molecule interacts with S-W defect site gives rise to stable epoxy structure, which pulling the carbon atom outward from the original site in the direction perpendicular to the surface. If the oxygen molecule is adsorbed on the single vacancy site, two C-O bonds are formed on the graphene surface. However, when the oxygen molecule is chemisorbed on the double vacancy site, the oxygen atoms substitute the missing carbon atom's position in the carbon plane and form a hexagonal structure on the graphene network. The results indicate that single active oxygen atom approaches the defect site, it's completely adsorbed in the plane and high energy is released. In all cases, the interaction of an oxygen atom with defect surface involves an exothermic process. The defect site creates active sites on the surface of graphene and produces catalytic effects during the process of oxidation of carbonaceous materials.

Laparoendoscopic single-site Heller myotomy with anterior fundoplication for achalasia.

Science.gov (United States)

Barry, Linda; Ross, Sharona; Dahal, Sujat; Morton, Connor; Okpaleke, Chinyere; Rosas, Melissa; Rosemurgy, Alexander S

2011-06-01

Laparoendoscopic single-site (LESS) surgery is beginning to include advanced laparoscopic operations such as Heller myotomy with anterior fundoplication. However, the efficacy of LESS Heller myotomy has not been established. This study aimed to evaluate the authors' initial experience with LESS Heller myotomy for achalasia. Transumbilical LESS Heller myotomy with concomitant anterior fundoplication for achalasia was undertaken for 66 patients after October 2007. Outcomes including operative time, complications, and length of hospital stay were recorded and compared with those for an earlier contiguous group of 66 consecutive patients undergoing conventional multi-incision laparoscopic Heller myotomy with anterior fundoplication. Symptoms before and after myotomy were scored by the patients using a Likert scale ranging from 0 (never/not severe) to 10 (always/very severe). Data were analyzed using the Mann-Whitney U test, the Wilcoxon matched-pairs test, and Fisher's exact test where appropriate. Patients undergoing LESS Heller myotomy were similar to those undergoing conventional laparoscopic Heller myotomy in gender, age, body mass index (BMI), blood loss, and length of hospital stay. However, the patients undergoing LESS Heller myotomies had operations of significantly longer duration (median, 117 vs. 93 min with the conventional laparoscopic approach) (pHeller myotomy, additional ports/incisions were required. No patients were converted to "open" operations, and no patients had procedure-specific complications. Symptom reduction was dramatic and satisfying after both LESS and conventional laparoscopic myotomy with fundoplication. The symptom reduction was similar with the two procedures. The LESS approach left no apparent umbilical scar. Heller myotomy with anterior fundoplication effectively treats achalasia. The findings showed LESS Heller myotomy with anterior fundoplication to be feasible, safe, and efficacious. Although the LESS approach increases operative

Real-time single-molecule tethered particle motion experiments reveal the kinetics and mechanisms of Cre-mediated site-specific recombination

Science.gov (United States)

Fan, Hsiu-Fang

2012-01-01

Tyrosine family recombinases (YRs) are widely utilized in genome engineering systems because they can easily direct DNA rearrangement. Cre recombinases, one of the most commonly used types of YRs, catalyze site-specific recombination between two loxP sites without the need for high-energy cofactors, other accessory proteins or a specific DNA target sequence between the loxP sites. Previous structural, analytical ultracentrifuge and electrophoretic analyses have provided details of the reaction kinetics and mechanisms of Cre recombinase activity; whether there are reaction intermediates or side pathways involved has been left unaddressed. Using tethered particle motion (TPM), the Cre-mediated site-specific recombination process has been delineated, from beginning to end, at the single-molecule level, including the formation of abortive complexes and wayward complexes blocking inactive nucleoprotein complexes from entering the recombination process. Reversibility in the strand-cleavage/-ligation process and the formation of a thermally stable Holliday junction intermediate were observed within the Cre-mediated site-specific recombination process. Rate constants for each elementary step, which explain the overall reaction outcomes under various conditions, were determined. Taking the findings of this study together, they demonstrate the potential of single-molecule methodology as an alternative approach for exploring reaction mechanisms in detail. PMID:22467208

Single-stranded γPNAs for in vivo site-specific genome editing via Watson-Crick recognition.

Science.gov (United States)

Bahal, Raman; Quijano, Elias; McNeer, Nicole A; Liu, Yanfeng; Bhunia, Dinesh C; Lopez-Giraldez, Francesco; Fields, Rachel J; Saltzman, William M; Ly, Danith H; Glazer, Peter M

2014-01-01

Triplex-forming peptide nucleic acids (PNAs) facilitate gene editing by stimulating recombination of donor DNAs within genomic DNA via site-specific formation of altered helical structures that further stimulate DNA repair. However, PNAs designed for triplex formation are sequence restricted to homopurine sites. Herein we describe a novel strategy where next generation single-stranded gamma PNAs (γPNAs) containing miniPEG substitutions at the gamma position can target genomic DNA in mouse bone marrow at mixed-sequence sites to induce targeted gene editing. In addition to enhanced binding, γPNAs confer increased solubility and improved formulation into poly(lactic-co-glycolic acid) (PLGA) nanoparticles for efficient intracellular delivery. Single-stranded γPNAs induce targeted gene editing at frequencies of 0.8% in mouse bone marrow cells treated ex vivo and 0.1% in vivo via IV injection, without detectable toxicity. These results suggest that γPNAs may provide a new tool for induced gene editing based on Watson-Crick recognition without sequence restriction.

Laparoendoscopic single site cholecystectomy: the first 100 patients.

Science.gov (United States)

Hernandez, Jonathan M; Morton, Connor A; Ross, Sharona; Albrink, Michael; Rosemurgy, Alexander S

2009-08-01

Laparoendoscopic single site (LESS) surgery promises improved cosmesis and possibly less pain. However, given the small series reported to date, true estimates of the advantages and possible disadvantages of LESS surgery remain unknown. This study was undertaken to evaluate the first 100 patients undergoing LESS cholecystectomy at our institution. Patients referred for cholecystectomy since November 2007 were considered for LESS cholecystectomy. Outcomes, including blood loss, operative time, complications, and length of stay, were recorded. Outcomes are compared with an uncontrolled concurrent group of patients undergoing multi-incision laparoscopic (i.e., conventional) cholecystectomy. One hundred patients with a median age of 44 years underwent LESS cholecystectomy; 30 patients with a median age of 46 years underwent conventional cholecystectomy over the same time period. Median operative time (70 vs 66 minutes, P = 0.67, Mann-Whitney) and hospital length of stay (1 vs 1 day, P = 0.81, Mann-Whitney) were not different for patients undergoing LESS or multi-incision cholecystectomies, respectively. Five patients undergoing LESS cholecystectomy had postoperative complications: cystic duct stump leak (one), pain control issues (three), and urinary retention (one). LESS cholecystectomy is a safe and effective alternative to conventional cholecystectomy. It can be undertaken without added operative time and provides patients with minimal, if any, scarring.

Single Policy Study

DEFF Research Database (Denmark)

Kronsell, Annica; Manners, Ian James

2015-01-01

Single policy studies are the most common form of European Union (EU) research. Single policy studies are widely used to understand the role of the EU in a wide variety of sectors, together with their development over time, and often offer public policy prescriptions. This chapter discusses...... the relevance of single policy studies in EU research and give examples of how such research can be designed and carried out. The chapter reviews three examples of single policy studies using different methods based on EU environmental policy, the EU biofuels directive, and the EU Common Security and Defence...... Policy (CSDP). The examples are illustrative of how single policy studies can be designed to use different approaches in the analysis: multiple streams approach to policy-making; a comparative hypothesis testing; and feminist institutional theory....

Useful Bicistronic Reporter System for Studying Poly(A Site-Defining cis Elements and Regulation of Alternative Polyadenylation

Directory of Open Access Journals (Sweden)

Zhongyuan Deng

2018-01-01

Full Text Available The link between polyadenylation (pA and various biological, behavioral, and pathological events of eukaryotes underlines the need to develop in vivo polyadenylation assay methods for characterization of the cis-acting elements, trans-acting factors and environmental stimuli that affect polyadenylation efficiency and/or relative usage of two alternative polyadenylation (APA sites. The current protein-based CAT or luciferase reporter systems can measure the polyadenylation efficiency of a single pA site or candidate cis element but not the choice of two APA sites. To address this issue, we developed a set of four new bicistronic reporter vectors that harbor either two luciferase or fluorescence protein open reading frames connected with one Internal Ribosome Entry Site (IRES. Transfection of single or dual insertion constructs of these vectors into mammalian cells demonstrated that they could be utilized not only to quantify the strength of a single candidate pA site or cis element, but also to accurately measure the relative usage of two APA sites at both the mRNA (qRT-PCR and protein levels. This represents the first reporter system that can study polyadenylation efficiency of a single pA site or element and regulation of two APA sites at both the mRNA and protein levels.

[Clinical retrospective control study of single-port laparoendoscopic and multi-port laparoscopic ovarian cystectomy].

Science.gov (United States)

Liu, X; Wen, M K; Liu, H Y; Sun, D W; Lang, J H; Fan, Q B; Shi, H H

2017-10-25

Objective: To investigate clinical outcomes of laparoendoscopic single-site ovarian cystectomy compared with traditional multi-port laparoscopic ovarian cystectomy. Methods: Data of 81 patients with ovarian cystectomy from January 2016 to May 2017, the single-site group ( n= 40) and the multi-port group ( n= 41) in Peking Union Medical College Hospital were retrospectively collected. The outcomes of single-site and multi-port groups were analyzed and compared, including: postoperative fever, operation time, blood loss, hemoglobin change, surgical complications, postoperative pain score, postoperative analgesic requirements, body image scale and cosmetic score, length of hospital stay, postoperative total cost. Results: No complication was found in two groups. No difference was found in postoperative fever, blood loss, hemoglobin change, postoperative pain score, length of hospital stay, and total cost between the two groups (all P> 0.05). Operation time was (50±20) minutes in single-site group, and (40±15) minutes in multi-port group; postoperative analgesic requirements was 28%(11/40) in single-site group, and 7%(4/41) in multi-port group; cosmetic score was 22.6±2.6 in single-site group, and 17.3±2.6 in multi-port group; body image scale was 5.7±1.2 in single-site group, and 6.2±1.2 in multi-port group; these four clinical parameters were statistical differences (all P< 0.05). Conculsion: Laparoendoscopic single-site ovarian cystectomy is feasible and safe, although it could't relieve the postoperative pian, it do offer a higher cosmetic satisfaction.

Site-selective substitutional doping with atomic precision on stepped Al (111) surface by single-atom manipulation.

Science.gov (United States)

Chen, Chang; Zhang, Jinhu; Dong, Guofeng; Shao, Hezhu; Ning, Bo-Yuan; Zhao, Li; Ning, Xi-Jing; Zhuang, Jun

2014-01-01

In fabrication of nano- and quantum devices, it is sometimes critical to position individual dopants at certain sites precisely to obtain the specific or enhanced functionalities. With first-principles simulations, we propose a method for substitutional doping of individual atom at a certain position on a stepped metal surface by single-atom manipulation. A selected atom at the step of Al (111) surface could be extracted vertically with an Al trimer-apex tip, and then the dopant atom will be positioned to this site. The details of the entire process including potential energy curves are given, which suggests the reliability of the proposed single-atom doping method.

Minimally invasive single-site surgery for the digestive system: A technological review

Directory of Open Access Journals (Sweden)

Dhumane Parag

2011-01-01

Full Text Available Minimally Invasive Single Site (MISS surgery is a better terminology to explain the novel concept of scarless surgery, which is increasingly making its way into clinical practice. But, there are some difficulties. We review the existing technologies for MISS surgery with regards to single-port devices, endoscope and camera, instruments, retractors and also the future perspectives for the evolution of MISS surgery. While we need to move ahead cautiously and wait for the development of appropriate technology, we believe that the "Ultimate form of Minimally Invasive Surgery" will be a hybrid form of MISS surgery and Natural Orifice Transluminal Endoscopic Surgery, complimented by technological innovations from the fields of robotics and computer-assisted surgery.

Robot-Assisted Laparoendoscopic Single-Site Partial Nephrectomy With the Novel Da Vinci Single-Site Platform: Initial Experience

Science.gov (United States)

Komninos, Christos; Tuliao, Patrick; Kim, Dae Keun; Choi, Young Deuk; Chung, Byung Ha

2014-01-01

Purpose To report our initial clinical cases of robotic laparoendoscopic single-site (R-LESS) partial nephrectomy (PN) performed with the use of the novel Da Vinci R-LESS platform. Materials and Methods Three patients underwent R-LESS PN from November 2013 through February 2014. Perioperative and postoperative outcomes were collected and intraoperative difficulties were noted. Results Operative time and estimated blood loss volume ranged between 100 and 110 minutes and between 50 and 500 mL, respectively. None of the patients was transfused. All cases were completed with the off-clamp technique, whereas one case required conversion to the conventional (multiport) approach because of difficulty in creating the appropriate scope for safe tumor resection. No major postoperative complications occurred, and all tumors were resected in safe margins. Length of hospital stay ranged between 3 and 7 days. The lack of EndoWrist movements, the external collisions, and the bed assistant's limited working space were noticed to be the main drawbacks of this surgical method. Conclusions Our initial experience with R-LESS PN with the novel Da Vinci platform shows that even though the procedure is feasible, it should be applied in only appropriately selected patients. However, further improvement is needed to overcome the existing limitations. PMID:24955221

Methodology of site studies

International Nuclear Information System (INIS)

Caries, J.C.; Hugon, J.; Grauby, A.

1980-01-01

This methodology consists in an essentially dynamic, estimated and follow-up analysis of the impact of discharges on all the environment compartments, whether natural or not, that play a part in the protection of man and his environment. It applies at two levels, to wit: the choice of site, or the detailed study of the site selected. Two examples of its application will be developed, namely: at the choice of site level in the case of marine sites, and of the detailed study level of the chosen site in that of a riverside site [fr

Hybrid Nanomaterials with Single-Site Catalysts by Spatially Controllable Immobilization of Nickel Complexes via Photoclick Chemistry for Alkene Epoxidation.

Science.gov (United States)

Ghosh, Dwaipayan; Febriansyah, Benny; Gupta, Disha; Ng, Leonard Kia-Sheun; Xi, Shibo; Du, Yonghua; Baikie, Tom; Dong, ZhiLi; Soo, Han Sen

2018-05-22

Catalyst deactivation is a persistent problem not only for the scientific community but also in industry. Isolated single-site heterogeneous catalysts have shown great promise to overcome these problems. Here, a versatile anchoring strategy for molecular complex immobilization on a broad range of semiconducting or insulating metal oxide ( e. g., titanium dioxide, mesoporous silica, cerium oxide, and tungsten oxide) nanoparticles to synthesize isolated single-site catalysts has been studied systematically. An oxidatively stable anchoring group, maleimide, is shown to form covalent linkages with surface hydroxyl functionalities of metal oxide nanoparticles by photoclick chemistry. The nanocomposites have been thoroughly characterized by techniques including UV-visible diffuse reflectance spectroscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, infrared spectroscopy, and X-ray absorption spectroscopy (XAS). The IR spectroscopic studies confirm the covalent linkages between the maleimide group and surface hydroxyl functionalities of the oxide nanoparticles. The hybrid nanomaterials function as highly efficient catalysts for essentially quantitative oxidations of terminal and internal alkenes and show molecular catalyst product selectivities even in more eco-friendly solvents. XAS studies verify the robustness of the catalysts after several catalytic cycles. We have applied the photoclick anchoring methodology to precisely control the deposition of a luminescent variant of our catalyst on the metal oxide nanoparticles. Overall, we demonstrate a general approach to use irradiation to anchor molecular complexes on oxide nanoparticles to create recyclable, hybrid, single-site catalysts that function with high selectivity in a broad range of solvents. We have achieved a facile, spatially and temporally controllable photoclick method that can potentially be extended to other ligands, catalysts, functional molecules, and surfaces.

Reactivity of a Carbon-Supported Single-Site Molybdenum Dioxo Catalyst for Biodiesel Synthesis

Energy Technology Data Exchange (ETDEWEB)

Mouat, Aidan R.; Lohr, Tracy L.; Wegener, Evan C.; Miller, Jeffrey T.; Delferro, Massimiliano; Stair, Peter C.; Marks, Tobin J.

2016-08-23

A single-site molybdenum dioxo catalyst, (O_c)₂Mo(=O)₂@C, was prepared via direct grafting of MoO₂Cl₂(dme) (dme = 1,2-dimethoxyethane) on high-surface- area activated carbon. The physicochemical and chemical properties of this catalyst were fully characterized by N₂ physisorption, ICP-AES/OES, PXRD, STEM, XPS, XAS, temperature-programmed reduction with H₂ (TPR-H₂), and temperature-programmed NH₃ desorption (TPD-NH₃). The single-site nature of the Mo species is corroborated by XPS and TPR-H₂ data, and it exhibits the lowest reported MoO_x Tmax of reduction reported to date, suggesting a highly reactive MoVI center. (O_c)₂Mo(=O)₂@C catalyzes the transesterification of a variety of esters and triglycerides with ethanol, exhibiting high activity at moderate temperatures (60-90 °C) and with negligible deactivation. (O_c)₂Mo(=O)₂@C is resistant to water and can be recycled at least three times with no loss of activity. The transesterification reaction is determined experimentally to be first order in [ethanol] and first order in [Mo] with ΔH = 10.5(8) kcal mol^-1 and ΔS = -32(2) eu. The low energy of activation is consistent with the moderate conditions needed to achieve rapid turnover. This highly active carbon-supported single-site molybdenum dioxo species is thus an efficient, robust, and lowcost catalyst with significant potential for transesterification processes.

Study of site layout in the Rokkasho site

International Nuclear Information System (INIS)

Sato, Kazuyoshi; Tamura, Kousaku; Yagenji, Akira; Sekiya, Shigeki; Takahashi, Hideo; Neyatani, Yuzuru; Uehara, Masaharu; Motohashi, Keiichi; Hashimoto, Masayoshi; Ogino, Shunji; Nagamatsu, Nobuhide

2006-03-01

The Final Design Report (FDR) of the International Thermonuclear Experimental Reactor (ITER) was published on July 2001 as a summary of the Engineering Design Activity (EDA). After the EDA, site dependent design has been investigated for the invitation of ITER toward Rokkasho Site (Iyasakadai area) in Aomori prefecture. This report describes the results of site layout of major buildings and structures of ITER in the Rokkasho-Site. The data of the ground near the site and the results of site dependent design in Japan were applied to this study. Through this study, the most appropriate site layout has been constructed with satisfaction of following conditions. (1) Bedrock level at the tokamak complex building is relatively high and it can be reduced the cost of excavation and foundation work. (2) Total amount of excavation soil for site preparation is minimized and the flexibility of the layout is ensured with flat ground level. (3) Accessibility of human and equipments, reduction of noise and vibration to the environment can be obtained. Total length of ducts and piping between buildings in site is minimized. (author)

Energy-conserving site-design case study, Radisson, New York. Final report

Energy Technology Data Exchange (ETDEWEB)

1979-12-01

Radisson is a 2,950-acre new community currently being developed by the New York State Urban Development Corporation and located in central New York, 12 miles north-west of Syracuse. Case-study sites selected for this project are a 95-acre residential site and the 51-acre Town Center of the new community. Development on the Residential Site is a low-density (2.8 dwelling units/acre) mixture of single-family, townhouse and multi-family units. Development on the Town Center site is a mixture of small-scale commercial use (144,000 sq. ft.) and 330+ multi-family dwelling units. Energy-conserving plans developed for both sites have focused on passive measures to reduce energy use for space heating. Utility-system options have been identified for both sites, but require further study as to feasibility and cost. This report summarizes energy savings and cost differentials due to passive measures incorporated in both the residential and Town Center Plans. The future implementation schedule, also discussed, summarizes the procedures an schedule required for implementation of the passive measures, as well as further study required for the development of utility-system options. 4 tables.

Robotic laparoendoscopic single-site surgery: From present to future

Directory of Open Access Journals (Sweden)

Ayhan Verit

2012-01-01

Full Text Available The continued effort of improving cosmesis and reducing morbidity in urologic surgery has given rise to novel alternatives to traditional minimally invasive techniques: Laparoendoscopic Single-site Surgery (LESS and Natural Orifice Transluminal Endoscopic Surgery (NOTES. Despite the development of specialized access devices and instruments, the performance of complex procedures using LESS has been challenging due to loss of triangulation and instrument clashing. A robotic interface may represent the key factor in overcoming the critical restrictions related to NOTES and LESS. Although encouraging, current clinical evidence related to R-LESS remains limited as the current da Vinci® robotic platform has not been specifically designed for LESS. Robotic innovations are imminent and are likely to govern major changes to the current landscape of scarless surgery.

Towards observing the encounter of the T7 DNA replication fork with a lesion site at the Single molecule level

KAUST Repository

Shirbini, Afnan

2017-05-01

Single-molecule DNA flow-stretching assays have been a powerful approach to study various aspects on the mechanism of DNA replication for more than a decade. This technique depends on flow-induced force on a bead attached to a surface-tethered DNA. The difference in the elastic property between double-strand DNA (long) and single-strand DNA (short) at low regime force allows the observation of the beads motion when the dsDNA is converted to ssDNA by the replisome machinery during DNA replication. Here, I aim to develop an assay to track in real-time the encounter of the bacteriophage T7 replisome with abasic lesion site inserted on the leading strand template. I optimized methods to construct the DNA substrate that contains the abasic site and established the T7 leading strand synthesis at the single molecule level. I also optimized various control experiments to remove any interference from the nonspecific interactions of the DNA with the surface. My work established the foundation to image the encounter of the T7 replisome with abasic site and to characterize how the interactions between the helicase and the polymerase could influence the polymerase proofreading ability and its direct bypass of this highly common DNA damage type.

Induction of prophage lambda by chlorinated organics: Detection of some single-species/single-site carcinogens

Energy Technology Data Exchange (ETDEWEB)

DeMarini, D.M.; Brooks, H.G. (Environmental Protection Agency, Research Triangle Park, NC (United States))

1992-01-01

Twenty-eight chlorinated organic compounds were evaluated for their ability to induce DNA damage using the Microscreen prophage-induction assay in Escherichia coli. Comparison of the performance characteristics of the prophage-induction and Salmonella assays to rodent carcinogenicity assays showed that the prophage-induction assay had a somewhat higher specificity than did the Salmonella assay (70% vs. 50%); sensitivity, concordance, and positive and negative predictivity were similar for the two microbial assays. The Microscreen prophage-induction assay failed to detect eight carcinogens, perhaps due to toxicity or other unknown factors; five of these eight carcinogens were detected by the Salmonella assay. However, the prophage-induction assay did detect six carcinogens that were not detected by the Salmonella assay, and five of these were single-species, single-site carcinogens, mostly mouse liver carcinogens. Some of these carcinogens, such as the chloroethanes, produce free radicals, which may be the basis for their carcinogenicity and ability to induce prophage. The prophage-induction (or other SOS) assay may be useful in identifying some genotoxic chlorinated carcinogens that induce DNA damage that do not revert the standard Salmonella tester strains.

No difference in incidence of port-site hernia and chronic pain after single-incision laparoscopic cholecystectomy versus conventional laparoscopic cholecystectomy

DEFF Research Database (Denmark)

Christoffersen, Mette W; Brandt, Erik; Oehlenschläger, Jacob

2015-01-01

and matched 1:2 with patients subjected to CLC using pre-defined criteria. Follow-up data were obtained from the Danish National Patient Registry, mailed patient questionnaires, and clinical examination. A port-site hernia was defined as a repair for a port-site hernia or clinical hernia located at one......BACKGROUND: Conventional laparoscopic cholecystectomy (CLC) is regarded as the gold standard for cholecystectomy. However, single-incision laparoscopic cholecystectomy (SLC) has been suggested to replace CLC. This study aimed at comparing long-term incidences of port-site hernia and chronic pain...... after SLC versus CLC. METHODS: We conducted a matched cohort study based on prospective data (Jan 1, 2009-June 1, 2011) from the Danish Cholecystectomy Database with perioperative information and clinical follow-up. Consecutive patients undergoing elective SLC during the study period were included...

Is Laparoendoscopic Single-Site Adrenalectomy a Feasible Alternative in Treating Aldosterone-Producing Adenoma?

Directory of Open Access Journals (Sweden)

Che-Hsiung Wu

2016-01-01

Full Text Available Objective. To compare laparoendoscopic single-site (LESS and conventional multiport adrenalectomy in patients with aldosterone-producing adenoma (APA. Material and Methods. We retrospectively reviewed patients who had been clinically confirmed with unilateral APA and who underwent LESS or multiport adrenalectomy between 2009 and 2014. Perioperative data were obtained for all patients. Blood pressure and the levels of serum aldosterone, renin, and potassium were checked periodically. Results. We identified 45 APA patients in the LESS group and 71 in the multiport group. The baseline characteristics were matched between two groups. All adrenalectomies were completed successfully, except one with laparoscopic conversion in the single-port group and one open conversion in the multiport group. After a mean follow-up around one year, there were no significant group differences in the improvement of hypertension, number of types of medication taken, and cure of hypokalemia after operation. Conclusions. Our study confirm that LESS adrenalectomy achieved similar clinical and functional outcomes as conventional multiport adrenalectomy for management of unilateral APA.

Ligand-tailored single-site silica supported titanium catalysts: Synthesis, characterization and towards cyanosilylation reaction

Science.gov (United States)

Xu, Wei; Li, Yani; Yu, Bo; Yang, Jindou; Zhang, Ying; Chen, Xi; Zhang, Guofang; Gao, Ziwei

2015-01-01

A successive anchoring of Ti(NMe2)4, cyclopentadiene and a O-donor ligand, 1-hydroxyethylbenzene (PEA), 1,1‧-bi-2-naphthol (Binol) or 2,3-dihydroxybutanedioic acid diethyl ester (Tartrate), on silica was conducted by SOMC strategy in moderate conditions. The silica, monitored by in-situ Fourier transform infrared spectroscopy (in-situ FT-IR), was pretreated at different temperatures (200, 500 and 800 °C). The ligand tailored silica-supported titanium complexes were characterized by in-situ FT-IR, 13C CP MAS-NMR, X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure (XANES) and elemental analysis in detail, verifying that the surface titanium species are single sited. The catalytic activity of the ligand tailored single-site silica supported titanium complexes was evaluated by a cyanosilylation of benzaldehyde. The results showed that the catalytic activity is dependent strongly on the dehydroxylation temperatures of silica and the configuration of the ligands.

Structural features of single-stranded integron cassette attC sites and their role in strand selection.

Directory of Open Access Journals (Sweden)

Marie Bouvier

2009-09-01

Full Text Available We recently showed that cassette integration and deletion in integron platforms were occurring through unconventional site-specific recombination reactions involving only the bottom strand of attC sites. The lack of sequence conservation among attC sites led us to hypothesize that sequence-independent structural recognition determinants must exist within attC sites. The structural data obtained from a synaptic complex of the Vibrio cholerae integrase with the bottom strand of an attC site has shown the importance of extra helical bases (EHB inside the stem-loop structure formed from the bottom strand. Here, we systematically determined the contribution of three structural elements common to all known single-stranded attC site recombination substrates (the EHBs, the unpaired central spacer (UCS, and the variable terminal structure (VTS to strand choice and recombination. Their roles have been evaluated in vivo in the attIxattC reaction context using the suicide conjugation assay we previously developed, but also in an attCxattC reaction using a deletion assay. Conjugation was used to deliver the attC sites in single-stranded form. Our results show that strand choice is primarily directed by the first EHB, but the presence of the two other EHBs also serves to increase this strand selection. We found that the structure of the central spacer is essential to achieve high level recombination of the bottom strand, suggesting a dual role for this structure in active site exclusion and for hindering the reverse reaction after the first strand exchange. Moreover, we have shown that the VTS has apparently no role in strand selectivity.

Single-site SBA-15 supported zirconium catalysts. Synthesis, characterization and toward cyanosilylation reaction

International Nuclear Information System (INIS)

Xu, Wei; Yu, Bo; Zhang, Ying; Chen, Xi; Zhang, Guofang; Gao, Ziwei

2015-01-01

Graphical abstract: Ligand-modified signal-site SBA-15 supported zirconium catalysts were synthesized by SOMC method and characterized by a variety of techniques. The zirconium surface complexes show high catalytic efficiency for cyanosilylation of benzaldehyde. - Highlights: • Some Zr active species have been anchored on the surface of SBA-15 by SOMC technique. • The structures of the Zr species have been characterized by a variety of techniques. • The anchored Zr species are single-sited surface complexes. • The Zr surface complexes are catalytic active for cyanosilylation of benzaldehyde. - Abstract: A successive anchoring of Zr(NMe 2 ) 4 , cyclopentadiene and a O-donor ligand, 1-hydroxyethylbenzene (PEA), 1,1′-bi-2-naphthol (Binol) or 2,3-dihydroxybutanedioic acid diethyl ester (Tartrate), on dehydroxylated SBA-15 pretreated at 500 °C for 16 h (SBA-15 -500 ) was conducted by SOMC strategy in moderate conditions. The dehydoxylation of SBA-15 was monitored by in situ Fourier transform infrared spectroscopy (in situ FT-IR). The ligand-modified SBA-15 -500 supported zirconium complexes were characterized by in situ FT-IR, 13 C CP MAS-NMR, X-ray photoelectron spectroscopy (XPS), inductively coupled plasma mass spectrometry (ICP-MAS) and elemental analysis in detail, verifying that the surface zirconium species are single-sited. The catalytic activity of these complexes was evaluated by cyanosilylation of benzaldehyde. The results showed that the catalytic activity is dependent strongly on the structure of surface species and the configuration of the ligands

INITIAL SINGLE-SHELL TANK (SST) SYSTEM PERFORMANCE ASSESSMENT OF THE HANFORD SITE

International Nuclear Information System (INIS)

JARAYSI, M.N.

2007-01-01

The ''Initial Single-Shell Tank System Performance Assessment for the Hanford Site [1] (SST PA) presents the analysis of the long-term impacts of residual wastes assumed to remain after retrieval of tank waste and closure of the SST farms at the US Department of Energy (DOE) Hanford Site. The SST PA supports key elements of the closure process agreed upon in 2004 by DOE, the Washington State Department of Ecology (Ecology), and the US Environmental Protection Agency (EPA). The SST PA element is defined in Appendix I of the ''Hanford Federal Facility Agreement and Consent Order'' (HFFACO) (Ecology et al. 1989) [2], the document that establishes the overall closure process for the SST and double-shell tank (DST) systems. The approach incorporated in the SST PA integrates substantive features of both hazardous and radioactive waste management regulations into a single analysis. The defense-in-depth approach used in this analysis defined two major engineering barriers (a surface barrier and the grouted tank structure) and one natural barrier (the vadose zone) that will be relied on to control waste release into the accessible environment and attain expected performance metrics. The analysis evaluates specific barrier characteristics and other site features that influence contaminant migration by the various pathways. A ''reference'' case and a suite of sensitivity/uncertainty cases are considered. The ''reference case'' evaluates environmental impacts assuming central tendency estimates of site conditions. ''Reference'' case analysis results show residual tank waste impacts on nearby groundwater, air resources; or inadvertent intruders to be well below most important performance objectives. Conversely, past releases to the soil, from previous tank farm operations, are shown to have groundwater impacts that re significantly above most performance objectives. Sensitivity/uncertainty cases examine single and multiple parameter variability along with plausible alternatives

Socioeconomic Site Study Plan: Draft

International Nuclear Information System (INIS)

1987-07-01

Social and economic issues and concerns of the Deak Smith County site area will be evaluated during site characterization. Effects that the area could experience from a repository project include demographic, economic, community service, fiscal, and social impacts. The Socioeconomic Site Study Plan is designed to provide a strategy to assess the potential for those impacts. The Socioeconomic Site Study Plan is structured to provide an overview of the socioeconomic program requirements, objectives, and activities to be conducted during site characterization. This report will describe the study design and its rationale; data collection, management, and reporting; program schedules and milestones; site study organization and management; and quality assurance issues. 43 refs

[The LESS (Laparo-endoscopic Single-Site) procedure in urology. Technical and clinical aspects].

Science.gov (United States)

Neri, F; Cindolo, L; Gidaro, S; Schips, L

2010-01-01

Minimally invasive urology is rapidly advancing, and single-site laparoscopic surgery is being explored clinically. Such laparoscopic procedures are technically challenging and require an experienced laparoscopic surgeon due to the lack of port placement triangulation and instrument clashing. In the last years several surgeons all over the world have explored the feasibility and safety of LESS using several and different ports, approaches and devices. Hundreds of procedures have been described with overall favorable intraoperative and postoperative outcomes. Our experience consists of more than 30 procedures successfully completed for adrenal, kidney disease and varicocele. To date, LESS could be considered feasible and effective using currently available devices, however it is to be considered as an initial status technique requiring further confirmatory studies and advanced laparoscopic skills.

Robotic-assisted laparoendoscopic single-site surgery (R-LESS) in urology: an evidence-based analysis.

Science.gov (United States)

Barret, E; Sanchez-Salas, R; Ercolani, M; Forgues, A; Rozet, F; Galiano, M; Cathelineau, X

2011-06-01

The objective of this manuscript is to provide an evidence-based analysis of the current status and future perspectives of robotic laparoendoscopic single-site surgery (R-LESS). A PubMed search has been performed for all relevant urological literature regarding natural orifice transluminal endoscopic surgery (NOTES) and laparoendoscopic single-site surgery (LESS). All clinical and investigative reports for robotic LESS and NOTES procedures in the urological literature have been considered. A significant number of clinical urological procedures have been successfully completed utilizing R-LESS procedures. The available experience is limited to referral centers, where the case volume is sufficient to help overcome the challenges and learning curve of LESS surgery. The robotic interface remains the best fit for LESS procedures but its mode of use continues to evolve in attempts to improve surgical technique. We stand today at the dawn of R-LESS surgery, but this approach may well become the standard of care in the near future. Further technological development is needed to allow widespread adoption of the technique.

Single-site SBA-15 supported zirconium catalysts. Synthesis, characterization and toward cyanosilylation reaction

Energy Technology Data Exchange (ETDEWEB)

Xu, Wei; Yu, Bo; Zhang, Ying; Chen, Xi; Zhang, Guofang, E-mail: gfzhang@snnu.edu.cn; Gao, Ziwei, E-mail: zwgao@snnu.edu.cn

2015-01-15

Graphical abstract: Ligand-modified signal-site SBA-15 supported zirconium catalysts were synthesized by SOMC method and characterized by a variety of techniques. The zirconium surface complexes show high catalytic efficiency for cyanosilylation of benzaldehyde. - Highlights: • Some Zr active species have been anchored on the surface of SBA-15 by SOMC technique. • The structures of the Zr species have been characterized by a variety of techniques. • The anchored Zr species are single-sited surface complexes. • The Zr surface complexes are catalytic active for cyanosilylation of benzaldehyde. - Abstract: A successive anchoring of Zr(NMe{sub 2}){sub 4}, cyclopentadiene and a O-donor ligand, 1-hydroxyethylbenzene (PEA), 1,1′-bi-2-naphthol (Binol) or 2,3-dihydroxybutanedioic acid diethyl ester (Tartrate), on dehydroxylated SBA-15 pretreated at 500 °C for 16 h (SBA-15{sub -500}) was conducted by SOMC strategy in moderate conditions. The dehydoxylation of SBA-15 was monitored by in situ Fourier transform infrared spectroscopy (in situ FT-IR). The ligand-modified SBA-15{sub -500} supported zirconium complexes were characterized by in situ FT-IR, {sup 13}C CP MAS-NMR, X-ray photoelectron spectroscopy (XPS), inductively coupled plasma mass spectrometry (ICP-MAS) and elemental analysis in detail, verifying that the surface zirconium species are single-sited. The catalytic activity of these complexes was evaluated by cyanosilylation of benzaldehyde. The results showed that the catalytic activity is dependent strongly on the structure of surface species and the configuration of the ligands.

Energy conserving site design case study: Shenandoah, Georgia. Final report

Energy Technology Data Exchange (ETDEWEB)

1980-01-01

The case study examines the means by which energy conservation can be achieved at an aggregate community level by using proper planning and analytical techniques for a new town, Shenandoah, Georgia, located twenty-five miles southwest of Atlanta's Hartsfield International Airport. A potentially implementable energy conservation community plan is achieved by a study team examining the land use options, siting characteristics of each building type, alternate infrastructure plans, possible decentralized energy options, and central utility schemes to determine how community energy conservation can be achieved by use of pre-construction planning. The concept for the development of mixed land uses as a passively sited, energy conserving community is based on a plan (Level 1 Plan) that uses the natural site characteristics, maximizes on passive energy siting requirement, and allows flexibility for the changing needs of the developers. The Level 2 Plan is identical with Level 1 plan plus a series of decentraized systems that have been added to the residential units: the single-family detached, the apartments, and the townhouses. Level 3 Plan is similar to the Level 1 Plan except that higher density dwellings have been moved to areas adjacent to central site. The total energy savings for each plan relative to the conventional plan are indicated. (MCW)

The application of single cell gel electrophoresis or comet assay to human monitoring studies

Directory of Open Access Journals (Sweden)

Valverde Mahara

1999-01-01

Full Text Available Objective. In the search of new human genotoxic biomarkers, the single cell gel electrophoresis assay has been proposed as a sensible alternative. Material and methods. This technique detects principally single strand breaks as well as alkali-labile and repair-retarded sites. Results. Herein we present our experience using the single cell gel electrophoresis assay in human population studies, both occupationally and environmentally exposed. Conclusions. We discuss the assay feasibility as a genotoxic biomarker.

Study of the surface chemistry and morphology of single walled carbon nanotube-magnetite composites

International Nuclear Information System (INIS)

Marquez-Linares, F.; Uwakweh, O.N.C.; Lopez, N.; Chavez, E.; Polanco, R.; Morant, C.; Sanz, J.M.; Elizalde, E.; Neira, C.; Nieto, S.; Roque-Malherbe, R.

2011-01-01

The study of the morphologies of the single walled carbon nanotube (SWCNT), magnetite nanoparticles (MNP), and the composite based on them was carried with combined X-ray diffraction (XRD), Raman spectroscopy (RS), scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM). These techniques together with thermogravimetric analyses (TGA) and diffuse reflectance infrared transform spectroscopy (DRIFTS) confirmed the production of pure single phases, and that the composite material consisted of MNP attached to the outer surface of the SWCNT. The Moessbauer spectroscopy (MS) research showed the presence of a large quantity of Lewis acid sites in the highly dispersed magnetite particles supported on the SWCNT outer surface. The DRIFTS carbon dioxide adsorption study of the composites revealed significant adsorption of carbon dioxide, fundamentally in the Lewis acid sites. Then, the Lewis acid sites were observed to be catalytically active. Further, the electron exchange between the Lewis acid sites and the basic or amphoteric adsorbed molecules could influence the magnetic properties of the magnetite. Consequently, together with this first ever use of MS in the study of Lewis acid sites, this investigation revealed the potential of the composites for catalytic and sensors applications. -- Graphical abstract: A large amount of Lewis acid sites were found in the highly dispersed magnetite which is supported on the SWCNT outer surface. Display Omitted Research highlights: → The obtained materials were completely characterized with XRD, Raman and SEM-TEM. → DRIFT, TGA and adsorption of the composites allowed understand the material formation. → This is the first report of a study of Lewis sites by Moessbauer spectroscopy.

Alkali-labile sites and post-irradiation effects in single-stranded DNA induced by H radicals

International Nuclear Information System (INIS)

Lafleur, M.V.M.; Heuvel, N. van; Woldhuis, J.; Loman, H.

1978-01-01

Single-stranded phiX174 DNA in aqueous solutions has been irradiated in the absence of oxygen, under conditions in which H radicals react with the DNA. It was shown that H radical reactions result in breaks, which contribute approximately 10 per cent inactivation. Further, two types of alkali-labile sites were formed. One was lethal and gave rise to single-strand breaks by alkali and was most probably identical with post-irradiation heat damage and contributed about 33 per cent to the inactivation mentioned above. The other consisted of non-lethal damage, partly dihydropyrimidine derivatives, and was converted to lethal damage by alkali. This followed from experiments in which the DNA was treated with osmium-tetroxide, which oxidized thymine to 5,6-dihydroxydihydrothymine. Treatment with alkali of this DNA gave the same temperature dependence as found for the non-lethal alkali-labile sites in irradiated DNA. A similar temperature dependence was found for dihydrothymine and irradiated pyrimidines with alkali. (author)

Candidate reagents and procedures for the dissolution of Hanford Site single-shell tank sludges

International Nuclear Information System (INIS)

Schulz, W.W.; Kupfer, M.J.

1991-10-01

At least some of the waste in the 149 single-shell tanks (SST) at the US Department of Energy (DOE) Hanford Site will be retrieved, treated, and disposed of. Although the importance of devising efficient and cost-effective sludge dissolution procedures has long been recognized, a concerted bench-scale effort to devise and test such procedures with actual solids representative of those in Hanford Site SSTs has not been performed. Reagents that might be used, either individually or serially, to dissolve sludges include HNO 3 , HNO 3 -oxalic acid, and HNO 3 -HF. This report consolidates and updates perspectives and recommendations concerning reagents and procedures for dissolving Hanford Site SST and selected double-shell tank (DST) sludges. The principal objectives of this report are as follows: (1) Compile and review existing experimental data on dissolution of actual Hanford Site SST and DST sludges. (2) Further inform Hanford Site engineers and scientists concerning the utility of combinations of thermally unstable complexants (TUCS) reagents and various reducing agents for dissolving SST and DST sludges. (This latter technology has recently been explored at the Argonne National Laboratory.) (3) Provide guidance in laying out a comprehensive experimental program to develop technology for dissolving all types of Hanford Site SST and DST sludges. 6 refs., 1 fig., 4 tabs

EPR and optical absorption studies of paramagnetic molecular ion (VO2+) in Lithium Sodium Acid Phthalate single crystal

Science.gov (United States)

Subbulakshmi, N.; Kumar, M. Saravana; Sheela, K. Juliet; Krishnan, S. Radha; Shanmugam, V. M.; Subramanian, P.

2017-12-01

Electron Paramagnetic Resonance (EPR) spectroscopic studies of VO2+ ions as paramagnetic impurity in Lithium Sodium Acid Phthalate (LiNaP) single crystal have been done at room temperature on X-Band microwave frequency. The lattice parameter values are obtained for the chosen system from Single crystal X-ray diffraction study. Among the number of hyperfine lines in the EPR spectra only two sets are reported from EPR data. The principal values of g and A tensors are evaluated for the two different VO2+ sites I and II. They possess the crystalline field around the VO2+ as orthorhombic. Site II VO2+ ion is identified as substitutional in place of Na1 location and the other site I is identified as interstitial location. For both sites in LiNaP, VO2+ are identified in octahedral coordination with tetragonal distortion as seen from the spin Hamiltonian parameter values. The ground state of vanadyl ion in the LiNaP single crystal is dxy. Using optical absorption data the octahedral and tetragonal parameters are calculated. By correlating EPR and optical data, the molecular orbital bonding parameters have been discussed for both sites.

Site locality identification study: Hanford Site. Volume II. Data cataloging

International Nuclear Information System (INIS)

1980-07-01

Data compilation and cataloging for the candidate site locality identification study were conducted in order to provide a retrievable data cataloging system for the present siting study and future site evaluation and licensng processes. This task occurred concurrently with and also independently of other tasks of the candidate site locality identification study. Work in this task provided the data utilized primarily in the development and application of screening and ranking processes to identify candidate site localities on the Hanford Site. The overall approach included two steps: (1) data acquisition and screening; and (2) data compilation and cataloging. Data acquisition and screening formed the basis for preliminary review of data sources with respect to their probable utilization in the candidate site locality identification study and review with respect to the level of completeness and detail of the data. The important working assumption was that the data to be used in the study be based on existing and available published and unpublished literature. The data compilation and cataloging provided the basic product of the Task; a retrievable data cataloging system in the form of an annotated reference list and key word index and an index of compiled data. The annotated reference list and key word index are cross referenced and can be used to trace and retrieve the data sources utilized in the candidate site locality identification study

The concept, reality and utility of single-site heterogeneous catalysts (SSHCs).

Science.gov (United States)

Thomas, John Meurig

2014-05-07

Very substantial advances have recently been made in the design and construction of solid catalysts and in elucidating both their mode of operation and the factors that determine their selectivity and longevity. This Perspective explains how and why such progress has been made. One important factor, the deployment of single-site heterogeneous and enzymatic catalysts, used either alone or in conjunction with other strategies, including metabolic engineering, enables a multitude of new products (for example, environmentally clean jet fuel) to be readily manufactured. In a practical sense SSHCs enable the advantages of homogeneous and to a lesser degree enzymatic catalysts to be united with those of heterogeneous ones. With the aid of the vastly increasing families of nanoporous solids, desired catalytically active sites may be engineered in atomic detail on their inner, accessible surfaces, thereby opening up new possibilities in synthetic organic chemistry - as in the smooth formation of C-C and C[double bond, length as m-dash]N bonds in a number of intermolecular reactions - as well as in photocatalysts and in fluidized catalytic cracking of hydrocarbons.

Compact teleoperated laparoendoscopic single-site robotic surgical system: Kinematics, control, and operation.

Science.gov (United States)

Isaac-Lowry, Oran Jacob; Okamoto, Steele; Pedram, Sahba Aghajani; Woo, Russell; Berkelman, Peter

2017-12-01

To date a variety of teleoperated surgical robotic systems have been developed to improve a surgeon's ability to perform demanding single-port procedures. However typical large systems are bulky, expensive, and afford limited angular motion, while smaller designs suffer complications arising from limited motion range, speed, and force generation. This work was to develop and validate a simple, compact, low cost single site teleoperated laparoendoscopic surgical robotic system, with demonstrated capability to carry out basic surgical procedures. This system builds upon previous work done at the University of Hawaii at Manoa and includes instrument and endoscope manipulators as well as compact articulated instruments designed to overcome single incision geometry complications. A robotic endoscope holder was used for the base, with an added support frame for teleoperated manipulators and instruments fabricated mostly from 3D printed parts. Kinematics and control methods were formulated for the novel manipulator configuration. Trajectory following results from an optical motion tracker and sample task performance results are presented. Results indicate that the system has successfully met the goal of basic surgical functionality while minimizing physical size, complexity, and cost. Copyright © 2017 John Wiley & Sons, Ltd.

Four-electron deoxygenative reductive coupling of carbon monoxide at a single metal site

Science.gov (United States)

Buss, Joshua A.; Agapie, Theodor

2016-01-01

Carbon dioxide is the ultimate source of the fossil fuels that are both central to modern life and problematic: their use increases atmospheric levels of greenhouse gases, and their availability is geopolitically constrained. Using carbon dioxide as a feedstock to produce synthetic fuels might, in principle, alleviate these concerns. Although many homogeneous and heterogeneous catalysts convert carbon dioxide to carbon monoxide, further deoxygenative coupling of carbon monoxide to generate useful multicarbon products is challenging. Molybdenum and vanadium nitrogenases are capable of converting carbon monoxide into hydrocarbons under mild conditions, using discrete electron and proton sources. Electrocatalytic reduction of carbon monoxide on copper catalysts also uses a combination of electrons and protons, while the industrial Fischer-Tropsch process uses dihydrogen as a combined source of electrons and electrophiles for carbon monoxide coupling at high temperatures and pressures. However, these enzymatic and heterogeneous systems are difficult to probe mechanistically. Molecular catalysts have been studied extensively to investigate the elementary steps by which carbon monoxide is deoxygenated and coupled, but a single metal site that can efficiently induce the required scission of carbon-oxygen bonds and generate carbon-carbon bonds has not yet been documented. Here we describe a molybdenum compound, supported by a terphenyl-diphosphine ligand, that activates and cleaves the strong carbon-oxygen bond of carbon monoxide, enacts carbon-carbon coupling, and spontaneously dissociates the resulting fragment. This complex four-electron transformation is enabled by the terphenyl-diphosphine ligand, which acts as an electron reservoir and exhibits the coordinative flexibility needed to stabilize the different intermediates involved in the overall reaction sequence. We anticipate that these design elements might help in the development of efficient catalysts for

DNA deformability changes of single base pair mutants within CDE binding sites in S. Cerevisiae centromere DNA correlate with measured chromosomal loss rates and CDE binding site symmetries

Directory of Open Access Journals (Sweden)

Marx Kenneth A

2006-03-01

Full Text Available Abstract Background The centromeres in yeast (S. cerevisiae are organized by short DNA sequences (125 bp on each chromosome consisting of 2 conserved elements: CDEI and CDEIII spaced by a CDEII region. CDEI and CDEIII are critical sequence specific protein binding sites necessary for correct centromere formation and following assembly with proteins, are positioned near each other on a specialized nucleosome. Hegemann et al. BioEssays 1993, 15: 451–460 reported single base DNA mutants within the critical CDEI and CDEIII binding sites on the centromere of chromosome 6 and quantitated centromere loss of function, which they measured as loss rates for the different chromosome 6 mutants during cell division. Olson et al. Proc Natl Acad Sci USA 1998, 95: 11163–11168 reported the use of protein-DNA crystallography data to produce a DNA dinucleotide protein deformability energetic scale (PD-scale that describes local DNA deformability by sequence specific binding proteins. We have used the PD-scale to investigate the DNA sequence dependence of the yeast chromosome 6 mutants' loss rate data. Each single base mutant changes 2 PD-scale values at that changed base position relative to the wild type. In this study, we have utilized these mutants to demonstrate a correlation between the change in DNA deformability of the CDEI and CDEIII core sites and the overall experimentally measured chromosome loss rates of the chromosome 6 mutants. Results In the CDE I and CDEIII core binding regions an increase in the magnitude of change in deformability of chromosome 6 single base mutants with respect to the wild type correlates to an increase in the measured chromosome loss rate. These correlations were found to be significant relative to 105 Monte Carlo randomizations of the dinucleotide PD-scale applied to the same calculation. A net loss of deformability also tends to increase the loss rate. Binding site position specific, 4 data-point correlations were also

Single-site properties of U impurities doped in La2Zn17 (abstract)

Science.gov (United States)

Suzuki, H.; Anzai, K.; Takagi, S.

1997-04-01

Thermodynamic and transport properties of heavy Fermion (HF) U compounds show similar behavior to HF Ce compounds. Although most of the magnetic properties of HF Ce compounds can be qualitatively understood on the basis of the impurity Kondo model, no such consensus for HF U compounds has been reached. In addition to this, the single-site properties of U impurities are not understood so well, in contrast to the case of Ce impurities. Recent works for dilute U systems reported new features as are not seen in dilute Ce systems. We have investigated a dilute-U2Zn17 system of (La1-zUz)2Zn17 in order to reveal the single U ion site properties of this system by preparing single crystals. The impurity contributions to various physical quantities such as ρimp(T), χimp(T), and Cimp(T) can be scaled by the U concentration between z=0.025 and 0.05, and the system is considered as in the dilute limit still for z=0.05. The electrical resistivity shows the typical impurity-Kondo upturn at low temperatures. The electronic specific-heat coefficient is strongly enhanced (γimp≈1.5 J/K2 mole U) and about 4 times as large as that for dense U2Zn17. Suppressions of the Kondo effect by the magnetic field are seen in γimp(H) and magnetoresistance. The relatively large anisotropy in χimp(T) indicates an existence of the crystal field. These features of this system will be explained in terms of the Kondo effect in the presence of the crystal field.

The development of a code of practice for single house on-site wastewater treatment in Ireland.

Science.gov (United States)

Gill, L W

2011-01-01

The performance of six separate percolation areas was intensively monitored to ascertain the attenuation effects of unsaturated subsoils with respect to on-site wastewater effluent: three sites receiving septic tank effluent, the other three sites receiving secondary treated effluent. The development of a biomat across the percolation areas receiving secondary treated effluent was restricted on these sites compared to those sites receiving septic tank effluent. This created significant differences in terms of the hydraulic loading on the percolation areas with implications for the transport and attenuation of indicator microorganisms and nitrogen down through the subsoils and into the groundwater. The results of this work have formed a large input into the production of a new Code of Practice Wastewater Treatment and Disposal Systems Serving Single Houses. This has led to changes in the design of on-site hydraulic loading from 180 L per capita per day (L/c.d) down to 150 L/c.d. The range of acceptable subsoils receiving septic tank effluent has narrowed for more highly permeable subsoils following a series of tracer studies using bacteriophages. However, the range has been extended for lower permeability subsoils (range 0.08 down to 0.06 m/d) receiving secondary treated effluent in order to encourage the effluent to spread further along the trenches. The maximum individual length of percolation trenches receiving secondary effluent has also been reduced to 10 m to encourage dispersion on a wider area. This paper thus highlights how research can directly feed into a Code of Practice.

Positron annihilation lifetime and photoluminescence studies on single crystalline ZnO

Energy Technology Data Exchange (ETDEWEB)

Sarkar, A [Department of Physics, Bangabasi Morning College, 19 Rajkumar Chakraborty Sarani, Kolkata 700 009 (India); Chakrabarti, Mahuya [Department of Physics, University of Calcutta, 92 Acharya Prafulla Chandra Road, Kolkata 700009 (India); Ray, S K [Department of Physics and Meteorology, Indian Institute of Technology, Kharagpur (India); Bhowmick, D; Sanyal, D, E-mail: dirtha@vecc.gov.in [Variable Energy Cyclotron Centre, 1/AF, Bidhannagar, Kolkata 700064 (India)

2011-04-20

The room temperature positron annihilation lifetime for single crystalline ZnO has been measured as 164 {+-} 1 ps. The single component lifetime value is very close to but higher than the theoretically predicted value of {approx} 154 ps. Photoluminescence study (at 10 K) indicates the presence of hydrogen and other defects, mainly acceptor related, in the crystal. Defects related to a lower open volume than zinc vacancies, presumably a complex with two hydrogen atoms, are the major trapping sites in the sample. The bulk positron lifetime in ZnO is expected to be a little less than 164 ps.

Positron annihilation lifetime and photoluminescence studies on single crystalline ZnO

Science.gov (United States)

Sarkar, A.; Chakrabarti, Mahuya; Ray, S. K.; Bhowmick, D.; Sanyal, D.

2011-04-01

The room temperature positron annihilation lifetime for single crystalline ZnO has been measured as 164 ± 1 ps. The single component lifetime value is very close to but higher than the theoretically predicted value of ~ 154 ps. Photoluminescence study (at 10 K) indicates the presence of hydrogen and other defects, mainly acceptor related, in the crystal. Defects related to a lower open volume than zinc vacancies, presumably a complex with two hydrogen atoms, are the major trapping sites in the sample. The bulk positron lifetime in ZnO is expected to be a little less than 164 ps.

Positron annihilation lifetime and photoluminescence studies on single crystalline ZnO

International Nuclear Information System (INIS)

Sarkar, A; Chakrabarti, Mahuya; Ray, S K; Bhowmick, D; Sanyal, D

2011-01-01

The room temperature positron annihilation lifetime for single crystalline ZnO has been measured as 164 ± 1 ps. The single component lifetime value is very close to but higher than the theoretically predicted value of ∼ 154 ps. Photoluminescence study (at 10 K) indicates the presence of hydrogen and other defects, mainly acceptor related, in the crystal. Defects related to a lower open volume than zinc vacancies, presumably a complex with two hydrogen atoms, are the major trapping sites in the sample. The bulk positron lifetime in ZnO is expected to be a little less than 164 ps.

Carbon monoxide adsorption on low-silica zeolites: from single to dual and to multiple cation sites.

Science.gov (United States)

Otero Areán, C; Rodríguez Delgado, M; López Bauçà, C; Vrbka, L; Nachtigall, P

2007-09-07

Infrared spectra of CO adsorbed on the Al-rich Na-A zeolite were analysed by using a combined theoretical and experimental approach, showing that such spectra cannot be interpreted by assigning each IR band to CO interacting with a specific type of single cation site. This concept, which usually works well for high-silica zeolites, should not be uncritically extended to Al-rich zeolites that are crowded with cations in configurations which lead to preferential formation of CO adsorption complexes involving more than one cation site.

Comparison of different sets of instruments for laparoendoscopic single-site surgery in a surgical simulator with novices.

Science.gov (United States)

Wang, Dong; Shi, Long-Qing; Wang, Jing-Min; Jiang, Xiao-Hua; Ji, Zhen-Ling

2016-04-01

Given the parallel entry of working instruments through a single incision in laparoendoscopic single-site surgery, loss of triangulation in the abdominal cavity and counteracting movements of the instruments are inevitable obstacles. Some specially designed devices have emerged to ameliorate these challenges. Twenty-four novice participants were randomized into four groups using assigned instruments, conventional straight instruments, single-curved instruments, double-curved instruments and articulating instruments, respectively, to perform two basic tasks (peg transferring and pattern cutting) 14 times in a modified simulator. A test of the tasks and a resection of the intestine segment of a rat were performed. The task scores and evaluation of intraoperative skills during the resection of the intestine segment were recorded. The instrument of modified National Aeronautics and Space Administration Task Load Index (NASA-TLX) was completed. The task scores of the groups using single-curved instruments and articulating instruments were better than the other two groups on the simulator tasks, consistent with the evaluation of intraoperative skills during the resection of intestine segment. As the proficiency with the instruments increased, the task scores improved, as demonstrated by the learning curve. The workload measured by the modified NASA-TLX tool demonstrated that the groups using articulating instruments and double-curved instruments had a heavier workload in most of the categories compared with the other two groups. Single-curved and articulating instruments are more effective than conventional straight and double-curved devices, and are favourable in laparoendoscopic single-site surgery for novice learners. © 2013 Royal Australasian College of Surgeons.

Ovarian Suspension With Adjustable Sutures: An Easy and Helpful Technique for Facilitating Laparoendoscopic Single-Site Gynecologic Surgery.

Science.gov (United States)

Chen, Kuo-Hu; Chen, Li-Ru; Seow, Kok-Min

2015-01-01

To describe a method of ovarian suspension with adjustable sutures (OSAS) for facilitating laparoendoscopic single-site gynecologic surgery (LESS) and to investigate the effect of OSAS on LESS. Prospective cohort study (Canadian Task Force classification: II-2). University teaching hospital. One hundred seventy-eight patients with benign 5- to 15-cm cystic ovarian tumors who underwent LESS with OSAS (suspension group, n = 90) and without OSAS (control group, n = 88). For patients who underwent OSAS (suspension group), 1 end of double-head straight needles with a polypropylene suture was inserted into the pelvic cavity through the abdominal skin to penetrate the cyst or ovarian parenchyma and puncture outside the abdominal skin. After cutting off the needles, both sides of the remaining suture were held together by a clamp, without knotting, so that the manipulator could "lift," "loosen," or "fix" the stitches to adjust the tension. The average time to create OSAS was 2.9 min. For the suspension and control groups, the average blood loss was 81.4 and 131.8 mL (p < .001), and the operative time was 42.0 and 61.3 min (p < .001), respectively. There were no significant differences in the incidence of complications (5.6% vs 9.1%; p = .365), but there were significant differences in conversions to standard non-single-site laparoscopy (5.6% vs 15.9%; p = .025) and laparotomy (1.1% vs 6.8%; p = .040). Logistic regression analysis revealed that the ratios of conversion to standard non-single-site laparoscopy (odds ratio [OR], 0.126; 95% confidence interval [CI], 0.311-0.508) and laparotomy (OR, 0.032; 95% CI, 0.002-0.479) were much lower in the suspension group; the risk of complications was comparable (OR, 0.346; 95% CI, 0.085-1.403). OSAS is an easy, safe, and feasible method that offers advantages during LESS. Although routine use of OSAS is not necessary, OSAS can be considered during LESS to facilitate the surgery. Copyright © 2015 AAGL. Published by Elsevier Inc. All

Transumbilical laparoendoscopic single-site radical prostatectomy and cystectomy with the aid of a transurethral port: a feasibility study.

Science.gov (United States)

Su, Jian; Zhu, Qingyi; Yuan, Lin; Zhang, Yang; Zhang, Qingling; Wei, Yunfei

2018-01-01

To describe the surgical technique and report early outcomes of transurethral assisted laparoendoscopic single-site (LESS) radical prostatectomy (RP) and LESS radical cystectomy (RC) in a single institution. Between December 2014 and March 2016, a total of 114 LESS RPs and RCs were performed, comprising 68 LESS RPs, 38 LESS RCs with cutaneous ureterostomy (CU) and eight LESS RCs with orthotopic ileal neobladder (OIN). Access was achieved via a single-port, with four channels placed through a transumblical incision. After the apex of prostate was separated from the urethra, a self-developed port ('Zhu's port') was inserted through the urethra to facilitate resection of prostate and urethrovesical anastomosis. The peri-operative and postoperative data were collected and analysed retrospectively. Patients were followed up postoperatively for evidence of long-term side effects. All the procedures were completed successfully. No conversion to conventional laparoscopic surgery was necessary. For LESS RP, the average operating time was 152 min. Estimated blood loss was 117 mL. The mean hospital stay was 16.4 days after surgery. For LESS RC with CU and LESS RC with OIN, the mean operating times were 215 and 328 min, mean estimated blood loss was 175 and 252 mL, and mean hospital stay was 9.4 and 18.2 days, respectively. Six patients required blood transfusion (5.26%). Intra-operative complications occurred in two patients (1.75%), and postoperative complications in nine (7.89%). Fourteen out of 68 (20.6%) patients who underwent LESS RP had positive surgical margins. Follow-up ranged from 10 to 30.6 months. In the prostate cancer cases, good urinary control was observed in 35.3%, 97.1% and 100% of patients at 1, 6 and 12 months after the operation, respectively, while biochemical recurrence was observed in 11.8% patients. In the bladder cancer cases, two patients had local recurrence and two patients had distant metastasis. Our results showed that LESS RP and LESS RC

Defining the learning curve of laparoendoscopic single-site Heller myotomy.

Science.gov (United States)

Ross, Sharona B; Luberice, Kenneth; Kurian, Tony J; Paul, Harold; Rosemurgy, Alexander S

2013-08-01

Initial outcomes suggest laparoendoscopic single-site (LESS) Heller myotomy with anterior fundoplication provides safe, efficacious, and cosmetically superior outcomes relative to conventional laparoscopy. This study was undertaken to define the learning curve of LESS Heller myotomy with anterior fundoplication. One hundred patients underwent LESS Heller myotomy with anterior fundoplication. Symptom frequency and severity were scored using a Likert scale (0 = never/not bothersome to 10 = always/very bothersome). Symptom resolution, additional trocars, and complications were compared among patient quartiles. Median data are presented. Preoperative frequency/severity scores were: dysphagia = 10/8 and regurgitation = 8/7. Additional trocars were placed in 12 patients (10%), of whom all were in the first two quartiles. Esophagotomy/gastrotomy occurred in three patients. Postoperative complications occurred in 9 per cent. No conversions to "open" operations occurred. Length of stay was 1 day. Postoperative frequency/severity scores were: dysphagia = 2/0 and regurgitation = 0/0; scores were less than before myotomy (P Heller myotomy with anterior fundoplication well palliates symptoms of achalasia with no apparent scar. Placement of additional trocars only occurred early in the experience. For surgeons proficient with the conventional laparoscopic approach, the learning curve of LESS Heller myotomy with anterior fundoplication is short and safe, because proficiency is quickly attained.

Site locality identification study: Hanford Site. Volume I. Methodology, guidelines, and screening

International Nuclear Information System (INIS)

1980-07-01

Presented in this report are the results of the site locality identification study for the Hanford Site using a screening process. To enable evaluation of the entire Hanford Site, the screening process was applied to a somewhat larger area; i.e., the Pasco Basin. The study consisted of a series of screening steps that progressively focused on smaller areas which are within the Hanford Site and which had a higher potential for containing suitable repository sites for nuclear waste than the areas not included for further study. Five site localities, designated H-1, H-2, H-3, H-4, H-5 (Figure A), varying in size from approximately 10 to 50 square miles, were identified on the Hanford Site. It is anticipated that each site locality may contain one or more candidate sites suitable for a nuclear waste repository. The site locality identification study began with definition of objectives and the development of guidelines for screening. Three objectives were defined: (1) maximize public health and safety; (2) minimize adverse environmental and socioeconomic impacts; and (3) minimize system costs. The screening guidelines have numerical values that provided the basis for the successive reduction of the area under study and to focus on smaller areas that had a higher likelihood of containing suitable sites

Very late complications of cervical arthroplasty: results of 2 controlled randomized prospective studies from a single investigator site.

Science.gov (United States)

Hacker, Francis M; Babcock, Rebecca M; Hacker, Robert J

2013-12-15

Prospective, single-site, randomized, Food and Drug Administration-approved investigational device exemption clinical trials of 2 cervical arthroplasty (CA) devices. To evaluate complications with CA occurring more than 4 years after the surgical procedure in Food and Drug Administration clinical trials of the Bryan and Prestige LP arthroplasty devices. Reports of several randomized clinical studies have shown CA to be a safe and effective alternative to anterior cervical fusion in the treatment of degenerative cervical disc disorders. A majority include follow-up intervals of 4 years or less. Between 2002 and 2006, 94 patients were enrolled in Food and Drug Administration studies of the Bryan and Prestige LP cervical disc devices. Charts, imaging studies, and hospital records were reviewed for those who underwent arthroplasty and returned more than 4 years after their surgical procedure with neck-related pain or dysfunction. Excluding adjacent segment disease that occurred with a similar rate for patients who underwent fusion and arthroplasty, 5 patients, all treated with arthroplasty, returned for evaluation of neck and arm symptoms between 48 and 72 months after surgery. Four patients had peridevice vertebral body bone loss. One patient had posterior device migration and presented with myelopathy. Three required revision surgery and 2 were observed. Four patients maintained follow-up and reported stabilization or improvement in symptoms. Despite their similarities, CA and fusion are not equivalent procedures in this study in regard to very late complications. Similar to large joint arthroplasty, delayed device-related complications may occur with CA. These complications commenced well beyond the time frame for complications associated with more traditional cervical spine procedures. Both patients and surgeons should be aware of the potential for very late device-related complications occurring with CA and the need for revision surgery. 1.

Totally Transanal Laparo-Endoscopic Single-Site ProctoColectomy-Ileoanal J-Pouch (TLPC-J: An Experimental Study of a Novel Approach

Directory of Open Access Journals (Sweden)

Mohammad Reza Vahdad

2015-09-01

Full Text Available Background: The natural orifice transluminal endoscopic surgery (NOTES has become a commonly considered novel approach in the surgical field. The NOTES provide possibility of operation through the natural orifice and decreases the intentional puncture of the systemic organ and subsequent complications. Totally transanal laparo-endoscopic single-site proctoColectomy-Ileoanal J-Pouch (TLPC-J is a novel method in minimally invasive surgery for total colectomy. The main goal of this study is to perform this new method on an animal model, to assess probable complication and to resolve probable issues by using patients that are candidate for total colectomy. Method: Five dogs were prepared in lithotomy position. The TLPC-I procedure consists of endorectal technique with full thickness rectal dissection starting 1 cm orally from the dentate line above the peritoneal reflection and the proximal bowel was replaced into the abdominal cavity. Afterwards, the TriPort system was inserted in the anal canal and mesentrial resection of the total colon, mobilization of a distal ileal segment and intracorporeal suture of an ileal J-loop was accomplished by this system. An incision in the J-loop was conducted transanally. The J-pouch was created with an Endo-GIA® and sutured to the rectal wall. Results: All animals survived and passed stool with clear post operation situation. There was no infection in site of anastomosis. Conclusion: The TLPC-I provides the possibility of surgery without abdominal wall incision and decreases post operation complication such as pain, abdominal wound infection and wound dehiscence. This technique increases the quality of life and surgeons can discharge the patients early.

Laparoendoscopic single-site adrenalectomy versus conventional laparoscopic surgery: a systematic review and meta-analysis of observational studies.

Science.gov (United States)

Wang, Linhui; Wu, Zhenjie; Li, Mingmin; Cai, Chen; Liu, Bing; Yang, Qing; Sun, Yinghao

2013-06-01

To assess the surgical efficacy and potential advantages of laparoendoscopic single-site adrenalectomy (LESS-AD) compared with conventional laparoscopic adrenalectomy (CL-AD) based on published literature. An online systematic search in electronic databasesM including Pubmed, Embase, and the Cochrane Library, as well as manual bibliography searches were performed. All studies that compared LESS-AD with CL-AD were included. The outcome measures were the patient demographics, tumor size, blood loss, operative time, time to resumption of oral intake, hospital stay, postoperative pain, cosmesis satisfaction score, rates of complication, conversion, and transfusion. A meta-analysis of the results was conducted. A total of 443 patients were included: 171 patients in the LESS-AD group and 272 patients in the CL-AD group (nine studies). There was no significant difference between the two groups in any of the demographic parameters expect for lesion size (age: P=0.24; sex: P=0.35; body mass index: P=0.79; laterality: P=0.76; size: P=0.002). There was no significant difference in estimated blood loss, time to oral intake resumption, and length of stay between the two groups. The LESS-AD patients had a significantly lower postoperative visual analog pain score compared with the CL-AD group, but a longer operative time was noted. Both groups had a comparable cosmetic satisfaction score. The two groups had a comparable rate of complication, conversion, and transfusion. In early experience, LESS-AD appears to be a safe and feasible alternative to its conventional laparoscopic counterpart with decreased postoperative pain noted, albeit with a longer operative time. As a promising and emerging minimally invasive technique, however, the current evidence has not verified other potential advantages (ie, cosmesis, recovery time, convalescence, port-related complications, etc.) of LESS-AD.

Single port laparoscopic surgery

DEFF Research Database (Denmark)

Springborg, Henrik; Istre, Olav

2012-01-01

LESS, or laparo-endoscopic single site surgery, is a promising new method in minimally invasive surgery. An increasing number of surgical procedures are being performed using this technique, however, its large-scale adoption awaits results of prospective randomized controlled studies confirming...... potential benefits. Theoretically, cosmetic outcomes, postoperative pain and complication rates could be improved with use of single site surgery. This study describes introduction of the method in a private hospital in Denmark, in which 40 patients have been treated for benign gynecologic conditions....... Although the operations described are the first of their kind reported in Denmark, favorable operating times and very low complication rates are seen. It is the authors' opinion that in addition to being feasible for hysterectomy, single port laparoscopy may become the preferred method for many simple...

Methodology of site protection studies

International Nuclear Information System (INIS)

Farges, L.

1980-01-01

Preliminary studies preceding building of a nuclear facility aim at assessing the choice of a site and establishing operating and control procedures. These studies are of two types. Studies on the impact of environment on the nuclear facility to be constructed form one type and studies on the impact of nuclear facilities on the environment form the second type. A methodology giving a framework to studies of second type is presented. These studies are undertaken to choose suitable sites for nuclear facilities. After a preliminary selection of a site based on the first estimate, a detailed site study is undertaken. The procedure for this consists of five successive phases, namely, (1) an inquiry assessing the initial state of the site, (2) an initial synthesis of accumulated information for assessing the health and safety consequences of releases, (3) laboratory and field studies simulating the movement of waste products for a quantitative assessment of effects, (4) final synthesis for laying down the release limits and radiological control methods, and (5) conclusions based on comparing the data of final synthesis to the limits prescribed by regulations. These five phases are outlined. Role of periodic reassessments after the facility is in operation for same time is explained. (M.G.B.)

Siting analysis and risk assessment for small single-purpose heating reactors

International Nuclear Information System (INIS)

Tarjanne, R.

1979-04-01

Two alternative sites both 10km away from the centre of Helsinki are considered for reactor unit sizes of 400mw and 800mw. The risks associated with a small single-purpose heating reactor is evaluated for normal operation and accident conditions. The evaluation for accident condition is performed for three characteristics accidents. Three pathways are considered in the calculation of the radiation exposure: direct external gamma dose from the release plume, direct gamma radiation from deposited activity on the ground and dose due to inhalation. The risks are compared with the risks from alternative conventional fossil fuelled district heat production methods. The results show that the heating reactor alternative causes an unsignificant risk, which is far less than the risk caused by the fossil-fuelled alternatives

Ground state properties of a spin chain within Heisenberg model with a single lacking spin site

International Nuclear Information System (INIS)

Mebrouki, M.

2011-01-01

The ground state and first excited state energies of an antiferromagnetic spin-1/2 chain with and without a single lacking spin site are computed using exact diagonalization method, within the Heisenberg model. In order to keep both parts of a spin chain with a lacking site connected, next nearest neighbors interactions are then introduced. Also, the Density Matrix Renormalization Group (DMRG) method is used, to investigate ground state energies of large system sizes; which permits us to inquire about the effect of large system sizes on energies. Other quantum quantities such as fidelity and correlation functions are also studied and compared in both cases. - Research highlights: → In this paper we compute ground state and first excited state energies of a spin chain with and without a lacking spin site. The next nearest neighbors are introduced with the antiferromagnetic Heisenberg spin-half. → Exact diagonalization is used for small systems, where DMRG method is used to compute energies for large systems. Other quantities like quantum fidelity and correlation are also computed. → Results are presented in figures with comments. → E 0 /N is computed in a function of N for several values of J 2 and for both systems. First excited energies are also investigated.

Single-port access laparoscopic abdominoperineal resection through the colostomy site: a case report

DEFF Research Database (Denmark)

Lauritsen, Morten; Bulut, O

2012-01-01

Single-port access (SPA) laparoscopic surgery is emerging as an alternative to conventional laparoscopic and open surgery, although its benefits still have to be determined. We present the case of a 87-year-old woman who underwent abdominoperineal resection (APR) with SPA. The abdominal part...... of the operation was performed with a SILS port inserted through the marked colostomy site, and the specimen was removed through the perineum after intersphincteric dissection. Operating time was 317 min. Bleeding was negligible. The specimen measured 26 cm in length. Thirteen lymph nodes were found, 2...

Molecular single photon double K-shell ionization

International Nuclear Information System (INIS)

Penent, F.; Nakano, M.; Tashiro, M.; Grozdanov, T.P.; Žitnik, M.; Carniato, S.; Selles, P.; Andric, L.; Lablanquie, P.; Palaudoux, J.; Shigemasa, E.; Iwayama, H.; Hikosaka, Y.; Soejima, K.; Suzuki, I.H.; Kouchi, N.; Ito, K.

2014-01-01

We have studied single photon double K-shell ionization of small molecules (N 2 , CO, C 2 H 2n (n = 1–3), …) and the Auger decay of the resulting double core hole (DCH) molecular ions thanks to multi-electron coincidence spectroscopy using a magnetic bottle time-of-flight spectrometer. The relative cross-sections for single-site (K −2 ) and two-site (K −1 K −1 ) double K-shell ionization with respect to single K-shell (K −1 ) ionization have been measured that gives important information on the mechanisms of single photon double ionization. The spectroscopy of two-site (K −1 K −1 ) DCH states in the C 2 H 2n (n = 1–3) series shows important chemical shifts due to a strong dependence on the C-C bond length. In addition, the complete cascade Auger decay following single site (K −2 ) ionization has been obtained

Isospecific propylene polymerization with in situ generated bis(phenoxy-amine)zirconium and hafnium single site catalysts.

Science.gov (United States)

Makio, Haruyuki; Prasad, Aitha Vishwa; Terao, Hiroshi; Saito, Junji; Fujita, Terunori

2013-07-07

Bis(phenoxy-imine) Zr and Hf complexes were activated with (i)Bu3Al or (i)Bu2AlH in conjunction with Ph3CB(C6F5)4 and tested as catalysts for propylene polymerization with emphasis on the enantioselectivity of the isospecific species and the single site polymerization characteristics. The isoselective species was identified as the in situ generated bis(phenoxy-amine) complex whose isoselectivity was sensitive to subtle changes in ligand structure. By employing specific substituents at certain key positions the isotacticity reached an extremely high level comparable to high-end commercial isotactic polypropylenes (Tm > 160 °C). Single site polymerization characteristics depended upon the efficiency and selectivity of the in situ imine reduction which is sensitive to the substituent on the imine nitrogen and the reaction conditions. By using (i)Bu2AlH as a reducing agent, quantitative imine reduction can be achieved with a stoichiometric amount of the reducing agent. This lower alkylaluminum loading is beneficial for the catalyst and significantly enhances the polymerization activity and the molecular weight of the resultant polymer.

Nuclear site selection studies

International Nuclear Information System (INIS)

Gharib, A.; Zohoorian Izadpanah, A.A.; Iranmanesh, H.

2000-01-01

It is of special importance, especially from the nuclear safety viewpoint, to select suitable sites for different nuclear structures with the considered future activities. Site selection sometimes involves high costs not necessarily for merely selecting of site but for some preliminary measures to be taken so as the site may have the necessary characteristics. The more suitable the natural characteristics of the site for the considered project, the more successful and efficient the project, the lower the project costs and the longer the project operation period. If so, the project will cause the growth of public culture and sustainable socioeconomic development. This paper is the result of the conclusion of numerous massive reports of this activity in the preliminary phase based on theories, practices and the related safety principles on this ground as well as the application of data and information of the past and a glance to the future. The conception of need for a site for medium structures and nuclear research projects and how to perform this process are presented step by step here with a scientific approach to its selection during the investigations. In this study, it is practically described how the site is selected, by determining and defining the characteristics of research and nuclear projects with medium structures and also its fitting to the optimum site. The discovered sites typically involve the best advantages in technical and economic aspects and no particular contrast with the concerned structures

Laparoendoscopic single-site repair of bladder rupture using a home-made single-port device: initial experience of treatment for a traumatic intraperitoneal bladder rupture.

Science.gov (United States)

Lee, Joo Yong; Kang, Dong Hyuk; Lee, Seung Wook

2012-06-01

We report our initial experience with a laparoendoscopic single-site (LESS) repair of a bladder rupture using a home-made single-port device. A 37-year-old man presented to the emergency department with complaints of voiding difficulty and gross hematuria after blunt trauma. Cystography and computed tomography revealed an intraperitoneal bladder rupture. The patient underwent LESS repair of a bladder rupture using the Alexis wound retractor, which was inserted through the umbilical incision. A home-made single-port device was made by fixing 6½ surgical gloves to the outer rim of the retractor and securing the glove finger to the end of 3 trocars with a tie. Using the flexible laparoscopic instruments and rigid instruments, LESS surgery was performed using a procedure similar to conventional laparoscopic surgery. The patient did not have any voiding problem after removal of the urethral Foley catheter on the 10th postoperative day. To our knowledge, this is the first published report of LESS repair of a traumatic bladder rupture using a home-made single-port device in the literature.

Surgical site infection in lumbar surgeries, pre and postoperative antibiotics and length of stay: a case study

International Nuclear Information System (INIS)

Khan, I.U.; Janjua, M.B.; Hasan, S.; Shah, S.

2009-01-01

Postoperative wound infection also called as surgical site infection (SSI), is a trouble some complication of lumbar spine surgeries and they can be associated with serious morbidities, mortalities and increase resource utilization. With the improvement in diagnostic modalities, proper surgical techniques, antibiotic therapy and postoperative care, infectious complications can result in various compromises afterwards. The objective was to study the relation of surgical site infection in clean lumbar surgeries with the doses of antibiotics. This Retrospective study was conducted at Shifa International Hospital, from January 2006 to March 2008. Methods: Hundred post operated cases of lumber disc prolapse, lumbar stenosis or both studied retrospectively by tracing their operated data from hospital record section for the development of surgical site infection (SSI). The patients were divided into three groups depending upon whether they received single, three or more than three doses of antibiotics respectively. Complete data analyses and cross tabulation done with SPSS version 16. Result: Of 100 cases, only 6% had superficial surgical site infection; only 1 case with co morbidity of hypertension was detected. Twenty-one cases had single dose of antibiotic (Group-I), 59 cases had 3 doses (Group-II) and 20 cases received multiple doses (Group-III). There was no infection in Group-I. Only one patient in Group-II and 5 patients in Group-III developed superficial SSI. While 4 in Group-II, 3 in Group-III, and none of Group-I had >6 days length of stay (LOS). Conclusion The dose of antibiotic directly correlates with the surgical site infection in clean lumbar surgeries. When compared with multiple doses of antibiotics a single preoperative shot of antibiotic is equally effective for patients with SSI. (author)

On the simultaneous deployment of two single-particle mass spectrometers at an urban background and a roadside site during SAPUSS

Directory of Open Access Journals (Sweden)

M. Dall'Osto

2016-08-01

Full Text Available The aerosol time-of-flight mass spectrometer (ATOFMS provides size-resolved information on the chemical composition of single particles with high time resolution. Within SAPUSS (Solving Aerosol Problems by Using Synergistic Strategies, continuous ATOFMS measurements of ambient particles were made simultaneously at two urban locations: urban background (UB site and roadside (RS site in the city of Barcelona (Spain from 17 September to 18 October 2010. Two different instrumental configurations were used: ATOFMS (TSI 3800 with a converging nozzle inlet (high efficiency at about 800–2000 nm at the UB site and ATOFMS (TSI 3800-100 with an aerodynamic lens inlet (high efficiency at about 300–700 nm at the RS site. This is the first time, to our knowledge, that two ATOFMS instruments have been deployed in the same field study. The different instrument configurations had an impact on the observed particle types at the two sites. Nevertheless, 10 particle types were detected at both locations, including local and regional elemental carbon (22.7–58.9 % of total particles, fresh and aged sea salt (1.0–14.6 %, local and regional nitrate-containing aerosols (3–11.6 %, local lead-containing metallic particles (0.1–0.2 %, and transported Fe-nitrate particles (0.8–2.5 %. The ATOFMS at the UB also characterized four particle types: calcium-containing dust (0.9 %, Saharan dust (1.3 %, vanadium-containing particles (0.9 %, and vegetative debris (1.7 %. By contrast, the high statistical counts of fine particles detected at the RS allowed identification of eight particle types. Four of these contained organic nitrogen of primary and secondary origin, which highlights the complex nature of the sources and processes that contribute to this aerosol chemical component. Aminium salts were found related to coarse sulfate-rich particle types, suggesting heterogeneous reaction mechanisms for their formation. The other four particle

Wegner estimate and localization for alloy-type models with sign-changing exponentially decaying single-site potentials

Science.gov (United States)

Leonhardt, Karsten; Peyerimhoff, Norbert; Tautenhahn, Martin; Veselić, Ivan

2015-05-01

We study Schrödinger operators on L2(ℝd) and ℓ2(ℤd) with a random potential of alloy-type. The single-site potential is assumed to be exponentially decaying but not necessarily of fixed sign. In the continuum setting, we require a generalized step-function shape. Wegner estimates are bounds on the average number of eigenvalues in an energy interval of finite box restrictions of these types of operators. In the described situation, a Wegner estimate, which is polynomial in the volume of the box and linear in the size of the energy interval, holds. We apply the established Wegner estimate as an ingredient for a localization proof via multiscale analysis.

Single-Molecule Tethered Particle Motion: Stepwise Analyses of Site-Specific DNA Recombination

Directory of Open Access Journals (Sweden)

Hsiu-Fang Fan

2018-05-01

Full Text Available Tethered particle motion/microscopy (TPM is a biophysical tool used to analyze changes in the effective length of a polymer, tethered at one end, under changing conditions. The tether length is measured indirectly by recording the Brownian motion amplitude of a bead attached to the other end. In the biological realm, DNA, whose interactions with proteins are often accompanied by apparent or real changes in length, has almost exclusively been the subject of TPM studies. TPM has been employed to study DNA bending, looping and wrapping, DNA compaction, high-order DNA–protein assembly, and protein translocation along DNA. Our TPM analyses have focused on tyrosine and serine site-specific recombinases. Their pre-chemical interactions with DNA cause reversible changes in DNA length, detectable by TPM. The chemical steps of recombination, depending on the substrate and the type of recombinase, may result in a permanent length change. Single molecule TPM time traces provide thermodynamic and kinetic information on each step of the recombination pathway. They reveal how mechanistically related recombinases may differ in their early commitment to recombination, reversibility of individual steps, and in the rate-limiting step of the reaction. They shed light on the pre-chemical roles of catalytic residues, and on the mechanisms by which accessory proteins regulate recombination directionality.

New Developments in Robotics and Single-site Gynecologic Surgery.

Science.gov (United States)

Matthews, Catherine A

2017-06-01

Within the last 10 years there have been significant advances in minimal-access surgery. Although no emerging technology has demonstrated improved outcomes or fewer complications than standard laparoscopy, the introduction of the robotic surgical platform has significantly lowered abdominal hysterectomy rates. While operative time and cost were higher in robotic-assisted procedures when the technology was first introduced, newer studies demonstrate equivalent or improved robotic surgical efficiency with increased experience. Single-port hysterectomy has not improved postoperative pain or subjective cosmetic results. Emerging platforms with flexible, articulating instruments may increase the uptake of single-port procedures including natural orifice transluminal endoscopic cases.

ITER site selection studies in Spain

International Nuclear Information System (INIS)

Medrano, M.; Alejaldre, C.; Doncel, J.; Garcia, A.; Ibarra, A.; Jimenez, J.A.; Sanchez de Mora, M.A.; Alcala, F.; Diez, J.E.; Dominguez, M.; Albisu, F.

2003-01-01

The studies carried out to evaluate and select a candidate site for International Thermonuclear Experimental Reactor (ITER) construction in Spain are presented in this paper. The ITER design, completed in July 2001, considered a number of technical requirements that must be fulfilled by the selected site. Several assumptions concerning the ITER site were made in order to carry on the design before final site selection. In the studies undertaken for ITER site selection in Spain, the referred technical requirements and assumptions were applied across the whole of Spain and two areas were identified as being preferential. These areas are on the Mediterranean coast and are situated in the Catalan and Valencian regions. A comparative evaluation based on technical characteristics for the concrete plots, proposed within the preferential areas, has been done. The result of these studies was the selection of a site that was deemed to be the most competitive--Vandellos (Tarragona)--and it was proposed to the European Commission for detailed studies in order to be considered as a possible European site for ITER construction. Another key factor for hosting ITER in Spain, is the licensing process. The present status is summarised in this paper

Site study plan for Transportation, Deaf Smith County Site, Texas: Preliminary draft

International Nuclear Information System (INIS)

1987-06-01

This site study plan describes transportation field studies to be conducted during the characterization of the Deaf Smith County, Texas, site for the US Department of Energy's Salt Repository Project. The studies are needed to identify and assess potential project impacts to transportation infrastructure and systems in the project vicinity and along potential transportation routes to the site across the State of Texas. The studies are also needed to locate and design project transportation facilities, and to evaluate and design impact mitigation. After identifying the transportation information requirements needed to comply with Federal, State, and local regulations and repository program requirements, the site study plan describes the study design and rationale, the field data collection procedures and equipment, the data analysis methods and application of results, the data management strategy, the schedule of field activities, the management of the study, and the study's quality assurance program. The field data collection activities are organized into programs for the characterization of site vicinity rail corridors and highway corridors, characterization of alternative statewide transportation routes, monitoring of site characterization effects on transportation, characterization of aircraft overflight patterns and hazardous material transportation patterns, and assessment of emergency response preparedness along alternative statewide transportation routes. 34 refs., 10 figs., 2 tabs

Redox-active on-surface polymerization of single-site divalent cations from pure metals by a ketone-functionalized phenanthroline

Energy Technology Data Exchange (ETDEWEB)

Skomski, Daniel; Tempas, Christopher D.; Bukowski, Gregory S.; Smith, Kevin A.; Tait, Steven L., E-mail: tait@indiana.edu [Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, Indiana 47405 (United States)

2015-03-14

Metallic iron, chromium, or platinum mixing with a ketone-functionalized phenanthroline ligand on a single crystal gold surface demonstrates redox activity to a well-defined oxidation state and assembly into thermally stable, one dimensional, polymeric chains. The diverging ligand geometry incorporates redox-active sub-units and bi-dentate binding sites. The gold surface provides a stable adsorption environment and directs growth of the polymeric chains, but is inert with regard to the redox chemistry. These systems are characterized by scanning tunnelling microscopy, non-contact atomic force microscopy, and X-ray photoelectron spectroscopy under ultra-high vacuum conditions. The relative propensity of the metals to interact with the ketone group is examined, and it is found that Fe and Cr more readily complex the ligand than Pt. The formation and stabilization of well-defined transition metal single-sites at surfaces may open new routes to achieve higher selectivity in heterogeneous catalysts.

Laparoendoscopic single-site extraperitoneal inguinal hernia repair: initial experience in 10 patients.

Science.gov (United States)

Do, Minh; Liatsikos, Evangelos; Beatty, John; Haefner, Tim; Dunn, Ian; Kallidonis, Panagiotis; Stolzenburg, Jens-Uwe

2011-06-01

Recent technical advances and a trend toward laparoscopic single incision surgery have led us to explore the feasibility of laparoendoscopic single-site (LESS) hernia repair. We present our technique and initial experience with LESS extraperitoneal inguinal hernia repair in 10 consecutive men with unilateral inguinal hernias. Age range was 43.7 (28-64) years. Mean body mass index was 28 (range 24-30). Six were left inguinal hernias. There were six indirect and four direct hernias. Three patients had undergone previous open appendectomy. Incarcerated or bilateral hernias were excluded from our initial series. All cases were performed by three surgeons who were experienced in conventional totally extraperitoneal laparoscopic hernia repair as well as experienced in LESS. A literature review of current single-port inguinal hernia repair data is also presented. The mean operative time was 53 minutes (range 45-65  min). The average length of skin incision was 2.8  cm (range 2.3-3.2  cm). No drain was necessary in any of the patients, while no recordable bleeding was observed. There were no intraoperative or immediate postoperative complications. Hospitalization period was 2 days for all patients. After a limited follow-up of 1 month, there have been no recurrences and no complaints of testicular pain. The results of the current series compare favorably with those found in a literature review. LESS extraperitoneal inguinal hernia repair is both feasible and safe, although more technically demanding than its conventional laparoscopic counterpart. Although the cosmetic result with the former approach may prove superior, there are standing questions regarding the complications and long-term outcome. Randomized and if possible blinded trials that compare conventional and single-incision laparoscopic hernia repair may help to distinguish the most advantageous technique.

Analytical study on spherules from Toungouska explosion site

International Nuclear Information System (INIS)

Jehanno, C.; Robin, E.; Rocchia, R.; Boclet, D.; Danon, J.

1989-01-01

Eighty years after the event, the Tunguska explosion of june 1908, has not found a satisfactory explanation. The cosmic bolide, supposed responsible for the event, has not yet been identified but numerous magnetic spherules have been recovered in the vicinity of the explosion site. Eighty spherules have been studied and compared with the Fe-Ni spherules from the steady micrometeoroid flux. Ninety percents of them cannot be identified with any known micrometeoroid families; their low average iridium content rather suggests a terrestrial origin. Five other spherules are obviously Fe-Ni spherules of the steady micrometeoroid rain and, thus, are unrelated the Tunguska event. Only three of the 80 spherules, consisting of a single iron oxide phase, could have been produced by the event. (author)

Comparative Study of 2D and 3D Optical Imaging Systems: Laparoendoscopic Single-Site Surgery in an Ex Vivo Model.

Science.gov (United States)

Vilaça, Jaime; Pinto, José Pedro; Fernandes, Sandra; Costa, Patrício; Pinto, Jorge Correia; Leão, Pedro

2017-12-01

Usually laparoscopy is performed by means of a 2-dimensional (2D) image system and multiport approach. To overcome the lack of depth perception, new 3-dimensional (3D) systems are arising with the added advantage of providing stereoscopic vision. To further reduce surgery-related trauma, there are new minimally invasive surgical techniques being developed, such as LESS (laparoendoscopic single-site) surgery. The aim of this study was to compare 2D and 3D laparoscopic systems in LESS surgical procedures. All participants were selected from different levels of experience in laparoscopic surgery-10 novices, 7 intermediates, and 10 experts were included. None of the participants had had previous experience in LESS surgery. Participants were chosen randomly to begin their experience with either the 2D or 3D laparoscopic system. The exercise consisted of performing an ex vivo pork cholecystectomy through a SILS port with the assistance of a fixed distance laparoscope. Errors, time, and participants' preference were recorded. Statistical analysis of time and errors between groups was conducted with a Student's t test (using independent samples) and the Mann-Whitney test. In all 3 groups, the average time with the 2D system was significantly reduced after having used the 3D system ( P 3D system. This study suggests that the 3D system may improve the learning curve and that learning from the 3D system is transferable to the 2D environment. Additionally, the majority of participants prefer 3D equipment.

Single-Site Active Iron-Based Bifunctional Oxygen Catalyst for a Compressible and Rechargeable Zinc-Air Battery.

Science.gov (United States)

Ma, Longtao; Chen, Shengmei; Pei, Zengxia; Huang, Yan; Liang, Guojin; Mo, Funian; Yang, Qi; Su, Jun; Gao, Yihua; Zapien, Juan Antonio; Zhi, Chunyi

2018-02-27

The exploitation of a high-efficient, low-cost, and stable non-noble-metal-based catalyst with oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) simultaneously, as air electrode material for a rechargeable zinc-air battery is significantly crucial. Meanwhile, the compressible flexibility of a battery is the prerequisite of wearable or/and portable electronics. Herein, we present a strategy via single-site dispersion of an Fe-N x species on a two-dimensional (2D) highly graphitic porous nitrogen-doped carbon layer to implement superior catalytic activity toward ORR/OER (with a half-wave potential of 0.86 V for ORR and an overpotential of 390 mV at 10 mA·cm -2 for OER) in an alkaline medium. Furthermore, an elastic polyacrylamide hydrogel based electrolyte with the capability to retain great elasticity even under a highly corrosive alkaline environment is utilized to develop a solid-state compressible and rechargeable zinc-air battery. The creatively developed battery has a low charge-discharge voltage gap (0.78 V at 5 mA·cm -2 ) and large power density (118 mW·cm -2 ). It could be compressed up to 54% strain and bent up to 90° without charge/discharge performance and output power degradation. Our results reveal that single-site dispersion of catalytic active sites on a porous support for a bifunctional oxygen catalyst as cathode integrating a specially designed elastic electrolyte is a feasible strategy for fabricating efficient compressible and rechargeable zinc-air batteries, which could enlighten the design and development of other functional electronic devices.

Anti-site defected MoS2 sheet-based single electron transistor as a gas sensor

Science.gov (United States)

Sharma, Archana; Husain, Mushahid; Srivastava, Anurag; Khan, Mohd. Shahid

2018-05-01

To prevent harmful and poisonous CO gas molecules, catalysts are needed for converting them into benign substances. Density functional theory (DFT) calculations have been used to study the adsorption of CO and CO2 gas molecules on the surface of MoS2 monolayer with Mo atom embedded at S-vacancy site (MoS). The strong interaction between Mo metal with pristine MoS2 sheet suggests its strong binding nature. Doping Mo into MoS2 sheet enhances CO and CO2 adsorption strength. The sensing response of MoS-doped MoS2 system to CO and CO2 gas molecules is obtained in the single electron transistor (SET) environment by varying bias voltage. Doping reduces charging energy of the device which results in fast switching of the device from OFF to ON state.

Left Transperitoneal Adrenalectomy with a Laparoendoscopic Single-Site Surgery Combined Technique: Initial Case Reports

Directory of Open Access Journals (Sweden)

Yasuhiro Sumino

2011-01-01

Full Text Available Laparoendoscopic single-site surgery (LESS is a step toward the development of minimally invasive surgery. It is initially difficult for surgeons with limited experience to perform the surgery. We describe two cases of left adrenalectomy with a LESS combined with the addition of an accessory port. After a 2.5-cm skin incision was made at the level of the paraumbilicus to insert the primary 12-mm trocar for the laparoscope, a 5-mm nonbladed trocar was placed through the skin incision side-by-side with the primary trocar. A second 3-mm nonbladed trocar was then placed along the anterior axillary line; a multichannel trocar was not used as a single port. Both adrenalectomies were completed successfully. In patients with a minor adrenal tumor, a combined technique using LESS and an additional port is easier than LESS alone and may, therefore, be a bridge between the conventional laparoscopic approach and LESS.

Site directed recombination

Science.gov (United States)

Jurka, Jerzy W.

1997-01-01

Enhanced homologous recombination is obtained by employing a consensus sequence which has been found to be associated with integration of repeat sequences, such as Alu and ID. The consensus sequence or sequence having a single transition mutation determines one site of a double break which allows for high efficiency of integration at the site. By introducing single or double stranded DNA having the consensus sequence flanking region joined to a sequence of interest, one can reproducibly direct integration of the sequence of interest at one or a limited number of sites. In this way, specific sites can be identified and homologous recombination achieved at the site by employing a second flanking sequence associated with a sequence proximal to the 3'-nick.

Multifunctional Single-Site Catalysts for Alkoxycarbonylation of Terminal Alkynes.

Science.gov (United States)

Chen, Xingkun; Zhu, Hejun; Wang, Wenlong; Du, Hong; Wang, Tao; Yan, Li; Hu, Xiangping; Ding, Yunjie

2016-09-08

A multifunctional copolymer (PyPPh2 -SO3 H@porous organic polymers, POPs) was prepared by combining acidic groups and heterogeneous P,N ligands through the copolymerization of vinyl-functionalized 2-pyridyldiphenylphosphine (2-PyPPh2 ) and p-styrene sulfonic acid under solvothermal conditions. The morphology and chemical structure of the copolymer were evaluated using a series of characterization techniques. Compared with traditional homogeneous Pd(OAc)2 /2-PyPPh2 / p-toluenesulfonic acid catalyst, the copolymer supported palladium catalyst (Pd-PyPPh2 -SO3 H@POPs) exhibited higher activity for alkoxycarbonylation of terminal alkynes under the same conditions. This phenomenon could be attributed to the synergistic effect between the single-site Pd centers, 2-PyPPh2 ligands, and SO3 H groups, the outstanding swelling properties as well as the high enrichment of the reactant concentration by the porous catalyst. In addition, the catalyst could be reused at least 4 times without any apparent loss of activity. The excellent catalytic reactivity and good recycling properties make it an attractive catalyst for industrial applications. This work paves the way for advanced multifunctional porous organic polymers as a new type of platform for heterogeneous catalysis in the future. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A multicenter reproducibility study of single-voxel 1H-MRS of the medial temporal lobe

International Nuclear Information System (INIS)

Traeber, Frank; Block, Wolfgang; Guer, Okan; Schild, Hans H.; Freymann, Nikolaus; Heun, Reinhard; Jessen, Frank; Kucinski, Thomas; Hammen, Thilo; Ende, Gabriele; Pilatus, Ulrich; Hampel, Harald

2006-01-01

Proton magnetic resonance spectroscopy ( 1 H-MRS) has provided evidence for a reduction of N-acetyl-aspartate (NAA) in the medial temporal lobe (MTL) in cerebral disorders such as Alzheimer's Disease. Within the 1 H-MRS study of the German Research Network on Dementia, we determined the multicenter reproducibility of single-voxel 1 H-MRS of the MTL. At five sites with 1.5T MR systems, single-voxel 1 H spectra from the MTL of an identical healthy subject were measured. The same subject was also examined at one of the sites five times to assess intracenter stability. The protocol included water-suppressed spectra with TE 272 ms and TE 30 ms and unsuppressed spectra for absolute quantification of metabolite concentrations. The intracenter reproducibility of absolute NAA concentration, expressed as coefficient of variation (CV), was 1.8%. CV for the concentrations of creatine (Cr), choline (Cho), and myoinositol (MI) and for the ratios NAA/Cr, NAA/Cho, and MI/NAA varied by 11-16%. Intercenter CV was 3.9% for NAA and were below 10% for all other metabolites and metabolic ratios. Our study demonstrates that quantitative assessment of NAA with single-voxel MRS can be performed with high intercenter reproducibility. This is the basis for applying 1 H-MRS in large-scale early recognition and treatment studies in MTL affecting disorders. (orig.)

Ionic Exchange of Metal-Organic Frameworks to Access Single Nickel Sites for Efficient Electroreduction of CO2.

Science.gov (United States)

Zhao, Changming; Dai, Xinyao; Yao, Tao; Chen, Wenxing; Wang, Xiaoqian; Wang, Jing; Yang, Jian; Wei, Shiqiang; Wu, Yuen; Li, Yadong

2017-06-21

Single-atom catalysts often exhibit unexpected catalytic activity for many important chemical reactions because of their unique electronic and geometric structures with respect to their bulk counterparts. Herein we adopt metal-organic frameworks (MOFs) to assist the preparation of a catalyst containing single Ni sites for efficient electroreduction of CO 2 . The synthesis is based on ionic exchange between Zn nodes and adsorbed Ni ions within the cavities of the MOF. This single-atom catalyst exhibited an excellent turnover frequency for electroreduction of CO 2 (5273 h -1 ), with a Faradaic efficiency for CO production of over 71.9% and a current density of 10.48 mA cm -2 at an overpotential of 0.89 V. Our findings present some guidelines for the rational design and accurate modulation of nanostructured catalysts at the atomic scale.

Evolution of segmental anesthesia for Laparo-Endoscopic Single Site (LESS) cholecystectomy.

Science.gov (United States)

Ross, S B; Mangar, D; Karlnoski, R; Patel, R S; Camporesi, E M; Barry, L K; Luberice, K; Sprenker, C J; Rosemurgy, A S

2012-06-01

Transumbilical Laparo-Endoscopic Single Site (LESS) surgery promises improved cosmesis, quick recovery, reduced postoperative pain and shorter length of hospital stay. Since only a simple umbilical incision is used, LESS surgery can be completed with segmental epidural anesthesia. This study describes the evolution of our technique of LESS cholecystectomy from a combination of spinal and epidural anesthesia to thoracic epidural alone and presents our experience with its safety, the observed morbidity, and the reported patient satisfaction. In August 2009, a prospective evaluation of LESS cholecystectomy with regional anesthesia was undertaken. We recruited patients with chronic cholecystitis or symptomatic cholelithasis. Blood loss, operative time, complications, and length of hospital stay were measured. Preoperatively and 14 days postoperatively, outcome and symptom resolution were scored. Fifteen consecutive patients underwent LESS cholecystectomy; first with combined spinal-epidural (CSE), and then with thoracic epidural anesthesia alone. Immediate postoperative pain and discomfort were well tolerated. VAS scores upon admission to PACU were 0.4 (1.7±2.2). At postoperative day 14, the patients scored high values for "Satisfaction", 10 (10±1.0) and "Cosmesis", 10 (9.3±1.5). LESS cholecystectomy with epidural anesthesia can be undertaken safely. Patient satisfaction and cosmesis are particularly prominent amongst our patients. Our experience supports further utilization of epidural anesthesia for selected patients undergoing LESS cholecystectomy.

Studying repair of a single protein-bound nick in vivo using the Flp-nick system

DEFF Research Database (Denmark)

Nielsen, Ida; Andersen, Anni Hangaard; Bjergbæk, Lotte

2012-01-01

The Flp-nick system is a simple in vivo system developed for studying the cellular responses to a protein-bound nick at a single genomic site in the budding yeast Saccharomyces cerevisiae. The Flp-nick system takes advantage of a mutant Flp recombinase that can introduce a nick at a specific Flp ...

SITE-94. Chemical and physical transport parameters for SITE-94

Energy Technology Data Exchange (ETDEWEB)

Andersson, Karin [Chalmers Univ. of Technology, Goeteborg (Sweden). Technical Environmental Planning

1996-02-01

Important parameters are the interactions of radionuclides with solid surfaces, parameters describing the geometrical conditions like porosity, data on water composition (ionic strength, pH, redox conditions, complex formers etc) and data on the solids that may be of importance to the water and radionuclide chemistry. In this report some of these data of relevance for the Aespoe site are discussed. Based on a literature survey, sorption data as well as values for some other parameters have been selected for rock, fracture fillings and bentonite relevant to the chemical conditions in and around a repository at Aespoe. A comparison to data used for earlier, site-specific as well as general, safety assessments of underground repositories has been performed. The data are recommendations for modelling of radionuclide release from a hypothetical high level waste repository at Aespoe. Since the data to a large extent are not based on experimental measurements, more accurate predictions may be expected if more experimental data are available. Before such studies are performed for a specific site, a variational analysis in order to evaluate the importance of the single parameters is recommended. After such a study, the key parameters may be investigated in detail and the modelling can be expected to be more accurate what concerns influence of single parameters. However, the uncertainty in conceptual areas like how to model accurately the long term hydrology of the site etc still remains. 32 refs.

Laparoendoscopic Single-Site Surgery (LESS for a Large Ovarian Tumour: First Clinical Case Report

Directory of Open Access Journals (Sweden)

Yao Dong Chua

2011-01-01

Main Outcome Measure(s. Conversion to standard laparoscopic technique or laparotomy, estimated blood loss, operative time , extent of scarring, occurrence of intra- and perioperative surgical complications, technical adequacy, and clinical outcome. Result(s. No conversion to standard laparoscopic technique or laparotomy, and no intraoperative or postoperative complications were observed. Total operative time was 99 minutes. The patient was discharged home on postoperative day one. Conclusion(s. Laparoendoscopic single-site bilateral salpingo-oophorectomy of a large ovarian tumour is feasible with standard laparoscopic instruments. It is safe and effective, with good results in terms of excellent cosmesis and minimal postoperative pain.

Single site and conventional totally extraperitoneal techniques for uncomplicated inguinal hernia repair: A comparative study.

Science.gov (United States)

de Araújo, Felipe Brandão Corrêa; Starling, Eduardo Simão; Maricevich, Marco; Tobias-Machado, Marcos

2014-10-01

To demonstrate the feasibility of endoscopic extraperitoneal single site (EESS) inguinal hernia repair and compare it outcomes with the conventional totally extraperitoneal (TEP) technique. TEP inguinal hernia repair is a widely accepted alternative to conventional open technique with several perioperative advantages. Transumbilical laparoendoscopic singlesite surgery (LESS) is an emerging approach and has been reported for a number of surgical procedures with superior aesthetic results but other advantages need to be proven. Thirty-eight uncomplicated inguinal hernias were repaired by EESS approach between January 2010 and January 2011. All procedures were performed through a 25 cm infraumbilical incision using the Alexis wound retractor attached to a surgical glove and three trocars. Body mass index, age, operative time, blood loss, complications, conversion rate, analgesia requirement, hospital stay, return to normal activities and patient satisfaction with aesthetic results were analysed and compared with the last 38 matched-pair group of patients who underwent a conventional TEP inguinal hernia repair by the same surgeon. All procedures were performed successfully with no conversion. In both unilateral and bilateral EESS inguinal repairs, the mean operative time was longer than conventional TEP (55± 20 vs. 40± 15 min, P = 0.049 and 70± 15 vs. 55± 10 min, P = 0.014). Aesthetic result was superior in the EESS group (2.88± 0.43 vs. 2.79± 0.51, P = 0.042). There was no difference between the two approaches regarding blood loss, complications, hospital stay, time until returns to normal activities and analgesic requirement. EESS inguinal hernia repair is safe and effective, with superior cosmetic results in the treatment of uncomplicated inguinal hernias. Other advantages of this new technique still need to be proven.

Study of Aerosol Optical Properties Over Two Sites in the Foothills of the Central Himalayas

Science.gov (United States)

Rupakheti, D.; Kang, S.; Cong, Z.; Rupakheti, M.; Tripathee, L.; Panday, A. K.; Holben, B.

2018-04-01

Atmospheric aerosol possesses impacts on climate system and ecological environments, human health and agricultural productivity. The environment over Himalayas and Tibetan Plateau region are continuously degraded due to the transport of pollution from the foothills of the Himalayas; mostly the Indo-Gangetic Plain (IGP). Thus, analysis of aerosol optical properties over two sites; Lumbini and Kathmandu (the southern slope of central Himalayas) using AERONET's CIMEL sun photometer were conducted in this study. Aerosol optical depth (AOD at 500 nm), angstrom exponent (α or AE), volume size distribution (VSD), single scattering albedo (SSA) and asymmetry parameter (AP) were studied for 2013-2014 and the average AOD was found to be: 0.64 ± 0.41 (Lumbini) and 0.45 ± 0.30 (Kathmandu). The average AE was found to be: 1.25 ± 0.24 and 1.26 ± 0.18 respectively for two sites. The relation between AOD and AE was used to discriminate the aerosol types over these sites which indicated anthropogenic, mixed and biomass burning origin aerosol constituted the major aerosol types in Lumbini and Kathmandu. A clear bi-modal distribution of aerosol volume size was observed with highest volume concentration during the post-monsoon season in fine mode and pre-monsoon season in coarse mode (Lumbini) and highest value over both modes during pre-monsoon season in Kathmandu. The single scattering albedo (SSA) and asymmetry parameter (AP) analyses suggested aerosols over the Himalayan foothills sites are dominated by absorbing and anthropogenic aerosols from urban and industrial activities and biomass burning. Long-term studies are essential to understand and characterize the nature of aerosol over this research gap zone.

Current status and future perspectives in laparoendoscopic single-site and natural orifice transluminal endoscopic urological surgery.

Science.gov (United States)

Autorino, Riccardo; Stein, Robert J; Lima, Estevão; Damiano, Rocco; Khanna, Rakesh; Haber, Georges-Pascal; White, Michael A; Kaouk, Jihad H

2010-05-01

Objective of this study is to provide an evidence-based analysis of the current status and future perspectives of scarless urological surgery. A PubMed search has been performed for all relevant urological literature regarding natural orifice transluminal endoscopic surgery (NOTES) and laparoendoscopic single-site surgery (LESS). In addition, experience with LESS and NOTES at our own institution has been considered. All clinical and investigative reports for LESS and NOTES procedures in the urological literature have been considered. A wide variety of clinical procedures in urology have been successfully completed by using LESS techniques. Thus far, experience with NOTES has largely been investigational, although early clinical reports are emerging. Further development of instrumentation and platforms is necessary for both techniques to become more widely adopted throughout the urological community.

Evaluation of a Single-Beam Sonar System to Map Seagrass at Two Sites in Northern Puget Sound, Washington

Science.gov (United States)

Stevens, Andrew W.; Lacy, Jessica R.; Finlayson, David P.; Gelfenbaum, Guy

2008-01-01

Seagrass at two sites in northern Puget Sound, Possession Point and nearby Browns Bay, was mapped using both a single-beam sonar and underwater video camera. The acoustic and underwater video data were compared to evaluate the accuracy of acoustic estimates of seagrass cover. The accuracy of the acoustic method was calculated for three classifications of seagrass observed in underwater video: bare (no seagrass), patchy seagrass, and continuous seagrass. Acoustic and underwater video methods agreed in 92 percent and 74 percent of observations made in bare and continuous areas, respectively. However, in patchy seagrass, the agreement between acoustic and underwater video was poor (43 percent). The poor agreement between the two methods in areas with patchy seagrass is likely because the two instruments were not precisely colocated. The distribution of seagrass at the two sites differed both in overall percent vegetated and in the distribution of percent cover versus depth. On the basis of acoustic data, seagrass inhabited 0.29 km2 (19 percent of total area) at Possession Point and 0.043 km2 (5 percent of total area) at the Browns Bay study site. The depth distribution at the two sites was markedly different. Whereas the majority of seagrass at Possession Point occurred between -0.5 and -1.5 m MLLW, most seagrass at Browns Bay occurred at a greater depth, between -2.25 and -3.5 m MLLW. Further investigation of the anthropogenic and natural factors causing these differences in distribution is needed.

Report of JLC site study group

CERN Document Server

Hasegawa, T; Yamashita, S

2003-01-01

This study group selected some good sites for construction of JLC (Electron-Positron Linear Collider) on the basis of investigation of data and field survey. The aims, activity, use of underground of private land, conditions of site, selection of site at present and future, summary and proposal are reported. 9 sites (Hidaka, Kitakami, Murayama, Abukuma, Kitaibaraki, Aichi and Gifu, Takamatsu, Hiroshima and Seburi range) are selected for the construction on the basis of firm ground and 4 sites (Okinawa, Harima, Tsukuba and Mutsuogawara) for development and researches. 9 sites area consists of plutonic rock or old strata of Paleozoic era. Many problems in each site are reported. There are three following proposals; 1) the self-governing communities of the sites have to understand JLC and start to construct it by information, 2) a site evaluation committee consists of specialist of civil engineering, building, social and natural environment and disaster prevention and 3) the vibration test should be carried out ...

How Customer Facing Professionals Adapt to Changing Customer Needs in a Digital Environment: A Single Case Study

Science.gov (United States)

Hendriks, Stefan

2017-01-01

This qualitative single case study explored how customer facing professionals (CFPs) adapt to changing customer needs in a digital environment. This study focuses on: (1) Changing customer needs; (2) Competencies needed in a digital environment; (3) How they learn; and (4) What factors help or hinder their success. The site is a global Human…

Single house on-site grey water treatment using a submerged membrane bioreactor for toilet flushing.

Science.gov (United States)

Fountoulakis, M S; Markakis, N; Petousi, I; Manios, T

2016-05-01

Wastewater recycling has been and continues to be practiced all over the world for a variety of reasons including: increasing water availability, combating water shortages and drought, and supporting environmental and public health protection. Nowadays, one of the most interesting issues for wastewater recycling is the on-site treatment and reuse of grey water. During this study the efficiency of a compact Submerged Membrane Bioreactor (SMBR) system to treat real grey water in a single house in Crete, Greece, was examined. In the study, grey water was collected from a bathtub, shower and washing machine containing significant amounts of organic matter and pathogens. Chemical oxygen demand (COD) removal in the system was approximately 87%. Total suspended solids (TSS) were reduced from 95mgL(-1) in the influent to 8mgL(-1) in the effluent. The efficiency of the system to reduce anionic surfactants was about 80%. Fecal and total coliforms decreased significantly using the SMBR system due to rejection, by the membrane, used in the study. Overall, the SMBR treatment produces average effluent values that would satisfy international guidelines for indoor reuse applications such as toilet flushing. Copyright © 2016 Elsevier B.V. All rights reserved.

A multicenter reproducibility study of single-voxel {sup 1}H-MRS of the medial temporal lobe

Energy Technology Data Exchange (ETDEWEB)

Traeber, Frank; Block, Wolfgang; Guer, Okan; Schild, Hans H. [University of Bonn, Department of Radiology, Bonn (Germany); Freymann, Nikolaus; Heun, Reinhard; Jessen, Frank [University of Bonn, Department of Psychiatry, Bonn (Germany); Kucinski, Thomas [University of Hamburg, Department of Neuroradiology, Hamburg (Germany); Hammen, Thilo [University of Erlangen, Department of Psychiatry, Erlangen (Germany); Ende, Gabriele [Central Institute of Mental Health, NMR Research in Psychiatry, Mannheim (Germany); Pilatus, Ulrich [University of Frankfurt, Department of Neuroradiology, Frankfurt (Germany); Hampel, Harald [University of Munich, Department of Psychiatry, Munich (Germany)

2006-05-15

Proton magnetic resonance spectroscopy ({sup 1}H-MRS) has provided evidence for a reduction of N-acetyl-aspartate (NAA) in the medial temporal lobe (MTL) in cerebral disorders such as Alzheimer's Disease. Within the {sup 1}H-MRS study of the German Research Network on Dementia, we determined the multicenter reproducibility of single-voxel {sup 1}H-MRS of the MTL. At five sites with 1.5T MR systems, single-voxel {sup 1}H spectra from the MTL of an identical healthy subject were measured. The same subject was also examined at one of the sites five times to assess intracenter stability. The protocol included water-suppressed spectra with TE 272 ms and TE 30 ms and unsuppressed spectra for absolute quantification of metabolite concentrations. The intracenter reproducibility of absolute NAA concentration, expressed as coefficient of variation (CV), was 1.8%. CV for the concentrations of creatine (Cr), choline (Cho), and myoinositol (MI) and for the ratios NAA/Cr, NAA/Cho, and MI/NAA varied by 11-16%. Intercenter CV was 3.9% for NAA and were below 10% for all other metabolites and metabolic ratios. Our study demonstrates that quantitative assessment of NAA with single-voxel MRS can be performed with high intercenter reproducibility. This is the basis for applying {sup 1}H-MRS in large-scale early recognition and treatment studies in MTL affecting disorders. (orig.)

General siting study 95. Siting of a deep repository for spent nuclear fuel

International Nuclear Information System (INIS)

1995-10-01

General Siting Study 95 is a detailed description of the work carried out to put the siting of a deep repository in a national and regional context. The report is based on SKB's siting factors, which have been applied on a national scale. Different factors of importance or of possible importance for the long-term radiological safety, technology, land and environment as well as society are described and evaluated. This report is the overall description on general siting studies which the government considered that SKB should report in connection with the RD and D Programme 95. 121 refs, 40 figs

General siting study 95. Siting of a deep repository for spent nuclear fuel

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-10-01

General Siting Study 95 is a detailed description of the work carried out to put the siting of a deep repository in a national and regional context. The report is based on SKB`s siting factors, which have been applied on a national scale. Different factors of importance or of possible importance for the long-term radiological safety, technology, land and environment as well as society are described and evaluated. This report is the overall description on general siting studies which the government considered that SKB should report in connection with the RD and D Programme 95. 121 refs, 40 figs.

A single splice site mutation in human-specific ARHGAP11B causes basal progenitor amplification

Science.gov (United States)

Florio, Marta; Namba, Takashi; Pääbo, Svante; Hiller, Michael; Huttner, Wieland B.

2016-01-01

The gene ARHGAP11B promotes basal progenitor amplification and is implicated in neocortex expansion. It arose on the human evolutionary lineage by partial duplication of ARHGAP11A, which encodes a Rho guanosine triphosphatase–activating protein (RhoGAP). However, a lack of 55 nucleotides in ARHGAP11B mRNA leads to loss of RhoGAP activity by GAP domain truncation and addition of a human-specific carboxy-terminal amino acid sequence. We show that these 55 nucleotides are deleted by mRNA splicing due to a single C→G substitution that creates a novel splice donor site. We reconstructed an ancestral ARHGAP11B complementary DNA without this substitution. Ancestral ARHGAP11B exhibits RhoGAP activity but has no ability to increase basal progenitors during neocortex development. Hence, a single nucleotide substitution underlies the specific properties of ARHGAP11B that likely contributed to the evolutionary expansion of the human neocortex. PMID:27957544

International Journal of Humanistic Studies: Site Map

African Journals Online (AJOL)

International Journal of Humanistic Studies: Site Map. Journal Home > About the Journal > International Journal of Humanistic Studies: Site Map. Log in or Register to get access to full text downloads.

Site-specific ligation of anthracene-1,8-dicarboxylates to an Mn12 core: a route to the controlled functionalisation of single-molecule magnets.

Science.gov (United States)

Pacchioni, Mirko; Cornia, Andrea; Fabretti, Antonio C; Zobbi, Laura; Bonacchi, Daniele; Caneschi, Andrea; Chastanet, Guillaume; Gatteschi, Dante; Sessoli, Roberta

2004-11-21

A novel single-molecule magnet of the Mn12 family, [Mn12O12(O2CC6H5)8(L)4(H2O)4].8CH2Cl2, has been synthesised by site-specific ligand exchange using a tailor-made dicarboxylate (L2-), which leads to selective occupation of axial binding sites.

Single-Molecule Interfacial Electron Transfer

Energy Technology Data Exchange (ETDEWEB)

Lu, H. Peter [Bowling Green State Univ., Bowling Green, OH (United States). Dept. of Chemistry and Center for Photochemical Sciences

2017-11-28

This project is focused on the use of single-molecule high spatial and temporal resolved techniques to study molecular dynamics in condensed phase and at interfaces, especially, the complex reaction dynamics associated with electron and energy transfer rate processes. The complexity and inhomogeneity of the interfacial ET dynamics often present a major challenge for a molecular level comprehension of the intrinsically complex systems, which calls for both higher spatial and temporal resolutions at ultimate single-molecule and single-particle sensitivities. Combined single-molecule spectroscopy and electrochemical atomic force microscopy approaches are unique for heterogeneous and complex interfacial electron transfer systems because the static and dynamic inhomogeneities can be identified and characterized by studying one molecule at a specific nanoscale surface site at a time. The goal of our project is to integrate and apply these spectroscopic imaging and topographic scanning techniques to measure the energy flow and electron flow between molecules and substrate surfaces as a function of surface site geometry and molecular structure. We have been primarily focusing on studying interfacial electron transfer under ambient condition and electrolyte solution involving both single crystal and colloidal TiO₂ and related substrates. The resulting molecular level understanding of the fundamental interfacial electron transfer processes will be important for developing efficient light harvesting systems and broadly applicable to problems in fundamental chemistry and physics. We have made significant advancement on deciphering the underlying mechanism of the complex and inhomogeneous interfacial electron transfer dynamics in dyesensitized TiO₂ nanoparticle systems that strongly involves with and regulated by molecule-surface interactions. We have studied interfacial electron transfer on TiO₂ nanoparticle surfaces by using ultrafast single

Nuclear power plant site selection: a case study

International Nuclear Information System (INIS)

Lugasi, Y.; Mehrez, A.; Sinuany-Stern, Z.

1985-01-01

Selecting the site for a nuclear power plant involves the evaluation of numerous criteria and the professional judgment of various experts. The Israel Atomic Energy Commission has been concerned with the problem of selecting a site for a nuclear power station. Previous studies have been performed by the commission to identify potential sites. There were initial screenings where potential sites were chosen according to various minimal criteria and international standards. Only sites that met all the criteria were chosen. A study was made to find the most preferred site among the potential sites that met all the criteria. Two mathematical approaches were used: Keeney's multiattribute utility function and Saaty's eigenvalue prioritization technique. Both models ranked the same site as the most desirable; however, the models differed in their ranking of the other sites

One-site versus two-site phacotrabeculectomy: a prospective randomized study

Directory of Open Access Journals (Sweden)

Moschos MM

2015-08-01

Full Text Available Marilita M Moschos,1 Irini P Chatziralli,2 Michael Tsatsos3 1First Department of Ophthalmology, University of Athens, 2Second Department of Ophthalmology, Ophthalmiatrion Athinon, Athens, Greece; 3Department of Ophthalmology, Cambridge University Hospital NHS, Cambridge, UK Purpose: The purpose of this study is to compare the efficacy and safety of one-site and two-site combined phacotrabeculectomy with foldable posterior chamber intraocular lens implantation.Methods: Thirty-four patients (41 eyes with glaucoma and cataract were randomly assigned to undergo either a one-site (22 eyes or a two-site (19 eyes combined procedure. One-site approach consisted of a standard superior phacotrabeculectomy with a limbus-based conjunctival flap, while two-site approach consisted of a clear cornea phacoemulsification and a separate superior trabeculectomy with a limbus-based conjunctival flap.Results: Mean follow-up period was 54 months (standard deviation [SD] 2.3. Mean preoperative intraocular pressure (IOP in the one-site group was 21.3 mmHg (SD 2.8 and in the two-site group was 21.8 mmHg (SD 3.0 (P>0.1. Mean postoperative IOP significantly decreased in both groups compared to the preoperative level and was 15.6 mmHg (SD 3.5 in the one-site group and 14.9 mmHg (SD 2.7 in the two-site group. Three months later, the difference between the two groups was not statistically significant (P=0.058. The one-site group required significantly more medications than the two-site group (P=0.03. Best-corrected visual acuity (BCVA improved similarly in both groups, but there was less postoperative (induced astigmatism in the two-site group in a marginal statistical level (P=0.058. Intra- and postoperative complications were comparable in the two groups.Conclusion: Both techniques yielded similar results concerning final BCVA and IOP reduction. However, the two-site group had less induced astigmatism and a better postoperative IOP control with less required

Site Response Analysis Using DeepSoil: Case Study of Bangka Site, Indonesia

Energy Technology Data Exchange (ETDEWEB)

Iswanto, Eko Rudi; Yee, Eric [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

2015-10-15

Indonesia government declared through Act No. 17 year 2007 on the National Long-Term Development Plant Year 2005-2025 and Presidential Decree No. 5 year 2006 on the National Energy Policy (Indonesia 2007; Indonesia 2006), that nuclear energy is stated as a part of the national energy system. In order to undertake the above national policy, National Nuclear Energy Agency of Indonesia, as the promotor for the utilization of nuclear energy will conduct site study, which is a part of infrastructure preparation for NPP construction. Thorough preparation and steps are needed to operate an NPP and it takes between 10 to 15 years from the preliminary study (site selection, financial study, etc.) up to project implementation (manufacturing, construction, commissioning). During project implementation, it is necessary to prepare various documents relevant for permit application such as Safety Evaluation Report for site permit, Preliminary Safety Analysis Report and Environment Impact Assessment Report for construction permit. Considering the continuously increasing electricity energy demand, it is necessary to prepare for alternative NPP sites. The safety requirements of NPP's are stringent; amongst the various requirements is the ability to safely shut down in the wake of a possible earthquake. Ground response analysis of a potential site therefore needs to be carried out, parameter that affect the resistance of an NPP to earthquakes such as peak strain profiles is analysed. The objective of this paper is to analyse the ground response of the selected site for a NPP, using The Mw 7.9 in Sikuai Island, West Sumatra on September 12, 2007 as present input motion. This analysis will be carried out using a ground response analysis program, DeepSoil. In addition to this, an attempt was made to define the site specific input motion characteristics of the selected site for use in DeepSoil (DeepSoil 5.0). A site investigation at the WB site was performed primarily on the PS

Totally extraperitoneal (TEP) bilateral hernioplasty using the Single Site® robotic da Vinci platform (DV-SS TEP): description of the technique and preliminary results.

Science.gov (United States)

Cestari, A; Galli, A C; Sangalli, M N; Zanoni, M; Ferrari, M; Roviaro, G

2017-06-01

Laparoendoscopic single site totally extraperitoneal (TEP) hernia repair showed to be a feasible alternative to conventional laparoscopic hernia repair; nevertheless single site surgery, with the loss of instruments triangulation can be a demanding procedure. To overcome those hurdles, the Single Site® (SS) platform of the da Vinci (DV) Si robotic system enables to perform surgical procedures through a 25-mm skin incision, with a stable 3D vision and restoring an adequate triangulation of the surgical instruments. We present in details the technique and the preliminary results of DV-SS TEP, to our knowledge the first cases reported in literature. In March 2016, three consecutive male patients (mean age 46.6 years-mean BMI 25.3) with bilateral symptomatic inguinal hernia were submitted to DV-SS TEP in our institutions. Feasibility, codification of the technique, operative time and perioperative outcomes were recorded. All the procedures were completed as scheduled, with no conversion to other techniques. Mean operative time was 98.6 min, ranging between 155 and 55 min, reflecting the learning curve of the operating room team on this new procedure. No intraoperative or postoperative complications were experienced and all the patients were discharged within 24 h after surgery. Patients reported satisfactory postoperative course, with no recurrence of inguinal hernia and satisfaction in cosmetic result at 6-month follow-up. DV-SS TEP inguinal hernia repair showed to be feasible and effective surgical option for bilateral groin hernia repair. Patients' outcome was uneventful, with optimal cosmetic results. Further studies comparing this innovative technique to TEP or LESS TEP should be promoted.

Photoelectron diffraction studies of small adsorbates on single crystal surfaces

International Nuclear Information System (INIS)

Pascal, Mathieu

2002-01-01

The structural determination of small molecules adsorbed on single crystal surfaces has been investigated using scanned energy mode photoelectron diffraction (PhD). The experimental PhD data were compared to theoretical models using a simulation program based on multiple scattering calculations. Three adsorption systems have been examined on Ag(110), Cu(110) and Cu(111) crystals. The structure of the (2x1)-O adsorption phase on Ag(110) revealed that the O atoms occupied the long bridge site and are almost co-planar with the top layer of Ag atoms. The best agreement between multiple scattering theory and experiment has been obtained for a missing-row (or equivalently an 'added- row') reconstruction. Alternative buckled-row and unreconstructed surface models can be excluded. The adsorption of the benzoate species on Cu(110) has been found to occur via the carboxylate group. The molecules occupy short bridge sites with the O atoms being slightly displaced from atop sites and are aligned along the close-packed azimuth. The tilt of the molecule with respect to the surface and the degree to which the surface is relaxed have also been investigated. The adsorption of methyl on Cu(111) was studied using either azomethane or methyl iodide to prepare the surface layers. At saturation coverage the preferred adsorption site is the fcc threefold hollow site, whereas at half saturation coverage ∼ 30 % of the methyl species occupy the hop threefold hollow sites. Best agreement between theory and experiment corresponded to a methyl group adsorbed with C 3v symmetry. The height of the C above the surface in a pure methyl layer was 1.66 ± 0.02 A, but was reduced to 1.62 ± 0.02 A in the presence of co-adsorbed iodine, suggesting that iodine increases the strength of adsorption. Iodine was also found to occupy the fee threefold hollow sites with a Cu-l bondlength of 2.61 ± 0.02 A. (author)

Analysis of local symmetry and impurity location of Cu2+ ions doped C8H11KO8 single crystal through EPR technique for site I

Science.gov (United States)

Sheela, K. Juliet; Subbulakshmi, N.; Subramanian, P.

2018-04-01

Electron paramagnetic resonance (EPR) studies have been investigated on Cu2+ ion incorporated into the single crystals of potassium succinate-succinic acid (KSSA) at room temperature. Two magnetically in-equivalent Cu2+ sites in the lattice are identified, among them site I has been reported. The spin Hamiltonian parameters are determined with the fitting of spectra to rhombic symmetry crystalline field. The co-ordination of the Cu2+ ion in this molecule is a distorted dodecahedron. From the calculated gxx, gyy, gzz and Axx, Ayy, Azz and their directional cosines values, location of site I impurity ion Cu2+ could be identified as a substituitional one. Also the ground state wave function of the impurity ion was found to be d2z.

Analytic observations for the d=1+ 1 bridge site (or single-step) deposition model

International Nuclear Information System (INIS)

Evans, J.W.; Kang, H.C.

1991-01-01

Some exact results for a reversible version of the d=1+1 bridge site (or single-step) deposition model are presented. Exact steady-state properties are determined directly for finite systems with various mean slopes. These show explicitly how the asymptotic growth velocity and fluctuations are quenched as the slope approaches its maximum allowed value. Next, exact hierarchial equations for the dynamics are presented. For the special case of ''equilibrium growth,'' these are analyzed exactly at the pair-correlation level directly for an infinite system. This provided further insight into asymptotic scaling behavior. Finally, the above hierarchy is compared with one generated from a discrete form of the Kardar--Parisi--Zhang equations. Some differences are described

Geochemical Processes Data Package for the Vadose Zone in the Single-Shell Tank Waste Management Areas at the Hanford Site

Energy Technology Data Exchange (ETDEWEB)

Cantrell, Kirk J.; Zachara, John M.; Dresel, P. Evan; Krupka, Kenneth M.; Serne, R. Jeffrey

2007-09-28

This data package discusses the geochemistry of vadose zone sediments beneath the single-shell tank farms at the U.S. Department of Energy’s (DOE’s) Hanford Site. The purpose of the report is to provide a review of the most recent and relevant geochemical process information available for the vadose zone beneath the single-shell tank farms and the Integrated Disposal Facility. Two companion reports to this one were recently published which discuss the geology of the farms (Reidel and Chamness 2007) and groundwater flow and contamination beneath the farms (Horton 2007).

Single-site Lennard-Jones models via polynomial chaos surrogates of Monte Carlo molecular simulation

KAUST Repository

Kadoura, Ahmad Salim

2016-06-01

In this work, two Polynomial Chaos (PC) surrogates were generated to reproduce Monte Carlo (MC) molecular simulation results of the canonical (single-phase) and the NVT-Gibbs (two-phase) ensembles for a system of normalized structureless Lennard-Jones (LJ) particles. The main advantage of such surrogates, once generated, is the capability of accurately computing the needed thermodynamic quantities in a few seconds, thus efficiently replacing the computationally expensive MC molecular simulations. Benefiting from the tremendous computational time reduction, the PC surrogates were used to conduct large-scale optimization in order to propose single-site LJ models for several simple molecules. Experimental data, a set of supercritical isotherms, and part of the two-phase envelope, of several pure components were used for tuning the LJ parameters (ε, σ). Based on the conducted optimization, excellent fit was obtained for different noble gases (Ar, Kr, and Xe) and other small molecules (CH4, N2, and CO). On the other hand, due to the simplicity of the LJ model used, dramatic deviations between simulation and experimental data were observed, especially in the two-phase region, for more complex molecules such as CO2 and C2 H6.

Stability of detectability over 17 years at a single site and other lizard detection comparisons from Guam

Science.gov (United States)

Rodda, Gordon H.; Dean-Bradley, Kathryn; Campbell, Earl W.; Fritts, Thomas H.; Lardner, Bjorn; Yackel Adams, Amy A.; Reed, Robert N.

2015-01-01

To obtain quantitative information about population dynamics from counts of animals, the per capita detectabilities of each species must remain constant over the course of monitoring. We characterized lizard detection constancy for four species over 17 yr from a single site in northern Guam, a relatively benign situation because detection was relatively easy and we were able to hold constant the site, habitat type, species, season, and sampling method. We monitored two species of diurnal terrestrial skinks (Carlia ailanpalai [Curious Skink], Emoia caeruleocauda [Pacific Bluetailed Skink]) using glueboards placed on the ground in the shade for 3 h on rainless mornings, yielding 10,286 skink captures. We additionally monitored two species of nocturnal arboreal geckos (Hemidactylus frenatus [Common House Gecko]; Lepidodactylus lugubris [Mourning Gecko]) on the basis of 15,212 sightings. We compared these count samples to a series of complete censuses we conducted from four or more total removal plots (everything removed to mineral soil) totaling 400 m2(about 1% of study site) in each of the years 1995, 1999, and 2012, providing time-stamped quantification of detectability for each species. Unfortunately, the actual population trajectories taken by the four species were masked by unexplained variation in detectability. This observation of debilitating latent variability in lizard detectability under nearly ideal conditions undercuts our trust in population estimation techniques that fail to quantify venue-specific detectability, rely on pooled detection probability estimates, or assume that modulation in predefined environmental covariates suffices for estimating detectability.

Production of propylene from 1-butene on highly active "bi-functional single active site" catalyst: Tungsten carbene-hydride supported on alumina

KAUST Repository

Mazoyer, Etienne; Szeto, Kaï Chung; Norsic, Sé bastien; Garron, Anthony; Basset, Jean-Marie; Nicholas, Christopher P.; Taoufik, Mostafa

2011-01-01

1-Butene is transformed in a continuous flow reactor over tungsten hydrides precursor W-H/Al2O3, 1, giving a promising yield into propylene at 150 °C and different pressures. Tungsten carbene-hydride single active site operates as a "bi

Site Selection for the Salt Disposition Facility at the Savannah River Site

International Nuclear Information System (INIS)

Gladden, J.B.; Rueter, K.J.; Morin, J.P.

2000-01-01

A site selection study was conducted to identify a suitable location for the construction and operation of a new Salt Disposition Facility (SDF) at the Savannah River Site (SRS). The facility to be sited is a single processing facility and support buildings that could house either of three technology alternatives being developed by the High Level Waste Systems Engineering Team: Small Tank Tetraphenylborate Precipitation, Crystalline Silicotitanate Non-Elutable Ion Exchange or Caustic Side Solvent Extraction. A fourth alternative, Direct Disposal in grout, is not part of the site selection study because a location has been identified that is unique to this technology (i.e., Z-Area). Facility site selection at SRS is a formal, documented process that seeks to optimize siting of new facilities with respect to facility-specific engineering requirements, sensitive environmental resources, and applicable regulatory requirements. In this manner, the prime objectives of cost minimization, environmental protection, and regulatory compliance are achieved. The results from this geotechnical characterization indicated that continued consideration be given to Site B for the proposed SDF. Suitable topography, the lack of surface hydrology and floodplain issues, no significant groundwater contamination, the presence of minor soft zones along the northeast portion of footprint, and no apparent geological structure in the Gordon Aquitard support this recommendation

Overview of the closure approach for the Hanford Site single-shell tank farm

International Nuclear Information System (INIS)

Smith, E.H.

1991-09-01

The disposal of chemical and radioactive waste stored within the single-shell tanks (SST) represents one of the most significant waste management problems at the Hanford Site. A comprehensive program has been established to obtain analytical data regarding the chemical and radiological constituents within these tanks. This information will be used to support the development of a supplemental environmental impact statement (SEIS) and ultimately to aid in the selection of a final disposal option. This paper discusses some of the technical options and major regulatory issues associated with SST waste retrieval and in situ waste treatment and disposal. Certain closure options and treatment technologies will require further development before they can be implemented or accepted as being useful. In addition, continued negotiations with the regulatory authorities will be required to determine the preferred closure option and the regulatory pathway to accommodate such closure

Site characterization studies in the NWTS program

International Nuclear Information System (INIS)

Shipler, D.; Evans, G.

1980-01-01

The US Department of Energy (DOE) has the responsibility to identify sites and construct and operate facilities for the storage or isolation of spent fuel and/or reprocessing radioactive wastes from commercial nuclear power plants. The National Waste Terminal Storage (NWTS) Program has been initiated by the DOE to develop the technology and demonstrate the feasibility of burial and isolation of high level radioactive waste in deep geologic formations. The NTWS Program plan which sets forth the criteria, procedures, and other considerations required to characterize and select a site in a comprehensive stepwise manner is discussed. The plan is not specific to any given geologic medium but serves as a guide for site selection in any geohydrologic system deemed appropriate for consideration for a deep geologic repository. The plan will be used by all NWTS Project Offices in the conduct of their site characterization program. The plan will be updated, as warranted, to reflect technology development, National policies, rulemakings by regulatory agencies, and other changing political, social, and institutional considerations. Site characterization begins with the identification of regions believed to have suitable geologic, hydrologic, and environmental characteristics for repository siting. This is followed by an iterative process of data collection and analysis to identify areas and locations which appear most suitable for further investigations. In addition, screening studies of the DOE's nuclear complexes has led to the selection of the Nevada Test Site and the Hanford Site for further characterization studies. The site characterization process results in a number of candidate sites from which a site will be selected and proposed to the NRC for licensing

The learning curve of laparoendoscopic single-site (LESS) cholecystectomy: definable, short, and safe.

Science.gov (United States)

Hernandez, Jonathan; Ross, Sharona; Morton, Connor; McFarlin, Kellie; Dahal, Sujat; Golkar, Farhaad; Albrink, Michael; Rosemurgy, Alexander

2010-11-01

The applications of laparoendoscopic single-site (LESS) surgery, including cholecystectomy, are occurring quickly, although little is generally known about issues associated with the learning curve of this new technique including operative time, conversion rates, and safety. We prospectively followed all patients undergoing LESS cholecystectomy, and compared operations undertaken at our institutions in cohorts of 25 patients with respect to operative times, conversion rates, and complications. One-hundred fifty patients of mean age 46 years underwent LESS cholecystectomy. No significant differences in operative times were demonstrable between any of the 25-patient cohorts operated on at our institution. A significant reduction in operative times (p < 0.001) after completion of 75 LESS procedures was, however, identified with the experience of a single surgeon. No significant reduction in the number of procedures requiring an additional trocar(s) or conversion to open operations was observed after completion of 25 LESS cholecystectomies. Complication rates were low, and not significantly different between any 25-patient cohorts. For surgeons proficient with multi-incision laparoscopic cholecystectomy, the learning curve for LESS cholecystectomy begins near proficiency. Operative complications and conversions were infrequent and unchanged across successive 25-patient cohorts, and were similar to those reported for multi-incision laparoscopic cholecystectomy after the learning curve. Copyright © 2010 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Laparoendoscopic single-site surgery in gynaecology: A new frontier in minimally invasive surgery

Directory of Open Access Journals (Sweden)

Fader Amanda

2011-01-01

Full Text Available Review Objective: To review the recent developments and published literature on laparoendoscopic single-site (LESS surgery in gynaecology. Recent Findings: Minimally invasive surgery has become a standard of care for the treatment of many benign and malignant gynaecological conditions. Recent advances in conventional laparoscopy and robotic-assisted surgery have favorably impacted the entire spectrum of gynaecological surgery. With the goal of improving morbidity and cosmesis, continued efforts towards refinement of laparoscopic techniques have lead to minimization of size and number of ports required for these procedures. LESS surgery is a recently proposed surgical term used to describe various techniques that aim at performing laparoscopic surgery through a single, small-skin incision concealed within the umbilicus. In the last 5 years, there has been a surge in the developments in surgical technology and techniques for LESS surgery, which have resulted in a significant increase in utilisation of LESS across many surgical subspecialties. Recently published outcomes data demonstrate feasibility, safety and reproducibility for LESS in gynaecology. The contemporary LESS literature, extent of gynaecological procedures utilising these techniques and limitations of current technology will be reviewed in this manuscript. Conclusions: LESS surgery represents the newest frontier in minimally invasive surgery. Comparative data and prospective trials are necessary in order to determine the clinical impact of LESS in treatment of gynaecological conditions.

Ecological and radioecological studies of nuclear installation sites

International Nuclear Information System (INIS)

Caries, J. C.; Hugon, J.; Grauby, A.

1988-01-01

The site study method consists of a dynamic and estimated analysis and of following up the release impact on all natural or non natural media compartments that take a part in the protection of man and his environment. The stages of knowing a nuclear site include the site preliminary radioecological evaluation, diffusion parameters evaluation, the quantification of factors of radioelements transfer to man, the ecological baseline carrying out, the radioactive baseline establishment, the radioecological synthesis of the results, the site radioactive and ecological control. This method applys to selection and detailed study of site. 1 tab., 7 refs. (F.M.)

S1-sensitive sites in DNA after γ-irradiation

International Nuclear Information System (INIS)

Martin-Bertram, H.

1981-01-01

DNA from γ-irradiated T 1 bacteriophages was analyzed for 'single-stranded' sites by cleavage with S1 nuclease from Aspergillus oryzae as lesion probe. The ratio of 'S1-sensitive sites' to the amount of radiation-induced single-strand breaks was about one. Presumably these 'denatured' sites were associated with single-strand breaks. The subsequent check for the persistence of 'single-stranded' sites within the DNA molecule by thermokinetics demonstrated a strong affinity of the nuclease to its substrate, the single-stranded lesion, and a perfect excision. It is assumed that the direct absorption of radiation energy in the DNA gives rise to the formation of such bulky lesions. (Auth.)

Sternoe study site. Scope of activities and main results

International Nuclear Information System (INIS)

Ahlbom, K.; Andersson, J.E.; Nordqvist, R.; Tiren, S.; Ljunggren, C.; Voss, C.

1992-01-01

During the period from 1977-1986 SKB (Swedish Nuclear Fuel and Waste Management Co) performed surface and borehole investigations of 14 study sites for the purpose of assessing their suitability for a repository of spent nuclear fuel. The next phase in the SKB site selection programme will be to perform detailed characterization, including characterization from shafts and/or tunnels, of two or three sites. The detailed investigations will continue over several years to provide all the data needed for a licensing application to build a repository. Such an application is foreseen to be given to the authorities around the year 2003. It is presently not clear if anyone of the previously investigated study sites will be selected as a site for detailed characterization. Other sites with geological and/or socio-economical characteristics judged more favourable may very well be the ones selected. However, as a part of the background documentation needed for the site selection studies to come, summary reports will be prepared for most study sites. These reports will include scope of activities, main results, uncertainties and need of complementary investigations. This report concerns the Sternoe study site. This site was one of the first sites to be investigated by SKB . The studies at Sternoe were made under severe time-constraints and with prototype borehole instrumentations. These limitations should be kept in mind when reading the report. (41 refs., 16 figs., 12 tabs.) (au)

Gideaa study site. Scope of activities and main results

International Nuclear Information System (INIS)

Ahlbom, K.; Andersson, J.E.; Nordqvist, R.; Ljunggren, C.; Tiren, S.; Voss, C.

1991-10-01

During the period from 1977-1986 SKB (Swedish Nuclear Fuel and Waste Management Co) performed surface and borehole investigations of 14 study sites for the purpose of assessing their suitability for a repository of spent nuclear fuel. The next phase in the SKB site selection programme will be to perform detailed characterization, including characterization from shafts and/or tunnels, of two or three sites. The detailed investigations will continue over several years to provide all the data needed for a licensing application to build a repository. Such an application is foreseen to be given to the authorities around the year 2003. It is presently not clear if anyone of the study sites will be selected as a site for detailed characterization. Other site with geological and/or socio-economical characteristics judged more favourable may very well be the ones selected. However, as a part of the background documentation needed for the site selection studies to come, summary reports will be prepared for most study sites. These reports will include scope of activities, main results, uncertainties and need of complementary investigations. This report concerns the Gideaa study site. (au)

Kamlunge study site. Scope of activities and main results

International Nuclear Information System (INIS)

Ahlbom, K.; Andersson, J.E.; Andersson, P.; Ittner, T.; Tiren, S.; Ljunggren, C.

1992-05-01

During the period from 1977-1986 SKB (Swedish nuclear Fuel and Waste Management Co.) performed surface and borehole investigations of 14 study sites for the purpose of assessing their suitability for a repository of spent nuclear fuel. The next phase in the SKB site selection programme will be to perform detailed characterization, including characterization from shafts and/or tunnels, of two or three sites. The detailed investigations will continue over several years to provide all the data needed for a licensing application to build a repository. Such an application is foreseen to be given to the authorities around the year 2003. It is presently not clear if anyone of the study sites will be selected as a site for detailed characterization. Other sites with geological and/or socio-economical characteristics judged more favourable may very well be selected. However, as a part of the background documentation needed for the site selection studies to come, summary reports will be prepared for most study sites. These reports will include scope of activities, main results, uncertainties and need of complementary investigations. This report concerns the Kamlunge study site. (79 refs.) (au)

Fjaellveden study site. Scope of activities and main results

International Nuclear Information System (INIS)

Ahlbom, K.; Andersson, J.E.; Nordqvist, R.; Ljunggren, C.; Tiren, S.; Voss, C.

1991-10-01

During the period from 1977-1986 SKB (Swedish Nuclear Fuel and Waste Management CO) performed surface and borehole investigations of 14 study sites for the purpose of assessing their suitability for a repository of spent nuclear fuel. The next phase in the SKB site selection programme will be to perform detailed characterization, including characterization from shafts and/or tunnels, of two or three sites. The detailed investigations will continue over several years to provide all the data needed for a licensing application to build repository. Such an application is foreseen to be given to the authorities around the year 2003. It is presently not clear if anyone of the study sites will be selected as a site for detailed characterization. Other sites with geological and/or socio-economical characteristics judged more favourable may very well be the ones selected. However, as a part of the background documentation needed for the site selection studies to come, summary reports will be prepared for most study sites. These reports will include scope of activities, main results, uncertainties and need for complementary investigations. This report concerns the Fjaellveden study site. (au)

Substantial differences in bias between single-digest and double-digest RAD-seq libraries: A case study.

Science.gov (United States)

Flanagan, Sarah P; Jones, Adam G

2018-03-01

The trade-offs of using single-digest vs. double-digest restriction site-associated DNA sequencing (RAD-seq) protocols have been widely discussed. However, no direct empirical comparisons of the two methods have been conducted. Here, we sampled a single population of Gulf pipefish (Syngnathus scovelli) and genotyped 444 individuals using RAD-seq. Sixty individuals were subjected to single-digest RAD-seq (sdRAD-seq), and the remaining 384 individuals were genotyped using a double-digest RAD-seq (ddRAD-seq) protocol. We analysed the resulting Illumina sequencing data and compared the two genotyping methods when reads were analysed either together or separately. Coverage statistics, observed heterozygosity, and allele frequencies differed significantly between the two protocols, as did the results of selection components analysis. We also performed an in silico digestion of the Gulf pipefish genome and modelled five major sources of bias: PCR duplicates, polymorphic restriction sites, shearing bias, asymmetric sampling (i.e., genotyping fewer individuals with sdRAD-seq than with ddRAD-seq) and higher major allele frequencies. This combination of approaches allowed us to determine that polymorphic restriction sites, an asymmetric sampling scheme, mean allele frequencies and to some extent PCR duplicates all contribute to different estimates of allele frequencies between samples genotyped using sdRAD-seq versus ddRAD-seq. Our finding that sdRAD-seq and ddRAD-seq can result in different allele frequencies has implications for comparisons across studies and techniques that endeavour to identify genomewide signatures of evolutionary processes in natural populations. © 2017 John Wiley & Sons Ltd.

Single atom self-diffusion on nickel surfaces

International Nuclear Information System (INIS)

Tung, R.T.; Graham, W.R.

1980-01-01

Results of a field ion microscope study of single atom self-diffusion on Ni(311), (331), (110), (111) and (100) planes are presented, including detailed information on the self-diffusion parameters on (311), (331), and (110) surfaces, and activation energies for diffusion on the (111), and (100) surfaces. Evidence is presented for the existence of two types of adsorption site and surface site geometry for single nickel atoms on the (111) surface. The presence of adsorbed hydrogen on the (110), (311), and (331) surfaces is shown to lower the onset temperature for self-diffusion on these planes. (orig.)

The use of modern dressings in managing split-thickness skin graft donor sites: a single-centre randomised controlled trial.

Science.gov (United States)

Kazanavičius, M; Cepas, A; Kolaityte, V; Simoliuniene, R; Rimdeika, R

2017-06-02

To identify the most appropriate, most suitable and most efficient dressing for split-thickness skin graft (STSG) donor sites. Comparing the wound healing rate, pain severity and duration, as well as the dressing change frequency in four randomised patient groups. A single-centre non-blinded randomised controlled trial was carried out during 2010-2014. All patients treated for skin defects/lesions (due to burns, trauma or ulcers) using STSG were included in the study. All patients were randomly allocated in four different donor site treatment groups; polyurethane (PU group, Mepilex); polyurethane with silicone membrane (PUSM group; Mepilex border,); transparent, breathable film (TBF group; Mepitel film) and cotton gauze dressings (CG group) using Excel 2007. We evaluated: wound healing time, pain severity and duration, the frequency of dressing change, donor site re-epithelialisation, donor site complications (signs of inflammation or infection). Patients were assessed on postoperative days: 1, 3, 6, 9, 12, 15, 18 and 21. After random allocation of study participants the number of patients in each group were: PU group n=25; PUSM group n=24; TBF group n=24; CG group n=25. The groups were homogenous according to gender, age, main pathology, donor site area and wound size. The STSG donor site healing time varied from 9 to 21 days. The mean healing time in the CG group was 14.76 days, whereas in the PU, PUSM, and TBF group it was significantly shorter; 12.25 days, 11.63 days and 10 days, respectively. Patients in the TBF group demonstrated the most rapid healing time with 66.7% of STSG donor sites healed by postoperative day 9. The pain duration interval in modern dressing groups (PU, PUSM and TBF groups) was 0-9 days, whereas it was 6-18 day in the CS group. Pain intensity mean on postoperative day 1 was 2.21 in the PU group; 1.67 in the PUSM group; 1.46 in the TBF group and 3.04 in the CG group. The average pain duration in Group PU, PUSM, and TBF was 4.08 days; 2

Engineering Single-Atom Cobalt Catalysts toward Improved Electrocatalysis.

Science.gov (United States)

Wan, Gang; Yu, Pengfei; Chen, Hangrong; Wen, Jianguo; Sun, Cheng-Jun; Zhou, Hua; Zhang, Nian; Li, Qianru; Zhao, Wanpeng; Xie, Bing; Li, Tao; Shi, Jianlin

2018-04-01

The development of cost-effective catalysts to replace noble metal is attracting increasing interests in many fields of catalysis and energy, and intensive efforts are focused on the integration of transition-metal sites in carbon as noble-metal-free candidates. Recently, the discovery of single-atom dispersed catalyst (SAC) provides a new frontier in heterogeneous catalysis. However, the electrocatalytic application of SAC is still subject to several theoretical and experimental limitations. Further advances depend on a better design of SAC through optimizing its interaction with adsorbates during catalysis. Here, distinctive from previous studies, favorable 3d electronic occupation and enhanced metal-adsorbates interactions in single-atom centers via the construction of nonplanar coordination is achieved, which is confirmed by advanced X-ray spectroscopic and electrochemical studies. The as-designed atomically dispersed cobalt sites within nonplanar coordination show significantly improved catalytic activity and selectivity toward the oxygen reduction reaction, approaching the benchmark Pt-based catalysts. More importantly, the illustration of the active sites in SAC indicates metal-natured catalytic sites and a media-dependent catalytic pathway. Achieving structural and electronic engineering on SAC that promotes its catalytic performances provides a paradigm to bridge the gap between single-atom catalysts design and electrocatalytic applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Identification of single-shell tank in-tank hardware obstructions to retrieval at Hanford Site Tank Farms

International Nuclear Information System (INIS)

Ballou, R.A.

1994-10-01

Two retrieval technologies, one of which uses robot-deployed end effectors, will be demonstrated on the first single-shell tank (SST) waste to be retrieved at the Hanford Site. A significant impediment to the success of this technology in completing the Hanford retrieval mission is the presence of unique tank contents called in-tank hardware (ITH). In-tank hardware includes installed and discarded equipment and various other materials introduced into the tank. This paper identifies those items of ITH that will most influence retrieval operations in the arm-based demonstration project and in follow-on tank operations within the SST farms

Finnsjoen study site. Scope of activities and main results

International Nuclear Information System (INIS)

Ahlbom, K.; Andersson, J.E.; Andersson, Peter; Ittner, T.; Tiren, S.; Ljunggren, C.

1992-12-01

The Finnsjoen study site was selected in 1977 to provide input to the KBS-1 and KBS-2 performance assessments. The site was later used as a test site for testing new instruments and new site characterization methods, as well as a research site for studying mainly groundwater flow and groundwater transport. All together, the Finnsjoen studies have involved 11 cored boreholes, down to max 700 m depth, and extensive borehole geophysical, geochemical and geohydraulic measurements, as well as rock stress measurements and tracer tests. This report presents the scope of the Finnsjoen studies together with main results. Conceptual uncertainties in assumptions and models are discussed with emphasis on the models used for the performance assessment SKB91. Of special interest for the Finnsjoen study site is the strong influence caused by a subhorizontal fracture zone on groundwater flow, transport and chemistry

Single-site Lennard-Jones models via polynomial chaos surrogates of Monte Carlo molecular simulation

Energy Technology Data Exchange (ETDEWEB)

Kadoura, Ahmad, E-mail: ahmad.kadoura@kaust.edu.sa, E-mail: adil.siripatana@kaust.edu.sa, E-mail: shuyu.sun@kaust.edu.sa, E-mail: omar.knio@kaust.edu.sa; Sun, Shuyu, E-mail: ahmad.kadoura@kaust.edu.sa, E-mail: adil.siripatana@kaust.edu.sa, E-mail: shuyu.sun@kaust.edu.sa, E-mail: omar.knio@kaust.edu.sa [Computational Transport Phenomena Laboratory, The Earth Sciences and Engineering Department, The Physical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900 (Saudi Arabia); Siripatana, Adil, E-mail: ahmad.kadoura@kaust.edu.sa, E-mail: adil.siripatana@kaust.edu.sa, E-mail: shuyu.sun@kaust.edu.sa, E-mail: omar.knio@kaust.edu.sa; Hoteit, Ibrahim, E-mail: ibrahim.hoteit@kaust.edu.sa [Earth Fluid Modeling and Predicting Group, The Earth Sciences and Engineering Department, The Physical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900 (Saudi Arabia); Knio, Omar, E-mail: ahmad.kadoura@kaust.edu.sa, E-mail: adil.siripatana@kaust.edu.sa, E-mail: shuyu.sun@kaust.edu.sa, E-mail: omar.knio@kaust.edu.sa [Uncertainty Quantification Center, The Applied Mathematics and Computational Science Department, The Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900 (Saudi Arabia)

2016-06-07

In this work, two Polynomial Chaos (PC) surrogates were generated to reproduce Monte Carlo (MC) molecular simulation results of the canonical (single-phase) and the NVT-Gibbs (two-phase) ensembles for a system of normalized structureless Lennard-Jones (LJ) particles. The main advantage of such surrogates, once generated, is the capability of accurately computing the needed thermodynamic quantities in a few seconds, thus efficiently replacing the computationally expensive MC molecular simulations. Benefiting from the tremendous computational time reduction, the PC surrogates were used to conduct large-scale optimization in order to propose single-site LJ models for several simple molecules. Experimental data, a set of supercritical isotherms, and part of the two-phase envelope, of several pure components were used for tuning the LJ parameters (ε, σ). Based on the conducted optimization, excellent fit was obtained for different noble gases (Ar, Kr, and Xe) and other small molecules (CH{sub 4}, N{sub 2}, and CO). On the other hand, due to the simplicity of the LJ model used, dramatic deviations between simulation and experimental data were observed, especially in the two-phase region, for more complex molecules such as CO{sub 2} and C{sub 2} H{sub 6}.

Klipperaas study site. Scope of activities and main results

International Nuclear Information System (INIS)

Ahlbom, K.; Andersson, J.E.; Andersson, Peter; Ittner, T.; Tiren, S.; Ljunggren, C.

1992-09-01

During the period from 1977 - 1986 SKB (Swedish Nuclear Fuel and Waste Management Co.) performed surface and borehole investigations of 14 study sites for the purpose of assessing their suitability for a repository of spent nuclear fuel. The next phase in the SKB site selection rpogramme will be to perform detailed characterisation, including characterization from shafts and/or tunnels, of two or three sites. The detailed investigations will continue over several years to provide all the data needed for a licensing application to build a repository. Such an application is foreseen to be given to the authorities around the year 2003. It is presently not clear if any of the study sites will be selected as a site for detailed characterization. Other sites with geological and/or socio-economical characteristics judged more favorable may very well be the ones selected. However, as a part of the background documentation needed for the site selection studies to come, summary reports will be prepared for most study sites. These reports will include scope of activities, main results, uncertainties and need of complementary investigations. This report concern the Klipperaas study site. The main topics are the scope of activities, geologic model, geohydrological model, groundwater chemistry, assessment of solute transport, and rock mechanics

Site-resolved neutralization of slow singly and multiply charged ions during large-angle backscattering collisions with RbI(1 0 0)

CERN Document Server

Meyer, F W; Vane, C R

2003-01-01

Preliminary results are reported of projectile neutralization during 120 deg. backscattering from RbI[1 0 0] of singly and multiply charged incident ions in the keV energy range. Scattered charge fractions are reported for 4.4 keV Ne sup 8 sup + and 4.2 keV F sup + normally incident on the ionic crystal. Collisions associated with scattering from a Rb or I site can be clearly distinguished for each scattered final charge state. Significant differences are observed in the intensities of the higher scattered charge states resulting from collisions with Rb and I sites. In contrast, at the target azimuth orientation of the present measurement, only minor differences in F sup - yield are observed for hard scattering from the two lattice sites.

Well-Defined Silica Supported Aluminum Hydride: Another Step Towards the Utopian Single Site Dream?

KAUST Repository

Werghi, Baraa; Bendjeriou-Sedjerari, Anissa; Sofack-Kreutzer, Julien; Jedidi, Abdesslem; Abou-Hamad, Edy; Cavallo, Luigi; Basset, Jean-Marie

2015-01-01

Reaction of triisobutylaluminum with SBA15700 at room temperature occurs by two parallel pathways involving either silanol or siloxane bridges. It leads to the formation of a well-defined bipodal [(≡SiO)2Al-CH2CH(CH3)2] 1a, silicon isobutyl [≡Si-CH2CH(CH3)2] 1b and a silicon hydride [≡Si-H] 1c. Their structural identity was characterized by FT-IR and advance solid-state NMR spectroscopies (1H, 13C, 29Si, 27Al and 2D multiple quantum), elemental and gas phase analysis, and DFT calculations. The reaction involves the formation of a highly reactive monopodal intermediate: [≡SiO-Al-[CH2CH(CH3)2]2], with evolution of isobutane. This intermediate undergoes two parallel routes: Transfer of either one isobutyl fragment or of one hydride to an adjacent silicon atom. Both processes occur by opening of a strained siloxane bridge, ≡Si-O-Si≡ but with two different mechanisms, showing that the reality of “single site” catalyst may be an utopia: DFT calculations indicate that isobutyl transfer occurs via a simple metathesis between the Al-isobutyl and O-Si bonds, while hydride transfer occurs via a two steps mechanism, the first one is a ß-H elimination to Al with elimination of isobutene, whereas the second is a metathesis step between the formed Al-H bond and a O-Si bond. Thermal treatment of 1a (at 250 °C) under high vacuum (10-5 mbar) generates Al-H through a ß-H elimination of isobutyl fragment. These supported well-defined Al-H which are highly stable with time, are tetra, penta and octa coordinated as demonstrated by IR and 27Al–1H J-HMQC NMR spectroscopy. All these observations indicate that surfaces atoms around the site of grafting play a considerable role in the reactivity of a single site system.

Well-Defined Silica Supported Aluminum Hydride: Another Step Towards the Utopian Single Site Dream?

KAUST Repository

Werghi, Baraa

2015-07-17

Reaction of triisobutylaluminum with SBA15700 at room temperature occurs by two parallel pathways involving either silanol or siloxane bridges. It leads to the formation of a well-defined bipodal [(≡SiO)2Al-CH2CH(CH3)2] 1a, silicon isobutyl [≡Si-CH2CH(CH3)2] 1b and a silicon hydride [≡Si-H] 1c. Their structural identity was characterized by FT-IR and advance solid-state NMR spectroscopies (1H, 13C, 29Si, 27Al and 2D multiple quantum), elemental and gas phase analysis, and DFT calculations. The reaction involves the formation of a highly reactive monopodal intermediate: [≡SiO-Al-[CH2CH(CH3)2]2], with evolution of isobutane. This intermediate undergoes two parallel routes: Transfer of either one isobutyl fragment or of one hydride to an adjacent silicon atom. Both processes occur by opening of a strained siloxane bridge, ≡Si-O-Si≡ but with two different mechanisms, showing that the reality of “single site” catalyst may be an utopia: DFT calculations indicate that isobutyl transfer occurs via a simple metathesis between the Al-isobutyl and O-Si bonds, while hydride transfer occurs via a two steps mechanism, the first one is a ß-H elimination to Al with elimination of isobutene, whereas the second is a metathesis step between the formed Al-H bond and a O-Si bond. Thermal treatment of 1a (at 250 °C) under high vacuum (10-5 mbar) generates Al-H through a ß-H elimination of isobutyl fragment. These supported well-defined Al-H which are highly stable with time, are tetra, penta and octa coordinated as demonstrated by IR and 27Al–1H J-HMQC NMR spectroscopy. All these observations indicate that surfaces atoms around the site of grafting play a considerable role in the reactivity of a single site system.

Spontaneous Ag-Nanoparticle Growth at Single-Walled Carbon Nanotube Defect Sites: A Tool for In Situ Generation of SERS Substrate

Directory of Open Access Journals (Sweden)

Jason Maley

2011-01-01

Full Text Available Silver nanoparticles were spontaneously formed on pristine and oxidized single-wall nanotubes. Nanoparticles were observed on carbon nanotubes with AFM, and the presence of Ag nanoparticles were confirmed by ESR experiments. Raman spectroscopy of the Ag-treated carbon nanotubes had a 4–10X enhancement of intensity compared to untreated carbon nanotubes. Ag nanoparticles formed at defect sites on the CNT surface, where free electrons located at the defect sites reduced Ag+ to Ag. A mechanism for the propagation of the nanoparticles is through a continual negative charge generation on the nanoparticle by electron transfer from doublet oxygen (O2−.

Nuclear Energy Center study. Phase II. Site suitability analysis. Final report

International Nuclear Information System (INIS)

Fellows, W.S.; Sharp, J.M.; Benator, B.I.

1978-06-01

A site screening study was conducted to identify a site or sites for detailed, site-specific study as a nuclear energy center. Using technical criteria of water requirements, geotechnical constraints, and projected load center and transmission considerations as well as environmental and institutional considerations, five potential study sites in the State of South Carolina were identified, evaluated against established criteria, and ranked according to their acceptability as potential nuclear energy center study sites. Consideration of what is ''representative'' of a site as well as the ranking score was factored into site recommendations, since the site deemed easiest to license and permit may not be the most desirable site for future study of the technical and institutional feasibility and practicality of a specific site. The sites near Lake Hartwell and the Savannah River Plant (SRP) of the Department of Energy were selected as potential study sites after consideration of the above criteria. Because the Lake Hartwell site offers the opportunity to consider institutional issues which may be more representative of other possible NEC sites, it is recommended that the Lake Hartwell site be studied to establish the feasibility and practicality of the nuclear energy concept on a site-specific basis

Thermal evaluation by infrared measurement of implant site preparation between single and gradual drilling in artificial bone blocks of different densities.

Science.gov (United States)

Möhlhenrich, S C; Abouridouane, M; Heussen, N; Hölzle, F; Klocke, F; Modabber, A

2016-11-01

The aim of this study was to investigate the influence of bone density and drilling protocol on heat generation during implant bed preparation. Ten single and 10 gradual implant sites with diameters of 2.8, 3.5, and 4.2mm were prepared in four artificial bone blocks (density types I-IV; D1-D4). Drilling was done at constant speed (1500rpm) and with external irrigation (50ml/min); vertical speed was set at 2mm/s. An infrared camera was used for temperature measurements. Significantly higher temperatures for single drilling were found between 2.8-mm drills in D1 (P=0.0014) and D4 (P<0.0001) and between 3.5-mm drills in D3 (P=0.0087) and D4 (P<0.0001), as well as between 4.2-mm drills in D1 (P<0.0001) and D4 (P=0.0014). Low bone density led to a thermal decrease after single drilling and a thermal increase after gradual drilling. Burs with a large diameter always showed a higher temperature generation. In comparisons between 2.8- and 4.2-mm diameters for both single and gradual drills, significant differences (P<0.001) were noted for bone types II, III, and IV. Single drilling could generate more heat than traditional sequential drilling, and bone density, as well as drill diameter, influenced thermal increases. Particularly in lower-density bone, conventional sequential drilling seems to raise the temperature less. Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Preliminary recommendations on the design of the characterization program for the Hanford Site single-shell tanks: A system analysis

International Nuclear Information System (INIS)

Buck, J.W.; Peffers, M.S.; Hwang, S.T.

1991-11-01

The work described in this volume was conducted by Pacific Northwest Laboratory to provide preliminary recommendations on data quality objectives (DQOs) to support the Waste Characterization Plan (WCP) and closure decisions for the Hanford Site single-shell tanks (SSTs). The WCP describes the first of a two-phase characterization program that will obtain information to assess and implement disposal options for SSTs. This work was performed for the Westinghouse Hanford Company (WHC), the current operating contractor on the Hanford Site. The preliminary DQOs contained in this volume deal with the analysis of SST wastes in support of the WCP and final closure decisions. These DQOs include information on significant contributors and detection limit goals (DLGs) for SST analytes based on public health risk

Nuclear Energy Center study. Phase II. Site suitability analysis. Final report

Energy Technology Data Exchange (ETDEWEB)

Fellows, W.S.; Sharp, J.M.; Benator, B.I.

1978-06-01

A site screening study was conducted to identify a site or sites for detailed, site-specific study as a nuclear energy center. Using technical criteria of water requirements, geotechnical constraints, and projected load center and transmission considerations as well as environmental and institutional considerations, five potential study sites in the State of South Carolina were identified, evaluated against established criteria, and ranked according to their acceptability as potential nuclear energy center study sites. Consideration of what is ''representative'' of a site as well as the ranking score was factored into site recommendations, since the site deemed easiest to license and permit may not be the most desirable site for future study of the technical and institutional feasibility and practicality of a specific site. The sites near Lake Hartwell and the Savannah River Plant (SRP) of the Department of Energy were selected as potential study sites after consideration of the above criteria. Because the Lake Hartwell site offers the opportunity to consider institutional issues which may be more representative of other possible NEC sites, it is recommended that the Lake Hartwell site be studied to establish the feasibility and practicality of the nuclear energy concept on a site-specific basis.

Universal Access in Heritage Sites: A Case Study on Historic Sites in Jaipur, India.

Science.gov (United States)

Vardia, Shweta; Khare, Rachna; Khare, Ajay

2016-01-01

A nation is recognized by a range of its significant historical, cultural and natural properties. These properties are generally preserved and maintained either by national administration or by private owners and charitable trusts due to higher value of their cultural inheritance and termed globally as heritage or historic sites. Heritage sites are a significant asset, a unique and irreplaceable resource which reflects a rich and diverse expression of past societies and forms an integral part of local, regional and national cultural identity. Today, heritage sites also play an important role in communication and knowledge exchange. Thus the rapidly increasing heritage tourism industry faces several challenges too. One of the challenges is that there is a segment of society who is not yet able to equally enjoy the visit to historic structures/sites and attractions, facilities and services. This paper aims to study the experience and develop understanding regarding the heritage structures/sites approached and interacted by diverse users. This study is an outcome of a hands on workshop conducted with diverse users at various historic sites in the city of Jaipur viz. at The City Palace Complex, Jaipur, Jaigarh Fort and the Haveli at Kanota near to Jaipur India.

Single-photon double and triple ionization of acetaldehyde (ethanal) studied by multi-electron coincidence spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Zagorodskikh, S. [Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden); Department of Physics, University of Gothenburg, Origovägen 6B, SE-412 96 Gothenburg (Sweden); Zhaunerchyk, V. [Department of Physics, University of Gothenburg, Origovägen 6B, SE-412 96 Gothenburg (Sweden); Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden); Mucke, M. [Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden); Eland, J.H.D. [Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QZ (United Kingdom); Department of Physics, University of Gothenburg, Origovägen 6B, SE-412 96 Gothenburg (Sweden); Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden); Squibb, R.J. [Department of Physics, University of Gothenburg, Origovägen 6B, SE-412 96 Gothenburg (Sweden); Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden); Karlsson, L. [Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden); Linusson, P. [Department of Physics, Stockholm University, AlbaNova University Center, SE-106 91 Stockholm (Sweden); Feifel, R., E-mail: raimund.feifel@gu.se [Department of Physics, University of Gothenburg, Origovägen 6B, SE-412 96 Gothenburg (Sweden); Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden)

2015-12-16

Highlights: • The first ever valence double ionization spectrum of acetaldehyde is reported. • The first ever site-selectively extracted Auger spectra of acetaldehyde are reported. • The first ever Auger spectra of acetaldehyde involving shake-up states are reported. • The first ever triple ionization spectra of acetaldehyde are reported. • The first ever energy sharing of electron pairs emitted by acetaldehyde is presented. - Abstract: Single-photon multiple ionization processes of acetaldehyde (ethanal) have been experimentally investigated by utilizing a multi-particle coincidence technique based on the time-of-flight magnetic bottle principle, in combination with either a synchrotron radiation source or a pulsed helium discharge lamp. The processes investigated include double and triple ionization in the valence region as well as single and double Auger decay of core-ionized acetaldehyde. The latter are studied site-selectively for chemically different carbon core vacancies, scrutinizing early theoretical predictions specifically made for the case of acetaldehyde. Moreover, Auger processes in shake-up and core-valence ionized states are investigated. In the cases where the processes involve simultaneous emission of two electrons, the distributions of the energy sharing are presented, emphasizing either the knock-out or shake-off mechanism.

Single-site SBA-15 supported zirconium catalysts. Synthesis, characterization and toward cyanosilylation reaction

Science.gov (United States)

Xu, Wei; Yu, Bo; Zhang, Ying; Chen, Xi; Zhang, Guofang; Gao, Ziwei

2015-01-01

A successive anchoring of Zr(NMe2)4, cyclopentadiene and a O-donor ligand, 1-hydroxyethylbenzene (PEA), 1,1‧-bi-2-naphthol (Binol) or 2,3-dihydroxybutanedioic acid diethyl ester (Tartrate), on dehydroxylated SBA-15 pretreated at 500 °C for 16 h (SBA-15-500) was conducted by SOMC strategy in moderate conditions. The dehydoxylation of SBA-15 was monitored by in situ Fourier transform infrared spectroscopy (in situ FT-IR). The ligand-modified SBA-15-500 supported zirconium complexes were characterized by in situ FT-IR, 13C CP MAS-NMR, X-ray photoelectron spectroscopy (XPS), inductively coupled plasma mass spectrometry (ICP-MAS) and elemental analysis in detail, verifying that the surface zirconium species are single-sited. The catalytic activity of these complexes was evaluated by cyanosilylation of benzaldehyde. The results showed that the catalytic activity is dependent strongly on the structure of surface species and the configuration of the ligands.

A Cohort Study of Preoperative Single Dose Versus Four Doses of Antibiotics for Patients With Non-Complicated Acute Appendicitis

Directory of Open Access Journals (Sweden)

Salah H. Al Janaby

2017-02-01

Full Text Available Objective: To Test the efficacy of single preoperative dose of Cefotaxime 1gm and Metronidazole 500mg in reducing the surgical site infections (SSIs after open appendectomy in patients with non-complicated appendicitis (NCA Place and Duration of Study: Al Hilla General Teaching Hospital, Babel Governorate-Iraq, from January 2013 to January 2014. Patients & Methods: 100 patients, who underwent appendectomy for NCA and fulfilled the selection criteria, were randomized into two groups. The patients in group A received a single dose of pre-operative antibiotics (Cefotaxime sodium and metronidazole, while the group B patients received three more dose of the same antibiotics postoperatively. Patients of both groups were followed-up for 30 days to assess the postoperative infective complications. Results: Group A had 48, while group B comprised of 52 patients. The groups were comparable in the baseline characteristics. Statistically, P value in rates of SSIs between both the groups was 0.9182. None of the patients developed intra-abdominal collection. Conclusion: Single dose of pre-operative antibiotics (Cefotaxime and metronidazole was sufficient in reducing the SSIs after appendectomy for NPA. Postoperative antibiotics did not add an appreciable clinical benefit in these patients. Key words: Preoperative antibiotics, Appendectomy, Surgical site infection, Non-complicated appendicitis Abbreviations: SSI: Surgical Site Infection, NCA: non-complicated appendicitis CDC Center of Disease Control.

Site study plan for cultural resources, Deaf Smith County site, Texas: Environmental Field Program: Preliminary draft

International Nuclear Information System (INIS)

1987-06-01

The Cultural Resources Site Study Plan describes a field program to identify and evaluate the archaeological, historical, and Native American Indian resources of the site on local and regional perspectives; monitor and manage discovered cultural resources; and establish a worker education program. The archaeological field program consists of three pedestrian surveys: Survey 1 includes two EDBH seismic survey lines and the area within the exploratory shaft facility (ESF); Survey 2 includes the remainder of the site plus a 1/4 to 3/4-mi border area; and Survey 3 includes an assortment of offsite areas. The historical studies will identify and evaluate known and discovered historical sites and structures and the Native American Indian will identify and evaluate cultural and religious concerns expressed by Indian tribal groups. Prehistoric and historic sites will be evaluated to determine if they meet eligibility criteria for listing on the National Register of Historic Places. This site study plan describes the need for each study; its design and design rationale; analysis, management, and use of data; schedule of field activities; organization of field personnel and sample management; and quality assurance requirements. The cultural resource studies will provide data for satisfying the Programmatic Agreement, engineering design needs, and SRP requirements for permits and approvals, and for minimizing effects to any cultural properties discovered during site characterization. 75 refs., 10 figs., 2 tabs

On-site detection of Phytophthora spp.—single-stranded target DNA as the limiting factor to improve on-chip hybridization

International Nuclear Information System (INIS)

Schwenkbier, Lydia; Pollok, Sibyll; Popp, Jürgen; Weber, Karina; König, Stephan; Wagner, Stefan; Werres, Sabine; Weber, Jörg; Hentschel, Martin

2014-01-01

We report on a lab-on-a-chip approach for on-site detection of Phytophthora species that allows visual signal readout. The results demonstrate the significance of single-stranded DNA (ssDNA) generation in terms of improving the intensity of the hybridization signal and to improve the reliability of the method. Conventional PCR with subsequent heat denaturation, sodium hydroxide-based denaturation, lambda exonuclease digestion and two asymmetric PCR methods were investigated for the species P. fragariae, P. kernoviae, and P. ramorum. The positioning of the capture probe within the amplified yeast GTP-binding protein (YPT1) target DNA was also of interest because it significantly influences the intensity of the signal. Statistical tests were used to validate the impact of the ssDNA generation methods and the capture-target probe position. The single-stranded target DNA generated by Linear-After-The-Exponential PCR (LATE-PCR) was found to produce signal intensities comparable to post-PCR exonuclease treatment. The LATE-PCR is the best method for the on-site detection of Phytophthora because the enzymatic digestion after PCR is more laborious and time-consuming. (author)

Single-copy insertion of transgenes in Caenorhabditis elegans

DEFF Research Database (Denmark)

Frøkjaer-Jensen, Christian; Davis, M Wayne; Hopkins, Christopher E

2008-01-01

developed a method that inserts a single copy of a transgene into a defined site. Mobilization of a Mos1 transposon generates a double-strand break in noncoding DNA. The break is repaired by copying DNA from an extrachromosomal template into the chromosomal site. Homozygous single-copy insertions can...... be obtained in less than 2 weeks by injecting approximately 20 worms. We have successfully inserted transgenes as long as 9 kb and verified that single copies are inserted at the targeted site. Single-copy transgenes are expressed at endogenous levels and can be expressed in the female and male germlines....

Site study plan for routine laboratory rock mechanics, Deaf Smith County Site, Texas: Revision 1

International Nuclear Information System (INIS)

1987-12-01

This Site Study Plan for Routine Laboratory Rock Mechanics describes routine laboratory testing to be conducted on rock samples collected as part of the characterization of the Deaf Smith County site, Texas. This study plan describes the early laboratory testing. Additional testing may be required and the type and scope of testing will be dependent upon the results of the early testing. This study provides for measurements of index, hydrological, mechanical, and chemical properties with tests which are standardized and used widely in geotechnical investigations. Another Site Study Plan for Nonroutine Laboratory Rock Mechanics describes laboratory testing of samples from the site to determine mechanical, thermomechanical, and thermal properties by less widely used methods, many of which have been developed specifically for characterization of the site. Data from laboratory tests will be used for characterization of rock strata, design of shafts and underground facilities, and modeling of repository behavior in support of resolution of both preclosure and postclosure issues. A tentative testing schedule and milestone log are given. A quality assurance program will be utilized to assure that activities affecting quality are performed correctly and that appropriate documentation is maintained. 18 refs., 8 figs., 3 tabs

Siting studies for new nuclear power plants in Argentina

International Nuclear Information System (INIS)

Barbaran, Gustavo A.

2008-01-01

This paper is a summary of the thesis prepared by the Group of Prospective and Energy Planning of the National Atomic Energy Commission for the 'Specialization on Applications of Nuclear Technology Course' of the Instituto Balseiro in 2007. It describes the evolution of siting studies through time and the main focus worldwide in this type of studies. Then, it makes a brief review of previous siting studies of nuclear power plants conducted in Argentina. It carries out a description of the methodology to conduct a site evaluation for nuclear power plants according to actual international criteria. Finally, it describes the licensing process that follows every site study. (author) [es

Analysis of laparoscopic port site complications: A descriptive study.

Science.gov (United States)

Karthik, Somu; Augustine, Alfred Joseph; Shibumon, Mundunadackal Madhavan; Pai, Manohar Varadaraya

2013-04-01

The rate of port site complications following conventional laparoscopic surgery is about 21 per 100,000 cases. It has shown a proportional rise with increase in the size of the port site incision and trocar. Although rare, complications that occur at the port site include infection, bleeding, and port site hernia. To determine the morbidity associated with ports at the site of their insertion in laparoscopic surgery and to identify risk factors for complications. Prospective descriptive study. In the present descriptive study, a total of 570 patients who underwent laparoscopic surgeries for various ailments between August 2009 and July 2011 at our institute were observed for port site complications prospectively and the complications were reviewed. Descriptive statistical analysis was carried out in the present study. The statistical software, namely, SPSS 15.0 was used for the analysis of the data. Of the 570 patients undergoing laparoscopic surgery, 17 (3%) had developed complications specifically related to the port site during a minimum follow-up of three months; port site infection (PSI) was the most frequent (n = 10, 1.8%), followed by port site bleeding (n = 4, 0.7%), omentum-related complications (n = 2; 0.35%), and port site metastasis (n = 1, 0.175%). Laparoscopic surgeries are associated with minimal port site complications. Complications are related to the increased number of ports. Umbilical port involvement is the commonest. Most complications are manageable with minimal morbidity, and can be further minimized with meticulous surgical technique during entry and exit.

Increasing STEM Exposure in K–5 Schools Through MakerSpace Use: A Multi-Site Early Success Case Study

OpenAIRE

Ortega, Veronica Inez

2017-01-01

Using Brinkerhoff’s success case methodology, this multi-site case study examined early models of MakerSpace implementation in K–5 schools in a single district. Specifically, this study examined the early use of MakerSpaces as well as the supports and barriers affecting teacher use of these spaces. The study also examined curricular connections and MakerSpace use as a conduit for purveying instruction in the soon-to-be-implemented Next Generation Science Standards. The findings of this stud...

Analysis of laparoscopic port site complications: A descriptive study

Directory of Open Access Journals (Sweden)

Somu Karthik

2013-01-01

Full Text Available Context: The rate of port site complications following conventional laparoscopic surgery is about 21 per 100,000 cases. It has shown a proportional rise with increase in the size of the port site incision and trocar. Although rare, complications that occur at the port site include infection, bleeding, and port site hernia. Aims: To determine the morbidity associated with ports at the site of their insertion in laparoscopic surgery and to identify risk factors for complications. Settings and Design: Prospective descriptive study. Materials and Methods: In the present descriptive study, a total of 570 patients who underwent laparoscopic surgeries for various ailments between August 2009 and July 2011 at our institute were observed for port site complications prospectively and the complications were reviewed. Statistical Analysis Used: Descriptive statistical analysis was carried out in the present study. The statistical software, namely, SPSS 15.0 was used for the analysis of the data. Results: Of the 570 patients undergoing laparoscopic surgery, 17 (3% had developed complications specifically related to the port site during a minimum follow-up of three months; port site infection (PSI was the most frequent (n = 10, 1.8%, followed by port site bleeding (n = 4, 0.7%, omentum-related complications (n = 2; 0.35%, and port site metastasis (n = 1, 0.175%. Conclusions: Laparoscopic surgeries are associated with minimal port site complications. Complications are related to the increased number of ports. Umbilical port involvement is the commonest. Most complications are manageable with minimal morbidity, and can be further minimized with meticulous surgical technique during entry and exit.

Analysis of laparoscopic port site complications: A descriptive study

Science.gov (United States)

Karthik, Somu; Augustine, Alfred Joseph; Shibumon, Mundunadackal Madhavan; Pai, Manohar Varadaraya

2013-01-01

CONTEXT: The rate of port site complications following conventional laparoscopic surgery is about 21 per 100,000 cases. It has shown a proportional rise with increase in the size of the port site incision and trocar. Although rare, complications that occur at the port site include infection, bleeding, and port site hernia. AIMS: To determine the morbidity associated with ports at the site of their insertion in laparoscopic surgery and to identify risk factors for complications. SETTINGS AND DESIGN: Prospective descriptive study. MATERIALS AND METHODS: In the present descriptive study, a total of 570 patients who underwent laparoscopic surgeries for various ailments between August 2009 and July 2011 at our institute were observed for port site complications prospectively and the complications were reviewed. STATISTICAL ANALYSIS USED: Descriptive statistical analysis was carried out in the present study. The statistical software, namely, SPSS 15.0 was used for the analysis of the data. RESULTS: Of the 570 patients undergoing laparoscopic surgery, 17 (3%) had developed complications specifically related to the port site during a minimum follow-up of three months; port site infection (PSI) was the most frequent (n = 10, 1.8%), followed by port site bleeding (n = 4, 0.7%), omentum-related complications (n = 2; 0.35%), and port site metastasis (n = 1, 0.175%). CONCLUSIONS: Laparoscopic surgeries are associated with minimal port site complications. Complications are related to the increased number of ports. Umbilical port involvement is the commonest. Most complications are manageable with minimal morbidity, and can be further minimized with meticulous surgical technique during entry and exit. PMID:23741110

Parameter Screening in Microfluidics Based Hydrodynamic Single-Cell Trapping

Directory of Open Access Journals (Sweden)

B. Deng

2014-01-01

Full Text Available Microfluidic cell-based arraying technology is widely used in the field of single-cell analysis. However, among developed devices, there is a compromise between cellular loading efficiencies and trapped cell densities, which deserves further analysis and optimization. To address this issue, the cell trapping efficiency of a microfluidic device with two parallel micro channels interconnected with cellular trapping sites was studied in this paper. By regulating channel inlet and outlet status, the microfluidic trapping structure can mimic key functioning units of previously reported devices. Numerical simulations were used to model this cellular trapping structure, quantifying the effects of channel on/off status and trapping structure geometries on the cellular trapping efficiency. Furthermore, the microfluidic device was fabricated based on conventional microfabrication and the cellular trapping efficiency was quantified in experiments. Experimental results showed that, besides geometry parameters, cellular travelling velocities and sizes also affected the single-cell trapping efficiency. By fine tuning parameters, more than 95% of trapping sites were taken by individual cells. This study may lay foundation in further studies of single-cell positioning in microfluidics and push forward the study of single-cell analysis.

Site study plan for borehole search and characterization, Deaf Smith County Site, Texas: Revision 1

International Nuclear Information System (INIS)

1987-01-01

This site study plan describes the Borehole Search and Characterization field activities to be conducted during the early stages of Site Characterization at the Deaf Smith County site, Texas. The field program has been designed to provide data useful in addressing information/data needs resulting from Federal/State/Local regulatory requirements and repository program requirements. Air and ground surveys, an extensive literature search, and landowner interviews will be conducted to locate wells within and adjacent to the proposed nuclear waste repository site in Deaf Smith County. Initially, the study will center around the planned Exploratory Shaft Facilities location and will expand outward from that location. Findings from this study may lead to preparation of a new site study plan to search suspected borehole locations, and excavate or reenter known boreholes for additional characterization or remedial action. The Salt Repository Project (SRP) Networks specify the schedule under which the program will operate. The Technical Field Services Contractor (TFSC) is responsible for conducting the field program. Data will be handled and reported in accordance with established SRP procedures. A quality assurance program will be utilized to assure that activities affecting quality are performed correctly and that appropriate documentation is maintained. 13 refs., 6 figs., 3 tabs

Case study of siting technology for underground nuclear power plant

International Nuclear Information System (INIS)

Hibino, Satoshi; Komada, Hiroya; Honsho, Shizumitsu; Fujiwara, Yoshikazu; Motojima, Mutsumi; Nakagawa, Kameichiro; Nosaki, Takashi

1991-01-01

Underground siting method is one of new feasible siting methods for nuclear power plants. This report presents the results on case studies on underground siting. Two sites of a steeply inclined and plateau like configurations were selected. 'Tunnel type cavern; all underground siting' method was applied for the steeply inclined configuration, and 'shaft type semi-cavern; partial underground siting' method was applied for the plateau like configuration. The following designs were carried out for these two sites as case studies; (1) conceptual designs, (2) geological surveys and rock mechanics tests, (3) stability analysis during cavern excavations, (4) seismic stability analysis of caverns during earthquake, (5) reinforcement designs for caverns, (6) drainage designs. The case studies showed that these two cases were fully feasible, and comparison between two cases revealed that the 'shaft type semi-cavern; partial underground siting' method was more suitable for Japanese islands. As a first step of underground siting, therefore, the authors recommend to construct a nuclear power plant by this method. (author)

Ground Motion Uncertainty and Variability (single-station sigma): Insights from Euroseistest, Greece

Science.gov (United States)

Ktenidou, O. J.; Roumelioti, Z.; Abrahamson, N. A.; Cotton, F.; Pitilakis, K.

2014-12-01

Despite recent improvements in networks and data, the global aleatory uncertainty (sigma) in GMPEs is still large. One reason is the ergodic approach, where we combine data in space to make up for lack of data in time. By estimating the systematic site response, we can make site-specific GMPEs and use a lower, site-specific uncertainty: single-station sigma. In this study we use the EUROSEISTEST database (http://euroseisdb.civil.auth.gr), which has two distinct advantages: good existing knowledge of site conditions at all stations, and careful relocation of the recorded events. Constraining the site and source parameters as best we can, we minimise the within- and between-events components of the global, ergodic sigma. Following that, knowledge of the site response from empirical and theoretical approaches permits us to move on to single-station sigma. The variability per site is not clearly correlated to the site class. We show that in some cases knowledge of Vs30 is not sufficient, and that site-specific data are needed to capture the response, possibly due to 2D/3D effects from complex geometry. Our values of single-station sigma are low compared to the literature. This may be due to the good ray coverage we have in all directions for small, nearby records. Indeed, our single-station sigma values are similar to published single-path values, which means that they may correspond to a fully -rather than partially- non-ergodic approach. We find larger ground motion variability for short distances and small magnitudes. This may be related to the uncertainty in the depth affecting nearby records more, or to stress drop and causing trade-offs between the source and site terms for small magnitudes.

Neutron diffraction study of single crystalline ErCo10Mo2

International Nuclear Information System (INIS)

Janssen, Y.; De Boer, F.R.; Brueck, E.; Tegus, O.; Ma, L.; Buschow, K.H.J.; Reehuis, M.

1999-01-01

Complete text of publication follows. The ferrimagnetic intermetallic compound ErCo 10 Mo 2 (Tc = 600 K) crystallizes in the tetragonal ThMn 12 -type structure (space group 14/mmm). The Co and Mo atoms may share three crystallographic sites (8f, 8i and 8j). Earlier neutron powder diffraction experiments show that Mo has a strong preference for the 8i-site and that the magnetic ordering at low temperature is planar. Furthermore ErCo 10 Mo 2 has been reported to show one [2] or more [3] spin-reorientation transitions from planar to axial magnetic ordering. Recently we succeeded in growing a single-crystalline sample of ErCo 10 Mo 2 . Magnetic measurements in 1T show one spin-reorientation transition at about 135 K. Neutron diffraction experiments were performed to investigate a possible link between the magnetic properties and the site occupation by Mo. Our results show that our sample has the Mo atoms exclusively occupying half the 8i-sites. There is no evidence for a crystallographic superstructure. Furthermore, below 150 K some reflections strongly increase due to the growing Er magnetic moment. (author)

Site characterization and validation - geophysical single hole logging

International Nuclear Information System (INIS)

Andersson, Per

1989-05-01

A total of 15 boreholes have been drilled for preliminary characterization of a previously unexplored site at the 360 and 385 m level in the Stripa mine. To adequately described the rock mass in the vicinity of these boreholes, a comprehensive program utilizing a large number of geophysical borehole methods has been carried out in 10 of these boreholes. The specific geophysical character of the rock mass and the major deformed units distinguished in the vicinity of the boreholes are recognized, and in certain cases also correlated between the boreholes. A general conclusion based on the geophysical logging results, made in this report, is that the preliminary predictions made in stage 2, of the site characterization and validation project (Olsson et.al, 1988), are adequate. The results from the geophysical logging can support the four predicted fracture/ fracture zones GHa, GHb, GA and GB whereas the predicted zones GC and GI are hard to confirm from the logging results. (author)

Site Study Plan for land use, Deaf Smith County site, Texas: Environmental Field Program: Preliminary draft

International Nuclear Information System (INIS)

1987-06-01

The Land Use Site Study Plan describes a field program consisting of characterization of the site; seismic survey rights-of-way and transportation and utility corridors, the vicinity, the region, future land use, and monitoring land-use change. Aerial photography will be used to characterize the site, seismic rows and transportation and utility corridors, and the vicinity. The resulting land-use maps and overlays will then be verified in the field. Interviews with farm managers and local experts will provide additional information. A Geographic Information System (GIS) and satellite imagery will be used to characterize the region, monitor land-use change, and provide information to assist with the future land use study. The site study plan describes the study design and rationale, the filed data collection procedures and equipment, the data analysis methods and application of results, the data management strategy, the schedule of field activities, the personnel requirements and management of the study, and the study's quality assurance program. The directives and requirements that drive these studies are derived from the Salt Repository Project Requirements Document. 51 refs; 6 figs; 3 tabs

Requirements of on-site facilities

International Nuclear Information System (INIS)

Burchardt, H.

1977-01-01

1) Requirements of on-site facilities: a) brief description of supplying the site with electricity and water; communication facilities, b) necessary facilities for containment and pipeline installation, c) necessary facilities for storage, safety, accommodation of personnel, housing; workshops; 2) Site management: a) Organisation schedules for 'turn-key-jobs' and 'single commission', b) Duties of the supervisory staff. (orig.) [de

Site characterization and validation

International Nuclear Information System (INIS)

Olsson, O.; Eriksson, J.; Falk, L.; Sandberg, E.

1988-04-01

The borehole radar investigation program of the SCV-site (Site Characterization and Validation) has comprised single hole reflection measurements with centre frequencies of 22, 45, and 60 MHz. The radar range obtained in the single hole reflection measurements was approximately 100 m for the lower frequency (22 MHz) and about 60 m for the centre frequency 45 MHz. In the crosshole measurements transmitter-receiver separations from 60 to 200 m have been used. The radar investigations have given a three dimensional description of the structure at the SCV-site. A generalized model of the site has been produced which includes three major zones, four minor zones and a circular feature. These features are considered to be the most significant at the site. Smaller features than the ones included in the generalized model certainly exist but no additional features comparable to the three major zones are thought to exist. The results indicate that the zones are not homogeneous but rather that they are highly irregular containing parts of considerably increased fracturing and parts where their contrast to the background rock is quite small. The zones appear to be approximately planar at least at the scale of the site. At a smaller scale the zones can appear quite irregular. (authors)

Laparoendoscopic single-site myomectomy and the use of fibrin sealant (Tisseel

Directory of Open Access Journals (Sweden)

Angelito Magno

2015-11-01

Full Text Available Myomectomy remains the standard surgical treatment for women with uterine myoma, who wish to preserve their fertility. However, it is often associated with increased blood loss and adhesion formation. Laparoscopic myomectomy has multiple advantages over open myomectomy1. A newer approach, laparoendoscopic single-site surgery, also known as LESS, has been developed and applied in gynecologic field.2 This is a case of a 41-year-old G2P1 patient, with the complaints of irregular menstrual cycles and lower abdominal pain for 6 months. Transvaginal ultrasound showed uterine myoma at the anterior corpus, measuring 6 × 5 cm2. The procedure is started by grasping the bilateral edges of the umbilicus with Allis forceps. A vertical incision, 1.5–2 cm, is made from the superficial skin of the umbilicus to the ventral peritoneum. A wound retractor of appropriate size is inserted and adjusted. A multiple instrument access port (LagisEndosurgical, Taichung, Taiwan is placed over the wound retractor (Figure 1. Prior to the procedure, inspection of the pelvic organs is performed to determine the pathology. Vasopressin is injected over the area of the myoma to decrease blood loss. Location of the myoma is then identified. Uterine incision is made on the serosa over the area of the myoma using the monopolar scissors. Using a bipolar instrument LigaSure®, ValleyLab, Inc., Boulder, Colorado, the incision is extended until the myoma is exposed. The myoma is grasped gently using the tenaculum forcep, and dissected bluntly along with it's pseudocapsule using the tip of suction irrigation gear. At the base of the myoma where feeding vessels may be located, coagulation by the advanced bipolar, is performed to prevent bleeding. The specimen is removed through the umbilicus. A sliding knot is made at the tail of one zero monofilament suture to fasten the anchor of the first knot. The uterus is then repaired with a continuous non-locking method. Hemostasis is

Hydrogeological study of single water conducting fracture using a crosshole hydraulic test apparatus

International Nuclear Information System (INIS)

Yamamoto, Hajime; Shimo, Michito; Yamamoto, Takuya

1998-03-01

The Crosshole Injection Test Apparatus has been constructed to evaluate the hydraulic properties and conditions, such as hydraulic conductivity and its anisotropy, storage coefficient, pore pressure etc. within a rock near a drift. The construction started in FY93 and completed on August FY96 as a set of equipments for the use of crosshole hydraulic test, which is composed of one injection borehole instrument, one observation borehole instrument and a set of on-ground instrument. In FY96, in-situ feasibility test was conducted at a 550 m level drift in Kamaishi In Situ Test Site which has been operated by PNC, and the performance of the equipment and its applicability to various types of injection method were confirmed. In this year, a hydrogeological investigation on the single water conducting fracture was conducted at a 250 m level drift in Kamaishi In Situ Test Site, using two boreholes, KCH-3 and KCH-4, both of which are 30 m depth and inclined by 45 degrees from the surface. Pressure responses at the KCH-3 borehole during the drilling of KCH-4 borehole, the results of Borehole TV logging and core observation indicated that a major conductive single-fracture was successfully isolated by the packers. As a result of a series of the single-hole and the crosshole tests (sinusoidal and constant flowrate test), the hydraulic parameters of the single-fracture (such as hydraulic conductivity and storage coefficient) were determined. This report shows all the test result, analysed data, and also describes the hydro-geological structure near the drift. (author)

Studies for site preparation for ITER construction

International Nuclear Information System (INIS)

Fardeau, A.; Blanc, F.; Cardettini, J.D.; Mandine, J.R.; Guerin, R.; Patisson, L.; Bergegere, P.; Santagiustina, A.; Garin, P.

2004-01-01

The implantation of a nuclear facility such as ITER (about 20 buildings on 40 ha) requires many preparatory studies, particularly with respect to: Underground characteristics; Topography, layout; Deforestation, excavations; Networks, fences and roads; Impact of seismic hazard on design. This paper presents the main results of these studies, carried out within the European ITER Site Studies framework. A dedicated paper in the conference deals with the transport studies. To choose the site for ITER implantation, detailed geological, hydrogeological and geophysical investigations have been carried out. Taking into account the meteorological data (particularly the main wind direction), topography, access, electrical supply, fluids needs and constraints (gravity systems), buildings and roads have been implemented. (authors)

Catalyst Architecture for Stable Single Atom Dispersion Enables Site-Specific Spectroscopic and Reactivity Measurements of CO Adsorbed to Pt Atoms, Oxidized Pt Clusters, and Metallic Pt Clusters on TiO2.

Science.gov (United States)

DeRita, Leo; Dai, Sheng; Lopez-Zepeda, Kimberly; Pham, Nicholas; Graham, George W; Pan, Xiaoqing; Christopher, Phillip

2017-10-11

Oxide-supported precious metal nanoparticles are widely used industrial catalysts. Due to expense and rarity, developing synthetic protocols that reduce precious metal nanoparticle size and stabilize dispersed species is essential. Supported atomically dispersed, single precious metal atoms represent the most efficient metal utilization geometry, although debate regarding the catalytic activity of supported single precious atom species has arisen from difficulty in synthesizing homogeneous and stable single atom dispersions, and a lack of site-specific characterization approaches. We propose a catalyst architecture and characterization approach to overcome these limitations, by depositing ∼1 precious metal atom per support particle and characterizing structures by correlating scanning transmission electron microscopy imaging and CO probe molecule infrared spectroscopy. This is demonstrated for Pt supported on anatase TiO 2 . In these structures, isolated Pt atoms, Pt iso , remain stable through various conditions, and spectroscopic evidence suggests Pt iso species exist in homogeneous local environments. Comparing Pt iso to ∼1 nm preoxidized (Pt ox ) and prereduced (Pt metal ) Pt clusters on TiO 2 , we identify unique spectroscopic signatures of CO bound to each site and find CO adsorption energy is ordered: Pt iso ≪ Pt metal atoms bonded to TiO 2 and that Pt iso exhibits optimal reactivity because every atom is exposed for catalysis and forms an interfacial site with TiO 2 . This approach should be generally useful for studying the behavior of supported precious metal atoms.

Site study plan for regional hydrologic sampling and monitoring: Preliminary draft

International Nuclear Information System (INIS)

Dutton, A.R.

1987-01-01

The purpose of the Regional Hydrologic Studies Plan is to describe those field activities required for completion of the objectives of hydrologic activities. Many of these activities are regional in scope and are designed to provide a framework for understanding the hydrologic setting of the site and the hydrologic processes that influence site characteristics. Site Study Plans (SSPs) define activates at and in the immediate vicinity of the site. The activities specified in the Regional Hydrologic Studies Plan are performed beyond the confines of the site because the hydrologic systems extend beyond the site boundaries, because pertinent data that bear on site suitability are available outside of the site, and because natural analogues exist outside of the site that allow analysis of processes that are expected to operate within the site. 15 refs., 5 figs., 1 tab

Quantifying siting difficulty: a case study of US transmission line siting

Energy Technology Data Exchange (ETDEWEB)

Vajjhala, S.P. [Resources for the Future, Washington DC (United States); Fischbeck, P.S. [Carnegie Mellon University, Pittsburgh, PA (United States). Departments of Social and Decision Sciences and Engineering and Public Policy

2007-01-15

The worldwide demand for new energy infrastructures has been paralleled in recent years by the increasing difficulty of siting major facilities. Siting difficulty is the subject of widespread discussion, but because of the complexity of the problem, potential solutions are not obvious or well understood. This paper presents a two-step policy-level framework that first develops an empirical measure of siting difficulty and then qualitatively assesses its major causes. The approach is based on the creation and aggregation of four siting indicators that are independent of the common causes and localized effects of siting problems. The proposed framework is demonstrated for the case of US transmission line siting. Results of the analyses reveal significant variations in state siting difficulty and industry experts' perceptions of its dominant causes, with implications for the long-term success of Regional Transmission Organizations (RTOs) and knowledge transfer among siting professionals in the deregulated industry. (author)

Photoelectron spectroscopy and density functional theory studies of (FeS)mH- (m = 2-4) cluster anions: effects of the single hydrogen.

Science.gov (United States)

Yin, Shi; Bernstein, Elliot R

2017-12-20

Single hydrogen containing iron hydrosulfide cluster anions (FeS) m H - (m = 2-4) are studied by photoelectron spectroscopy (PES) at 3.492 eV (355 nm) and 4.661 eV (266 nm) photon energies, and by Density Functional Theory (DFT) calculations. The structural properties, relative energies of different spin states and isomers, and the first calculated vertical detachment energies (VDEs) of different spin states for these (FeS) m H - (m = 2-4) cluster anions are investigated at various reasonable theory levels. Two types of structural isomers are found for these (FeS) m H - (m = 2-4) clusters: (1) the single hydrogen atom bonds to a sulfur site (SH-type); and (2) the single hydrogen atom bonds to an iron site (FeH-type). Experimental and theoretical results suggest such available different SH- and FeH-type structural isomers should be considered when evaluating the properties and behavior of these single hydrogen containing iron sulfide clusters in real chemical and biological systems. Compared to their related, respective pure iron sulfur (FeS) m - clusters, the first VDE trend of the diverse type (FeS) m H 0,1 - (m = 1-4) clusters can be understood through (1) the different electron distribution properties of their highest singly occupied molecular orbital employing natural bond orbital analysis (NBO/HSOMO), and (2) the partial charge distribution on the NBO/HSOMO localized sites of each cluster anion. Generally, the properties of the NBO/HSOMOs play the principal role with regard to the physical and chemical properties of all the anions. The change of cluster VDE from low to high is associated with the change in nature of their NBO/HSOMO from a dipole bound and valence electron mixed character, to a valence p orbital on S, to a valence d orbital on Fe, and to a valence p orbital on Fe or an Fe-Fe delocalized valence bonding orbital. For clusters having the same properties for NBO/HSOMOs, the partial charge distributions at the NBO/HSOMO localized sites additionally

RPAS AND TLS TECNIQUES FOR ARCHAEOLOGICAL SURVEY: THE CASE STUDY OF THE ARCHAEOLOGICAL SITE OF ERACLEA MINOA (ITALY

Directory of Open Access Journals (Sweden)

M. Lo Brutto

2017-02-01

Full Text Available Digital documentation and 3D modelling of archaeological sites are important for understanding, definition and recognition of the values of the sites and of the archaeological finds. The most part of archaeological sites are outdoor location, but a cover to preserve the ruins protects often parts of the sites. The possibility to acquire data with different techniques and merge them by using a single reference system allows creating multi-parties models in which 3D representations of the individual objects can be inserted. The paper presents the results of a recent study carried out by Geomatics Laboratory of University of Palermo for the digital documentation and 3D modelling of Eraclea Minoa archaeological site. This site is located near Agrigento, in the south of Sicily (Italy and is one of the most famous ancient Greek colonies of Sicily. The paper presents the results of the integration of different data source to survey the Eraclea Minoa archaeological site. The application of two highly versatile recording systems, the TLS (Terrestrial Laser Scanning and the RPAS (Remotely Piloted Aircraft System, allowed the Eraclea Minoa site to be documented in high resolution and with high accuracy. The integration of the two techniques has demonstrated the possibility to obtain high quality and accurate 3D models in archaeological survey.

Approaches to single-nanoparticle catalysis.

Science.gov (United States)

Sambur, Justin B; Chen, Peng

2014-01-01

Nanoparticles are among the most important industrial catalysts, with applications ranging from chemical manufacturing to energy conversion and storage. Heterogeneity is a general feature among these nanoparticles, with their individual differences in size, shape, and surface sites leading to variable, particle-specific catalytic activity. Assessing the activity of individual nanoparticles, preferably with subparticle resolution, is thus desired and vital to the development of efficient catalysts. It is challenging to measure the activity of single-nanoparticle catalysts, however. Several experimental approaches have been developed to monitor catalysis on single nanoparticles, including electrochemical methods, single-molecule fluorescence microscopy, surface plasmon resonance spectroscopy, X-ray microscopy, and surface-enhanced Raman spectroscopy. This review focuses on these experimental approaches, the associated methods and strategies, and selected applications in studying single-nanoparticle catalysis with chemical selectivity, sensitivity, or subparticle spatial resolution.

Single-well experimental design for studying residual trapping of superciritcal carbon dioxide

Energy Technology Data Exchange (ETDEWEB)

Zhang, Y.; Freifeld, B.; Finsterle, S.; Leahy, M.; Ennis-King, J.; Paterson, L.; Dance, T.

2010-06-15

The objective of our research is to design a single-well injection-withdrawal test to evaluate residual phase trapping at potential CO{sub 2} geological storage sites. Given the significant depths targeted for CO{sub 2} storage and the resulting high costs associated with drilling to those depths, it is attractive to develop a single-well test that can provide data to assess reservoir properties and reduce uncertainties in the appraisal phase of site investigation. The main challenges in a single-well test design include (1) difficulty in quantifying the amount of CO{sub 2} that has dissolved into brine or migrated away from the borehole; (2) non-uniqueness and uncertainty in the estimate of the residual gas saturation (S{sub gr}) due to correlations among various parameters; and (3) the potential biased S{sub gr} estimate due to unaccounted heterogeneity of the geological medium. To address each of these challenges, we propose (1) to use a physical-based model to simulation test sequence and inverse modeling to analyze data information content and to quantify uncertainty; (2) to jointly use multiple data types generated from different kinds of tests to constrain the Sgr estimate; and (3) to reduce the sensitivity of the designed tests to geological heterogeneity by conducting the same test sequence in both a water-saturated system and a system with residual gas saturation. To perform the design calculation, we build a synthetic model and conduct a formal analysis for sensitivity and uncertain quantification. Both parametric uncertainty and geological uncertainty are considered in the analysis. Results show (1) uncertainty in the estimation of Sgr can be reduced by jointly using multiple data types and repeated tests; and (2) geological uncertainty is essential and needs to be accounted for in the estimation of S{sub gr} and its uncertainty. The proposed methodology is applied to the design of a CO{sub 2} injection test at CO2CRC's Otway Project Site, Victoria

Transport properties of PrxOs4Sb12 single crystals with high Pr-site filling fraction grown under high pressure

International Nuclear Information System (INIS)

Tanaka, Kenya; Namiki, Takahiro; Saito, Takashi; Tatsuoka, Sho; Imamura, Atsushi; Kuwahara, Keitaro; Aoki, Yuji; Sato, Hideyuki

2009-01-01

We have succeeded in growing Pr x Os 4 Sb 12 single crystals under ∼4GPa with high Pr-site filling fraction x. The electrical resistance measurements clearly show that the superconducting (SC) transition is sharper and the onset temperatures is lower in the single crystal samples grown under high pressure compared to that of the sample grown under ambient pressure. These results suggest that the double SC transition ascribed to sample inhomogeneity is suppressed in the sample grown under high pressure. The change of 4f-electron crystalline electric field energy splitting between the Γ 1 ground state and the Γ 4 (2) first excited state in the sample made under high pressure is proposed as one of the possible origins of the suppression of the double SC transition.

Contaminant Release from Residual Waste in Single Shell Tanks at the Hanford Site, Washington, USA - 9276

International Nuclear Information System (INIS)

Cantrell, Kirk J.; Krupka, Kenneth M.; Deutsch, William J.; Lindberg, Michael J.

2009-01-01

Determinations of elemental and solid-phase compositions, and contaminant release studies have been applied in an ongoing study of residual tank wastes (i.e., waste remaining after final retrieval operations) from five of 149 underground single-shell storage tanks (241-C-103, 241-C-106, 241-C-202, 241-C-203, and 241-S-112) at the U.S. Department of Energy's Hanford Site in Washington State. This work is being conducted to support performance assessments that will be required to evaluate long-term health and safety risks associated with tank site closure. The results of studies completed to date show significant variability in the compositions, solid phase properties, and contaminant release characteristics from these residual tank wastes. This variability is the result of differences in waste chemistry/composition of wastes produced from several different spent fuel reprocessing schemes, subsequent waste reprocessing to remove certain target constituents, tank farm operations that concentrated wastes and mixed wastes between tanks, and differences in retrieval processes used to remove the wastes from the tanks. Release models were developed based upon results of chemical characterization of the bulk residual waste, solid-phase characterization (see companion paper 9277 by Krupka et al.), leaching and extraction experiments, and geochemical modeling. In most cases empirical release models were required to describe contaminant release from these wastes. Release of contaminants from residual waste was frequently found to be controlled by the solubility of phases that could not be identified and/or for which thermodynamic data and/or dissolution rates have not been measured. For example, significant fractions of Tc-99, I-129, and Cr appear to be coprecipitated at trace concentrations in metal oxide phases that could not be identified unambiguously. In the case of U release from tank 241-C-103 residual waste, geochemical calculations indicated that leachate

Single-spin addressing in an atomic Mott insulator

DEFF Research Database (Denmark)

Weitenberg, Christof; Endres, Manuel; Sherson, Jacob

2011-01-01

directly monitored the tunnelling quantum dynamics of single atoms in the lattice prepared along a single line, and observed that our addressing scheme leaves the atoms in the motional ground state. The results should enable studies of entropy transport and the quantum dynamics of spin impurities...... and quantum spin dynamics. Here we demonstrate how such control can be implemented at the most fundamental level of a single spin at a specific site of an optical lattice. Using a tightly focused laser beam together with a microwave field, we were able to flip the spin of individual atoms in a Mott insulator...... with sub-diffraction-limited resolution, well below the lattice spacing. The Mott insulator provided us with a large two-dimensional array of perfectly arranged atoms, in which we created arbitrary spin patterns by sequentially addressing selected lattice sites after freezing out the atom distribution. We...

A Case Study in the Mars Landing Site Selection for Science Objects

Directory of Open Access Journals (Sweden)

Haingja Seo

2012-12-01

Full Text Available It is a crucial matter to select a landing site for landers or rovers in planning the Mars exploration. The landing site must have not only a scientific value as a landing site, but also geographical features to lead a safe landing for Mars probes. In this regard, this study analyzed landing site of Mars probes and rovers in previous studies and discussed the adequacy of the landing site to scientific missions. Moreover, this study also examined domestic studies on the Mars. The frameworks of these studies will guide the selection of exploration sites and a landing site when sending Mars probe to the Mars through our own efforts. Additionally, this paper will be used as the preliminary data for selection of exploration site and a landing site.

Recruitment Strategies and Costs Associated With Enrolling People With Insomnia and High Blood Pressure Into an Online Behavioral Sleep Intervention: A Single-Site Pilot Study.

Science.gov (United States)

Routledge, Faye S; Davis, Tara D; Dunbar, Sandra B

Recruitment in clinical research is a common challenge and source of study failure. The reporting of recruitment methods and costs in hypertension trials is limited especially for smaller, single-site trials, online intervention trials, and trials using newer online recruitment strategies. The aims of this study are to describe and examine the feasibility of newer online-e-mail recruitment strategies and traditional recruitment strategies used to enroll participants with insomnia and high blood pressure into an online behavioral sleep intervention study (Sleeping for Heart Health). The 16 online-e-mail-based and traditional recruitment strategies used are described. Recruitment strategy feasibility was examined by study interest and enrollee yields, conversion rates, and costs (direct, remuneration, labor, and cost per enrollee). From August 2014 to October 2015, 183 people were screened and 58 (31.7%) enrolled in the study (51.1 ± 12.9 years, 63.8% female, 72.4% African American, 136 ± 12/88 ± 7 mm Hg, 87.9% self-reported hypertension, 67.2% self-reported antihypertensive medication use). The recruitment strategies yielding the highest enrollees were the university hospital phone waiting message system (25.4%), Craigslist (22.4%), and flyers (20.3%) at a per enrollee cost of $42.84, $98.90, and $128.27, respectively. The university hospital phone waiting message system (55.6%) and flyers (54.5%) had the highest interested participant to enrolled participant conversion rate of all recruitment strategies. Approximately 70% of all enrolled participants were recruited from the university hospital phone waiting message system, Craigslist, or flyers. Given the recruitment challenges that most researchers face, we encourage the documenting, assessing, and reporting of detailed recruitment strategies and associated recruitment costs so that other researchers may benefit.

Stalled repair of lesions when present within a clustered DNA damage site

International Nuclear Information System (INIS)

Lomax, M.E.; Cunniffe, S.; O'Neill, P.

2003-01-01

Ionising radiation produces clustered DNA damages (two or more lesions within one or two helical turns of the DNA) which could challenge the repair mechanism(s) of the cell. Using purified base excision repair (BER) enzymes and synthetic oligonucleotides a number of recent studies have established the excision of a lesion within clustered damage sites is compromised. Evidence will be presented that the efficiency of repair of lesions within a clustered DNA damage site is reduced, relative to that of the isolated lesions, since the lifetime of both lesions is extended by up to four fold. Simple clustered damage sites, comprised of single-strand breaks, abasic sites and base damages, one or five bases 3' or 5' to each other, were synthesised in oligonucleotides and repair carried out in mammalian cell nuclear extracts. The rate of repair of the single-strand break/abasic site within these clustered damage sites is reduced, mainly due to inhibition of the DNA ligase. The mechanism of repair of the single-strand break/abasic site shows some asymmetry. Repair appears to be by the short-patch BER pathway when the lesions are 5' to each other. In contrast, when the lesions are 3' to each other repair appears to proceed along the long-patch BER pathway. The lesions within the cluster are processed sequentially, the single-strand break/abasic site being repaired before excision of 8-oxoG, limiting the formation of double-strand breaks to <2%. Stalled processing of clustered DNA damage extends the lifetime of the lesions to an extent that could have biological consequences, e.g. if the lesions are still present during transcription and/or at replication mutations could arise

Web vulnerability study of online pharmacy sites.

Science.gov (United States)

Kuzma, Joanne

2011-01-01

Consumers are increasingly using online pharmacies, but these sites may not provide an adequate level of security with the consumers' personal data. There is a gap in this research addressing the problems of security vulnerabilities in this industry. The objective is to identify the level of web application security vulnerabilities in online pharmacies and the common types of flaws, thus expanding on prior studies. Technical, managerial and legal recommendations on how to mitigate security issues are presented. The proposed four-step method first consists of choosing an online testing tool. The next steps involve choosing a list of 60 online pharmacy sites to test, and then running the software analysis to compile a list of flaws. Finally, an in-depth analysis is performed on the types of web application vulnerabilities. The majority of sites had serious vulnerabilities, with the majority of flaws being cross-site scripting or old versions of software that have not been updated. A method is proposed for the securing of web pharmacy sites, using a multi-phased approach of technical and managerial techniques together with a thorough understanding of national legal requirements for securing systems.

Testing single-grain quartz OSL methods using sediment samples with independent age control from the Bordes-Fitte rockshelter (Roches d'Abilly site, Central France)

DEFF Research Database (Denmark)

Thomsen, Kristina Jørkov; Murray, Andrew Sean; Buylaert, Jan-Pieter

2016-01-01

We present quartz single-grain dose distributions for four well-bleached and unmixed sediment samples with independent age control (22–48 ka), from the archaeologically important Bordes-Fitte rockshelter at Roches d'Abilly, France. This site has previously been dated using 14C AMS dating and stan...

RoboSCell: An automated single cell arraying and analysis instrument

KAUST Repository

Sakaki, Kelly

2009-09-09

Single cell research has the potential to revolutionize experimental methods in biomedical sciences and contribute to clinical practices. Recent studies suggest analysis of single cells reveals novel features of intracellular processes, cell-to-cell interactions and cell structure. The methods of single cell analysis require mechanical resolution and accuracy that is not possible using conventional techniques. Robotic instruments and novel microdevices can achieve higher throughput and repeatability; however, the development of such instrumentation is a formidable task. A void exists in the state-of-the-art for automated analysis of single cells. With the increase in interest in single cell analyses in stem cell and cancer research the ability to facilitate higher throughput and repeatable procedures is necessary. In this paper, a high-throughput, single cell microarray-based robotic instrument, called the RoboSCell, is described. The proposed instrument employs a partially transparent single cell microarray (SCM) integrated with a robotic biomanipulator for in vitro analyses of live single cells trapped at the array sites. Cells, labeled with immunomagnetic particles, are captured at the array sites by channeling magnetic fields through encapsulated permalloy channels in the SCM. The RoboSCell is capable of systematically scanning the captured cells temporarily immobilized at the array sites and using optical methods to repeatedly measure extracellular and intracellular characteristics over time. The instrument\\'s capabilities are demonstrated by arraying human T lymphocytes and measuring the uptake dynamics of calcein acetoxymethylester-all in a fully automated fashion. © 2009 Springer Science+Business Media, LLC.

Single-site Green function of the Dirac equation for full-potential electron scattering

Energy Technology Data Exchange (ETDEWEB)

Kordt, Pascal

2012-05-30

I present an elaborated analytical examination of the Green function of an electron scattered at a single-site potential, for both the Schroedinger and the Dirac equation, followed by an efficient numerical solution, in both cases for potentials of arbitrary shape without an atomic sphere approximation. A numerically stable way to calculate the corresponding regular and irregular wave functions and the Green function is via the angular Lippmann-Schwinger integral equations. These are solved based on an expansion in Chebyshev polynomials and their recursion relations, allowing to rewrite the Lippmann-Schwinger equations into a system of algebraic linear equations. Gonzales et al. developed this method for the Schroedinger equation, where it gives a much higher accuracy compared to previous perturbation methods, with only modest increase in computational effort. In order to apply it to the Dirac equation, I developed relativistic Lippmann-Schwinger equations, based on a decomposition of the potential matrix into spin spherical harmonics, exploiting certain properties of this matrix. The resulting method was embedded into a Korringa-Kohn-Rostoker code for density functional calculations. As an example, the method is applied by calculating phase shifts and the Mott scattering of a tungsten impurity. (orig.)

Single-site Green function of the Dirac equation for full-potential electron scattering

International Nuclear Information System (INIS)

Kordt, Pascal

2012-01-01

I present an elaborated analytical examination of the Green function of an electron scattered at a single-site potential, for both the Schroedinger and the Dirac equation, followed by an efficient numerical solution, in both cases for potentials of arbitrary shape without an atomic sphere approximation. A numerically stable way to calculate the corresponding regular and irregular wave functions and the Green function is via the angular Lippmann-Schwinger integral equations. These are solved based on an expansion in Chebyshev polynomials and their recursion relations, allowing to rewrite the Lippmann-Schwinger equations into a system of algebraic linear equations. Gonzales et al. developed this method for the Schroedinger equation, where it gives a much higher accuracy compared to previous perturbation methods, with only modest increase in computational effort. In order to apply it to the Dirac equation, I developed relativistic Lippmann-Schwinger equations, based on a decomposition of the potential matrix into spin spherical harmonics, exploiting certain properties of this matrix. The resulting method was embedded into a Korringa-Kohn-Rostoker code for density functional calculations. As an example, the method is applied by calculating phase shifts and the Mott scattering of a tungsten impurity. (orig.)

Nuclear Energy Center Site Survey, 1975. Executive summary

International Nuclear Information System (INIS)

1976-01-01

The Nuclear Energy Center Site Survey is a study of a potential alternative siting approach for nuclear power and fuel-cycle facilities, an approach that would cluster sizable groups of such facilities on a relatively small number of sites. The largest aggregation of reactors on a single site being planned today is four, and this quad is assumed (for comparative study purposes) to be the typical dispersed site by the year 2000. Three basic types of nuclear energy centers are considered: power-plant centers, consisting of 10 to 40 nuclear electric generating units of 1200-megawatt electric capacity each; fuel-cycle centers, consisting of fuel reprocessing plants, mixed-oxide fuel fabrication facilities, and radioactive waste management facilities; and combined centers, containing both power plants and fuel-cycle facilities. The results of the general site-location screening efforts are shown on a United States map that shows the locations of large areas identified as likely to contain suitable candidate sites for power NECs, on the basis of four coarse screening criteria: water resources, seismic activity, population density, and statutory excluded lands

Reexamining microRNA site accessibility in Drosophila: a population genomics study.

Directory of Open Access Journals (Sweden)

Kevin Chen

Full Text Available Kertesz et al. (Nature Genetics 2008 described PITA, a miRNA target prediction algorithm based on hybridization energy and site accessibility. In this note, we used a population genomics approach to reexamine their data and found that the PITA algorithm had lower specificity than methods based on evolutionary conservation at comparable levels of sensitivity.We also showed that deeply conserved miRNAs tend to have stronger hybridization energies to their targets than do other miRNAs. Although PITA had higher specificity in predicting targets than a naïve seed-match method, this signal was primarily due to the use of a single cutoff score for all miRNAs and to the observed correlation between conservation and hybridization energy. Overall, our results clarify the accuracy of different miRNA target prediction algorithms in Drosophila and the role of site accessibility in miRNA target prediction.

( sup 125 I)Ifenprodil: a convenient radioligand for binding and autoradiographic studies of the polyamine-sensitive site of the NMDA receptor

Energy Technology Data Exchange (ETDEWEB)

Beart, P M; Mercer, L D; Jarrott, B [University of Melbourne, Clinical Pharmacology and Therapeutics Unit, Austin Hospital, Heidelberg, Vic (Australia)

1991-04-01

Iodination of ifenprodil, a non-competitive NMDA antagonist, with Na{sup 125}I/Chloramin-T gave a radioligand which bound rapidly and saturably to a single population of sites (dissociation constant 145 nM) in membranes of rat cerebral cortex. In competition studies, specific binding of ({sup 125}I)-ifenprodil was inhibited by analogues of ifenprodil, as well as by spermine and spermidine. Binding was sensitive to Ca{sup 2+}, Mg{sup 2+} and Zn{sup 2+}. ({sup 125}I)-Ifenprodil labelled a population of binding sites, which was topographically distributed in rat forebrain, as shown by autoradiography. ({sup 125}I)-Ifenprodil is a useful radioligand for the investigation of the polyamine site of the N-methyl-D-aspartate (NMDA) receptor-complex. (author).

Study on electroactive and electrocatalytic surfaces of single walled carbon nanotube-modified electrodes

Energy Technology Data Exchange (ETDEWEB)

Salinas-Torres, David [Departamento de Quimica Fisica and Instituto Universitario de Materiales de Alicante, Universidad de Alicante, Apdo. de Correos 99, E-03080 Alicante (Spain); Huerta, Francisco [Departamento de Ingenieria Textil y Papelera, Universidad Politecnica de Valencia, Plaza Ferrandiz y Carbonell, 1. E-03801 Alcoy (Spain); Montilla, Francisco, E-mail: francisco.montilla@ua.e [Departamento de Quimica Fisica and Instituto Universitario de Materiales de Alicante, Universidad de Alicante, Apdo. de Correos 99, E-03080 Alicante (Spain); Morallon, Emilia [Departamento de Quimica Fisica and Instituto Universitario de Materiales de Alicante, Universidad de Alicante, Apdo. de Correos 99, E-03080 Alicante (Spain)

2011-02-01

An investigation of the electrocatalysis of single-walled carbon nanotubes modified electrodes has been performed in this work. Nanotube-modified electrodes present a surface area much higher than the bare glassy carbon surfaces as determined by capacitance measurements. Several redox probes were selected for checking the reactivity of specific sites at the carbon nanotube surface. The presence of carbon nanotubes on the electrode improves the kinetics for all the reactions studied compared with the bare glassy carbon electrode with variations of the heterogeneous electron transfer rate constant up to 5 orders of magnitude. The most important effects are observed for the benzoquinone/hydroquinone and ferrocene/ferricinium redox couples, which show a remarkable improvement of their electron transfer kinetics on SWCNT-modified electrodes, probably due to strong {pi}-{pi} interaction between the organic molecules and the walls of the carbon nanotubes. For many of the reactions studied, less than 1% of the nanotube-modified electrode surface is transferring charge to species in solution. This result suggests that only nanotube tips are active sites for the electron transfer in such cases. On the contrary, the electroactive surface for the reactions of ferrocene and quinone is higher indicating that the electron transfer is produced also from the nanotube walls.

Study on electroactive and electrocatalytic surfaces of single walled carbon nanotube-modified electrodes

International Nuclear Information System (INIS)

Salinas-Torres, David; Huerta, Francisco; Montilla, Francisco; Morallon, Emilia

2011-01-01

An investigation of the electrocatalysis of single-walled carbon nanotubes modified electrodes has been performed in this work. Nanotube-modified electrodes present a surface area much higher than the bare glassy carbon surfaces as determined by capacitance measurements. Several redox probes were selected for checking the reactivity of specific sites at the carbon nanotube surface. The presence of carbon nanotubes on the electrode improves the kinetics for all the reactions studied compared with the bare glassy carbon electrode with variations of the heterogeneous electron transfer rate constant up to 5 orders of magnitude. The most important effects are observed for the benzoquinone/hydroquinone and ferrocene/ferricinium redox couples, which show a remarkable improvement of their electron transfer kinetics on SWCNT-modified electrodes, probably due to strong π-π interaction between the organic molecules and the walls of the carbon nanotubes. For many of the reactions studied, less than 1% of the nanotube-modified electrode surface is transferring charge to species in solution. This result suggests that only nanotube tips are active sites for the electron transfer in such cases. On the contrary, the electroactive surface for the reactions of ferrocene and quinone is higher indicating that the electron transfer is produced also from the nanotube walls.

Single Molecule Study of DNA Organization and Recombination

Science.gov (United States)

Xiao, Botao

We have studied five projects related to DNA organization and recombination using mainly single molecule force-spectroscopy and statistical tools. First, HU is one of the most abundant DNA-organizing proteins in bacterial chromosomes and participates in gene regulation. We report experiments that study the dependence of DNA condensation by HU on force, salt and HU concentration. A first important result is that at physiological salt levels, HU only bends DNA, resolving a previous paradox of why a chromosome-compacting protein should have a DNA-stiffening function. A second major result is quantitative demonstration of strong dependencies of HU-DNA dissociation on both salt concentration and force. Second, we have used a thermodynamic Maxwell relation to count proteins driven off large DNAs by tension, an effect important to understanding DNA organization. Our results compare well with estimates of numbers of proteins HU and Fis in previous studies. We have also shown that a semi-flexible polymer model describes our HU experimental data well. The force-dependent binding suggests mechano-chemical mechanisms for gene regulation. Third, the elusive role of protein H1 in chromatin has been clarified with purified H1 and Xenopus extracts. We find that H1 compacts DNA by both bending and looping. Addition of H1 enhances chromatin formation and maintains the plasticity of the chromatin. Fourth, the topology and mechanics of DNA twisting are critical to DNA organization and recombination. We have systematically measured DNA extension as a function of linking number density from 0.08 to -2 with holding forces from 0.2 to 2.4 pN. Unlike previous proposals, the DNA extension decreases with negative linking number. Finally, DNA recombination is a dynamic process starting from enzyme-DNA binding. We report that the Int-DBD domain of lambda integrase binds to DNA without compaction at low Int-DBD concentration. High concentration of Int-DBD loops DNA below a threshold force

Evaluation of accuracy in implant site preparation performed in single- or multi-step drilling procedures.

Science.gov (United States)

Marheineke, Nadine; Scherer, Uta; Rücker, Martin; von See, Constantin; Rahlf, Björn; Gellrich, Nils-Claudius; Stoetzer, Marcus

2018-06-01

Dental implant failure and insufficient osseointegration are proven results of mechanical and thermal damage during the surgery process. We herein performed a comparative study of a less invasive single-step drilling preparation protocol and a conventional multiple drilling sequence. Accuracy of drilling holes was precisely analyzed and the influence of different levels of expertise of the handlers and additional use of drill template guidance was evaluated. Six experimental groups, deployed in an osseous study model, were representing template-guided and freehanded drilling actions in a stepwise drilling procedure in comparison to a single-drill protocol. Each experimental condition was studied by the drilling actions of respectively three persons without surgical knowledge as well as three highly experienced oral surgeons. Drilling actions were performed and diameters were recorded with a precision measuring instrument. Less experienced operators were able to significantly increase the drilling accuracy using a guiding template, especially when multi-step preparations are performed. Improved accuracy without template guidance was observed when experienced operators were executing single-step versus multi-step technique. Single-step drilling protocols have shown to produce more accurate results than multi-step procedures. The outcome of any protocol can be further improved by use of guiding templates. Operator experience can be a contributing factor. Single-step preparations are less invasive and are promoting osseointegration. Even highly experienced surgeons are achieving higher levels of accuracy by combining this technique with template guidance. Hereby template guidance enables a reduction of hands-on time and side effects during surgery and lead to a more predictable clinical diameter.

In vitro transcription in the presence of DNA oligonucleotides can generate strong anomalous initiation sites.

Science.gov (United States)

Chow, C W; Clark, M P; Rinaldo, J E; Chalkley, R

1996-03-01

In the present study, we have explored an unexpected observation in transcription initiation that is mediated by single-stranded oligonucleotides. Initially, our goal was to understand the function of different upstream regulatory elements/initiation sites in the rat xanthine dehydrogenase/oxidase (XDH/XO) promoter. We performed in vitro transcription with HeLa nuclear extracts in the presence of different double-stranded oligonucleotides against upstream elements as competitors. A new and unusual transcription initiation site was detected by primer extension. This new initiation site maps to the downstream region of the corresponding competitor. Subsequent analyses have indicated that the induction of a new transcription initiation site is anomalous which is due to the presence of a small amount of single-stranded oligonucleotide in the competitor. We found that this anomalous initiation site is insensitive to the orientation of the promoter and requires only a small amount of single-stranded oligonucleotide (< 2-fold molar excess relative to template). We surmise that a complementary interaction between the single-stranded oligonucleotide and transiently denatured promoter template may be responsible for this sequence-specific transcription initiation artifact. To study the regulation of transcription initiation by in vitro transcription approaches, we propose that one should probe the effect of removing transacting factors by adding an excess of a cognate oligonucleotide which does not bear exact sequence identity to the template.

Clinical study evaluating bone mineral mass in the radius during skeletal growth. Single photon absorptiometry

Energy Technology Data Exchange (ETDEWEB)

Hagino, Hiroshi

1989-01-01

Using 125-I single photon absorptiometry, bone mineral measurements were performed on 206 healthy Japanese children (2 to 19 years of age). Bone mineral content (BMC), bone width (BW) and BMC/BW values were determined for the radius at distal 1/6 site (metaphysis) and distal 1/3 site (diaphysis). BMC/BW values at both sites correlated well with body height and weight. Bone mass in the diaphysis (distal 1/3 site) increased linearly during the 2-19 years of skeletal growth, but bone mass in the metaphysis (1/6 site) increased steeply during the pubertal period. In children receiving glucocorticoid therapy, bone mass was reduced in proportion to the duration of drug administration. In children under anticonvulsant therapy, the yearly increse in bone mass was significantly low especially in those patients with poor physical activity levels. Bone mineral decrease in the radius occurred in the children with hypopituitalism, hypothyroidism (cretinism), hyperthyroidism and Turner's syndrome.

Site Study Plan for laboratory soil mechanics, Deaf Smith County site, Texas: Revision 1

International Nuclear Information System (INIS)

1987-12-01

This Site Study Plan for laboratory soil mechanics describes the laboratory testing to be conducted on soil samples collected as part of the characterization of the Deaf Smith County site, Texas. This study provides for measurements of index, mechanical, thermal, hydrologic, chemical, and mineral properties of soils from boring throughout the site. Samples will be taken from Playa Borings/Trenching, Transportation/Utilities Foundation Borings, Repository Surface Facilities Design Foundation Borings, and Exploratory Shaft Facilities Design Foundation Borings. Data from the laboratory tests will be used for soil strata characterization, design of foundations for surface structures, design of transportation facilities and utility structures, design of impoundments, design of shaft lining, design of the shaft freeze wall, shaft permitting, performance assessment calculations, and other program requirements. A tentative testing schedule and milestone log are given. A quality assurance program will be utilized to assure that activities affecting quality are performed correctly and that appropriate documentation is maintained. 18 refs., 6 figs., 3 tabs

Interim pressure garment therapy (4-6 mmHg) and its effect on donor site healing in burn patients: study protocol for a randomised controlled trial.

Science.gov (United States)

Donovan, Michelle L; Muller, Michael J; Simpson, Claire; Rudd, Michael; Paratz, Jennifer

2016-04-26

Pressure garment therapy (PGT) is well accepted and commonly used by clinicians in the treatment of burns scars and grafts. The medium to high pressures (24-40 mmHg) in these garments can support scar minimisation, and evidence is well documented for this particular application. However, PGT specifically for burn donor sites, of which a sequela is also scarring, is not well documented. This study protocol investigates the impact of a low pressure (4-6 mmHg) interim garment on donor site healing and scarring. With a primary purpose of holding donor dressings in place, the application of the interim pressure garment (IPG) appears to have been twofold. IPGs for donor sites have involved inconsistent application with a focus on securing wound dressing rather than scar management. However, anecdotal and observational evidence suggests that IPGs also make a difference to some patient's scar outcomes for donor sites. This study protocol outlines a randomised controlled trial designed to test the effectiveness of this treatment on reducing scarring to burn donor sites. This study is a single-centre, single (assessor)-blinded, randomised control trial in patients with burns donor sites to their thighs. Patients will be randomly allocated to a control group (with no compression to donor sites) or to an experimental group (with compression to donor sites) as the comparative treatment. Groups will be compared at baseline regarding the important prognostic indicators: donor site location, depth, size, age, and time since graft (5 days). The IPG treatment will be administered post-operatively (on day 5). Follow-up assessments and garment replacement will be undertaken fortnightly for a period of 2 months. This study focuses on a unique area of burns scar management using a low-pressure tubular support garment for the reduction of donor site scars. Such therapy specifically for donor scar management is poorly represented in the literature. This study was designed to test a

Chemical and biological studies of the major DNA adduct of cis-diamminedichloroplatinum(II), cis-[Pt(NH3)2/d(GpG)/], built into a specific site in a viral genome

International Nuclear Information System (INIS)

Naser, L.J.; Pinto, A.L.; Lippard, S.J.; Essigmann, J.M.

1988-01-01

A duplex Escherichia coli bacteriophage M13 genome was constructed containing a single cis-[Pt(NH 3 ) 2 /d(GpG)/] intrastrand cross-link, the major DNA adduct of the anticancer drug cis-diamminedichloroplatinum(II). The duplex dodecamer d(AGAAGGCCTAGA) x d(TCTAGGCCTTCT) was ligated into the HincII site of M13mp18 to produce an insertion mutant containing a unique StuI restriction enzyme cleavage site. A genome with a 12-base gap in the minus strand was created by hybridizing HincII-linearized M13mp18 duplex DNA with the single-stranded circular DNA of the 12-base insertion mutant. Characterization by pH-dependent 1 H NMR spectroscopy established that platinum binds to the N7 positions of the adjacent guanosines. The platinated oligonucleotide was phosphorylated in the presence of [γ- 32 P]ATP with bacteriophage T4 polynucleotide kinase and incorporated into the 12-base gap of the heteroduplex, thus situating the adduct specifically within the StuI site in the minus strand of the genome. The site of incorporation of the dodecamer was mapped to the expected 36-base region delimited by the recognition sites of XbaI and HindIII. Gradient denaturing gel electrophoresis of a 289-base-pair fragment encompassing the site of adduction revealed that the presence of the cis-[Pt(NH 3 ) 2 /d)GpG)/] cross-link induces localized weakening of the DNA double helix. Comparative studies revealed no difference in survival between platinated and unmodified double-stranded genomes. In contrast, survival of the single-stranded platinated genome was only 10-12% that of the corresponding unmodified single-stranded genome, indicating that the solitary cis-[Pt(NH 3 ) 2 /d(GpG)/] cross-link is lethal to the single-stranded bacteriophage

Single molecule TPM analysis of the catalytic pentad mutants of Cre and Flp site-specific recombinases: contributions of the pentad residues to the pre-chemical steps of recombination

Science.gov (United States)

Fan, Hsiu-Fang; Cheng, Yong-Song; Ma, Chien-Hui; Jayaram, Makkuni

2015-01-01

Cre and Flp site-specific recombinase variants harboring point mutations at their conserved catalytic pentad positions were characterized using single molecule tethered particle motion (TPM) analysis. The findings reveal contributions of these amino acids to the pre-chemical steps of recombination. They suggest functional differences between positionally conserved residues in how they influence recombinase-target site association and formation of ‘non-productive’, ‘pre-synaptic’ and ‘synaptic’ complexes. The most striking difference between the two systems is noted for the single conserved lysine. The pentad residues in Cre enhance commitment to recombination by kinetically favoring the formation of pre-synaptic complexes. These residues in Flp serve a similar function by promoting Flp binding to target sites, reducing non-productive binding and/or enhancing the rate of assembly of synaptic complexes. Kinetic comparisons between Cre and Flp, and between their derivatives lacking the tyrosine nucleophile, are consistent with a stronger commitment to recombination in the Flp system. The effect of target site orientation (head-to-head or head-to-tail) on the TPM behavior of synapsed DNA molecules supports the selection of anti-parallel target site alignment prior to the chemical steps. The integrity of the synapse, whose establishment/stability is fostered by strand cleavage in the case of Flp but not Cre, appears to be compromised by the pentad mutations. PMID:25765648

Using Single-Protein Tracking to Study Cell Migration.

Science.gov (United States)

Orré, Thomas; Mehidi, Amine; Massou, Sophie; Rossier, Olivier; Giannone, Grégory

2018-01-01

To get a complete understanding of cell migration, it is critical to study its orchestration at the molecular level. Since the recent developments in single-molecule imaging, it is now possible to study molecular phenomena at the single-molecule level inside living cells. In this chapter, we describe how such approaches have been and can be used to decipher molecular mechanisms involved in cell migration.

Preferential occupation of pyroxene sites by iron in diogenite meteorites

International Nuclear Information System (INIS)

Verma, H. C.; Tewari, V. C.; Paliwal, B. S.; Tripathi, R. P.

2008-01-01

Three diogenite meteorites ALHA77256-121, Tatahounie and Bilanga are studied using Moessbauer spectroscopy to look at the iron occupancy in the two inequivalent pyroxene sites. Though the three meteorites belong to three different conditions, one is an Antarctica find, one is 75 years old fall and one is a recent fall, the iron occupancy in pyroxene sites is very similar. Fe 2+ occupies only the less distorted site and hence a single sharp doublet is observed in the Moessbauer spectra of all these samples. In contrast eucrites show a distribution of iron ions in the two sites of pyroxenes.

Mortality in single fathers compared with single mothers and partnered parents: a population-based cohort study.

Science.gov (United States)

Chiu, Maria; Rahman, Farah; Vigod, Simone; Lau, Cindy; Cairney, John; Kurdyak, Paul

2018-03-01

Single parent families, including families headed by single fathers, are becoming increasingly common around the world. Previous evidence suggests that single parenthood is associated with adverse health outcomes and increased mortality; however, most studies have focused on single mothers, with little known about the health of single fathers. This study aimed to examine mortality in a large population-based sample of Canadian single fathers compared with single mothers and partnered fathers and mothers. We used a representative sample of 871 single fathers, 4590 single mothers, 16 341 partnered fathers, and 18 688 partnered mothers from the Canadian Community Health Survey (cycles 2001-12; earliest survey date: Sept 5, 2000; latest survey date: Dec 24, 2012). We anonymously linked survey participants to health administrative database records to ascertain health status at baseline and mortality from survey date up to Oct 28, 2016. We included individuals who were aged 15 years or older, living in a household with one or more biological or adopted child younger than 25 years, and living in Ontario, and we excluded those who left Ontario during the study period or had data discrepancies. Single parents were defined as those who were divorced, separated, widowed, or single, never-married, and non-cohabitating, and partnered parents were defined as those who were married or common-law partners. We investigated differences in mortality using Cox proportional hazards models with adjustment for sociodemographic, lifestyle, and clinical factors. Median follow-up was 11·10 years (IQR 7·36-13·54). Mortality in single fathers (5·8 per 1000 person-years) was three-times higher than rates in single mothers (1·74 per 1000 person-years) and partnered fathers (1·94 per 1000 person-years). Single fathers had a significantly higher adjusted risk of dying than both single mothers (hazard ratio [HR] 2·49, 95% CI 1·20-5·15; p=0·01) and partnered fathers (2·06, 1·11-3�

Single-site community consultation for emergency research in a community hospital setting.

Science.gov (United States)

Galbraith, Kyle L; Keck, Anna-Sigrid; Little, Charletta

2014-01-01

The purpose of this study was to evaluate community member feedback from community consultation and public disclosure activities performed for a clinical investigation involving a device designed to treat traumatic brain injury in prehospital contexts. The clinical investigation of that device was to be performed under the federal regulations providing an exception from prospective informed consent requirements in emergency settings. Secondarily, we sought to assess the community consultation process by measuring the levels of outreach provided by the different communication methods used in these activities, with special attention to the effectiveness of social media for community outreach. The medical device investigation consists of a single-site pilot study based at a 345-bed community hospital in east central Illinois, which also serves as the area's only level I trauma center. Investigators, in collaboration with the local institutional review board, fulfilled community consultation and public disclosure requirements through four public town hall meetings, seven targeted focus groups, targeted mailings to 884 community leaders and researchers, a press conference and press release, internal and external websites, and multiple postings to the hospital's Facebook and Twitter accounts. Community members provided feedback by completing paper or electronic comment cards. A total of 428 community members attended the four town hall meetings and seven focus group sessions. Attendance at each meeting ranged from 4 to 20 attendees for the town hall meetings and 8 to 140 attendees for the focus groups. The investigation's external website received 626 unique visitors and the intranet website received 528 unique visits. Social media postings on Facebook and Twitter received six comments and eight "likes" to indicate that an individual read the posting. In total, attendees completed 175 comment cards to provide their feedback. Community member attitudes regarding the

EPR and optical absorption studies of VO2+ doped L-alanine (C3H7NO2) single crystals

International Nuclear Information System (INIS)

Biyik, Recep

2009-01-01

VO 2+ doped L-alanine (C 3 H 7 NO 2 ) single crystals and powders are examined by electron paramagnetic resonance (EPR) and optical absorption spectroscopy. Three magnetically different sites are resolved from angular variations of L-alanine single crystal EPR spectra. In some specific orientations each VO 2+ line splits into three superhyperfine lines with intensities of 1:2:1 and maximum splitting value of 2.23 mT. The local symmetries of VO 2+ complex sites are nearly axial. The optical absorption spectra show three bands. Spin Hamiltonian parameters are measured and molecular orbital coefficients are calculated by correlating EPR and optical absorption data for the central vanadyl ion.

The single-particle mixing state and cloud scavenging of black carbon: a case study at a high-altitude mountain site in southern China

Science.gov (United States)

Zhang, Guohua; Lin, Qinhao; Peng, Long; Bi, Xinhui; Chen, Duohong; Li, Mei; Li, Lei; Brechtel, Fred J.; Chen, Jianxin; Yan, Weijun; Wang, Xinming; Peng, Ping'an; Sheng, Guoying; Zhou, Zhen

2017-12-01

In the present study, a ground-based counterflow virtual impactor (GCVI) was used to sample cloud droplet residual (cloud RES) particles, while a parallel PM2.5 inlet was used to sample cloud-free or cloud interstitial (cloud INT) particles. The mixing state of black carbon (BC)-containing particles and the mass concentrations of BC in the cloud-free, RES and INT particles were investigated using a single-particle aerosol mass spectrometer (SPAMS) and two aethalometers, respectively, at a mountain site (1690 m a. s. l. ) in southern China. The measured BC-containing particles were extensively internally mixed with sulfate and were scavenged into cloud droplets (with number fractions of 0.05-0.45) to a similar (or slightly lower) extent as all the measured particles (0.07-0.6) over the measured size range of 0.1-1.6 µm. The results indicate the preferential activation of larger particles and/or that the production of secondary compositions shifts the BC-containing particles towards larger sizes. BC-containing particles with an abundance of both sulfate and organics were scavenged less than those with sulfate but limited organics, implying the importance of the mixing state on the incorporation of BC-containing particles into cloud droplets. The mass scavenging efficiency of BC with an average of 33 % was similar for different cloud events independent of the air mass. This is the first time that both the mixing state and cloud scavenging of BC in China have been reported. Our results would improve the knowledge on the concentration, mixing state, and cloud scavenging of BC in the free troposphere.

Exploiting nanospace for asymmetric catalysis: confinement of immobilized, single-site chiral catalysts enhances enantioselectivity.

Science.gov (United States)

Thomas, John Meurig; Raja, Robert

2008-06-01

In the mid-1990s, it became possible to prepare high-area silicas having pore diameters controllably adjustable in the range ca. 20-200 Å. Moreover, the inner walls of these nanoporous solids could be functionalized to yield single-site, chiral, catalytically active organometallic centers, the precise structures of which could be determined using in situ X-ray absorption and FTIR and multinuclear magic angle spinning (MAS) NMR spectroscopy. This approach opened up the prospect of performing heterogeneous enantioselective conversions in a novel manner, under the spatial restrictions imposed by the nanocavities within which the reactions occur. In particular, it suggested an alternative method for preparing pharmaceutically and agrochemically useful asymmetric products by capitalizing on the notion, initially tentatively perceived, that spatial confinement of prochiral reactants (and transition states formed at the chiral active center) would provide an altogether new method of boosting the enantioselectivity of the anchored chiral catalyst. Initially, we anchored chiral single-site heterogeneous catalysts to nanopores covalently via a ligand attached to Pd(II) or Rh(I) centers. Later, we employed a more convenient and cheaper electrostatic method, relying in part on strong hydrogen bonding. This Account provides many examples of these processes, encompassing hydrogenations, oxidations, and aminations. Of particular note is the facile synthesis from methyl benzoylformate of methyl mandelate, which is a precursor in the synthesis of pemoline, a stimulant of the central nervous system; our procedure offers several viable methods for reducing ketocarboxylic acids. In addition to relying on earlier (synchrotron-based) in situ techniques for characterizing catalysts, we have constructed experimental procedures involving robotically controlled catalytic reactors that allow the kinetics of conversion and enantioselectivity to be monitored continually, and we have access to

Case studies of community relations on DOE's Formerly Utilized Sites Remedial Action Program as models for Superfund sites

International Nuclear Information System (INIS)

Plant, S.W.; Adler, D.G.

1995-01-01

Ever since the US Department of Energy (DOE) created its Formerly Utilized Sites Remedial Action Program (FUSRAP) in 1974, there has been a community relations program. The community relations effort has grown as FUSRAP has grown. With 20 of 46 sites now cleaned up, considerable experience in working with FUSRAP stakeholders has been gained. Why not share that experience with others who labor on the Superfund sites? Many similarities exist between the Superfund sites and FUSRAP. FUSRAP is a large, multiple-site environmental restoration program. The challenges range from small sites requiring remedial actions measurable in weeks to major sites requiring the full remedial investigation/feasibility study process. The numerous Superfund sites throughout the United States offer the same diversity, both geographically and technically. But before DOE offers FUSRAP's community relations experience as a model, it needs to make clear that this will be a realistic model. As experiences are shared, DOE will certainly speak of the efforts that achieved its goals. But many of the problems that DOE encountered along the way will also be related. FUSRAP relies on a variety of one- and two-way communication techniques for involving stakeholders in the DOE decision-making process. Some of the techniques and experiences from the case studies are presented

Toxin MqsR Cleaves Single-Stranded mRNA with Various 5 Ends

Science.gov (United States)

2016-08-24

either protein ORIGINAL RESEARCH Toxin MqsR cleaves single- stranded mRNA with various 5’ ends Nityananda Chowdhury1,*, Brian W. Kwan1,*, Louise C...in which a single 5′- GCU site was predicted to be single- stranded (ssRNA), double- stranded (dsRNA), in the loop of a stem - loop (slRNA), or in a...single- stranded 5′- GCU sites since cleavage was approximately 20- fold higher than cleavage seen with the 5′- GCU site in the stem - loop and

Adsorption and pathways of single atomistic processes on NbN (0 0 1) and (1 1 1) surfaces: A first-principle study

International Nuclear Information System (INIS)

Ren, Yuan; Liu, Xuejie; Tan, Xin; Sun, Shiyang; Wei, Huai; Lu, Feng

2014-01-01

Highlights: • We investigate the behaviors of Nb, Si, N atom on NbN(0 0 1) and (1 1 1) surfaces. • The adsorption and diffusion of single atom on NbN(0 0 1) and (1 1 1) were calculated by DFT. • The potential energy surface of single atom on NbN(0 0 1) and (1 1 1) surfaces were investigated. • The diffusion process of single on NbN(0 0 1) and (1 1 1) were calculated by nudged elastic band. - Abstract: The adsorption and pathway processes of atomistic Nb, Si, and N at high-symmetry sites on NbN (0 0 1) and (1 1 1) surfaces were studied using first-principle method, which is based on the density functional theory. This investigation presents some of the results obtained. The potential energy surface (PES) was obtained by calculating the adsorption of Nb, Si, and N atoms on NbN (0 0 1). The most energetic site for the Nb atom adsorbed on NbN(0 0 1) was the site ‘on-top of face–center cubic’ (HL), whereas those for N and Si were both at the site ‘between TopN and HL’ (TopN-HL). The minimum energy paths of the single atom on NbN (0 0 1) surface diffusion were obtained using the PES calculation results. The Nb and Si atoms were diffused from the TopN to the HL position. The N atom was diffused from the TopNb, whereas the TopN–HL to HL position. The diffusion energies of the Nb, Si, and N atoms on the NbN (0 0 1) surface were 0.32, 0.69, and 1.32 eV, respectively. The pathways of the atomistic diffusion involved the diffusion of atoms from the FCC to the HCP site on the NbN (1 1 1) surface. The results showed that the diffusion energy of Si on the Nb layer was smaller than that on the N layer. Si and N can easily form stable structures while bonding on the N layer. Moreover, Si atoms can stabilize the activity of N atoms while promoting the spread of Nb atoms during deposition

Site and feasibility studies of a first nuclear power plant in Morocco

International Nuclear Information System (INIS)

Righi, M.

1988-11-01

Basing on the estimated studies related to the evaluation of future needs of electrical energy, the launching of a nuclear power program in Morocco is confirmed necessary. A complete study of sites and feasibility has been carried out. Taking into account the site selection factors two sites: BIR ELHAR and SIDI BOULBRA have been kept as candidate sites. The evaluation of seismic and geotechnical risks of the power plant impact on the environment and risks related to human activities has led to privilege the SIDI BOULBRA site. The studies for confirming this site are summarized. 4 figs. (F.M.)

Studying Chemical Reactions, One Bond at a Time, with Single Molecule AFM Techniques

Science.gov (United States)

Fernandez, Julio M.

2008-03-01

The mechanisms by which mechanical forces regulate the kinetics of a chemical reaction are unknown. In my lecture I will demonstrate how we use single molecule force-clamp spectroscopy and protein engineering to study the effect of force on the kinetics of thiol/disulfide exchange. Reduction of disulfide bond via the thiol/disulfide exchange chemical reaction is crucial in regulating protein function and is of common occurrence in mechanically stressed proteins. While reduction is thought to proceed through a substitution nucleophilic bimolecular (SN2) reaction, the role of a mechanical force in modulating this chemical reaction is unknown. We apply a constant stretching force to single engineered disulfide bonds and measure their rate of reduction by dithiothreitol (DTT). We find that while the reduction rate is linearly dependent on the concentration of DTT, it is exponentially dependent on the applied force, increasing 10-fold over a 300 pN range. This result predicts that the disulfide bond lengthens by 0.34 å at the transition state of the thiol/disulfide exchange reaction. In addition to DTT, we also study the reduction of the engineered disulfide bond by the E. coli enzyme thioredoxin (Trx). Thioredoxins are enzymes that catalyze disulfide bond reduction in all organisms. As before, we apply a mechanical force in the range of 25-450 pN to the engineered disulfide bond substrate and monitor the reduction of these bonds by individual enzymes. In sharp contrast with the data obtained with DTT, we now observe two alternative forms of the catalytic reaction, the first requiring a reorientation of the substrate disulfide bond, causing a shortening of the substrate polypeptide by 0.76±0.07 å, and the second elongating the substrate disulfide bond by 0.21±0.01 å. These results support the view that the Trx active site regulates the geometry of the participating sulfur atoms, with sub-ångström precision, in order to achieve efficient catalysis. Single molecule

Single gold nanoparticle plasmonic spectroscopy for study of chemical-dependent efflux function of single ABC transporters of single live Bacillus subtilis cells.

Science.gov (United States)

Browning, Lauren M; Lee, Kerry J; Cherukuri, Pavan K; Huang, Tao; Songkiatisak, Preeyaporn; Warren, Seth; Xu, Xiao-Hong Nancy

2018-03-26

ATP-binding cassette (ABC) membrane transporters serve as self-defense transport apparatus in many living organisms and they can selectively extrude a wide variety of substrates, leading to multidrug resistance (MDR). The detailed molecular mechanisms remain elusive. Single nanoparticle plasmonic spectroscopy highly depends upon their sizes, shapes, chemical and surface properties. In our previous studies, we have used the size-dependent plasmonic spectra of single silver nanoparticles (Ag NPs) to study the real-time efflux kinetics of the ABC (BmrA) transporter and MexAB-OprM transporter in single live cells (Gram-positive and Gram-negative bacterium), respectively. In this study, we prepared and used purified, biocompatible and stable (non-aggregated) gold nanoparticles (Au NPs) (12.4 ± 0.9 nm) to study the efflux kinetics of single BmrA membrane transporters of single live Bacillus subtillis cells, aiming to probe chemical dependent efflux functions of BmrA transporters and their potential chemical sensing capability. Similar to those observed using Ag NPs, accumulation of the intracellular Au NPs in single live cells (WT and ΔBmrA) highly depends upon the cellular expression of BmrA and the NP concentration (0.7 and 1.4 nM). The lower accumulation of intracellular Au NPs in WT (normal expression of BmrA) than ΔBmrA (deletion of bmrA) indicates that BmrA extrudes the Au NPs out of the WT cells. The accumulation of Au NPs in the cells increases with NP concentration, suggesting that the Au NPs most likely passively diffuse into the cells, similar to antibiotics. The result demonstrates that such small Au NPs can serve as imaging probes to study the efflux function of the BmrA membrane transporter in single live cells. Furthermore, the dependence of the accumulation rate of intracellular Au NPs in single live cells upon the expression of BmrA and the concentration of the NPs is about twice higher than that of the same sized Ag NPs. This interesting finding

Status of siting studies for a near surface repository site for radioactive wastes in the Philippines

International Nuclear Information System (INIS)

Valdezco, E.M.; Palattao, M.V.B.; Marcelo, E.A.; Caseria, E.S.; Venida, L.L.; Cruz, J.M. dela

2002-01-01

The Philippines, through the Philippine Nuclear Research Institute (PNRI), decided to conduct a study on siting a low level radioactive waste disposal facility. The infrastructure set up for this purpose, the radioactive waste disposal concept, the overall siting process, the methodology applied and preliminary results obtained are described in this paper. (author)

Site Study Plan for Aesthetics, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary draft

International Nuclear Information System (INIS)

1987-06-01

The Aesthetic Site Study Plan describes a field program consisting of identification of the visually affected area; determination of scenic quality, visual sensitivity, and visual management classes of the site and vicinity; and analysis of the level of visual contrast that would be created by the project. Field ratings of scenic quality, visual sensitivity, and visual contrast will be supplemented by a public perception survey designed to incorporate the views of the public. This plan describes the need for the study, the study design, data management and use, schedule for proposed activities, and quality assurance program. This study will provide data needed to satisfy requirements contained in, or derived from, SRPO Requirement Document (SRP-RD). 35 refs., 6 figs., 2 tabs

A study of moult-site fidelity in Egyptian geese, Alopochen ...

African Journals Online (AJOL)

Little is known about moult and moult-site fidelity of African waterfowl. Satellite telemetry and uniquely engraved colour-rings were used to study moult-site fidelity of Egyptian geese marked at two sites in South Africa – Barberspan in the summer-rainfall region and Strandfontein in the winter-rainfall region. Twelve Egyptian ...

Transumbilical laparoendoscopic single-site donor nephrectomy: Without the use of a single port access device

Directory of Open Access Journals (Sweden)

Deepak Dubey

2011-01-01

Conclusions : Transumbilical LESS-DN can be cost-effectively performed using conventional laparoscopy instruments and without the need for a single port access device. Warm ischemia times with this technique are comparable with that during conventional multiport laparoscopic donor nephrectomy.

Site specific study for possible ongoing salt dome movement

International Nuclear Information System (INIS)

Thoms, R.L.; Manning, T.A.; Paille, L.K.; Gehle, R.M.

1977-01-01

U.S. Gulf Coast salt domes, among other geologic structures, currently are being considered for storage of commercial radioactive wastes. A major concern with dome storage of long lived radioactive wastes lies with the possible tectonic movement of the host dome. Any ongoing movement of a salt dome can be monitored with a site specific complementary system of field instrumentation and finite element modelling. Field instrumentation and accompanying finite element analyses for a study dome in northwest Louisiana are described. Site specific data and early experience associated with tiltmeters over the dome are presented. Also, recommendations are made for modifications and extensions of the field instrumentation and finite element modelling appropriate to the specific site under study

SITE: a methodology for assessment of energy facility siting patterns. Regional studies program

International Nuclear Information System (INIS)

Frigerio, N.A.; Habegger, L.J.; King, R.F.; Hoover, L.J.; Clark, N.A.; Cobian, J.M.

1975-08-01

The timely development of the nation's energy production capacity in a manner that minimizes potential adverse local and regional impacts associated with energy facilities requires the use of sophisticated techniques for evaluation of siting alternatives and fuel cycle options. This report is a documentation of the computerized SITE methodology that has been developed for evaluating health, environmental, and socioeconomic impacts related to utilization of alternate sites for energy production within a region of interest. The cost, impact, and attribute vectors, which are generated and displayed on density maps, can be used in a multiparameter overlay process to identify preferable siting areas. The assessment of clustered facilities in energy centers is also possible within the SITE analysis framework. An application of the SITE methodology to Northern Illinois is presented. Also included is a description of the ongoing extension of SITE for the accumulative evaluation of alternative regional energy siting patterns and fuel cycle options. An appendix provides documentation and user information for the SITE computer program

Site Study Plan for meteorology/air quality, Deaf Smith County site, Texas: Environmental Field Program: Preliminary draft

International Nuclear Information System (INIS)

1987-06-01

The Meteorological/Air Quality Site Study Plan describes a field program consisting of continuous measurements of surface (10-meter) wind speed and direction, temperature, humidity, dew point, pressure, and sensible heat flux (vertical). Air quality measurements will be limited to suspended particulate matter. After the first year of measurements, a 60-meter tower will be added to incorporate measurements needed for later modeling and dose calculations; these will include upper level winds, vertical temperature structure, and vertical wind speed. All of these measurements will be made at a site located within the 9-mi 2 site area but remote from the ESF. A second site, located near and downwind from the ESF, will monitor only particulate matter. The SSP describes the need for each study; its design and design rationale; analysis, management, and use of data, schedule of field activities, organization of field personnel and sample management, and quality assurance requirements. These studies will provide data needed to satisfy requirements contained in, or derived from the Salt Repository Project Requirements Document. 38 refs., 8 figs., 3 tabs

Chronic neural probe for simultaneous recording of single-unit, multi-unit, and local field potential activity from multiple brain sites

Science.gov (United States)

Pothof, F.; Bonini, L.; Lanzilotto, M.; Livi, A.; Fogassi, L.; Orban, G. A.; Paul, O.; Ruther, P.

2016-08-01

Objective. Drug resistant focal epilepsy can be treated by resecting the epileptic focus requiring a precise focus localisation using stereoelectroencephalography (SEEG) probes. As commercial SEEG probes offer only a limited spatial resolution, probes of higher channel count and design freedom enabling the incorporation of macro and microelectrodes would help increasing spatial resolution and thus open new perspectives for investigating mechanisms underlying focal epilepsy and its treatment. This work describes a new fabrication process for SEEG probes with materials and dimensions similar to clinical probes enabling recording single neuron activity at high spatial resolution. Approach. Polyimide is used as a biocompatible flexible substrate into which platinum electrodes and leads are integrated with a minimal feature size of 5 μm. The polyimide foils are rolled into the cylindrical probe shape at a diameter of 0.8 mm. The resulting probe features match those of clinically approved devices. Tests in saline solution confirmed the probe stability and functionality. Probes were implanted into the brain of one monkey (Macaca mulatta), trained to perform different motor tasks. Suitable configurations including up to 128 electrode sites allow the recording of task-related neuronal signals. Main results. Probes with 32 and 64 electrode sites were implanted in the posterior parietal cortex. Local field potentials and multi-unit activity were recorded as early as one hour after implantation. Stable single-unit activity was achieved for up to 26 days after implantation of a 64-channel probe. All recorded signals showed modulation during task execution. Significance. With the novel probes it is possible to record stable biologically relevant data over a time span exceeding the usual time needed for epileptic focus localisation in human patients. This is the first time that single units are recorded along cylindrical polyimide probes chronically implanted 22 mm deep into the

Towards the Study of the Early Medieval Site Bashanta-II

Directory of Open Access Journals (Sweden)

Ochir-Goryaeva Maria A.

2016-12-01

Full Text Available The authors offer preliminary results on study of a new early medieval site discovered in the Gorodovikovo District (Kalmykia during a field survey near Bashanta-I hillfort at Chapaevskoe Lake (or Tsagan nur in Kalmyk language. The new site is found 8 km to the south-west from Bashanta-I hillfort, on the bank of the Egorlyk River. The site is dated by two radiocarbon dates by the middle of the 7th – late 8th centuries, i.e. by the time of Khazar Khanate. Some preliminary studies on the site included topographical mapping, collection of stray finds and a few prospection pits. These activities yielded numerous ceramic sherds, roof tiles and debris of masonry. Judging by the existing cultural stratum, remains of stone structures made of shell stone blocks and numerous ceramic finds of good quality, the new site was a settlement of Saltovo-Mayaki Culture, presumably a satellite hillfort. The identity of ceramics and construction materials allowed the authors to name this new site as Bashanta-II.

Ultrasound-Guided Intermediate Site Greater Occipital Nerve Infiltration: A Technical Feasibility Study.

Science.gov (United States)

Zipfel, Jonathan; Kastler, Adrian; Tatu, Laurent; Behr, Julien; Kechidi, Rachid; Kastler, Bruno

2016-01-01

Two studies recently reported that computed tomography (CT) guided infiltration of the greater occipital nerve at its intermediate site allows a high efficacy rate with long-lasting pain relief following procedure in occipital neuralgia and in various craniofacial pain syndromes. The purpose of our study was to evaluate the technical feasibility and safety of ultrasound-guided intermediate site greater occipital nerve infiltration. Retrospective study. This study was conducted at the imaging department of a 1,409 bed university hospital. Local institutional review board approval was obtained and written consent was waived. In this retrospective study, 12 patients suffering from refractory occipital neuralgia or craniofacial pain syndromes were included between April and October 2014. They underwent a total of 21 ultrasound-guided infiltrations. Infiltration of the greater occipital nerve was performed at the intermediate site of the greater occipital nerve, at its first bend between obliqus capitis inferior and semispinalis capitis muscles with local anestetics and cortivazol. Technical success was defined as satisfactory diffusion of added iodinated contrast media in the fatty space between these muscles depicted on control CT scan. We also reported first data of immediate block test efficacy and initial clinical efficacy at 7 days, one month, and 3 months, defined by a decrease of at least 50% of visual analog scale (VAS) scores. Technical success rate was 95.24%. Patients suffered from right unilateral occipital neuralgia in 3 cases, left unilateral occipital neuralgia in 2 cases, bilateral occipital neuralgia in 2 cases, migraine in one case, cervicogenic headache in one case, tension-type headache in 2 cases, and cluster headache in one case. Block test efficacy was found in 93.3% (14/15) cases. Clinical efficacy was found in 80% of cases at 7 days, in 66.7% of cases at one month and in 60% of cases at 3 months. No major complications were noted. Some of the

Temporally-controlled site-specific recombination in zebrafish.

Directory of Open Access Journals (Sweden)

Stefan Hans

Full Text Available Conventional use of the site-specific recombinase Cre is a powerful technology in mouse, but almost absent in other vertebrate model organisms. In zebrafish, Cre-mediated recombination efficiency was previously very low. Here we show that using transposon-mediated transgenesis, Cre is in fact highly efficient in this organism. Furthermore, temporal control of recombination can be achieved by using the ligand-inducible CreER(T2. Site-specific recombination only occurs upon administration of the drug tamoxifen (TAM or its active metabolite, 4-hydroxy-tamoxifen (4-OHT. Cre-mediated recombination is detectable already 4 or 2 hours after administration of TAM or 4-OHT, demonstrating fast recombination kinetics. In addition, low doses of TAM allow mosaic labeling of single cells. Combined, our results show that conditional Cre/lox will be a valuable tool for both, embryonic and adult zebrafish studies. Furthermore, single copy insertion transgenesis of Cre/lox constructs suggest a strategy suitable also for other organisms.

Site Study Plan for salt, Deaf Smith County site, Texas: Environmental Field Program: Preliminary draft

International Nuclear Information System (INIS)

1987-06-01

The Salt Site Study Plan (SSP) describes a program for characterizing the existing salt environment in the site vicinity. A step-by-step approach is described which proceeds from published data and planned theoretical studies, to planned laboratory studies, and finally to planned field studies, to provide the necessary data to meet program requirements contained in the Salt Repository Project - Requirements Document (SRP-RD). The plan also draws on the results of other SSP's for certain data; for example, soil salinity data are to be provided under the Soils SSP. The salt studies consist of evaluation of control and mitigation measures, salt monitoring studies, emission factors development, air models development and validation, and risk assessment. For each study, its design and design rationale; analysis, management, and use of data; schedule of activities; organization of personnel and sample management; and quality assurance requirements are described. 90 refs., 9 figs., 7 tabs

The glass block site radionuclide migration study

International Nuclear Information System (INIS)

Killey, R.W.D.; Champ, D.R.

1990-01-01

In 1960 25 nepheline syenite glass blocks containing 14 TBq of mixed fission products in 50 kg of glass were placed below the water table in a shallow sand aquifer at Chalk River Laboratories. Experimental studies undertaken at the site since 1960 have included detailed mapping of the plume of 90 Sr in 1963, 1966 and 1971. Mathematical modeling studies have employed the radiostrontium plume data in determining the split between ion exchange and chemisorption of 90 Sr, and in obtaining reaction rate data for chemisorption. The distribution of 137 Cs on downgradient soils was mapped in 1963 and 1979. An extended plume of low-level 137 Cs contamination observed in the 1979 study prompted an investigation of the role of particulate materials in radionuclide transport. IN 1983, large volume groundwater sampling and separation of cationic, anionic, and neutral dissolved species, as well as particulates, detected anionic and cationic dissolved europium isotopes (154 and 155), and again encountered particulate 137 Cs. A variety of investigations of cesium and strontium sorption have provided a data base on sediment mineralogy, particle surface features, and information on sorption sites and processes. The year 1990 saw the inauguration of a three-year program to update investigations of radionuclide release, transport, and sorption at the glass block site. The first stage of the program has been a detailed definition and simulation of the hydrogeologic setting. Plume mapping and aqueous speciation studies are in progress. This paper summarizes past investigations, reviews the status of the current program, and discusses components of future studies, including investigations of sediment sorption mechanisms. (Author) (17 refs., 8 figs.)

Small Scale Multisource Site – Hydrogeology Investigation

Science.gov (United States)

A site impacted by brackish water was evaluated using traditional hydrogeologic and geochemical site characterization techniques. No single, specific source of the brine impacted ground water was identified. However, the extent of the brine impacted ground water was found to be...

Deficient prepulse inhibition in schizophrenia detected by the multi-site COGS.

Science.gov (United States)

Swerdlow, Neal R; Light, Gregory A; Sprock, Joyce; Calkins, Monica E; Green, Michael F; Greenwood, Tiffany A; Gur, Raquel E; Gur, Ruben C; Lazzeroni, Laura C; Nuechterlein, Keith H; Radant, Allen D; Ray, Amrita; Seidman, Larry J; Siever, Larry J; Silverman, Jeremy M; Stone, William S; Sugar, Catherine A; Tsuang, Debby W; Tsuang, Ming T; Turetsky, Bruce I; Braff, David L

2014-02-01

Startle inhibition by weak prepulses (PPI) is studied to understand the biology of information processing in schizophrenia patients and healthy comparison subjects (HCS). The Consortium on the Genetics of Schizophrenia (COGS) identified associations between PPI and single nucleotide polymorphisms in schizophrenia probands and unaffected relatives, and linkage analyses extended evidence for the genetics of PPI deficits in schizophrenia in the COGS-1 family study. These findings are being extended in a 5-site "COGS-2" study of 1800 patients and 1200 unrelated HCS to facilitate genetic analyses. We describe a planned interim analysis of COGS-2 PPI data. Eyeblink startle was measured in carefully screened HCS and schizophrenia patients (n=1402). Planned analyses of PPI (60 ms intervals) assessed effects of diagnosis, sex and test site, PPI-modifying effects of medications and smoking, and relationships between PPI and neurocognitive measures. 884 subjects met strict inclusion criteria. ANOVA of PPI revealed significant effects of diagnosis (p=0.0005) and sex (pschizophrenia PPI differences were greatest among patients not taking 2nd generation antipsychotics, and were independent of smoking status. Modest but significant relationships were detected between PPI and performance in specific neurocognitive measures. The COGS-2 multi-site study detects schizophrenia-related PPI deficits reported in single-site studies, including patterns related to diagnosis, prepulse interval, sex, medication and other neurocognitive measures. Site differences were detected and explored. The target COGS-2 schizophrenia "endophenotype" of reduced PPI should prove valuable for identifying and confirming schizophrenia risk genes in future analyses. Copyright © 2013 Elsevier B.V. All rights reserved.

Siting study for small platform-mounted industrial energy reactors

International Nuclear Information System (INIS)

1975-07-01

Utilizing an existing 313 MW(t) ship propulsion reactor design, a concept has been formulated for a floating platform-mounted nuclear plant and an evaluation has been made to determine reductions in construction time and cost achievable by repetitive platform construction in a shipyard. Concepts and estimates are presented for siting platform-mounted nuclear plants at the location of industrial facilities where the nuclear plants would furnish industrial process heat and/or electrical power. The representative industrial site designated for this study is considered typical of sites that might be used along the extensive network of navigable canals adjacent to the ocean and is similar to potential sites along the inland waterways of the United States

Site-controlled quantum dots fabricated using an atomic-force microscope assisted technique

Directory of Open Access Journals (Sweden)

Sakuma Y

2006-01-01

Full Text Available AbstractAn atomic-force microscope assisted technique is developed to control the position and size of self-assembled semiconductor quantum dots (QDs. Presently, the site precision is as good as ± 1.5 nm and the size fluctuation is within ± 5% with the minimum controllable lateral diameter of 20 nm. With the ability of producing tightly packed and differently sized QDs, sophisticated QD arrays can be controllably fabricated for the application in quantum computing. The optical quality of such site-controlled QDs is found comparable to some conventionally self-assembled semiconductor QDs. The single dot photoluminescence of site-controlled InAs/InP QDs is studied in detail, presenting the prospect to utilize them in quantum communication as precisely controlled single photon emitters working at telecommunication bands.

Archaeometric studies on the Hatahara archaeological site

International Nuclear Information System (INIS)

Nunes, Kelly Placa

2009-01-01

The reconstruction of the past and the understanding of historical and cultural aspects of societies that developed at archaeological sites have been enabled by archaeometric studies undertaken on ceramics located at these areas. This study aims to be a contribution to the elucidation of these aspects with the application of three physical methods of analysis: neutron activation analysis (NAA), thermoluminescence dating (TL) an electronic paramagnetic resonance (EPR) to ceramic fragments from the Hatahara archaeological site, located at central Amazon. The elemental concentrations obtained by NAA for 120 ceramic fragments were interpreted by means of cluster analysis and discriminant analysis. The results showed the existence of five distinct ceramic groups. This information, supported by archaeological interpretation, confirm the existence of four distinct occupation Phases at Hatahara site. In order to establish a chronology for the occupations, the ages of three ceramic fragments were determined by TL. The dating of two fragments did not confirm the archaeological interpretation about their occupation Phases. However, the dating of the third fragment allowed the confirmation that it belongs to the Manacapuru Phase. The determination of the burning temperatures of four ceramic fragments was performed by EPR. It was observed that although the analyzed ceramic samples belong to three distinct groups, there was no significant variation on their burning temperatures. (author)

Detection of the Single Nucleotide Polymorphism at Position rs2735940 in the Human Telomerase Reverse Transcriptase Gene by the Introduction of a New Restriction Enzyme Site for the PCR-RFLP Assay.

Science.gov (United States)

Wang, Sihua; Ding, Mingcui; Duan, Xiaoran; Wang, Tuanwei; Feng, Xiaolei; Wang, Pengpeng; Yao, Wu; Wu, Yongjun; Yan, Zhen; Feng, Feifei; Yu, Songcheng; Wang, Wei

2017-09-01

It has been shown that the single nucleotide polymorphism (SNP) of the rs2735940 site in the human telomerase reverse transcriptase ( hTERT ) gene is associated with increased cancer risk. The traditional method to detect SNP genotypes is polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). However, there is a limitation to utilizing PCR-RFLP due to a lack of proper restriction enzyme sites at many polymorphic loci. This study used an improved PCR-RFLP method with a mismatched base for detection of the SNP rs2735940. A new restriction enzyme cutting site was created by created restriction site PCR (CRS-PCR), and in addition, the restriction enzyme Msp I for CRS-PCR was cheaper than other enzymes. We used this novel assay to determine the allele frequencies in 552 healthy Chinese Han individuals, and found the allele frequencies to be 63% for allele C and 37% for allele T In summary, the modified PCR-RFLP can be used to detect the SNP of rs2735940 with low cost and high efficiency. © 2017 by the Association of Clinical Scientists, Inc.

Localized scleroderma: a clinical study at a single center in Korea.

Science.gov (United States)

Noh, Jung Won; Kim, Jinseok; Kim, Jae-Wang

2013-08-01

Localized scleroderma (morphea) is a rare autoimmune disease limited to the skin, characterized by cutaneous fibrosing and obstructive vasculopathy. Localized scleroderma may invade into the subcutaneous fat layer and cause permanent functional disability. Because of its rarity, there have been few clinical surveys of patients with localized scleroderma in Korea. The aim of this study was to elucidate the clinical presentation, serological data, and clinical outcomes of localized scleroderma. This was a retrospective survey conducted by reviewing available medical records during a 7 year-period from 2004 to 2010 in a single medical center in Jeju Island, South Korea. In total 43 patients with localized scleroderma were included. Localized scleroderma occurred primarily in females (female to male ratio 2.6 : 1.0). Most patients were between 10 and 29 years of age and the mean age at diagnosis was 26.2 years. Plaque (51.2%) and linear morphea (37.2%) were most common. No case was associated with systemic scleroderma (systemic sclerosis). The most common site of plaque morphea was the trunk (47.8%). In the linear type, the most common site was head-neck (52.9%). Fluorescent antinuclear antibody was positive in 23.3% of all cases. Treatment included systemic corticosteroids, colchicine, anti-malarial agents, D-penicillamine or intralesional triamcinolone injection. Clinical improvement, including significant and partial response, was seen in only 62.8% of treated patients. Localized scleroderma is a chronic inflammatory condition confined to the skin. In order to exclude other conditions, thorough history taking, physical examination, serologic studies and histopathologic examinations should be conducted. © 2013 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

Nevada Test Site annual site environmental report, 1989

Energy Technology Data Exchange (ETDEWEB)

Wruble, D T; McDowell, E M [eds.

1990-11-01

Prior to 1989 annual reports of environmental monitoring and assessment results for the Nevada Test Site (NTS) were prepared in two separate parts. Onsite effluent monitoring and environmental monitoring results were reported in an onsite report prepared by the US Department of Energy, Nevada Operations Office (DOE/NV). Results of the offsite radiological surveillance program conducted by the US Environmental Protection Agency (EPA), Environmental Monitoring Systems Laboratory, Las Vegas, Nevada, were reported separately by that Agency. Beginning with this 1989 annual Site environmental report for the NTS, these two documents are being combined into a single report to provide a more comprehensive annual documentation of the environmental protection program conducted for the nuclear testing program and other nuclear and non-nuclear activities at the Site. The two agencies have coordinated preparation of this combined onsite and offsite report through sharing of information on environmental releases and meteorological, hydrological, and other supporting data used in dose-estimate calculations. 57 refs., 52 figs., 65 tabs.

Repeated detection of European bat lyssavirus type 2 in dead bats found at a single roost site in the UK.

Science.gov (United States)

Banyard, Ashley C; Johnson, N; Voller, K; Hicks, D; Nunez, A; Hartley, M; Fooks, A R

2009-01-01

In August 2007, European bat lyssavirus type 2 (EBLV-2) was isolated from a Daubenton's bat found at Stokesay Castle. In September 2008, another bat from the same vicinity of Stokesay Castle also tested positive for EBLV-2. This is the first occurrence of repeated detection of EBLV-2 from a single site. Here, we report the detection of low levels of viral RNA in various bat organs by qRT-PCR and detection of viral antigen by immunohistochemistry. We also report sequence data from both cases and compare data with those derived from other EBLV-2 isolations in the UK.

Characterization of Solids in Residual Wastes from Single-Shell Tanks at the Hanford Site, Washington, USA - 9277

International Nuclear Information System (INIS)

Krupka, Kenneth M.; Cantrell, Kirk J.; Schaef, Herbert T.; Arey, Bruce W.; Heald, Steve M.; Deutsch, William J.; Lindberg, Michael J.

2009-01-01

Solid-phase characterization methods have been used in an ongoing study of residual wastes (i.e., waste remaining after final retrieval operations) from the underground single-shell storage tanks 241-C-103, 241-C-106, 241-C-202, 241-C-203, and 241-S-112 at the U.S. Department of Energy's Hanford Site in Washington State. The results of studies completed to date show significant variability in the compositions of those residual wastes and the compositions, morphologies, and crystallinities of the individual phases that make up these wastes. These differences undoubtedly result from the various waste types stored and transferred in and out each tank and the sluicing and retrieval operations used for waste retrieval. Our studies indicate that these residual wastes are chemically-complex assemblages of crystalline and amorphous solids that contain contaminants as discrete phases and/or co-precipitated within oxide phases. Depending on the specific tank, various solids (e.g., gibbsite; boehmite; dawsonite; cancrinite; Fe oxides such as hematite, goethite, and maghemite; rhodochrosite; lindbergite; whewellite; nitratine; and numerous amorphous or poorly crystalline phases) have been identified by X-ray diffraction and scanning electron microscopy/energy dispersive X-ray spectroscopy in residual wastes studied to date. Our studies also show that contact of residual wastes with Ca(OH)2- and CaCO3-saturated aqueous solutions, which were used as surrogates for the compositions of pore-fluid leachants derived from young and aged cements respectively, may alter the compositions of solid phases present in the contacted wastes. Fe oxides/hydroxides have been identified in all residual wastes studied to date. They occur in these wastes as discrete particles, particles intergrown within a matrix of other phases, and surface coatings on other particles or particle aggregates. These Fe oxides/hydroxides typically contain trace concentrations of other transition metals, such Cr, Mn

Single-site robotic cholecystectomy and robotics training: should we start in the junior years?

Science.gov (United States)

Ayabe, Reed I; Parrish, Aaron B; Dauphine, Christine E; Hari, Danielle M; Ozao-Choy, Junko J

2018-04-01

It has become increasingly important to expose surgical residents to robotic surgery as its applications continue to expand. Single-site robotic cholecystectomy (SSRC) is an excellent introductory case to robotics. Resident involvement in SSRC is known to be feasible. Here, we sought to determine whether it is safe to introduce SSRC to junior residents. A total of 98 SSRC cases were performed by general surgery residents between August 2015 and August 2016. Cases were divided into groups based on resident level: second- and third-years (juniors) versus fourth- and fifth-years (seniors). Patient age, gender, race, body mass index, and comorbidities were recorded. The number of prior laparoscopic cholecystectomies completed by participating residents was noted. Outcomes including operative time, console time, rate of conversion to open cholecystectomy, and complication rate were compared between groups. Juniors performed 54 SSRC cases, whereas seniors performed 44. There were no significant differences in patient age, gender, race, body mass index, or comorbidities between the two groups. Juniors had less experience with laparoscopic cholecystectomy. There was no significant difference in mean operative time (92.7 min versus 98.0 min, P = 0.254), console time (48.7 min versus 50.8 min, P = 0.639), or complication rate (3.7% versus 2.3%, P = 0.68) between juniors and seniors. SSRC is an excellent way to introduce general surgery residents to robotics. This study shows that with attending supervision, SSRC is feasible and safe for both junior and senior residents with very low complication rates and no adverse effect on operative time. Copyright © 2017 Elsevier Inc. All rights reserved.

Site study plan for utilities and solid waste, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary draft

International Nuclear Information System (INIS)

1987-06-01

This site plan describes utilities and solid waste studies to be conducted during the characterization of the Deaf Smith County, Texas, site for the US Department of Energy's Salt Repository Project. After utilities and solid waste information needs derived from Federal, State, and local statutes and regulations and the project specifications are briefly described, the site study plan describes the study design and rationale, the field data collection procedures and equipment, and data analysis methods and application of results, the data management strategy, the schedule of field activities, the management of the study, and the study's quality assurance program. The field data collection activities are organized into programs to characterize electrical power, natural gas, communication, water, wastewater sludge, nonradiological solid waste, nonradiological hazardous waste, and low-level radiological waste. These programs include details for the collection of project needs, identification of utilities and solid waste disposal contractor capabilities, and verification of the obtained data. Utilities and solid waste field activities will begin approximately at the time of site access. Utilities and solid waste characterization will be completed within the first year of activity. 29 refs., 6 figs., 2 tabs

Direct Binding to Replication Protein A (RPA)-coated Single-stranded DNA Allows Recruitment of the ATR Activator TopBP1 to Sites of DNA Damage*

Science.gov (United States)

Acevedo, Julyana; Yan, Shan; Michael, W. Matthew

2016-01-01

A critical event for the ability of cells to tolerate DNA damage and replication stress is activation of the ATR kinase. ATR activation is dependent on the BRCT (BRCA1 C terminus) repeat-containing protein TopBP1. Previous work has shown that recruitment of TopBP1 to sites of DNA damage and stalled replication forks is necessary for downstream events in ATR activation; however, the mechanism for this recruitment was not known. Here, we use protein binding assays and functional studies in Xenopus egg extracts to show that TopBP1 makes a direct interaction, via its BRCT2 domain, with RPA-coated single-stranded DNA. We identify a point mutant that abrogates this interaction and show that this mutant fails to accumulate at sites of DNA damage and that the mutant cannot activate ATR. These data thus supply a mechanism for how the critical ATR activator, TopBP1, senses DNA damage and stalled replication forks to initiate assembly of checkpoint signaling complexes. PMID:27129245

Site qualification studies of the UCG-SDB at North Knobs, Wyoming

Energy Technology Data Exchange (ETDEWEB)

Davis, B.E.; Krajewski, S.A.; Ahner, P.F.; Avasthi, J.M.; Dolde, M.E.; Greenman, C.A.; Miranda, J.E.

1979-01-01

The site qualification program for the North Knobs UCG site near Rawlins, Wyoming has been completed. This site will be the location for the field tests of Underground Coal Gasification of Steeply Dipping Beds undertaken by Gulf Research and Development Company for DOE in a cost shared contract. Site characterization included a comprehensive geotechnical analysis along with vegetation, historical, and archeological studies. The G coal seam chosen for these tests is a subbituminous B coal with a true seam thickness of 22 feet and has thin coal benches above and below the main seam. The water table is at 90 feet below the surface. Hydrologic studies have defined the seam as an aquiclude (non-aquifer). The site is deemed restorable to regulatory requirements. Evaluation of this site indicates total acceptability for the three-test program planned by GR and DC.

Feasibility study for siting of a deep repository within the Storuman municipality

International Nuclear Information System (INIS)

1995-01-01

It is SKB's task to gather a broad body of information for the siting of a deep repository for Sweden's spent nuclear fuel and other long-lived radioactive waste. The criteria presented by SKB serve as guidelines for the siting studies. Overviews of siting factors are compiled in general siting studies of all or parts of Sweden. Feasibility studies examine the siting prospects in potentially suitable and interested municipalities. SKB plans to carry out feasibility studies in five to ten municipalities in different parts of the country. General studies and feasibility studies are primarily based on existing material. The feasibility study in Storuman is the first to be conducted. It began during the second half of 1993 with the conclusion of an agreement between the municipality and SKB. SKB has been in charge of the execution of the feasibility study. SKB has been responsible for the summary provided in a status report published in June 1994, as well as for the conclusions and evaluations in this final report. Altogether about 30 reports have been published within the framework of the feasibility study. The purpose of the various studies have been to describe, in as much detail as possible, the prospects for siting a deep repository in the municipality of Storuman, and to shed light on the possible positive and negative consequences of such a siting. The feasibility study has led to a discussion within the municipality and the region concerning the siting of a deep repository. In SKB's opinion, this gives all those concerned ample opportunity to become acquainted with the issues and to assert their interests and present their viewpoints at an early stage. 55 refs

Ipsilateral Dual-Site, Same-Sitting Percutaneous Lung Biopsy: A Feasibility Study

International Nuclear Information System (INIS)

Barnett, Joseph; Tavare, Aniket N.; Khan, Sajid; Saini, Ashish; Creer, Dean D.; Hare, Samanjit S.

2017-01-01

PurposePatients with thoracic malignancies often have more than one site of pulmonary, nodal or pleural disease within one hemithorax. In addition, large heterogeneous lesions may comprise distinct, mixed pathological entities. Histological analysis of these lesions can alter tumour staging and treatment options. We investigated the feasibility, safety and benefit of performing image-guided percutaneous lung biopsy (PLB) of two lesions in the same hemithorax at a single sitting.Materials and MethodsTen consecutive outpatients with two or more potential disease foci within the same hemithorax were analysed over a 15-month period. The mean age of the patients was 66 years (range 46–81 years). Patients underwent CT-guided coaxial 20G   core biopsy of both lesions, with separate coaxial punctures for each lesion. Patients were managed as per established local institution ambulatory lung biopsy protocol using small-calibre Heimlich-valve chest drain (HVCD) to treat significant post-PLB pneumothorax in an outpatient setting. Data regarding lesion characteristics, diagnoses and complications were recorded.ResultsAll 10 patients (n = 20 biopsies, 100% technical success) received informative histological diagnosis on both lesions. This altered management in all cases. Although a high rate of pneumothorax occurred (60%; 6/10), only two of these patients required treatment with HVCD. No other significant complications occurred in those patients with small asymptomatic pneumothoraces or those that required HVCD placement.ConclusionsDual-site lung biopsy, performed as a single procedure, is potentially a safe and effective technique for diagnosing patients with multiple thoracic lesions, and can provide useful staging information to guide patient management.

Ipsilateral Dual-Site, Same-Sitting Percutaneous Lung Biopsy: A Feasibility Study

Energy Technology Data Exchange (ETDEWEB)

Barnett, Joseph; Tavare, Aniket N. [Royal Free London NHS Foundation Trust, Department of Radiology, Barnet Hospital (United Kingdom); Khan, Sajid [Royal Free London NHS Foundation Trust, Department of Respiratory Medicine, Barnet Hospital (United Kingdom); Saini, Ashish [Royal Free London NHS Foundation Trust, Department of Radiology, Barnet Hospital (United Kingdom); Creer, Dean D. [Royal Free London NHS Foundation Trust, Department of Respiratory Medicine, Barnet Hospital (United Kingdom); Hare, Samanjit S., E-mail: samhare@nhs.net [Royal Free London NHS Foundation Trust, Department of Radiology, Barnet Hospital (United Kingdom)

2017-05-15

PurposePatients with thoracic malignancies often have more than one site of pulmonary, nodal or pleural disease within one hemithorax. In addition, large heterogeneous lesions may comprise distinct, mixed pathological entities. Histological analysis of these lesions can alter tumour staging and treatment options. We investigated the feasibility, safety and benefit of performing image-guided percutaneous lung biopsy (PLB) of two lesions in the same hemithorax at a single sitting.Materials and MethodsTen consecutive outpatients with two or more potential disease foci within the same hemithorax were analysed over a 15-month period. The mean age of the patients was 66 years (range 46–81 years). Patients underwent CT-guided coaxial 20G   core biopsy of both lesions, with separate coaxial punctures for each lesion. Patients were managed as per established local institution ambulatory lung biopsy protocol using small-calibre Heimlich-valve chest drain (HVCD) to treat significant post-PLB pneumothorax in an outpatient setting. Data regarding lesion characteristics, diagnoses and complications were recorded.ResultsAll 10 patients (n = 20 biopsies, 100% technical success) received informative histological diagnosis on both lesions. This altered management in all cases. Although a high rate of pneumothorax occurred (60%; 6/10), only two of these patients required treatment with HVCD. No other significant complications occurred in those patients with small asymptomatic pneumothoraces or those that required HVCD placement.ConclusionsDual-site lung biopsy, performed as a single procedure, is potentially a safe and effective technique for diagnosing patients with multiple thoracic lesions, and can provide useful staging information to guide patient management.

Status report on geochemical field results from Atlantic study sites

International Nuclear Information System (INIS)

Wilson, T.R.S.; Thomson, J.; Hydes, D.J.; Colley, S.

1983-01-01

This report summarises the results of preliminary geochemical investigations at three North Atlantic study areas. The two eastern sites, on the Cape Verde abyssal plain (CV2) and east of Great Meteor Seamount (GME) were visited during 1982. The results presented are preliminary. Studies in the western Atlantic, close to the Nares Abyssal Plain study site are more detailed and are presented in a separate paper. The report shows for the first time the relative redox status of the three sites. The differences are unexpectedly large, the most reduced cores being recovered at GME and the most oxidised at CV2. The sporadic nature of Recent sediment accumulation at these sites is also emphasised. In order to place these preliminary results in context their relevance to the production of mathematical system models is discussed in a closing section. The necessity for such models to rest on sound foundations of geochemical understanding is noted. Suggestions on future research priorities are offered for discussion. (author)

First comprehensive inventory of a tropical site for a megadiverse group of insects, the true flies (Diptera)

Science.gov (United States)

Tropical insect biodiversity remains largely unknown for most research sites in the world, due to the overwhelming number of species and lack of focus by taxonomists. Single-site studies are necessary, however to establish baselines for comparative studies across space, and as the basis for ecologic...

Sorption of BTX mixtures to contaminated and uncontaminated site soils

International Nuclear Information System (INIS)

Uchrin, C.G.; Koshy, K.; Wojtenko, I.

1995-01-01

Both adsorption and desorption studies are being performed examining benzene, toluene, and meta-xylene (BTX) as single components, binary mixtures, and trinary mixture onto both existing contaminated soils as well as some uncontaminated reference soils. The contaminated soils were obtained from an oil refinery site and another industrial site in New Jersey. The oil refinery site soil did not exhibit significant amounts of either benzene, toluene or xylene but was contaminated with other compounds while the other industrial site soil was contaminated with toluene among other compounds. The organic carbon content of the soils ranged from 0.14 to 2.91 percent. Preliminary adsorption studies showed BTX to strongly sorb to these soils. The adsorption studies onto the reference soils also demonstrated the effect of organic matter on adsorption. Sequential batch desorption studies show the BTX to desorb quickly, reaching equilibrium within 48 hours. Long-term uptake and release were not noted with these soil/contaminant systems

Study on Site Conditions Based on Topographic Slope

Science.gov (United States)

Wu, X.; Wang, X.; Yuan, X.; Chen, M.; Dou, A.

2018-04-01

The travel-time averaged shear-wave velocity to a depth of 30m (Vs30) below the Earth's surface is widely used to classify sites in many building codes. Vs30 is also used to estimate site classification in recent ground-motion prediction equations (GMPEs), and the distribution of Vs30 has been mapped in a region or country. An alternative method has recently been proposed for evaluating global seismic site conditions or Vs30, from the SRTM (Shuttle Radar Topography Mission) DEMs (digital elevation models). The basic premise of the method is that the topographic slope can be used as a reliable proxy for Vs30 in the absence of geologically and geotechnically based site-condition maps through correlations between Vs30 measurements and topographic gradient. Here, we use different resolutions (3 arcsec, 30 arcsec) DEM data to get Vs30 data separately, analyze and compare the difference of Vs30 data and site conditions obtained from different resolution DEM data. Shandong Province in eastern China and Sichuan Province in Western China are studied respectively. It is found that the higher resolution data is better at defining spatial topographic features than the 30c data, but less improvement in its correlation with Vs30.

STUDY ON SITE CONDITIONS BASED ON TOPOGRAPHIC SLOPE

Directory of Open Access Journals (Sweden)

X. Wu

2018-04-01

Full Text Available The travel-time averaged shear-wave velocity to a depth of 30m (Vs30 below the Earth’s surface is widely used to classify sites in many building codes. Vs30 is also used to estimate site classification in recent ground-motion prediction equations (GMPEs, and the distribution of Vs30 has been mapped in a region or country. An alternative method has recently been proposed for evaluating global seismic site conditions or Vs30, from the SRTM (Shuttle Radar Topography Mission DEMs (digital elevation models. The basic premise of the method is that the topographic slope can be used as a reliable proxy for Vs30 in the absence of geologically and geotechnically based site-condition maps through correlations between Vs30 measurements and topographic gradient. Here, we use different resolutions (3 arcsec, 30 arcsec DEM data to get Vs30 data separately, analyze and compare the difference of Vs30 data and site conditions obtained from different resolution DEM data. Shandong Province in eastern China and Sichuan Province in Western China are studied respectively. It is found that the higher resolution data is better at defining spatial topographic features than the 30c data, but less improvement in its correlation with Vs30.

Feasibility study for siting of a deep repository within the Storuman municipality

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-01-01

It is SKB`s task to gather a broad body of information for the siting of a deep repository for Sweden`s spent nuclear fuel and other long-lived radioactive waste. The criteria presented by SKB serve as guidelines for the siting studies. Overviews of siting factors are compiled in general siting studies of all or parts of Sweden. Feasibility studies examine the siting prospects in potentially suitable and interested municipalities. SKB plans to carry out feasibility studies in five to ten municipalities in different parts of the country. General studies and feasibility studies are primarily based on existing material. The feasibility study in Storuman is the first to be conducted. It began during the second half of 1993 with the conclusion of an agreement between the municipality and SKB. SKB has been in charge of the execution of the feasibility study. SKB has been responsible for the summary provided in a status report published in June 1994, as well as for the conclusions and evaluations in this final report. Altogether about 30 reports have been published within the framework of the feasibility study. The purpose of the various studies have been to describe, in as much detail as possible, the prospects for siting a deep repository in the municipality of Storuman, and to shed light on the possible positive and negative consequences of such a siting. The feasibility study has led to a discussion within the municipality and the region concerning the siting of a deep repository. In SKB`s opinion, this gives all those concerned ample opportunity to become acquainted with the issues and to assert their interests and present their viewpoints at an early stage. 55 refs.

SUPERFUND TREATABILITY CLEARINGHOUSE: SOIL STABILIZATION PILOT STUDY, UNITED CHROME NPL SITE PILOT STUDY AND HEALTH AND SAFETY PROGRAM, UNITED CHROME NPL SITE PILOT STUDY

Science.gov (United States)

This document is a project plan for a pilot study at the United Chrome NPL site, Corvallis, Oregon and includes the health and safety and quality assurance/quality control plans. The plan reports results of a bench-scale study of the treatment process as iieasured by the ...

Introduction of a potent single-donor fibrin glue for vascular anastomosis: An animal study

Directory of Open Access Journals (Sweden)

Mehdi Rasti Ardakani

2012-01-01

Full Text Available Background: Vascular anastomosis is considered as a difficult surgical procedure. Although different alternative methods have been tried to tackle these difficulties, none were found to be successful. Commercial fibrin glue has recently been used for vascular anastomosis. However, it did not gain popularity due to some limitations such as low tensile strength, rapid removal by the immune system, and risk of transmission of blood-borne viral infections. In this article, we presented a novel method for producing single-donor human fibrin glue and determined its success rate for vascular anastomosis in an animal model. Materials ans Methods : In this study, 3 mL of single-donor fibrin sealant was prepared from 150 mL of whole blood containing 50-70 mg/mL of fibrinogen. The study was performed on 10 dogs and 5 cats. After transection of the carotid artery, both ends were anastomosed by means of 3-4 sutures (Prolene 8-0. The suture line was then sealed with one layer of the new fibrin sealant. After 3-8 weeks, the site of anastomosis was evaluated angiographically and morphologically for healing and possible complications such as thrombosis or aneurysm. Results: In evaluations 3 weeks after the surgery, all arterial anastomoses were patent in dogs, but some degree of subintimal hyperplasia was noted. After 8 weeks, all anastomoses were patent and the degree of subintimal hyperplasia was decreased. In cats on the other hand, after 4 weeks, all anastomoses were patent and subintimal hyperplasia was absent. Conclusions: Single-donor fibrin glue was a quite reliable and practical alternative to minimize suturing and therefore operative time in our animal model. This sealant can easily be obtained from the patient′s whole blood. Its application in humans would require further studies.

YUCCA MOUNTAIN SITE DESCRIPTION

International Nuclear Information System (INIS)

Simmons, A.M.

2004-01-01

The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, because of its thick unsaturated zone, its arid to semiarid climate, and the existence of a rock type that would support excavation of stable openings. In 1987, the United States Congress directed that Yucca Mountain be the only site characterized to evaluate its suitability for development of a geologic repository for high-level radioactive waste and spent nuclear fuel

Studies on site characterization methodologies for high level radioactive waste disposal

International Nuclear Information System (INIS)

Wang Ju; Guo Yonghai; Chen Weiming

2008-01-01

This paper presents the final achievement of the project 'Studies of Site-specific Geological Environment for High Level Waste Disposal and Performance Assessment Methodology, Part Ⅰ: Studies on Site Characterization Methodologies for High Level Radioactive Waste Disposal', which is a 'Key Scientific and Technological Pre-Research Project for National Defense' during 2001-2005. The study area is Beishan area, Gansu Province, NW China--the most potential site for China's underground research laboratory and high level radioactive waste repository. The boreholes BS01, BS2, BS03 and BS04 drilled in fractured granite media in Beishan are used to conduct comprehensive studies on site characterization methodologies, including: bore hole drilling method, in situ measurement methods of hydrogeological parameters, underground water sampling technology, hydrogeochemical logging method, geo-stress measurement method, acoustic borehole televiewer measurement method, borehole radar measurement method, fault stability evaluation methods and rock joint evaluation method. The execution of the project has resulted in the establishment of an 'Integrated Methodological System for Site Characterization in Granite Site for High Level Radioactive Waste Repository' and the 8 key methodologies for site characterization: bore hole drilling method with minimum disturbance to rock mass, measurement method for hydrogeological parameters of fracture granite mass, in situ groundwater sampling methods from bore holes in fractured granite mass, fracture measurement methods by borehole televiewer and bore radar system, hydrogeochemical logging, low permeability measurement methods, geophysical methods for rock mass evaluation, modeling methods for rock joints. Those methods are comprehensive, advanced, innovative, practical, reliable and of high accuracy. The comprehensive utilization of those methods in granite mass will help to obtain systematic parameters of

Comparative Study of Phase Transformation in Single-Crystal Germanium during Single and Cyclic Nanoindentation

Directory of Open Access Journals (Sweden)

Koji Kosai

2017-11-01

Full Text Available Single-crystal germanium is a semiconductor material which shows complicated phase transformation under high pressure. In this study, new insight into the phase transformation of diamond-cubic germanium (dc-Ge was attempted by controlled cyclic nanoindentation combined with Raman spectroscopic analysis. Phase transformation from dc-Ge to rhombohedral phase (r8-Ge was experimentally confirmed for both single and cyclic nanoindentation under high loading/unloading rates. However, compared to single indentation, double cyclic indentation with a low holding load between the cycles caused more frequent phase transformation events. Double cyclic indentation caused more stress in Ge than single indentation and increased the possibility of phase transformation. With increase in the holding load, the number of phase transformation events decreased and finally became less than that under single indentation. This phenomenon was possibly caused by defect nucleation and shear accumulation during the holding process, which were promoted by a high holding load. The defect nucleation suppressed the phase transformation from dc-Ge to r8-Ge, and shear accumulation led to another phase transformation pathway, respectively. A high holding load promoted these two phenomena, and thus decreased the possibility of phase transformation from dc-Ge to r8-Ge.

EPR and optical absorption study of Cu{sup 2+} doped lithium sulphate monohydrate (LSMH) single crystals

Energy Technology Data Exchange (ETDEWEB)

Sheela, K. Juliet; Subramanian, P., E-mail: psubramaniangri@gmail.com [Department of Physics, Gandhigram Rural Institute-Deemed University, Gandhigram, Dindigul-624302, Tamilnadu (India); Krishnan, S. Radha; Shanmugam, V. M. [CSIR-Central Electrochemical Research Institute, Karaikudi-63006, Tamilnadu (India)

2016-05-23

EPR study of Cu{sup 2+} doped NLO active Lithium Sulphate monohydrate (Li{sub 2}SO{sub 4.}H{sub 2}O) single crystals were grown successfully by slow evaporation method at room temperature. The principal values of g and A tensors indicate existence of orthorhombic symmetry around the Cu{sup 2+} ion. From the direction cosines of g and A tensors, the locations of Cu{sup 2+} in the lattice have been identified as interstitial site. Optical absorption confirms the rhombic symmetry and ground state wave function of the Cu{sup 2+} ion in a lattice as d{sub x2-y2}.

1H nuclear magnetic resonance studies of the conformation of an ATP analogue at the active site of Na,K-ATPase from kidney medulla

International Nuclear Information System (INIS)

Stewart, J.M.M.; Grisham, C.M.

1988-01-01

1 H nuclear magnetic relaxation measurements have been used to determine the three-dimensional conformation of an ATP analogue, Co(NH 3 ) 4 ATP, at the active site of sheep kidney Na,K-ATPase. Previous studies have shown that Co(NH 4 ) 4 ATP is a competitive inhibitor with respect to MnATP for the Na,K-ATPase and that Mn 2+ bound to a single, high-affinity site on the ATPase can be an effective paramagnetic probe for nuclear relaxation studies of the Na-K-ATPase. From the paramagnetic effect of Mn 2+ bound to the APTase on the longitudinal relaxation rates of the protons of Co(NH 3 ) 4 ATP at the substrate site (at 300 and 361 MHz), Mn-H distances to seven protons on the bound nucleotide were determined. Taken together with previous 31 P nuclear relaxation data, these measurements are consistent with a single nucleotide conformation at the active site. The nucleotide adopts a bent configuration, in which the triphosphate chain lies nearly parallel to the adenine moiety. The glycosidic torsion angle is 35 0 , and the conformation of the ribose ring is slightly N-type. The bound Mn 2+ lies above and in the plane of the adenine ring. The distances from Mn 2+ to N 6 and N 7 are too large for first coordination sphere complexes but are appropriate for second-sphere complexes involving, for example, intervening hydrogen-bonded water molecules. The NMR data also indicate that the structure of the bound ATP analogue is independent of the conformational state of the enzyme

Toward a regional power plant siting method: AEC-Maryland regional siting factors study, FY 1974 progress report

International Nuclear Information System (INIS)

Yaffee, S.L.; Miller, C.A.

1974-11-01

The ''AEC-Maryland Regional Siting Factors Study'' examines the process of siting in a regional context. It is developing an analysis method to delineate candidate areas for siting of several power plant technology packages, including both fossil-fueled and nuclear options. Tools that are being used include simulation modeling, economic and demographic forecasting, spatial analysis, and computer graphics and numerical manipulation. The approach will describe the trade-offs incurred if a power plant is located in one candidate area rather than in another. In FY 1974, a suitability analysis method was developed which uses engineering and environmental parameters to define a level of environmental cost incurred if a segment of land is used to site a specific technology package. (U.S.)

Integrated Framework for Assessing Impacts of CO₂ Leakage on Groundwater Quality and Monitoring-Network Efficiency: Case Study at a CO₂ Enhanced Oil Recovery Site.

Science.gov (United States)

Yang, Changbing; Hovorka, Susan D; Treviño, Ramón H; Delgado-Alonso, Jesus

2015-07-21

This study presents a combined use of site characterization, laboratory experiments, single-well push-pull tests (PPTs), and reactive transport modeling to assess potential impacts of CO2 leakage on groundwater quality and leakage-detection ability of a groundwater monitoring network (GMN) in a potable aquifer at a CO2 enhanced oil recovery (CO2 EOR) site. Site characterization indicates that failures of plugged and abandoned wells are possible CO2 leakage pathways. Groundwater chemistry in the shallow aquifer is dominated mainly by silicate mineral weathering, and no CO2 leakage signals have been detected in the shallow aquifer. Results of the laboratory experiments and the field test show no obvious damage to groundwater chemistry should CO2 leakage occur and further were confirmed with a regional-scale reactive transport model (RSRTM) that was built upon the batch experiments and validated with the single-well PPT. Results of the RSRTM indicate that dissolved CO2 as an indicator for CO2 leakage detection works better than dissolved inorganic carbon, pH, and alkalinity at the CO2 EOR site. The detection ability of a GMN was assessed with monitoring efficiency, depending on various factors, including the natural hydraulic gradient, the leakage rate, the number of monitoring wells, the aquifer heterogeneity, and the time for a CO2 plume traveling to the monitoring well.

Spectroscopic study of interaction between osthole and human serum albumin: Identification of possible binding site of the compound

Energy Technology Data Exchange (ETDEWEB)

Bijari, Nooshin [Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Shokoohinia, Yalda [Department of Pharmacognosy and Biotechnology, Faculty of Pharmacy, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Ashrafi-Kooshk, Mohammad Reza; Ranjbar, Samira; Parvaneh, Shahram [Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Moieni-Arya, Maryam [Student Research Committee, Faculty of Pharmacy, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Khodarahmi, Reza, E-mail: rkhodarahmi@mbrc.ac.ir [Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Department of Pharmacognosy and Biotechnology, Faculty of Pharmacy, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of)

2013-11-15

The studies on the interaction between human serum albumin (HSA) and drugs have been an interesting research field in life science, chemistry and clinical medicine. Osthole possesses a variety of pharmacological activities including anti-tumor, anti-inflammation, anti-seizure, anti-hyperlipidemic and anti-osteoporosis effects. The interaction of osthole with HSA and its binding site in HSA by spectroscopic methods is the subject of this work. By monitoring the intrinsic fluorescence of the single Trp{sub 214} residue and performing site markers displacement measurements, the specific binding of osthole in the vicinity of Sudlow's site I of HSA has been clarified. The changes in the secondary structure of HSA after its complexation with ligand were studied with CD spectroscopy, which indicate that osthole induced only a slight decrease in the helix structural content of the protein. In addition, the mean distance between osthole and HSA fluorophores is estimated to be 4.96 nm using Föster's equation on the basis of the fluorescence energy transfer. Furthermore, the synchronous fluorescence spectra show that the microenvironment of the tryptophan residues does not have obvious changes. Osthole can quench the intrinsic fluorescence of HSA by dynamic quenching, and analysis of the thermodynamic parameters of binding showed that hydrophobic interactions play an important role in the stabilizing of the complex. Increase of protein surface hydrophobicity (PSH) was also observed upon the osthole binding. -- Highlights: • Hydrophobic interactions play an important role in osthole–HSA interaction. • Sudlow's I site is possible binding site of osthole. • Osthole inhibits esterase activity of HSA. • Osthole binding induces no gross protein structural changes.

EPR study of gamma irradiated N-methyl taurine (C 3H 9NO 3S) and sodium hydrogen sulphate monohydrate (NaHSO 3·H 2O) single crystals

Science.gov (United States)

Yıldırım, İlkay; Karabulut, Bünyamin

2011-03-01

EPR study of gamma irradiated C 3H 9NO 3S and NaHSO 3.H 2O single crystals have been carried out at room temperature. There is one site for the radicals in C 3H 9NO 3S and two magnetically distinct sites for the radicals in NaHSO 3. The observed lines in the EPR spectra have been attributed to the species of SO3- and RH radicals for N-methyl taurine, and to the SO3- and OH radicals for sodium hydrogen sulfate monohydrate single crystals. The principal values of the g for SO3-, the hyperfine values of RH and OH proton splitting have been calculated and discussed.

Vasoactive intestinal peptide (VIP) binds to guinea pig peritoneal eosinophils: A single class of binding sites with low affinity and high capacity

International Nuclear Information System (INIS)

Sakakibara, H.; Shima, K.; Takamatsu, J.; Said, S.I.

1990-01-01

VIP binds to specific receptors on lymphocytes and mononuclear cells and exhibits antiinflammatory properties. Eosinophils (Eos) contribute to inflammatory reactions but the regulation of Eos function is incompletely understood. The authors examined the binding of monoradioiodinated VIP, [Tyr( 125 I) 10 ] VIP ( 125 I-VIP), to Eos in guinea pigs. The interaction of 125 i-VIP with Eos was rapid, reversible, saturable and linearly dependent on the number of cells. At equilibrium the binding was competitively inhibited by native peptide or by the related peptide helodermin. Scatchard analysis suggested the presence of a single class of VIP binding sites with a low affinity and a high capacity. In the presence of isobutyl-methylxanthine, VIP, PHI or helodermin did not stimulate cyclic AMP accumulation in intact Eos, while PGE 2 or 1-isoproterenol did. VIP also did not inhibit superoxide anion generation from Eos stimulated by phorbol myristate acetate. The authors conclude that: (1) VIP binds to low-affinity, specific sites on guinea pig peritoneal eosinophils; (2) this binding is not coupled to stimulation of adenylate cyclase; and (3) the possible function of these binding sites is at present unknown

Selective alkane activation with single-site atoms on amorphous support

Science.gov (United States)

Hock, Adam S.; Schweitzer, Neil M.; Miller, Jeffrey T.; Hu, Bo

2015-11-24

The present invention relates generally to catalysts and methods for use in olefin production. More particularly, the present invention relates to novel amorphously supported single-center, Lewis acid metal ions and use of the same as catalysts.

Trade study of leakage detection, monitoring, and mitigation technologies to support Hanford single-shell waste retrieval

International Nuclear Information System (INIS)

Hertzel, J.S.

1996-03-01

The U.S. Department of Energy has established the Tank Waste Remediation System to safely manage and dispose of low-level, high-level, and transuranic wastes currently stored in underground storage tanks at the Hanford Site in Eastern Washington. This report supports the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) Milestone No. M-45-08-T01 and addresses additional issues regarding single-shell tank leakage detection, monitoring, and mitigation technologies and provide an indication of the scope of leakage detection, monitoring, and mitigation activities necessary to support the Tank Waste Remedial System Initial Single-shell Tank Retrieval System project

Surface science of single-site heterogeneous olefin polymerization catalysts

OpenAIRE

Kim, Seong H.; Somorjai, Gabor A.

2006-01-01

This article reviews the surface science of the heterogeneous olefin polymerization catalysts. The specific focus is on how to prepare and characterize stereochemically specific heterogeneous model catalysts for the Ziegler–Natta polymerization. Under clean, ultra-high vacuum conditions, low-energy electron irradiation during the chemical vapor deposition of model Ziegler–Natta catalysts can be used to create a “single-site” catalyst film with a surface structure that produces only isotactic ...

A helping hand: artificial nest site provisioning increases breeding ...

African Journals Online (AJOL)

Common white terns Gygis alba lay a single egg balanced on rocks or branches and consequently are at risk of low nesting success. A novel technique of hollowing out coconut husks and providing artificial nest sites was developed on Cousine Island, Seychelles. Our study aimed to critically assess whether common white ...

Single-cell technologies to study the immune system.

Science.gov (United States)

Proserpio, Valentina; Mahata, Bidesh

2016-02-01

The immune system is composed of a variety of cells that act in a coordinated fashion to protect the organism against a multitude of different pathogens. The great variability of existing pathogens corresponds to a similar high heterogeneity of the immune cells. The study of individual immune cells, the fundamental unit of immunity, has recently transformed from a qualitative microscopic imaging to a nearly complete quantitative transcriptomic analysis. This shift has been driven by the rapid development of multiple single-cell technologies. These new advances are expected to boost the detection of less frequent cell types and transient or intermediate cell states. They will highlight the individuality of each single cell and greatly expand the resolution of current available classifications and differentiation trajectories. In this review we discuss the recent advancement and application of single-cell technologies, their limitations and future applications to study the immune system. © 2015 The Authors. Immunology Published by John Wiley & Sons Ltd.

Olefin polymerization from single site catalysts confined within porous media

Science.gov (United States)

Kasi, Rajeswari M.

Single Site Catalysts (SSCs) have been utilized for olefin polymerization. Altering the metal-ligand architecture in the SSCs, polyolefin properties can be enhanced in a rational manner. This influence of the ligands in the SSC on the property of polyolefins prepared can be referred to as the primary ligand influence. Extending this understanding and subsequent control of the metal-ligand framework to the interaction of SSCs within organic and inorganic supports is vital for the synthesis of polyolefins with tailored properties. The motivation behind this thesis was to explore the support influence on the reactivity of the SSC tethered to a support matrix during ethylene homo and copolymerization. In order to address this question of the support influence on the final polyolefin properties, synthetic routes to covalently bind SSCs on different matrices have been explored. Two distinct supported SSCs have been used to prepare branched polyethylenes. Branched polyethylenes can be prepared by either copolymerization (ethylene and alpha-olefin) or oligomerization/copolymerization processes (ethylene and in situ generated alpha-olefin). Synthetic routes to prepare precursor catalysts to Constrained Geometry Catalysts (CGCs) by silyl elimination chemistry have been developed (Chapter 2). Efficient synthetic protocols to assemble CGCs on aminomethylpolysytrene matrices (Chapter 3) and amine-functionalized mesoporous silica (Chapter 4) are also reported. These supported catalysts, with appropriate cocatalysts have been used to prepare ethylene homo and copolymers, the polymer thermal properties and microstructures were analyzed by various analytical techniques. Branched polyethylenes (LLDPE) can be prepared by copolymerization chemistry. It has been observed is that the influence of the support is seen in the production of lower crystalline forms of high density polyethylene (HDPE, 20--50% crystalline), while homogeneous polymerization of analogous soluble CGCs afford HDPE

Chopper GEN2 + Glyphosate efficacy for height classes of hardwood sprouts recolonizing six clearcut pine sites

Science.gov (United States)

Jimmie Yeiser; Andrew Ezell

2015-01-01

The purpose of this study was to assess sprout size as a determinant of subsequent control by a standard, single rate of imazapyr +glyphosate applied during site preparation. All study sites were in the hilly upper coastal plain of Mississippi (Winston or Oktibbeha Counties) or Louisiana (Sabine or Winn Parishes) and supported loblolly pine (Pinus taeda L.) plantations...

Site-Based Services for Residents of Single-Room Occupancy Hotels.

Science.gov (United States)

Shepard, Melanie

1997-01-01

Describes an evaluation of an innovative site-based service program, the Growth and Achievement Program (GAP). Results show that GAP clients had significantly higher gain scores than did the comparison group and were less likely to rely on public financial assistance as their primary source of income. (RJM)

Seismic hazard for the Savannah River Site: A comparative evaluation of the EPRI and LLNL assessments

International Nuclear Information System (INIS)

Wingo, H.E.

1992-01-01

This report was conducted to: (1) develop an understanding of causes for the vast differences between the two comprehensive studies, and (2) using a methodology consistent with the reconciled methods employed in the two studies, develop a single seismic hazard for the Savannah River Site suitable for use in seismic probabilistic risk assessments with emphasis on the K Reactor. Results are presented for a rock site which is a typical because detailed evaluations of soil characteristics at the K Reactor are still in progress that account for the effects of a soil stablizing grouting program. However when the soils analysis is completed, the effects of soils can be included with this analysis with the addition of a single factor that will decrease slightly the seismic hazard for a rock site

Radionuclide migration studies at the Nevada Test Site

International Nuclear Information System (INIS)

Thompson, J.L.

1989-01-01

The United States government routinely tests nuclear devices at the Nevada Test Site (NTS) in southern Nevada. A significant amount of radioactive material exists underground at the NTS with no containers or engineered barriers to inhibit its subsequent migration. The Department of Energy has sponsored for many years a research program on radionuclide movement in the geologic media at this location. Goals of this research program are to measure the extent of movement of radionuclides away from underground explosion sites and to determine the mechanisms by which such movement occurs. This program has acquired significance in another aspect of nuclear waste management because of the Yucca Mountain Project. Yucca Mountain at the NTS is being intensively studied as the possible site for a mined repository for high level nuclear waste. The NTS provides a unique setting for field studies concerning radionuclide migration; there is the potential for greatly increasing our knowledge of the behavior of radioactive materials in volcanogenic media. This review summarizes some of the significant findings made under this research program at the NTS and identifies reports in which the details of the research may be found. 36 refs., 4 figs

Production of propylene from 1-butene on highly active "bi-functional single active site" catalyst: Tungsten carbene-hydride supported on alumina

KAUST Repository

Mazoyer, Etienne

2011-12-02

1-Butene is transformed in a continuous flow reactor over tungsten hydrides precursor W-H/Al2O3, 1, giving a promising yield into propylene at 150 °C and different pressures. Tungsten carbene-hydride single active site operates as a "bi-functional catalyst" through 1-butene isomerization on W-hydride and 1-butene/2-butenes cross-metathesis on W-carbene. This active moiety is generated in situ at the initiation steps by insertion of 1-butene on tungsten hydrides precursor W-H/Al2O3, 1 followed by α-H and β-H abstraction. © 2011 American Chemical Society.

Study of single W bosons at JLC

International Nuclear Information System (INIS)

Arogancia, Dennis C.; Sanchez, Allister Levi C.; Magallanes, Jingle B.; Gooc, Hermogenes C.; Bacala, Angelina M.; Fujii, Keisuke; Miyamoto, Akiya

2001-01-01

Single W bosons are studied through computer simulation using the process e + e - → e + ν e W - where it decays into two hadronic jets. This study focuses of the measurement of W boson mass with and without beamstrahlung and initial state radiation (ISR) effects. The JLC Study Framework (JSF) is employed for this purpose. The center-of-mass energy is set at 500 GeV. (author)

Case study: Montclair/West Orange and Glen Ridge Radium Superfund sites

International Nuclear Information System (INIS)

Pezzella, R.; Seppi, P.; Watson, D.

1994-01-01

The Montclair/West Orange and Glen Ridge Radium Sites are located 12 miles west of New York City in three residential communities in Essex County, New Jersey. The sites are contaminated with waste materials from a local radium processing facility which ceased operations in 1926. Houses were subsequently constructed on or near the radium waste disposal areas. The waste material was also used as backfill, which caused contamination to be spread randomly over the communities. There are 769 properties between four townships that comprise the Superfund sites. The Environmental Protection Agency (EPA) conducted an aerial survey in 1981 which identified the boundaries of the sites. In 1985, the New Jersey Department of Environmental Protection (NJDEP) began a pilot study to examine the feasibility of excavation and off-site disposal of contaminated material as a permanent solution. The study was interrupted when the permit for the disposal site was revoked by the state of Nevada. Since 1990 field testing has been completed on over 725 properties and remediation and restoration has been completed on 75 properties

Evidence that adaptation in Drosophila is not limited by mutation at single sites.

Directory of Open Access Journals (Sweden)

Talia Karasov

2010-06-01

Full Text Available Adaptation in eukaryotes is generally assumed to be mutation-limited because of small effective population sizes. This view is difficult to reconcile, however, with the observation that adaptation to anthropogenic changes, such as the introduction of pesticides, can occur very rapidly. Here we investigate adaptation at a key insecticide resistance locus (Ace in Drosophila melanogaster and show that multiple simple and complex resistance alleles evolved quickly and repeatedly within individual populations. Our results imply that the current effective population size of modern D. melanogaster populations is likely to be substantially larger (> or = 100-fold than commonly believed. This discrepancy arises because estimates of the effective population size are generally derived from levels of standing variation and thus reveal long-term population dynamics dominated by sharp--even if infrequent--bottlenecks. The short-term effective population sizes relevant for strong adaptation, on the other hand, might be much closer to census population sizes. Adaptation in Drosophila may therefore not be limited by waiting for mutations at single sites, and complex adaptive alleles can be generated quickly without fixation of intermediate states. Adaptive events should also commonly involve the simultaneous rise in frequency of independently generated adaptive mutations. These so-called soft sweeps have very distinct effects on the linked neutral polymorphisms compared to the standard hard sweeps in mutation-limited scenarios. Methods for the mapping of adaptive mutations or association mapping of evolutionarily relevant mutations may thus need to be reconsidered.

Regulatory Closure Options for the Residue in the Hanford Site Single-Shell Tanks

Energy Technology Data Exchange (ETDEWEB)

Cochran, J.R. Shyr, L.J.

1998-10-05

Liquid, mixed, high-level radioactive waste (HLW) has been stored in 149 single-shell tanks (SSTS) located in tank farms on the U.S. Department of Energy's (DOE's) Hanford Site. The DOE is developing technologies to retrieve as much remaining HLW as technically possible prior to physically closing the tank farms. In support of the Hanford Tanks Initiative, Sandia National Laboratories has addressed the requirements for the regulatory closure of the radioactive component of any SST residue that may remain after physical closure. There is significant uncertainty about the end state of each of the 149 SSTS; that is, the nature and amount of wastes remaining in the SSTS after retrieval is uncertain. As a means of proceeding in the face of these uncertainties, this report links possible end-states with associated closure options. Requirements for disposal of HLW and low-level radioactive waste (LLW) are reviewed in detail. Incidental waste, which is radioactive waste produced incidental to the further processing of HLW, is then discussed. If the low activity waste (LAW) fraction from the further processing of HLW is determined to be incidental waste, then DOE can dispose of that incidental waste onsite without a license from the U.S. Nuclear Regulatory Commissions (NRC). The NRC has proposed three Incidental Waste Criteria for determining if a LAW fraction is incidental waste. One of the three Criteria is that the LAW fraction should not exceed the NRC's Class C limits.

Regulatory Closure Options for the Residue in the Hanford Site Single-Shell Tanks

International Nuclear Information System (INIS)

Cochran, J.R.; Shyr, L.J.

1998-01-01

Liquid, mixed, high-level radioactive waste (HLW) has been stored in 149 single-shell tanks (SSTS) located in tank farms on the U.S. Department of Energy's (DOE's) Hanford Site. The DOE is developing technologies to retrieve as much remaining HLW as technically possible prior to physically closing the tank farms. In support of the Hanford Tanks Initiative, Sandia National Laboratories has addressed the requirements for the regulatory closure of the radioactive component of any SST residue that may remain after physical closure. There is significant uncertainty about the end state of each of the 149 SSTS; that is, the nature and amount of wastes remaining in the SSTS after retrieval is uncertain. As a means of proceeding in the face of these uncertainties, this report links possible end-states with associated closure options. Requirements for disposal of HLW and low-level radioactive waste (LLW) are reviewed in detail. Incidental waste, which is radioactive waste produced incidental to the further processing of HLW, is then discussed. If the low activity waste (LAW) fraction from the further processing of HLW is determined to be incidental waste, then DOE can dispose of that incidental waste onsite without a license from the U.S. Nuclear Regulatory Commissions (NRC). The NRC has proposed three Incidental Waste Criteria for determining if a LAW fraction is incidental waste. One of the three Criteria is that the LAW fraction should not exceed the NRC's Class C limits

Studies on Labour Safety in Construction Sites

Directory of Open Access Journals (Sweden)

S. Kanchana

2015-01-01

Full Text Available Construction industry has accomplished extensive growth worldwide particularly in past few decades. For a construction project to be successful, safety of the structures as well as that of the personnel is of utmost importance. The safety issues are to be considered right from the design stage till the completion and handing over of the structure. Construction industry employs skilled and unskilled labourers subject to construction site accidents and health risks. A proper coordination between contractors, clients, and workforce is needed for safe work conditions which are very much lacking in Indian construction companies. Though labour safety laws are available, the numerous accidents taking place at construction sites are continuing. Management commitment towards health and safety of the workers is also lagging. A detailed literature study was carried out to understand the causes of accidents, preventive measures, and development of safe work environment. This paper presents the results of a questionnaire survey, which was distributed among various categories of construction workers in Kerala region. The paper examines and discusses in detail the total working hours, work shifts, nativity of the workers, number of accidents, and type of injuries taking place in small and large construction sites.

Studies on Labour Safety in Construction Sites

Science.gov (United States)

Kanchana, S.; Sivaprakash, P.; Joseph, Sebastian

2015-01-01

Construction industry has accomplished extensive growth worldwide particularly in past few decades. For a construction project to be successful, safety of the structures as well as that of the personnel is of utmost importance. The safety issues are to be considered right from the design stage till the completion and handing over of the structure. Construction industry employs skilled and unskilled labourers subject to construction site accidents and health risks. A proper coordination between contractors, clients, and workforce is needed for safe work conditions which are very much lacking in Indian construction companies. Though labour safety laws are available, the numerous accidents taking place at construction sites are continuing. Management commitment towards health and safety of the workers is also lagging. A detailed literature study was carried out to understand the causes of accidents, preventive measures, and development of safe work environment. This paper presents the results of a questionnaire survey, which was distributed among various categories of construction workers in Kerala region. The paper examines and discusses in detail the total working hours, work shifts, nativity of the workers, number of accidents, and type of injuries taking place in small and large construction sites. PMID:26839916

Phase 1 RCRA Facility Investigation and Corrective Measures Study Work Plan for Single Shell Tank Waste Management Areas

International Nuclear Information System (INIS)

ROGERS, P.M.

2000-01-01

This document is the master work plan for the Resource Conservation and Recovery Act of 1976 (RCRA) for single-shell tank (SST) farms at the Hanford Site. Evidence indicates that releases at four of the seven SST waste management areas have impacted

Phase 1 RCRA Facility Investigation and Corrective Measures Study Work Plan for Single Shell Tank Waste Management Areas

Energy Technology Data Exchange (ETDEWEB)

ROGERS, P.M.

2000-06-01

This document is the master work plan for the Resource Conservation and Recovery Act of 1976 (RCRA) for single-shell tank (SST) farms at the Hanford Site. Evidence indicates that releases at four of the seven SST waste management areas have impacted.

Single well techniques

International Nuclear Information System (INIS)

Drost, W.

1983-01-01

The single well technique method includes measurement of parameters of groundwater flow in saturated rock. For determination of filtration velocity the dilution of radioactive tracer is measured, for direction logging the collimeter is rotated in the probe linked with the compass. The limiting factor for measurement of high filtration velocities is the occurrence of turbulent flow. The single well technique is used in civil engineering projects, water works and subsurface drainage of liquid waste from disposal sites. The radioactive tracer method for logging the vertical fluid movement in bore-holes is broadly used in groundwater survey and exploitation. (author)

YUCCA MOUNTAIN SITE DESCRIPTION

Energy Technology Data Exchange (ETDEWEB)

A.M. Simmons

2004-04-16

The ''Yucca Mountain Site Description'' summarizes, in a single document, the current state of knowledge and understanding of the natural system at Yucca Mountain. It describes the geology; geochemistry; past, present, and projected future climate; regional hydrologic system; and flow and transport within the unsaturated and saturated zones at the site. In addition, it discusses factors affecting radionuclide transport, the effect of thermal loading on the natural system, and tectonic hazards. The ''Yucca Mountain Site Description'' is broad in nature. It summarizes investigations carried out as part of the Yucca Mountain Project since 1988, but it also includes work done at the site in earlier years, as well as studies performed by others. The document has been prepared under the Office of Civilian Radioactive Waste Management quality assurance program for the Yucca Mountain Project. Yucca Mountain is located in Nye County in southern Nevada. The site lies in the north-central part of the Basin and Range physiographic province, within the northernmost subprovince commonly referred to as the Great Basin. The basin and range physiography reflects the extensional tectonic regime that has affected the region during the middle and late Cenozoic Era. Yucca Mountain was initially selected for characterization, in part, because of its thick unsaturated zone, its arid to semiarid climate, and the existence of a rock type that would support excavation of stable openings. In 1987, the United States Congress directed that Yucca Mountain be the only site characterized to evaluate its suitability for development of a geologic repository for high-level radioactive waste and spent nuclear fuel.

Laparoscopic single-port ovariectomy and gastropexy in dogs.

Science.gov (United States)

Gandini, M; Giusto, G

2016-11-01

In this study single-port percutaneous laparoscopic gastropexy in dogs using barbed suture material in combination with ovariectomy is described. A single port preventive gastropexy was performed in 6 female German shepherds in combination with ovariectomy using a laparoscope. Surgery time, intraoperative, postoperative and follow up complications were recorded. In this study median surgery time in clinical cases was 73 minutes (range 66-79). The only difficulty reported was visualization of a proper site for gastropexy on the stomach. No complications and/or episodes of gastric volvulus were detected at a 3-month minimum follow-up. The proposed technique provides an effective and minimally invasive approach to ovariectomy and preventive gastropexy in dogs.

Comparison between magnetic anchoring and guidance system camera-assisted laparoendoscopic single-site surgery nephrectomy and conventional laparoendoscopic single-site surgery nephrectomy in a porcine model: focus on ergonomics and workload profiles.

Science.gov (United States)

Han, Woong Kyu; Tan, Yung K; Olweny, Ephrem O; Yin, Gang; Liu, Zhuo-Wei; Faddegon, Stephen; Scott, Daniel J; Cadeddu, Jeffrey A

2013-04-01

To compare surgeon-assessed ergonomic and workload demands of magnetic anchoring and guidance system (MAGS) laparoendoscopic single-site surgery (LESS) nephrectomy with conventional LESS nephrectomy in a porcine model. Participants included two expert and five novice surgeons who each performed bilateral LESS nephrectomy in two nonsurvival animals using either the MAGS camera or conventional laparoscope. Task difficulty and workload demands of the surgeon and camera driver were assessed using the validated National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire. Surgeons were also asked to score 6 parameters on a Likert scale (range 1=low/easy to 5=high/hard): procedure-associated workload, ergonomics, technical challenge, visualization, accidental events, and instrument handling. Each step of the nephrectomy was also timed and instrument clashing was quantified. Scores for each parameter on the Likert scale were significantly lower for MAGS-LESS nephrectomy. Mean number of internal and external clashes were significantly lower for the MAGS camera (pNASA-TLX workload ratings by the surgeon and camera driver showed that MAGS resulted in a significantly lower workload than the conventional laparoscope during LESS nephrectomy (p<0.05). The use of the MAGS camera during LESS nephrectomy lowers the task workload for both the surgeon and camera driver when compared to conventional laparoscope use. Subjectively, it appears to also improve surgeons' impressions of ergonomics and technical challenge. Pending approval for clinical use, further evaluation in the clinical setting is warranted.

Contaminant transport modeling studies of Russian sites

International Nuclear Information System (INIS)

Tsang, Chin-Fu

1993-01-01

Lawrence Berkeley Laboratory (LBL) established mechanisms that promoted cooperation between U.S. and Russian scientists in scientific research as well as environmental technology transfer. Using Russian experience and U.S technology, LBL developed approaches for field investigations, site evaluation, waste disposal, and remediation at Russian contaminated sites. LBL assessed a comprehensive database as well as an actual, large-scale contaminated site to evaluate existing knowledge of and test mathematical models used for the assessment of U.S. contaminated sites

Single-port laparoscopic myomectomy using a new single-port transumbilical morcellation system: initial clinical study.

Science.gov (United States)

Kim, Yong-Wook; Park, Byung-Joon; Ro, Duck-Yeong; Kim, Tae-Eung

2010-01-01

To evaluate the feasibility of single-port laparoscopic myomectomy with transumbilical morcellation and suturing. Continuing prospective study (Canadian Task Force classification II-3). University hospital. Fifteen patients who underwent single-port laparoscopic myomectomy between September 2008 and October 2009 to remove single or multiple uterine myomas, at least 1 in each patient measuring greater than 4 cm in diameter. All single-port laparoscopic myomectomy procedures were performed by a single surgeon (Dr. Y.W. Kim). Myomas were extracted transumbilically by cutting the myomas into smaller pieces with a knife or a conventional electromechanical morcellator. After making a single 1.5- to 2.0-cm umbilical incision, the single-port system, created with a wound retractor and a surgical glove, was inserted. All operations were performed using conventional rigid straight laparoscopic instruments. Laparoscopic suturing was performed in intramural myomas and some subserosal myomas. Patient mean (SD; range) age was 38.3 (5.6; 29-49) years. The number of myomas per patient was 1.6 (1.4; 1-6). The diameter of the largest myomas was 6.1 (1.5; 4.2-9.6) cm. In 4 patients, only a knife was required for transumbilical extraction of myomas, and in 11 patients, transumbilical morcellation with an electromechanical morcellator with or without a knife was used. Transumbilical drainage tubes were inserted into the pelvic cavity in 11 of 15 patients. Operative time was 96.7 (33.8; 35-150) minutes. The decrease in postoperative hemoglobin concentration was 1.8 (1.2; 0.4-3.6) g/dL. During the operations, no patients required blood transfusion. No patients developed postoperative fever. Neither bowel injury nor urinary tract injury occurred in any patient. The postoperative hospital stay was 3.1 (0.8; 2-4) days. Single-port transumbilical morcellation using a conventional electromechanical morcellator with or without a knife is feasible. Single-port laparoscopic myomectomy is an

Single ferromagnetic fluctuations in UCoGe revealed by 73Ge- and 59Co-NMR studies

Science.gov (United States)

Manago, Masahiro; Ishida, Kenji; Aoki, Dai

2018-02-01

73Ge and 59Co nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) measurements have been performed on a 73Ge-enriched single-crystalline sample of the ferromagnetic superconductor UCoGe in the paramagnetic state. The 73Ge NQR parameters deduced from NQR and NMR are close to those of another isostructural ferromagnetic superconductor URhGe. The Knight shifts of the Ge and Co sites are well scaled to each other when the magnetic field is parallel to the b or c axis. The hyperfine coupling constants of Ge are estimated to be close to those of Co. The large difference of spin susceptibilities between the a and b axes could lead to the different response of the superconductivity and ferromagnetism with the field parallel to these directions. The temperature dependence of the nuclear spin-lattice relaxation rates 1 /T1 at the two sites is similar to each other above 5 K. These results indicate that the itinerant U-5 f electrons are responsible for the ferromagnetism in this compound, consistent with previous studies. The similarities and differences in the three ferromagnetic superconductors are discussed.

Single-cell regulome data analysis by SCRAT.

Science.gov (United States)

Ji, Zhicheng; Zhou, Weiqiang; Ji, Hongkai

2017-09-15

Emerging single-cell technologies (e.g. single-cell ATAC-seq, DNase-seq or ChIP-seq) have made it possible to assay regulome of individual cells. Single-cell regulome data are highly sparse and discrete. Analyzing such data is challenging. User-friendly software tools are still lacking. We present SCRAT, a Single-Cell Regulome Analysis Toolbox with a graphical user interface, for studying cell heterogeneity using single-cell regulome data. SCRAT can be used to conveniently summarize regulatory activities according to different features (e.g. gene sets, transcription factor binding motif sites, etc.). Using these features, users can identify cell subpopulations in a heterogeneous biological sample, infer cell identities of each subpopulation, and discover distinguishing features such as gene sets and transcription factors that show different activities among subpopulations. SCRAT is freely available at https://zhiji.shinyapps.io/scrat as an online web service and at https://github.com/zji90/SCRAT as an R package. hji@jhu.edu. Supplementary data are available at Bioinformatics online. © The Author(s) 2017. Published by Oxford University Press.

SSDOnt: An Ontology for Representing Single-Subject Design Studies.

Science.gov (United States)

Berges, Idoia; Bermúdez, Jesus; Illarramendi, Arantza

2018-02-01

Single-Subject Design is used in several areas such as education and biomedicine. However, no suited formal vocabulary exists for annotating the detailed configuration and the results of this type of research studies with the appropriate granularity for looking for information about them. Therefore, the search for those study designs relies heavily on a syntactical search on the abstract, keywords or full text of the publications about the study, which entails some limitations. To present SSDOnt, a specific purpose ontology for describing and annotating single-subject design studies, so that complex questions can be asked about them afterwards. The ontology was developed following the NeOn methodology. Once the requirements of the ontology were defined, a formal model was described in a Description Logic and later implemented in the ontology language OWL 2 DL. We show how the ontology provides a reference model with a suitable terminology for the annotation and searching of single-subject design studies and their main components, such as the phases, the intervention types, the outcomes and the results. Some mappings with terms of related ontologies have been established. We show as proof-of-concept that classes in the ontology can be easily extended to annotate more precise information about specific interventions and outcomes such as those related to autism. Moreover, we provide examples of some types of queries that can be posed to the ontology. SSDOnt has achieved the purpose of covering the descriptions of the domain of single-subject research studies. Schattauer GmbH.

Quantitative autoradiographic distribution of L-[3H]glutamate-binding sites in rat central nervous system

International Nuclear Information System (INIS)

Greenamyre, J.T.; Young, A.B.; Penney, J.B.

1984-01-01

Quantitative autoradiography was used to determine the distribution of L-[3H]glutamate-binding sites in the rat central nervous system. Autoradiography was carried out in the presence of Cl- and Ca2+ ions. Scatchard plots and Hill coefficients of glutamate binding suggested that glutamate was interacting with a single population of sites having a K-D of about 300 nM and a capacity of 14.5 pmol/mg of protein. In displacement studies, ibotenate also appeared to bind to a single class of non-interacting sites with a KI of 28 microM. However, quisqualate displacement of [3H]glutamate binding revealed two well-resolved sites with KIS of 12 nM and 114 microM in striatum. These sites were unevenly distributed, representing different proportions of specific glutamate binding in different brain regions. The distribution of glutamate-binding sites correlated very well with the projection areas of putative glutamatergic pathways. This technique provides an extremely sensitive assay which can be used to gather detailed pharmacological and anatomical information about L-[3H]glutamate binding in the central nervous system

Dynamic usage of transcription start sites within core promoters

DEFF Research Database (Denmark)

Kawaji, Hideya; Frith, Martin C; Katayama, Shintaro

2006-01-01

BACKGROUND: Mammalian promoters do not initiate transcription at single, well defined base pairs, but rather at multiple, alternative start sites spread across a region. We previously characterized the static structures of transcription start site usage within promoters at the base pair level......, based on large-scale sequencing of transcript 5' ends. RESULTS: In the present study we begin to explore the internal dynamics of mammalian promoters, and demonstrate that start site selection within many mouse core promoters varies among tissues. We also show that this dynamic usage of start sites...... is associated with CpG islands, broad and multimodal promoter structures, and imprinting. CONCLUSION: Our results reveal a new level of biologic complexity within promoters--fine-scale regulation of transcription starting events at the base pair level. These events are likely to be related to epigenetic...

Laparoendoscopic single-site surgery (LESS) for the treatment of different urologic pathologies in pediatrics: single-center single-surgeon experience.

Science.gov (United States)

Abdel-Karim, Aly M; Elmissery, Mostafa; Elsalmy, Salah; Moussa, Ahmed; Aboelfotoh, Ahmed

2015-02-01

Recently LESS has been reported as a valid minimally option for treatment of some urologic pathologies in pediatrics. However, the initial reports of pediatric LESS are still limited to case reports and initial case series. This may be due to the inherent technical difficulty of LESS and the currently available LESS instruments. In this report, we present the largest case series of pediatric LESS for treatment of different urologic pathologies in pediatrics. Included in this study are children who had LESS during the period of January 2011 to June 2013. Both Olympus TriPort (Olympus, New York, USA and Advance Surgical Concept, Wicklow, Ireland) and Covedien SILS access port (Covedien, Chicopec, Massachusetts, USA) were used and were inserted through the umbilicus. Exclusion criteria included children less than 3 years old, history of previous transperitoneal abdominal surgery, malignant indications, and complex urogenital congenital anomalies. All LESS procedures were done by a single experienced laparoscopist and data were reviewed retrospectively. Twenty-two children had 39 LESS procedures without conversion to conventional laparoscopy or open surgery. No intraoperative or postoperative complications were reported and no extra-port was added in any of the patients. The following table shows the mean age, operative time, hospital stay, VAS as well as the overall mean of different LESS procedures. In all patients the umbilical scar was invisible and all patients and their parents had high wound satisfaction. At a mean follow up of 18.6 ± 6.4 months, all patients with UPJO had successful repair. Our study included 13 boys with undescended testis who were managed in different ways according to the length of spermatic vessels and the size of the testis. One of the arguments against LESS management of undescended testis is that it requires a 2.5-cm incision, which is collectively larger than a 5-mm camera and two 3-mm working ports of conventional laparoscopy. However

Stretching single fibrin fibers hampers their lysis.

Science.gov (United States)

Li, Wei; Lucioni, Tomas; Li, Rongzhong; Bonin, Keith; Cho, Samuel S; Guthold, Martin

2017-09-15

Blood clots, whose main structural component is a mesh of microscopic fibrin fibers, experience mechanical strain from blood flow, clot retraction and interactions with platelets and other cells. We developed a transparent, striated and highly stretchable substrate made from fugitive glue (a styrenic block copolymer) to investigate how mechanical strain affects lysis of single, suspended fibrin fibers. In this suspended fiber assay, lysis manifested itself by fiber elongation, thickening (disassembly), fraying and collapse. Stretching single fibrin fibers significantly hampered their lysis. This effect was seen in uncrosslinked and crosslinked fibers. Crosslinking (without stretching) also hampered single fiber lysis. Our data suggest that strain is a novel mechanosensitive factor that regulates blood clot dissolution (fibrinolysis) at the single fiber level. At the molecular level of single fibrin molecules, strain may distort, or hinder access to, plasmin cleavage sites and thereby hamper lysis. Fibrin fibers are the major structural component of a blood clot. We developed a highly stretchable substrate made from fugitive glue and a suspended fibrin fiber lysis assay to investigate the effect of stretching on single fibrin fibers lysis. The key findings from our experiments are: 1) Fibers thicken and elongate upon lysis; 2) stretching strongly reduces lysis; 3) this effect is more pronounced for uncrosslinked fibers; and 4) stretching fibers has a similar effect on reducing lysis as crosslinking fibers. At the molecular level, strain may distort plasmin cleavage sites, or restrict access to those sites. Our results suggest that strain may be a novel mechanobiological factor that regulates fibrinolysis. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Site-specific forest-assembly of single-wall carbon nanotubes on electron-beam patterned SiOx/Si substrates

International Nuclear Information System (INIS)

Wei Haoyan; Kim, Sang Nyon; Kim, Sejong; Huey, Bryan D.; Papadimitrakopoulos, Fotios; Marcus, Harris L.

2008-01-01

Based on electron-beam direct writing on the SiO x /Si substrates, favorable absorption sites for ferric cations (Fe 3+ ions) were created on the surface oxide layer. This allowed Fe 3+ -assisted self-assembled arrays of single-wall carbon nanotube (SWNT) probes to be produced. Auger investigation indicated that the incident energetic electrons depleted oxygen, creating more dangling bonds around Si atoms at the surface of the SiO x layer. This resulted in a distinct difference in the friction forces from unexposed regions as measured by lateral force microscopy (LFM). Atomic force microscopy (AFM) affirmed that the irradiated domains absorbed considerably more Fe 3+ ions upon immersion into pH 2.2 aqueous FeCl 3 solution. This rendered a greater yield of FeO(OH)/FeOCl precipitates, primarily FeO(OH), upon subsequent washing with lightly basic dimethylformamide (DMF) solution. Such selective metal-functionalization established the basis for the subsequent patterned forest-assembly of SWNTs as demonstrated by resonance Raman spectroscopy

CO Reduction to CH3OSiMe3: Electrophile-Promoted Hydride Migration at a Single Fe Site.

Science.gov (United States)

Deegan, Meaghan M; Peters, Jonas C

2017-02-22

One of the major challenges associated with developing molecular Fischer-Tropsch catalysts is the design of systems that promote the formation of C-H bonds from H 2 and CO while also facilitating the release of the resulting CO-derived organic products. To this end, we describe the synthesis of reduced iron-hydride/carbonyl complexes that enable an electrophile-promoted hydride migration process, resulting in the reduction of coordinated CO to a siloxymethyl (L n Fe-CH 2 OSiMe 3 ) group. Intramolecular hydride-to-CO migrations are extremely rare, and to our knowledge the system described herein is the first example where such a process can be accessed from a thermally stable M(CO)(H) complex. Further addition of H 2 to L n Fe-CH 2 OSiMe 3 releases CH 3 OSiMe 3 , demonstrating net four-electron reduction of CO to CH 3 OSiMe 3 at a single Fe site.

Site Study Plan for Acoustics, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary draft

International Nuclear Information System (INIS)

1987-06-01

The Acoustics site study plan describes a field program which characterizes existing sound levels, determines the area's sound propagation characteristics, and monitors the project-related sound emissions. The plan describes for each study: the need for the study, study design, data management and use, schedule, and quality assurance requirements. These studies will provide data needed to satisfy requirements contained in, or derived from, the Salt Repository Requirements Document. 37 refs., 9 figs., 3 tabs

Radon levels at the rehabilitated Nabarlek mine site

International Nuclear Information System (INIS)

Tims, S.; Ryan, B.; Martin, P.

1998-01-01

Full text: A high sensitivity radon monitor has now been in continuous operation at the Nabarlek mine site for several months. The pit area can be viewed as a single, extended radon source, which can be used to assess the validity of radon dispersal predictions. The data have been recorded simultaneously with a variety of meteorological parameters, with a view to using correlations between the data sets as a guide for the improvement of dispersion model inputs. The sensitivity of radon concentration to selected parameters will be discussed, as will the future of the study which aims to make additional simultaneous radon measurements at selected locations around the mine site

Radiolabelling of phoneutria nigriventer spider toxin (Tx1): a tool to study its binding site

International Nuclear Information System (INIS)

Santos, Raquel Gouvea dos; Diniz, Carlos Roberto; Nascimento, Marta Cordeiro; Lima, Maria Elena de

1996-01-01

The neurotoxin Tx1, isolated from the venom of the South American spider Phoneutria nigriventer produces tail elevation and spastic paralysis of posterior limbs after intracerebral ventricular injection in mice. Tx1 also produces ileum contraction in bioassay. We have investigated the binding of radioiodinated-Tx1 ( 125 I-Tx1) on the preparation of myenteric plexus-longitudinal muscle membrane from guinea pig ileum (MPLM) as a tool to characterize the interaction of this neurotoxin with its site. The neurotoxin Tx1 was radioiodinated with Na 125 I by the lactoperoxidase method. 125 I-Tx1 specifically binds to a single class of noninteracting binding sites of high affinity (Kd= 3.5 x 10 -10 M) and low capacity (1.2 pmol/mg protein). The specific binding increased in parallel with the protein concentration. In competition experiments the ligands of ionic channels used (sodium, potassium and calcium) did not affect the binding of 125 I-Tx1 to MPLM neither did the cholinergic ligands (hemicholinium-3, hexamethonium, d-tubocurarine and atropine). Another neurotoxin (Tx2-6, one of the isoforms of Tx2 pool) decreased toxin with MPLM and showed that toxin has a specific and saturable binding site in guinea pig ileum and this binding site appears to be related to the Tx2 site. (author)

Single-Incision Transumbilical Surgery (SITUS) versus Single-Port Laparoscopic Surgery and conventional laparoscopic surgery: a prospective randomized comparative study of performance with novices in a dry laboratory.

Science.gov (United States)

Schoenthaler, Martin; Avcil, Tuba; Sevcenco, Sabina; Nagele, Udo; Hermann, Thomas E W; Kuehhas, Franklin E; Shariat, Shahrokh F; Frankenschmidt, Alexander; Wetterauer, Ulrich; Miernik, Arkadiusz

2015-01-01

To evaluate the Single-Incision Transumbilical Surgery (SITUS) technique as compared to an established laparoendoscopic single-site surgery (LESS) technique (Single-Port Laparoscopic Surgery, SPLS) and conventional laparoscopy (CLS) in a surgical simulator model. Sixty-three medical students without previous laparoscopic experience were randomly assigned to one of the three groups (SITUS, SPLS and CLS). Subjects were asked to perform five standardized tasks of increasing difficulty adopted from the Fundamentals of Laparoscopic Surgery curriculum. Statistical evaluation included task completion times and accuracy. Overall performances of all tasks (except precision cutting) were significantly faster and of higher accuracy in the CLS and SITUS groups than in the SPLS group (p = 0.004 to p port-assisted LESS technique such as SPLS. The demonstrated advantages of SITUS may be attributed to a preservation of the basic principles of conventional laparoscopy, such as the use of straight instruments and an adequate degree of triangulation.

Bibliometric studies on single journals: a review

OpenAIRE

Kevin Wan , Utap Anyi; Anuar , N.B.; Zainab, A.N

2009-01-01

This paper covers a total of 82 bibliometric studies on single journals (62 studies cover unique titles) published between 1998 and 2008 grouped into the following fields; Arts, Humanities and Social Sciences (12 items); Medical and Health Sciences (19 items); Sciences and Technology (30 items) and Library and Information Sciences (21 items). Under each field the studies are described in accordance to their geographical location in the following order, United Kingdom, United States and Americ...

Study of single W bosons at JLC

Energy Technology Data Exchange (ETDEWEB)

Arogancia, Dennis C.; Sanchez, Allister Levi C.; Magallanes, Jingle B.; Gooc, Hermogenes C.; Bacala, Angelina M. [Mindanao State Univ., Dept. of Physics, Iligan (Philippines); Fujii, Keisuke; Miyamoto, Akiya [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan)

2001-06-01

Single W bosons are studied through computer simulation using the process e{sup +}e{sup -} {yields} e{sup +}{nu}{sub e}W{sup -} where it decays into two hadronic jets. This study focuses of the measurement of W boson mass with and without beamstrahlung and initial state radiation (ISR) effects. The JLC Study Framework (JSF) is employed for this purpose. The center-of-mass energy is set at 500 GeV. (author)

Management of Decommissioning on a Multi-Facility Site

International Nuclear Information System (INIS)

Laraia, Michele; McIntyre, Peter; Visagie, Abrie

2008-01-01

The management of the decommissioning of multi-facility sites may be inadequate or inappropriate if based on approaches and strategies developed for sites consisting of only a single facility. The varied nature of activities undertaken, their interfaces and their interdependencies are likely to complicate the management of decommissioning. These issues can be exacerbated where some facilities are entering the decommissioning phase while others are still operational or even new facilities are being built. Multi-facility sites are not uncommon worldwide but perhaps insufficient attention has been paid to optimizing the overall site decommissioning in the context of the entire life cycle of facilities. Decommissioning management arrangements need to be established taking a view across the whole site. A site-wide decommissioning management system is required. This should include a project evaluation and approval process and specific arrangements to manage identified interfaces and interdependencies. A group should be created to manage decommissioning across the site, ensuring adequate and consistent practices in accordance with the management system. Decommissioning management should be aimed at the entire life cycle of facilities. In the case of multi facility sites, the process becomes more complex and decommissioning management arrangements need to be established with a view to the whole site. A site decommissioning management system, a group that is responsible for decommissioning on site, a site project evaluation and approval process and specific arrangements to manage the identified interfaces are key areas of a site decommissioning management structure that need to be addressed to ensure adequate and consistent decommissioning practices. A decommissioning strategy based on single facilities in a sequential manner is deemed inadequate

Lattice diffusion of a single molecule in solution

Science.gov (United States)

Ruggeri, Francesca; Krishnan, Madhavi

2017-12-01

The ability to trap a single molecule in an electrostatic potential well in solution has opened up new possibilities for the use of molecular electrical charge to study macromolecular conformation and dynamics at the level of the single entity. Here we study the diffusion of a single macromolecule in a two-dimensional lattice of electrostatic traps in solution. We report the ability to measure both the size and effective electrical charge of a macromolecule by observing single-molecule transport trajectories, typically a few seconds in length, using fluorescence microscopy. While, as shown previously, the time spent by the molecule in a trap is a strong function of its effective charge, we demonstrate here that the average travel time between traps in the landscape yields its hydrodynamic radius. Tailoring the pitch of the lattice thus yields two different experimentally measurable time scales that together uniquely determine both the size and charge of the molecule. Since no information is required on the location of the molecule between consecutive departure and arrival events at lattice sites, the technique is ideally suited to measurements on weakly emitting entities such as single molecules.

Reactive sites influence in PMMA oligomers reactivity: a DFT study

Science.gov (United States)

Paz, C. V.; Vásquez, S. R.; Flores, N.; García, L.; Rico, J. L.

2018-01-01

In this work, we present a theoretical study of methyl methacrylate (MMA) living anionic polymerization. The study was addressed to understanding two important experimental observations made for Michael Szwarc in 1956. The unexpected effect of reactive sites concentration in the propagation rate, and the self-killer behavior of MMA (deactivating of living anionic polymerization). The theoretical calculations were performed by density functional theory (DFT) to obtain the frontier molecular orbitals values. These values were used to calculate and analyze the chemical interaction descriptors in DFT-Koopmans’ theorem. As a result, it was observed that the longest chain-length species (related with low concentration of reactive sites) exhibit the highest reactivity (behavior associated with the increase of the propagation rate). The improvement in this reactivity was attributed to the crosslinking produced in the polymethyl methacrylate chains. Meanwhile, the self-killer behavior was associated with the intermolecular forces present in the reactive sites. This behavior was associated to an obstruction in solvation, since the active sites remained active through all propagation species. The theoretical results were in good agreement with the Szwarc experiments.

The effect of simulation courseware on critical thinking in undergraduate nursing students: multi-site pre-post study.

Science.gov (United States)

Shin, Hyunsook; Ma, Hyunhee; Park, Jiyoung; Ji, Eun Sun; Kim, Dong Hee

2015-04-01

The use of simulations has been considered as opportunities for students to enhance their critical thinking (CT), but previous studies were limited because they did not provide in-depth information on the working dynamics of simulation or on the effects of the number of simulation exposures on CT. This study examined the effect of an integrated pediatric nursing simulation used in a nursing practicum on students' CT abilities and identified the effects of differing numbers of simulation exposures on CT in a multi-site environment. The study used a multi-site, pre-test, post-test design. A total of 237 nursing students at three universities enrolled in a pediatric practicum participated in this study from February to December 2013. All three schools used the same simulation courseware, including the same simulation scenarios, evaluation tools, and simulation equipment. The courseware incorporated high-fidelity simulators and standardized patients. Students at school A completed one simulation session, whereas students at schools B and C completed two and three simulation sessions, respectively. Yoon's Critical Thinking Disposition tool (2008) was used to measure students' CT abilities. The gains in students' CT scores varied according to their numbers of exposures to the simulation courseware. With a single exposure, there were no statistically significant gains in CT, whereas three exposures to the courseware produced significant gains in CT. In seven subcategories of critical thinking, three exposures to the simulation courseware produced CT gains in the prudence and intellectual eagerness subcategories, and the overall simulation experience produced CT gains in the prudence, systematicity, healthy skepticism, and intellectual eagerness subcategories. Simulation courseware may produce positive learning outcomes for prudence in nursing education. In addition, the findings from the multi-site comparative study may contribute to greater understanding of how patient

Single-Station Sigma for the Iranian Strong Motion Stations

Science.gov (United States)

Zafarani, H.; Soghrat, M. R.

2017-11-01

In development of ground motion prediction equations (GMPEs), the residuals are assumed to have a log-normal distribution with a zero mean and a standard deviation, designated as sigma. Sigma has significant effect on evaluation of seismic hazard for designing important infrastructures such as nuclear power plants and dams. Both aleatory and epistemic uncertainties are involved in the sigma parameter. However, ground-motion observations over long time periods are not available at specific sites and the GMPEs have been derived using observed data from multiple sites for a small number of well-recorded earthquakes. Therefore, sigma is dominantly related to the statistics of the spatial variability of ground motion instead of temporal variability at a single point (ergodic assumption). The main purpose of this study is to reduce the variability of the residuals so as to handle it as epistemic uncertainty. In this regard, it is tried to partially apply the non-ergodic assumption by removing repeatable site effects from total variability of six GMPEs driven from the local, Europe-Middle East and worldwide data. For this purpose, we used 1837 acceleration time histories from 374 shallow earthquakes with moment magnitudes ranging from M w 4.0 to 7.3 recorded at 370 stations with at least two recordings per station. According to estimated single-station sigma for the Iranian strong motion stations, the ratio of event-corrected single-station standard deviation ( Φ ss) to within-event standard deviation ( Φ) is about 0.75. In other words, removing the ergodic assumption on site response resulted in 25% reduction of the within-event standard deviation that reduced the total standard deviation by about 15%.

Single-Sex Classrooms and Reading Achievement: An Exploratory Study

Science.gov (United States)

Stotsky, Sandra; Denny, George

2012-01-01

Gendered schooling is growing in the United States, but little research exists on single-sex classes in public elementary schools. This study sought to find out if single-sex classes in two elementary schools made a difference in boys' reading gains in 2008-2009, as judged by scores on the state's annual literacy test. In one school, boys in the…

Single-ion irradiation: physics, technology and applications

International Nuclear Information System (INIS)

Ohdomari, Iwao

2008-01-01

Among the various radiation effects which involve the study of radiation environments, responses of materials and devices to radiation, radiation testing and radiation hardening of devices and equipment, this review mainly considers the radiation effects induced by alpha particles and other ions used in semiconductor technology on Si crystals and Si devices. We first describe the single-ion microprobe that enables the study of the site dependence of radiation hardness in a semiconductor device. Next, we describe single-ion implantation as a tool for suppressing fluctuation in device function induced by the discrete number and random position of dopant atoms. Finally, we describe the common features associated with both 'probing' and 'modification' in terms of the nature and behaviour of defect clusters induced by single-ion irradiation. A special feature of the review is that the radiation effects discussed here are induced by 'single' particles, and not by particle beams. Although there is a great amount of accumulated data on radiation effects, they are discussed in the conventional terms of 'dose' or 'fluence,' whose unit is cm -2 . Therefore, this review provides complementary information on radiation effects. (topical review)

Wildlife studies on the Hanford site: 1994 Highlights report

Energy Technology Data Exchange (ETDEWEB)

Cadwell, L.L. [ed.

1995-04-01

The purposes of the project are to monitor and report trends in wildlife populations; conduct surveys to identify, record, and map populations of threatened, endangered, and sensitive plant and animal species; and cooperate with Washington State and federal and private agencies to help ensure the protection afforded by law to native species and their habitats. Census data and results of surveys and special study topics are shared freely among cooperating agencies. Special studies are also conducted as needed to provide additional information that may be required to assess, protect, or manage wildlife resources at Hanford. This report describes highlights of wildlife studies on the Site in 1994. Redd counts of fall chinook salmon in the Hanford Reach suggest that harvest restrictions directed at protecting Snake River salmon may have helped Columbia River stocks as well. The 1994 count (5619) was nearly double that of 1993 and about 63% of the 1989 high of approximately 9000. A habitat map showing major vegetation and land use cover types for the Hanford Site was completed in 1993. During 1994, stochastic simulation was used to estimate shrub characteristics (height, density, and canopy cover) across the previously mapped Hanford landscape. The information provided will be available for use in determining habitat quality for sensitive wildlife species. Mapping Site locations of plant species of concern continued during 1994. Additional sensitive plant species data from surveys conducted by TNC were archived. The 10 nesting pairs of ferruginous hawks that used the Hanford Site in 1993 represented approximately 25% of the Washington State population.

Wildlife studies on the Hanford site: 1994 Highlights report

International Nuclear Information System (INIS)

Cadwell, L.L.

1995-04-01

The purposes of the project are to monitor and report trends in wildlife populations; conduct surveys to identify, record, and map populations of threatened, endangered, and sensitive plant and animal species; and cooperate with Washington State and federal and private agencies to help ensure the protection afforded by law to native species and their habitats. Census data and results of surveys and special study topics are shared freely among cooperating agencies. Special studies are also conducted as needed to provide additional information that may be required to assess, protect, or manage wildlife resources at Hanford. This report describes highlights of wildlife studies on the Site in 1994. Redd counts of fall chinook salmon in the Hanford Reach suggest that harvest restrictions directed at protecting Snake River salmon may have helped Columbia River stocks as well. The 1994 count (5619) was nearly double that of 1993 and about 63% of the 1989 high of approximately 9000. A habitat map showing major vegetation and land use cover types for the Hanford Site was completed in 1993. During 1994, stochastic simulation was used to estimate shrub characteristics (height, density, and canopy cover) across the previously mapped Hanford landscape. The information provided will be available for use in determining habitat quality for sensitive wildlife species. Mapping Site locations of plant species of concern continued during 1994. Additional sensitive plant species data from surveys conducted by TNC were archived. The 10 nesting pairs of ferruginous hawks that used the Hanford Site in 1993 represented approximately 25% of the Washington State population

KAJIAN ZONASI PENGEMBANGAN KAWASAN PUSAKA. STUDI KASUS: SITUS SANGIRAN, SRAGEN (Zoning Study of Heritage Site Development Case Study: Sangiran Site, Sragen

Directory of Open Access Journals (Sweden)

Wiendu Nuryanti

2008-11-01

Full Text Available ABSTRAK Sebagai Warisan Budaya Dunia (World Culture Heritage yang ditetapkan oleh UNESCO pada tanggal 5 Desember 1996, Situs Sangiran merupakan bagian penting dalam sejarah manusia di dunia. Sesuai dengan keputusan Menteri Pendidikan dan Kebudayaan (Nomor 0701011977, situs tersebut telah ditetapkan sebagai cagar budaya (Widianto, et al.,1996. Penelitian ini memiliki dua tujuan utama: (1 menyusun konsepsi dasar pelestarian, dan (2 menyusun arahan desain (guidelines pelestarian Situs Sangiran. Permasalahan utama dari kajian ini adalah perubahan lahan karena faktor alam dan aktivitas manusia (pertanian, pembangunan, penambangan, ancaman pencurian, penggelapan, dan jual beli fosil, rendahnya partisipasi masyarakat dalam upaya pelestarian Situs Sangiran, dan belum adanya panduan/arahan pelestarian dan pemanfaatan wisata yang jelas. Dengan metoda kualitatif naturalistik, dihasilkan konsepsi (prinsip dasar pelestarian Situs Sangiran Sragen, dalanr masing-masing zona (zona I -3 sesuai dengan potensi tiap zona yang perlu dilestarikan dan dikernbangkan. Analisis yang digunakan dalam hal ini adalah analisis makro, meso, dan mikro. Dari kajian ini dapat disimpulkan bahwa dalam merencanakan pelestarian Situs Sangiran, hal terpenting adalah mentaati zonasi dasar situs, di mana setiap zona akan merniliki guidelines  tersendiri. Guidelines terdiri atas pengembangan produk (Klaster Ngebung, Bukuran, Dayu, street furniture, serta pemberdayaan masyarakat.   ABSTRACT  UNESCO has established Sangiran Site as a World Culture Heritage in December 5th 1996. Its present is important to the history of mankind in the world. Widianto, et al., 1996, stated that Sangiran site has become a Cultural Site regarding to the declaration of Minister of Culture and Education (No. 070/0/1977. This Research has two main purposes, (1 to arrange a conception of basic preservation, and (2 to arrange a design guidelines of Sangiran Site Preservation. There are several major issues in

76 FR 81959 - Notice of Proposed Information Collection: Comment Request; Homelessness Prevention Study Site...

Science.gov (United States)

2011-12-29

... Information Collection: Comment Request; Homelessness Prevention Study Site Visits AGENCY: Office of the Chief.... This Notice also lists the following information: Title of Proposal: Homelessness Prevention Study Site... of the Paperwork Reduction Act requirements associated with HUD's Homelessness Prevention Study Site...

Immediate Loading of Single Implants in the Anterior Maxilla: A 1-Year Prospective Clinical Study on 34 Patients

Directory of Open Access Journals (Sweden)

Miguel Stanley

2017-01-01

Full Text Available Purpose. To present the outcomes of immediately loaded single implants placed in the anterior maxilla. Methods. Over a 2-year period, all patients referred to a private clinic were considered for enrolment in this study. Inclusion criteria were single-tooth placement in postextraction sockets or healed sites of the anterior maxilla. All implants were immediately loaded and followed for a period of 1 year after the placement of definitive crowns. The outcome measures were implant stability, survival, and success. Results. 34 patients were selected and 43 tapered implants with a knife-edge thread design and a nanostructured, calcium-incorporated surface (Anyridge®, Megagen, Gyeongsang, Korea were installed. Two implants were not sufficiently stable at placement (ISQ < 60 and were considered failed for immediate loading; 41 implants had an ISQ ≥ 60 at placement and were immediately loaded. One year after the placement of definitive crowns, no implant failures were reported, for a survival rate of 100%. No biological complications were found, but 2 implants had their prosthetic abutments loosened: the implant success rate was 95.2%. Conclusions. In the present study on the immediate loading of single implants in the anterior maxilla, positive outcomes were reported, with high survival (100% and success (95.2% rates (the present study has been registered in the ISRCTN registry, a publicly available trial register recognized by WHO and ICMJE, with number ISRCTN12935478.

Evaluation of the Cortical Bone Reaction Around of Implants Using a Single-Use Final Drill: A Histologic Study.

Science.gov (United States)

Gehrke, Sergio Alexandre

2015-07-01

This study was designed to compare the cortical bone reaction following traditional osteotomy or the use of a single-use final drill in the osseointegration of implants in the tibia of rabbits. For this study, 48 conical implants, of standard surface type and design and manufactured by the same company, were inserted into the tibiae of 12 rabbits and removed after 30 or 60 days for histologic analysis. Two test groups were prepared according to the drill sequence used for the osteotomy at the preparation sites: in the control group was used a conventional drill sequence with several uses, whereas the test group (tesG) used a single-use final drill. The bone-to-implant contact and qualitative factors of the resulting cortical bone were assessed. Both techniques produced good implant integration. Differences in the linear bone-to-implant contact were observed between the drilling procedures as time elapsed in vivo, with the tesG appearing to have clinical advantages. Both groups exhibited new bone in quantity and in quality; however, the tesG exhibited a higher level of new bone deposition than the control group. Within the limitations of this study, the findings suggest that the use of a single-use final drill leads to better and faster organization of the cortical bone area during the evaluated period and may avoid the possible problems that can be caused by worn drills.

Electrocatalytic Water Oxidation by a Homogeneous Copper Catalyst Disfavors Single-Site Mechanisms.

Science.gov (United States)

Koepke, Sara J; Light, Kenneth M; VanNatta, Peter E; Wiley, Keaton M; Kieber-Emmons, Matthew T

2017-06-28

Deployment of solar fuels derived from water requires robust oxygen-evolving catalysts made from earth abundant materials. Copper has recently received much attention in this regard. Mechanistic parallels between Cu and single-site Ru/Ir/Mn water oxidation catalysts, including intermediacy of terminal Cu oxo/oxyl species, are prevalent in the literature; however, intermediacy of late transition metal oxo species would be remarkable given the high d-electron count would fill antibonding orbitals, making these species high in energy. This may suggest alternate pathways are at work in copper-based water oxidation. This report characterizes a dinuclear copper water oxidation catalyst, {[(L)Cu(II)] 2 -(μ-OH) 2 }(OTf) 2 (L = Me 2 TMPA = bis((6-methyl-2-pyridyl)methyl)(2-pyridylmethyl)amine) in which water oxidation proceeds with high Faradaic efficiency (>90%) and moderate rates (33 s -1 at ∼1 V overpotential, pH 12.5). A large kinetic isotope effect (k H /k D = 20) suggests proton coupled electron transfer in the initial oxidation as the rate-determining step. This species partially dissociates in aqueous solution at pH 12.5 to generate a mononuclear {[(L)Cu(II)(OH)]} + adduct (K eq = 0.0041). Calculations that reproduce the experimental findings reveal that oxidation of either the mononuclear or dinuclear species results in a common dinuclear intermediate, {[LCu(III)] 2 -(μ-O) 2 } 2+ , which avoids formation of terminal Cu(IV)═O/Cu(III)-O • intermediates. Calculations further reveal that both intermolecular water nucleophilic attack and redox isomerization of {[LCu(III)] 2 -(μ-O) 2 } 2+ are energetically accessible pathways for O-O bond formation. The consequences of these findings are discussed in relation to differences in water oxidation pathways between Cu catalysts and catalysts based on Ru, Ir, and Mn.

A Study of Social Networking Sites for Learners of Japanese

Directory of Open Access Journals (Sweden)

Fusako Ota

2011-01-01

Full Text Available Social Networking Sites (SNSs such as “Facebook” and “MySpace” have been used by many people from different countries around the world, and they have recently been applied to second language (L2 learning, both inside and outside classrooms. A number of researchers have investigated the utility of SNSs, and some language researchers have studied the use of SNSs for L2 learning in language classrooms. However, the study of the usage of SNSs for L2 learning outside the classroom has not yet been studied thoroughly, despite the fact that many communities and groups exist for users who are interested in learning L2 on such sites. This article examines the nature and extent of SNS communities available specifically for L2 learners of Japanese, and describes the usage which is being made of these communities in particular on the SNSs, “mixi” and “Facebook”. Furthermore, the beneficial aspects of using such sites for L2 learning will be discussed.

A New Theoretical Approach to Single-Molecule Fluorescence Optical Studies of RNA Dynamics

International Nuclear Information System (INIS)

Zhao Xinghai; Shan Guangcun; Bao Shuying

2011-01-01

Single-molecule fluorescence spectroscopy in condensed phases has many important chemical and biological applications. The single-molecule fluorescence measurements contain information about conformational dynamics on a vast range of time scales. Based on the data analysis protocols methodology proposed by X. Sunney Xie, the theoretical study here mainly focuses on the single-molecule studies of single RNA with interconversions among different conformational states, to with a single FRET pair attached. We obtain analytical expressions for fluorescence lifetime correlation functions that relate changes in fluorescence lifetime to the distance-dependent FRET mechanism within the context of the Smoluchowski diffusion model. The present work establishes useful guideline for the single-molecule studies of biomolecules to reveal the complicated folding dynamics of single RNA molecules at nanometer scale.

Site study plan for non-routine laboratory rock mechanics, Deaf Smith County Site, Texas: Revision 1

International Nuclear Information System (INIS)

1987-12-01

This Site Study Plan describes the non-routine rock mechanics and thermal properties laboratory testing program planned for the characterization of site-specific geologic materials for the Deaf Smith County site, Texas. The study design provides for measurements of index, mechanical, thermomechanical, thermal and special properties for the host salt, and where appropriate, for nonhost lithologies. The types of tests which will be conducted are constant stress (creep) tests, constant strain (stress relaxation) tests, constant strain-rate tests, constant stress-rate tests, cyclic loading tests, hollow cylinder tests, uniaxial and triaxial compression tests, direct tension tests, indirect (triaxial) shear tests, thermal property determinations (conductivity, specific heat, expansivity, and diffusivity), fracture healing tests, thermal decrepitation tests, moisture content determinations, and petrographic and micromechanics analyses. Tests will be conducted at confining pressures up to 30 MPa and temperatures up to 300/degree/C. These data are used to construct mathematical models for the phenomenology of salt deformation. The models are then used in finite-element codes to predict repository response. A tentative testing schedule and milestone log are given. The duration of the testing program is expected to be approximately 5 years. 44 refs., 13 figs., 13 tabs

SLAC site design aesthetics

International Nuclear Information System (INIS)

Hall, F.F.

1985-10-01

Stanford Linear Accelerator Center (SLAC) is a single mission laboratory dedicated to basic research in high energy particle physics. SLAC site also houses Stanford Synchrotron Radiation Laboratory (SSRL) which is a multi-mission laboratory for research using beams of ultraviolet light and low energy photons as emitted tangentially from SLAC colliding beam facilities. This paper discusses various aspects of SLAC site design aesthetics under the following headings: (1) imposed footprint of SLAC, (2) description of selected site, (3) use of earth cover for radiation and sight screens, (4) use of landscaping for cosmetic purposes, (5) use of exterior paint colors to soften SLAC impact on neighbors, (6) relocation of SLAC main entrance, (7) relocation of SLAC collider arcs and experimental hall, (8) parking lots and storage yards, and (9) land use zoning at SLAC

An economic study of the site of Marcoule; Etude economique du site de Marcoule

Energy Technology Data Exchange (ETDEWEB)

Duprat, H [Commissariat a l' Energie Atomique, Marcoule (France). Centre d' Etudes Nucleaires

1964-07-01

The study of this site of the Marcoule Center shows that its regional economical influence is limited to the buying power distributed among its personnel. This entails distortions between first this supplementary buying power and the overall markets within the possible Marcoule influence zone, and secondly the concentration on Bagnols-sur-Ceze and this town's normal extension possibilities. (author) [French] L'etude du site de Marcoule demontre que son influence economique se limite, pour la region, au pouvoir d'achat distribue a son personnel. Ceci entraine une disproportion d'une part entre ce pouvoir d'achat supplementaire et l'ensemble des marches contenus dans l'aire d'influence possible de Marcoule, d'autre part entre la concentration realisee a Bagnole-sur-Ceze et la capacite d'extension normale de cette agglomeration. (auteur)

Web Site of King Faysal for Researches and Islamic Studies :Evaluative Case Study . 2

Directory of Open Access Journals (Sweden)

Hind Badi Aly al-Badi

2007-06-01

Full Text Available This study makes evaluation to the website of King Faisal Islamic Study & Research Center (KFISRC in relation to its site, advanced design, services rendered, public users and easy-to-search including its discharged duties; content, form and scope.The study aims to evaluate the website of KFISRC published in the Internet as well as the volume of its sample users, and to determine the motivations of use.The study was conducted on the Second Semester in 1426H. / 2005G. The researcher has relied in the evaluation case study on "on-line access" in the Internet; a matter which was imposed by the nature and objectives of the study and followed by an evaluation-analysis methodology based on the measures derived from Website & Information Resources Measures in the Internet. The information were gathered using the questionnaire forms which were distributed to a random sample of 15% of the society slide subject of the study totaling 1755 of post-graduate female students; i.e. Master degree; enrolled in Library & Information, Arabic Language and History Departments of Faculty of Arts & Humanities , King Abdulaziz University, Jeddah; and post-graduate female students; i.e. Master degree; enrolled in Faculty of Da'wa & Fundamentals of Religion, Umm Al-Qura University, Makkah Al-Mukarramah, including male and female staff of KFISRC. The study has reached to the number of findings, mainly as follows:The volume of the users has reached to 40.7% of the sampling. One of the reasons of the decreasing percentage in the number of the site users of KFISRC is that 32.4% did not know about the existence of the site in the Internet; whereas, 24.1% of the sampling whose most important motivation to use the site is to know whether the resources searched by them would be available in the data-bases of the KFISRC or not

Web Site of King Faysal for Researches and Islamic Studies :Evaluative Case Study . 1

Directory of Open Access Journals (Sweden)

Hind Badi Aly al-Badi

2007-03-01

Full Text Available This study makes evaluation to the website of King Faisal Islamic Study & Research Center (KFISRC in relation to its site, advanced design, services rendered, public users and easy-to-search including its discharged duties; content, form and scope.The study aims to evaluate the website of KFISRC published in the Internet as well as the volume of its sample users, and to determine the motivations of use.The study was conducted on the Second Semester in 1426H. / 2005G. The researcher has relied in the evaluation case study on "on-line access" in the Internet; a matter which was imposed by the nature and objectives of the study and followed by an evaluation-analysis methodology based on the measures derived from Website & Information Resources Measures in the Internet. The information were gathered using the questionnaire forms which were distributed to a random sample of 15% of the society slide subject of the study totaling 1755 of post-graduate female students; i.e. Master degree; enrolled in Library & Information, Arabic Language and History Departments of Faculty of Arts & Humanities , King Abdulaziz University, Jeddah; and post-graduate female students; i.e. Master degree; enrolled in Faculty of Da'wa & Fundamentals of Religion, Umm Al-Qura University, Makkah Al-Mukarramah, including male and female staff of KFISRC. The study has reached to the number of findings, mainly as follows:The volume of the users has reached to 40.7% of the sampling. One of the reasons of the decreasing percentage in the number of the site users of KFISRC is that 32.4% did not know about the existence of the site in the Internet; whereas, 24.1% of the sampling whose most important motivation to use the site is to know whether the resources searched by them would be available in the data-bases of the KFISRC or not

Feasibility study for the United Heckathorn Superfund Site, Richmond, California

Energy Technology Data Exchange (ETDEWEB)

Lincoff, A.H. [US Environmental Protection Agency, San Francisco, CA (United States). Region IX; Costan, G.P.; Montgomery, M.S.; White, P.J. [Pacific Northwest Lab., Richland, WA (United States)

1994-07-01

The United Heckathom Superfund Site in Richmond, California, was used to formulate pesticides from approximately 1947 to 1966. Soils at the site and sediments in the harbor were contaminated with various chlorinated pesticides, primarily DDT, as a result of these activities. The US Environmental Protection Agency listed the site on the Superfund National Priorities List in 1990. This document is part of the Remedial Investigation and Feasibility Study phase of the Superfund response, which will provide the basis for selection of a final remedy that will protect human health and the environment and achieve compliance with federal and state envirorunental laws.

Feasibility study for the United Heckathorn Superfund Site, Richmond, California

International Nuclear Information System (INIS)

Lincoff, A.H.

1994-07-01

The United Heckathom Superfund Site in Richmond, California, was used to formulate pesticides from approximately 1947 to 1966. Soils at the site and sediments in the harbor were contaminated with various chlorinated pesticides, primarily DDT, as a result of these activities. The US Environmental Protection Agency listed the site on the Superfund National Priorities List in 1990. This document is part of the Remedial Investigation and Feasibility Study phase of the Superfund response, which will provide the basis for selection of a final remedy that will protect human health and the environment and achieve compliance with federal and state envirorunental laws

/sup 1/H nuclear magnetic resonance studies of the conformation of an ATP analogue at the active site of Na,K-ATPase from kidney medulla

Energy Technology Data Exchange (ETDEWEB)

MacD. Stewart, J.M.; Grisham, C.M.

1988-06-28

/sup 1/H nuclear magnetic relaxation measurements have been used to determine the three-dimensional conformation of an ATP analogue, Co(NH/sub 3/)/sub 4/ATP, at the active site of sheep kidney Na,K-ATPase. Previous studies have shown that Co(NH/sub 4/)/sub 4/ATP is a competitive inhibitor with respect to MnATP for the Na,K-ATPase and that Mn/sup 2 +/ bound to a single, high-affinity site on the ATPase can be an effective paramagnetic probe for nuclear relaxation studies of the Na-K-ATPase. From the paramagnetic effect of Mn/sup 2 +/ bound to the APTase on the longitudinal relaxation rates of the protons of Co(NH/sub 3/)/sub 4/ATP at the substrate site (at 300 and 361 MHz), Mn-H distances to seven protons on the bound nucleotide were determined. Taken together with previous /sup 31/P nuclear relaxation data, these measurements are consistent with a single nucleotide conformation at the active site. The nucleotide adopts a bent configuration, in which the triphosphate chain lies nearly parallel to the adenine moiety. The glycosidic torsion angle is 35/sup 0/, and the conformation of the ribose ring is slightly N-type. The bound Mn/sup 2 +/ lies above and in the plane of the adenine ring. The distances from Mn/sup 2 +/ to N/sub 6/ and N/sub 7/ are too large for first coordination sphere complexes but are appropriate for second-sphere complexes involving, for example, intervening hydrogen-bonded water molecules. The NMR data also indicate that the structure of the bound ATP analogue is independent of the conformational state of the enzyme.

Mesoporous Zeolite Single Crystals for Catalytic Hydrocarbon Conversion

DEFF Research Database (Denmark)

Schmidt, I.; Christensen, Claus H.; Kustova, Marina

2005-01-01

Recently, mesoporous zeolite single crystals were discovered. They constitute a novel family of materials that features a combined micropore and mesopore architecture within each individual crystal. Here, we briefly summarize recent catalytic results from cracking and isomerization of alkalies......, alkylation of aromatics and present new results on isomerization of aromatics. Specifically, the shape-selective isomerization of meta-xylenc into para-xylene and ortho-xylene is studied. In all these reactions, rnesoporous zeolite single crystals prove to be unique catalysts since they provide easy...... transport to and from active sites and at the same time maintain the shape-selectivity required. Thus, all these results support the idea that the beneficial effect of the mesopores system in the mesoporous zeolite single crystals call be solely attributed to enhanced mass transport....

Opioid binding site in EL-4 thymoma cell line

International Nuclear Information System (INIS)

Fiorica, E.; Spector, S.

1988-01-01

Using EL-4 thymoma cell-line we found a binding site similar to the k opioid receptor of the nervous system. The Scatchard analysis of the binding of [ 3 H] bremazocine indicated a single site with a K/sub D/ = 60 +/- 17 nM and Bmax = 2.7 +/- 0.8 pmols/10 6 cells. To characterize this binding site, competition studies were performed using selective compounds for the various opioid receptors. The k agonist U-50,488H was the most potent displacer of [ 3 H] bremazocine with an IC 50 value = 0.57μM. The two steroisomers levorphanol and dextrorphan showed the same affinity for this site. While morphine, [D-Pen 2 , D-Pen 5 ] enkephalin and β-endorphin failed to displace, except at very high concentrations, codeine demonstrated a IC 50 = 60μM, that was similar to naloxone. 32 references, 3 figures, 2 tables

Haplotype inference in general pedigrees with two sites

Directory of Open Access Journals (Sweden)

Doan Duong D

2011-04-01

Full Text Available Abstract Background Genetic disease studies investigate relationships between changes in chromosomes and genetic diseases. Single haplotypes provide useful information for these studies but extracting single haplotypes directly by biochemical methods is expensive. A computational method to infer haplotypes from genotype data is therefore important. We investigate the problem of computing the minimum number of recombination events for general pedigrees with two sites for all members. Results We show that this NP-hard problem can be parametrically reduced to the Bipartization by Edge Removal problem and therefore can be solved by an O(2k · n2 exact algorithm, where n is the number of members and k is the number of recombination events. Conclusions Our work can therefore be useful for genetic disease studies to track down how changes in haplotypes such as recombinations relate to genetic disease.

AFM studies on heavy ion irradiated YBCO single crystals

International Nuclear Information System (INIS)

Lakhani, Archana; Marhas, M.K.; Saravanan, P.; Ganesan, V.; Srinivasan, R.; Kanjilal, D.; Mehta, G.K.; Elizabeth, Suja; Bhat, H.L.

2000-01-01

Atomic Force Microscopy (AFM) is extensively used to characterise the surface morphology of high energy ion irradiated single crystals of high temperature superconductor - YBCO. Our earlier systematic studies on thin films of YBCO under high energy and heavy ion irradiation shows clear evidence of ion induced sputtering or erosion, even though the effect is more on the grain boundaries. These earlier results were supported by electrical resistance measurements. In order to understand more clearly, the nature of surface modification at these high energies, AFM studies were carried out on single crystals of YBCO. Single crystals were chosen in order to see the effect on crystallites alone without interference from grain boundaries. 200 MeV gold ions were used for investigation using the facilities available at Nuclear Science Centre, New Delhi. The type of ion and the range of energies were chosen to meet the threshold for electronically mediated defect production. The results are in conformity with our earlier studies and will be described in detail in the context of electronic energy loss mediated sputtering or erosion. (author)

Geophysical study of the Peinan Archaeological Site, Taiwan

Science.gov (United States)

Tong, Lun-Tao; Lee, Kun-Hsiu; Yeh, Chang-Keng; Hwang, Yan-Tsong; Chien, Jeng-Ming

2013-02-01

The Peinan archaeological site is the most intact Neolithic village with slate coffin burial complexes in Taiwan. However, the area that potentially contains significant ancient remains is covered by dense vegetation. No reliable data show the distribution of the ancient village, and no geophysical investigation has been performed at this site. To evaluate various geophysical methods under the geological setting and surface condition of the site, the physical properties of the remains were measured and four geophysical methods involving magnetic, electromagnetic (EM), electrical resistivity tomography (ERT), and ground-penetrating radar (GPR) were tested along three parallel profiles. The results imply that the EM and magnetic methods are much cost-effective and suitable for investigating the entire area. GPR and ERT methods can provide high resolution subsurface image, which are much suitable for subsequently detail investigation. The EM and magnetic surveys were thus conducted over the entire Peinan Cultural Park to understand the distribution of the ancient building remains at the Peinan site. The results of this study were verified by subsequent excavations, which indicate that the EM survey was successful in delineating the majority of the ancient village because the basements of building are highly resistive in comparison to the background sediment. The results of this investigation suggest that the ancient village was broadly distributed over the eastern part of the Peinan Culture Park and extended to the southeast.

Statistical application of groundwater monitoring data at the Hanford Site

International Nuclear Information System (INIS)

Chou, C.J.; Johnson, V.G.; Hodges, F.N.

1993-09-01

Effective use of groundwater monitoring data requires both statistical and geohydrologic interpretations. At the Hanford Site in south-central Washington state such interpretations are used for (1) detection monitoring, assessment monitoring, and/or corrective action at Resource Conservation and Recovery Act sites; (2) compliance testing for operational groundwater surveillance; (3) impact assessments at active liquid-waste disposal sites; and (4) cleanup decisions at Comprehensive Environmental Response Compensation and Liability Act sites. Statistical tests such as the Kolmogorov-Smirnov two-sample test are used to test the hypothesis that chemical concentrations from spatially distinct subsets or populations are identical within the uppermost unconfined aquifer. Experience at the Hanford Site in applying groundwater background data indicates that background must be considered as a statistical distribution of concentrations, rather than a single value or threshold. The use of a single numerical value as a background-based standard ignores important information and may result in excessive or unnecessary remediation. Appropriate statistical evaluation techniques include Wilcoxon rank sum test, Quantile test, ''hot spot'' comparisons, and Kolmogorov-Smirnov types of tests. Application of such tests is illustrated with several case studies derived from Hanford groundwater monitoring programs. To avoid possible misuse of such data, an understanding of the limitations is needed. In addition to statistical test procedures, geochemical, and hydrologic considerations are integral parts of the decision process. For this purpose a phased approach is recommended that proceeds from simple to the more complex, and from an overview to detailed analysis

Probing Single Pt Atoms in Complex Intermetallic Al13Fe4.

Science.gov (United States)

Yamada, Tsunetomo; Kojima, Takayuki; Abe, Eiji; Kameoka, Satoshi; Murakami, Yumi; Gille, Peter; Tsai, An Pang

2018-03-21

The atomic structure of a 0.2 atom % Pt-doped complex metallic alloy, monoclinic Al 13 Fe 4 , was investigated using a single crystal prepared by the Czochralski method. High-angle annular dark-field scanning transmission electron microscopy showed that the Pt atoms were dispersed as single atoms and substituted at Fe sites in Al 13 Fe 4 . Single-crystal X-ray structural analysis revealed that the Pt atoms preferentially substitute at Fe(1). Unlike those that have been reported, Pt single atoms in the surface layers showed lower activity and selectivity than those of Al 2 Pt and bulk Pt for propyne hydrogenation, indicating that the active state of a given single-atom Pt site is strongly dominated by the bonding to surrounding Al atoms.

Optimizing CT angiography in patients with Fontan physiology: single-center experience of dual-site power injection

International Nuclear Information System (INIS)

Sandler, K.L.; Markham, L.W.; Mah, M.L.; Byrum, E.P.; Williams, J.R.

2014-01-01

Aim: To identify adult patients with single-ventricle congenital heart disease and Fontan procedure palliation who have been misdiagnosed with or incompletely evaluated for pulmonary embolism. Additionally, this study was designed to demonstrate that simultaneous, dual-injection of contrast medium into an upper and lower extremity vein is superior to single-injection protocols for CT angiography (CTA) of the chest in this population. Materials and methods: Patients included in the study were retrospectively selected from the Adult Congenital Heart Disease (ACHD) database. Search criteria included history of Fontan palliation and available chest CT examination. Patients were evaluated for (1) type of congenital heart disease and prior operations;(2) indication for initial CT evaluation;(3) route of contrast medium administration for the initial CT examination and resulting diagnosis;(4) whether or not anticoagulation therapy was initiated; and (5) final diagnosis and treatment plan. Results: The query of the ACHD database resulted in 28 individuals or patients with Fontan palliation (superior and inferior venae cavae anastomosed to the pulmonary arteries). Of these, 19 patients with Fontan physiology underwent CTA of the pulmonary circulation, and 17 had suboptimal imaging studies. Unfortunately, seven of these 17 patients (41%) were started on anticoagulation therapy due to a diagnosis of pulmonary embolism that was later excluded. Conclusion: Patients with single-ventricle/Fontan physiology are at risk of thromboembolic disease. Therefore, studies evaluating their complex anatomy must be performed with the optimal imaging protocol to ensure diagnostic accuracy, which is best achieved with dual-injection of an upper and lower extremity central vein. - Highlights: • The adult congenital heart disease population is growing. • Many of these patients have single ventricle/Fontan physiology. • Patients with Fontan physiology are at increased risk for

[Study on Tritium Content in Soil at Sites of Nuclear Explosions on the Territory of Semipalatinsk Test Site].

Science.gov (United States)

Timonova, L V; Lyakhova, O N; Lukashenko, S N; Aidarkhanov, A O

2015-01-01

As a result of investigations carried out on the territory of Semipalatinsk Test Site, tritium was found in different environmental objects--surface and ground waters, vegetation, air environment, and snow cover. The analysis of the data obtained has shown that contamination of environmental objects at the Semipalatinsk Test Site with tritium is associated with the places where underground nuclear tests were performed. Since tritium can originate from an activation reaction and be trapped by pock particles during a test, it was decided to examine the soil in the sites where surface and excavation tests took place. It was found that the concentration of tritium in soil correlates with the concentration of europium. Probably, the concentration of tritium in the soil depends on the character and yield of the tests performed. Findings of the study have revealed that tritium can be found in soil in significant amounts not only in sites where underground nuclear tests took place but also in sites where surface and excavation nuclear tests were carried out.

Effective stochastic generator with site-dependent interactions

Science.gov (United States)

Khamehchi, Masoumeh; Jafarpour, Farhad H.

2017-11-01

It is known that the stochastic generators of effective processes associated with the unconditioned dynamics of rare events might consist of non-local interactions; however, it can be shown that there are special cases for which these generators can include local interactions. In this paper, we investigate this possibility by considering systems of classical particles moving on a one-dimensional lattice with open boundaries. The particles might have hard-core interactions similar to the particles in an exclusion process, or there can be many arbitrary particles at a single site in a zero-range process. Assuming that the interactions in the original process are local and site-independent, we will show that under certain constraints on the microscopic reaction rules, the stochastic generator of an unconditioned process can be local but site-dependent. As two examples, the asymmetric zero-temperature Glauber model and the A-model with diffusion are presented and studied under the above-mentioned constraints.

Raman study of supported molybdenum disulfide single layers

Science.gov (United States)

Durrer, William; Manciu, Felicia; Afanasiev, Pavel; Berhault, Gilles; Chianelli, Russell

2008-10-01

Owing to the increasing demand for clean transportation fuels, highly dispersed single layer transition metal sulfides such as MoS2-based catalysts play an important role in catalytic processes for upgrading and removing sulfur from heavy petroleum feed. In its crystalline bulk form, MoS2 is chemically rather inactive due to a strong tendency to form highly stacked layers, but, when dispersed as single-layer nanoclusters on a support, the MoS2 becomes catalytically active in the hydrogenolysis of sulphur and nitrogen from organic compounds (hydrotreating catalysis). In the present studies alumina-supported MoS2 samples were analyzed by confocal Raman spectroscopy. Evidence of peaks at 152 cm-1, 234 cm-1, and 336 cm-1, normally not seen in the Raman spectrum of the standard bulk crystal, confirms the formation of single layers of MoS2. Furthermore, the presence of the 383 cm-1 Raman line suggests the trigonal prismatic coordination of the formed MoS2 single layers. Depending on the sample preparation method, a restacking of MoS2 layers is also observed, mainly for ex-thiomolybdate samples sulfided at 550 C.

Pharmacokinetics of a new subcutaneous diclofenac formulation administered to three body sites: quadriceps, gluteus, and abdomen.

Science.gov (United States)

Salomone, Salvatore; Piazza, Cateno; Vitale, Daniela Cristina; Cardì, Francesco; Gugliotta, Barbara; Drago, Filippo

2014-02-01

To assess the relative bioavailability of a new subcutaneous (SC) diclofenac hydroxypropyl b-cyclodextrin (HPbCD) formulation administered to three body sites: quadriceps, gluteus, and abdomen. This was a pilot, single-dose, randomized, three-way crossover relative bioavailability study. A total of 12 healthy subjects received a single SC injection of diclofenac HPbCD 50 mg/1 mL in the quadriceps, gluteus, or abdomen. The AUC was comparable after SC diclofenac HPbCD in the quadriceps, gluteus, and abdomen. The Cmax was comparable after SC administration in the quadriceps or abdomen, and ~ 17% higher in the gluteus. The absorption was rapid (30 minutes) after administration of the treatment at any site. The treatment was well tolerated. The relative bioavailability of SC diclofenac HPbCD was comparable when administered to the quadriceps, gluteus, and abdomen. The new diclofenac formulation can therefore be administered subcutaneously to any of these sites without clinically significant differences. A further adequately powered study would be necessary to reveal any differences among injection sites in terms of peak plasma concentration.

Single visit root canal treatment: A prospective study

African Journals Online (AJOL)

2013-08-31

Aug 31, 2013 ... periodontitis were included in the study. ... Conclusion: Single visit RCT is a viable treatment option for teeth having irreversible pulpitis or apical periodontitis ... been previously root treated, required surgical endodontic.

Cell biochemistry studied by single-molecule imaging.

Science.gov (United States)

Mashanov, G I; Nenasheva, T A; Peckham, M; Molloy, J E

2006-11-01

Over the last decade, there have been remarkable developments in live-cell imaging. We can now readily observe individual protein molecules within living cells and this should contribute to a systems level understanding of biological pathways. Direct observation of single fluorophores enables several types of molecular information to be gathered. Temporal and spatial trajectories enable diffusion constants and binding kinetics to be deduced, while analyses of fluorescence lifetime, intensity, polarization or spectra give chemical and conformational information about molecules in their cellular context. By recording the spatial trajectories of pairs of interacting molecules, formation of larger molecular complexes can be studied. In the future, multicolour and multiparameter imaging of single molecules in live cells will be a powerful analytical tool for systems biology. Here, we discuss measurements of single-molecule mobility and residency at the plasma membrane of live cells. Analysis of diffusional paths at the plasma membrane gives information about its physical properties and measurement of temporal trajectories enables rates of binding and dissociation to be derived. Meanwhile, close scrutiny of individual fluorophore trajectories enables ideas about molecular dimerization and oligomerization related to function to be tested directly.

Integrated ground-water monitoring strategy for NRC-licensed facilities and sites: Case study applications

Science.gov (United States)

Price, V.; Temples, T.; Hodges, R.; Dai, Z.; Watkins, D.; Imrich, J.

2007-01-01

This document discusses results of applying the Integrated Ground-Water Monitoring Strategy (the Strategy) to actual waste sites using existing field characterization and monitoring data. The Strategy is a systematic approach to dealing with complex sites. Application of such a systematic approach will reduce uncertainty associated with site analysis, and therefore uncertainty associated with management decisions about a site. The Strategy can be used to guide the development of a ground-water monitoring program or to review an existing one. The sites selected for study fall within a wide range of geologic and climatic settings, waste compositions, and site design characteristics and represent realistic cases that might be encountered by the NRC. No one case study illustrates a comprehensive application of the Strategy using all available site data. Rather, within each case study we focus on certain aspects of the Strategy, to illustrate concepts that can be applied generically to all sites. The test sites selected include:Charleston, South Carolina, Naval Weapons Station,Brookhaven National Laboratory on Long Island, New York,The USGS Amargosa Desert Research Site in Nevada,Rocky Flats in Colorado,C-Area at the Savannah River Site in South Carolina, andThe Hanford 300 Area.A Data Analysis section provides examples of detailed data analysis of monitoring data.

The Cottonwood Lake study area, a long-term wetland ecosystem monitoring site

Science.gov (United States)

Mushet, David M.; Euliss, Ned H.

2012-01-01

The Cottonwood Lake study area is one of only three long-term wetland ecosystem monitoring sites in the prairie pothole region of North America; the other two are Orchid Meadows in South Dakota and St. Denis in Saskatchewan. Of the three, Cottonwood Lake has, by far, the longest continuous data-collection record. Research was initiated at the study area in 1966, and intensive investigations of the hydrology, chemistry, and biology of prairie pothole wetlands continue at the site today. This fact sheet describes the study area, provides an overview of wetland ecology research that has been conducted at the site in the past, and provides an introduction to current work being conducted at the study area by USGS scientists.

Field site selection: getting it right first time around

NARCIS (Netherlands)

Malcolm, Colin A.; El Sayed, Badria; Babiker, Ahmed; Girod, Romain; Fontenille, Didier; Knols, Bart G. J.; Nugud, Abdel Hameed; Benedict, Mark Q.

2009-01-01

The selection of suitable field sites for integrated control of Anopheles mosquitoes using the sterile insect technique (SIT) requires consideration of the full gamut of factors facing most proposed control strategies, but four criteria identify an ideal site: 1) a single malaria vector, 2) an

The Agincourt demographic and health study - site description ...

African Journals Online (AJOL)

The Agincourt demographic and health study - site description, baseline findings and implications. Stephen M Tollman, Kobus Herbst, Michel Garenne, John S.S. Gear, KathJeen Kahn. Abstract. No Abstract. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

Pre-excavation studies of prehistoric cave sites by magnetic prospecting

Science.gov (United States)

Itkis., Sonia; Matskevich, Zinovii; Meshveliani, Tengiz

2014-05-01

Detailed magnetic survey was performed for caves study in Israel (1995-1996) within the framework of the Beit Shemesh Regional Project (Judean Shephelah). The experience accumulated in Israel we applied later (2010) in two Georgian prehistoric cave sites: Cherula and Kotias-Klde. The magnetic method is based on the contrast in magnetic properties between a target object (e.g., buried archaeological feature) and the host medium (i.e, the surrounding bedrock and soil). The feasibility of the magnetic method for cave revealing was evaluated by magnetic susceptibility (κ) measurements of surrounding soil and rocks, and archaeological features: stones making up the walls, ceramic fragments and cave fill. According to data obtained, the κ of soil within caves (cave fill) is higher than that of surrounding soil. The enhancement of cave fill κ occurs because processes associated with human habitation: repeated heating and accumulation of organic debris. Both these processes provide good conditions for the conversion of the iron oxide found within the soil to a strongly ferromagnetic form (Mullins, 1977; Maher, 1986; Dalan and Banerjee, 1998, Itkis and Eppelbaum, 1999; Itkis, 2003) The presence of highly magnetic ceramics in caves also enhances magnetic contrast between practically non-magnetic bed rock (chalk in Ramat Beit Shemesh Site (Israel) and limestone (Georgian sites) and the cave fill, increasing the potential of the magnetic method to reveal caves (Itkis, 2011). Based on magnetic survey results, an excavation revealed a cave with a large amount of well preserved pottery and finds typical of the Early Bronze Age. Both studied cave sites in Georgia were located in Chiatura region of Imeretia province. Cherula site is a karstic rockshelter with a single chamber, ca 100 sq. m. The site was briefly tested in 1970s'. The area excavated in 2010 went to the depth of 60 cm below the present day surface; the limestone bedrock was not reached. The excavation revealed

Safety aspects of geological studies around nuclear installations sites

International Nuclear Information System (INIS)

Faure, J.

1988-01-01

The experience of geological studies of about forty french nuclear sites allows to set out the objectives, the phases and the geographic extensions of workings to be realized for confirming a site. The data to be collected for the safety analysis are specified; they concern the local and regional geology, the geotechnical characteristics and the essential elements for evaluating the hazards related to the soil liquefaction, the surface fracturing and in some cases the volcanic risks. It is necessary to follow up the geology during the installation construction and life. 8 refs. (F.M.)

Exploring the feasibility of multi-site flow cytometric processing of gut associated lymphoid tissue with centralized data analysis for multi-site clinical trials.

Directory of Open Access Journals (Sweden)

Ian McGowan

Full Text Available The purpose of this study was to determine whether the development of a standardized approach to the collection of intestinal tissue from healthy volunteers, isolation of gut associated lymphoid tissue mucosal mononuclear cells (MMC, and characterization of mucosal T cell phenotypes by flow cytometry was sufficient to minimize differences in the normative ranges of flow parameters generated at two trial sites. Forty healthy male study participants were enrolled in Pittsburgh and Los Angeles. MMC were isolated from rectal biopsies using the same biopsy acquisition and enzymatic digestion protocols. As an additional comparator, peripheral blood mononuclear cells (PBMC were collected from the study participants. For quality control, cryopreserved PBMC from a single donor were supplied to both sites from a central repository (qPBMC. Using a jointly optimized standard operating procedure, cells were isolated from tissue and blood and stained with monoclonal antibodies targeted to T cell phenotypic markers. Site-specific flow data were analyzed by an independent center which analyzed all data from both sites. Ranges for frequencies for overall CD4+ and CD8+ T cells, derived from the qPBMC samples, were equivalent at both UCLA and MWRI. However, there were significant differences across sites for the majority of T cell activation and memory subsets in qPBMC as well as PBMC and MMC. Standardized protocols to collect, stain, and analyze MMC and PBMC, including centralized analysis, can reduce but not exclude variability in reporting flow data within multi-site studies. Based on these data, centralized processing, flow cytometry, and analysis of samples may provide more robust data across multi-site studies. Centralized processing requires either shipping of fresh samples or cryopreservation and the decision to perform centralized versus site processing needs to take into account the drawbacks and restrictions associated with each method.

Exploring the feasibility of multi-site flow cytometric processing of gut associated lymphoid tissue with centralized data analysis for multi-site clinical trials.

Science.gov (United States)

McGowan, Ian; Anton, Peter A; Elliott, Julie; Cranston, Ross D; Duffill, Kathryn; Althouse, Andrew D; Hawkins, Kevin L; De Rosa, Stephen C

2015-01-01

The purpose of this study was to determine whether the development of a standardized approach to the collection of intestinal tissue from healthy volunteers, isolation of gut associated lymphoid tissue mucosal mononuclear cells (MMC), and characterization of mucosal T cell phenotypes by flow cytometry was sufficient to minimize differences in the normative ranges of flow parameters generated at two trial sites. Forty healthy male study participants were enrolled in Pittsburgh and Los Angeles. MMC were isolated from rectal biopsies using the same biopsy acquisition and enzymatic digestion protocols. As an additional comparator, peripheral blood mononuclear cells (PBMC) were collected from the study participants. For quality control, cryopreserved PBMC from a single donor were supplied to both sites from a central repository (qPBMC). Using a jointly optimized standard operating procedure, cells were isolated from tissue and blood and stained with monoclonal antibodies targeted to T cell phenotypic markers. Site-specific flow data were analyzed by an independent center which analyzed all data from both sites. Ranges for frequencies for overall CD4+ and CD8+ T cells, derived from the qPBMC samples, were equivalent at both UCLA and MWRI. However, there were significant differences across sites for the majority of T cell activation and memory subsets in qPBMC as well as PBMC and MMC. Standardized protocols to collect, stain, and analyze MMC and PBMC, including centralized analysis, can reduce but not exclude variability in reporting flow data within multi-site studies. Based on these data, centralized processing, flow cytometry, and analysis of samples may provide more robust data across multi-site studies. Centralized processing requires either shipping of fresh samples or cryopreservation and the decision to perform centralized versus site processing needs to take into account the drawbacks and restrictions associated with each method.

A crystallographic and spectroscopic study of crystal sites in the 'spinel' structure; Etude cristallographique et spectroscopique des sites cristallins dans la structure 'spinelle'

Energy Technology Data Exchange (ETDEWEB)

Drifford, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-06-15

A crystallographic study on magnesium aluminates led to the determination of crystal site average distortion. A spectroscopic study of transition elements doped spinels gave the position of the doping element in tetrahedral (A) or octahedral (B) sites, and the local distortion of the latter. The comparison of average and local parameters points to differences in the behaviour of doping elements and shows the size of (A) sites are independent of the host crystal composition while the average size of (B) sites varies with the composition. (author) [French] Une etude cristallographique des aluminates de magnesium a permis de determiner la deformation moyenne des sites cristallins. Une etude spectroscopique des aluminates de magnesium dopes avec des elements de transition a permis de localiser les dopants entre les sites tetraedriques (A) et octaedriques (B) et d'etudier la deformation locale de ces sites. La comparaison entre les parametres moyens et locaux a caracterise le comportement du dopant et montre que les dimensions des sites (A) sont independantes de la composition de la matrice, alors que les caracteristiques geometriques moyennes des sites (B) varient continument avec la composition. (auteur)

Site Characterization Work Plan for Gnome-Coach Site, New Mexico

Energy Technology Data Exchange (ETDEWEB)

DOE/NV

2001-02-13

Project Gnome was the first nuclear experiment conducted under the U.S. Atomic Energy Commission (AEC), predecessor to the U.S. Department of Energy (DOE), Plowshare Program. Gnome was part of a joint government-industry experiment focused on developing nuclear devices exclusively for peaceful purposes. The intent of the Gnome experiment was to evaluate the effects of a nuclear detonation in a salt medium. Historically, Project Gnome consisted of a single detonation of a nuclear device on December 10, 1961. Since the Gnome detonation, the AEC/DOE has conducted surface restoration, site reconnaissance, and decontamination and decommissioning activities at the site. In addition, annual groundwater sampling is performed under a long-term hydrological monitoring program begun in 1980. Coach, an experiment to be located near the Gnome project, was initially scheduled for 1963. Although construction and rehabilitation were completed for Coach, the experiment was canceled and never executed. Known collectively as Project Gnome-Coach, the site is situated within the Salado Formation approximately 25 miles east of Carlsbad, New Mexico, in Eddy County, and is comprised of nearly 680 acres, of which 60 acres are disturbed from the combined AEC/DOE operations. The scope of this work plan is to document the environmental objectives and the proposed technical site investigation strategies that will be utilized for the site characterization of the project. The subsurface at the Gnome-Coach site has two contaminant sources that are fundamentally different in terms of both their stratigraphic location and release mechanism. The goal of this characterization is to collect data of sufficient quantity and quality to establish current site conditions and to use the data to identify and evaluate if further action is required to protect human health and the environment and achieve permanent closure of the site. The results of these activities will be presented in a subsequent corrective

Test Plan for the Demonstration of Geophysical Techniques for Single-Shell Tank Leak Detection at the Hanford Mock Tank Site: Fiscal Year 2001

Energy Technology Data Exchange (ETDEWEB)

Barnett, D. Brent; Gee, Glendon W.; Sweeney, Mark D.

2001-07-31

As part of the Leak Detection, Monitoring and Mitigation (LDMM) program conducted by CH2M HILL 105-A during FY 2001. These tests are being conducted to assess the applicability of these methods (Electrical Resistance Tomography [ERT], High Resolution Resistivity [HRR], Cross-Borehole Seismography [XBS], Cross-Borehole Radar [XBR], and Cross-Borehole Electromagnetic Induction [CEMI]) to the detection and measurement of Single Shell Tank (SST) leaks into the vadose zone during planned sluicing operations. The testing in FY 2001 will result in the selection of up to two methods for further testing in FY 2002. In parallel with the geophysical tests, a Partitioning Interwell Tracer Test (PITT) study will be conducted simultaneously at the Mock Tank to assess the effectiveness of this technology in detecting and quantifying tank leaks in the vadose zone. Preparatory and background work using Cone Penetrometer methods (CPT) will be conducted at the Mock Tank site and an adjacent test area to derive soil properties for groundtruthing purposes for all methods.

Behavior-based safety on construction sites: a case study.

Science.gov (United States)

Choudhry, Rafiq M

2014-09-01

This work presents the results of a case study and describes an important area within the field of construction safety management, namely behavior-based safety (BBS). This paper adopts and develops a management approach for safety improvements in construction site environments. A rigorous behavioral safety system and its intervention program was implemented and deployed on target construction sites. After taking a few weeks of safety behavior measurements, the project management team implemented the designed intervention and measurements were taken. Goal-setting sessions were arranged on-site with workers' participation to set realistic and attainable targets of performance. Safety performance measurements continued and the levels of performance and the targets were presented on feedback charts. Supervisors were asked to give workers recognition and praise when they acted safely or improved critical behaviors. Observers were requested to have discussions with workers, visit the site, distribute training materials to workers, and provide feedback to crews and display charts. They were required to talk to operatives in the presence of line managers. It was necessary to develop awareness and understanding of what was being measured. In the process, operatives learned how to act safely when conducting site tasks using the designed checklists. Current weekly scores were discussed in the weekly safety meetings and other operational site meetings with emphasis on how to achieve set targets. The reliability of the safety performance measures taken by the company's observers was monitored. A clear increase in safety performance level was achieved across all categories: personal protective equipment; housekeeping; access to heights; plant and equipment, and scaffolding. The research reveals that scores of safety performance at one project improved from 86% (at the end of 3rd week) to 92.9% during the 9th week. The results of intervention demonstrated large decreases in

Test-retest and between-site reliability in a multicenter fMRI study.

Science.gov (United States)

Friedman, Lee; Stern, Hal; Brown, Gregory G; Mathalon, Daniel H; Turner, Jessica; Glover, Gary H; Gollub, Randy L; Lauriello, John; Lim, Kelvin O; Cannon, Tyrone; Greve, Douglas N; Bockholt, Henry Jeremy; Belger, Aysenil; Mueller, Bryon; Doty, Michael J; He, Jianchun; Wells, William; Smyth, Padhraic; Pieper, Steve; Kim, Seyoung; Kubicki, Marek; Vangel, Mark; Potkin, Steven G

2008-08-01

In the present report, estimates of test-retest and between-site reliability of fMRI assessments were produced in the context of a multicenter fMRI reliability study (FBIRN Phase 1, www.nbirn.net). Five subjects were scanned on 10 MRI scanners on two occasions. The fMRI task was a simple block design sensorimotor task. The impulse response functions to the stimulation block were derived using an FIR-deconvolution analysis with FMRISTAT. Six functionally-derived ROIs covering the visual, auditory and motor cortices, created from a prior analysis, were used. Two dependent variables were compared: percent signal change and contrast-to-noise-ratio. Reliability was assessed with intraclass correlation coefficients derived from a variance components analysis. Test-retest reliability was high, but initially, between-site reliability was low, indicating a strong contribution from site and site-by-subject variance. However, a number of factors that can markedly improve between-site reliability were uncovered, including increasing the size of the ROIs, adjusting for smoothness differences, and inclusion of additional runs. By employing multiple steps, between-site reliability for 3T scanners was increased by 123%. Dropping one site at a time and assessing reliability can be a useful method of assessing the sensitivity of the results to particular sites. These findings should provide guidance toothers on the best practices for future multicenter studies.

Positron annihilation spectroscopic study of hydrothermal grown n-type zinc oxide single crystal

Energy Technology Data Exchange (ETDEWEB)

Hui, C.W.; Zhang, Z.D.; Zhou, T.J.; Ling, C.C.; Beling, C.D.; Fung, S. [Department of Physics, The University of Hong Kong, Pokfulam Road, Hong Kong (China); Brauer, G.; Anwand, W.; Skorupa, W. [Institut fuer Ionenstrahlphysik und Materialforschung, Forschungszentrum Rossendorf, Postfach 510119, 01314 Dresden (Germany)

2007-07-01

Positron lifetime and coincidence Doppler broadening spectroscopic (CDBS) measurements were carried out to study the defects in two hydrothermal (HT) grown ZnO single crystal samples (HT1 and HT2) obtained from two companies. Single component model could offer good fittings to the room temperature spectra of HT1 and HT2, with the positron lifetimes equal to 199 ps and 181 ps respectively. These two lifetime components were associated with saturated positron trapping into two V{sub Zn}-related defects with different microstructures. The positron lifetimes of HT1 was found to be temperature independent. For the HT2 sample, the positron lifetime remained unchanged with T>200 K and decreased with decreasing temperature as T<200 K. This could be explained by the presence of an additional positron trap having similar electronic environment to that of the delocalized state and competing in trapping positrons with the 181 ps component at low temperatures. Positron-electron autocorrelation function, which was the fingerprint of the annihilation site, was extracted from the CDBS spectrum. The obtained autocorrelation functions of HT1 and HT2 at room temperature, and HT2 at 50 K had features consistent with the above postulates that the 181 ps and the 199 ps components had distinct microstructures and the low temperature positron trap existed in HT2. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Webs sites of women`s studies universitary centers in spain: selection and evaluation

Directory of Open Access Journals (Sweden)

Isabel de Torres Ramírez

2006-12-01

Full Text Available After a brief introduction about the level of development of Women’s Studies in Spain and a list of their parent university institutions, Women’s Studies Web sites are assessed by measuring their usability. The aim is to improve use and accessibility of existing Web sites and, above all, provide encouragement and a model to follow by future Web sites in this area.

Probing correlated quantum many-body systems at the single-particle level

Energy Technology Data Exchange (ETDEWEB)

Endres, Manuel

2013-02-27

The detection of correlation and response functions plays a crucial role in the experimental characterization of quantum many-body systems. In this thesis, we present novel techniques for the measurement of such functions at the single-particle level. Specifically, we show the single-atom- and single-site-resolved detection of an ultracold quantum gas in an optical lattice. The quantum gas is described by the Bose-Hubbard model, which features a zero temperature phase transition from a superfluid to a Mott-insulating state, a paradigm example of a quantum phase transition. We used the aforementioned detection techniques to study correlation and response properties across the superfluid-Mott-insulator transition. The single-atom sensitivity of our method is achieved by fluorescence detection of individual atoms with a high signal-to-noise ratio. A high-resolution objective collects the fluorescence light and yields in situ 'snapshots' of the quantum gas that allow for a single-site-resolved reconstruction of the atomic distribution. This allowed us to measure two-site and non-local correlation-functions across the superfluid-Mott-insulator transition. Non-local correlation functions are based on the information of an extended region of the system and play an important role for the characterization of low-dimensional quantum phases. While non-local correlation functions were so far only theoretical tools, our results show that they are actually experimentally accessible. Furthermore, we used a new thermometry scheme, based on the counting of individual thermal excitations, to measure the response of the system to lattice modulation. Using this method, we studied the excitation spectrum of the system across the two-dimensional superfluid-Mott-insulator transition. In particular, we detected a 'Higgs' amplitude mode in the strongly-interacting superfluid close to the transition point where the system is described by an effectively Lorentz

Probing correlated quantum many-body systems at the single-particle level

International Nuclear Information System (INIS)

Endres, Manuel

2013-01-01

The detection of correlation and response functions plays a crucial role in the experimental characterization of quantum many-body systems. In this thesis, we present novel techniques for the measurement of such functions at the single-particle level. Specifically, we show the single-atom- and single-site-resolved detection of an ultracold quantum gas in an optical lattice. The quantum gas is described by the Bose-Hubbard model, which features a zero temperature phase transition from a superfluid to a Mott-insulating state, a paradigm example of a quantum phase transition. We used the aforementioned detection techniques to study correlation and response properties across the superfluid-Mott-insulator transition. The single-atom sensitivity of our method is achieved by fluorescence detection of individual atoms with a high signal-to-noise ratio. A high-resolution objective collects the fluorescence light and yields in situ 'snapshots' of the quantum gas that allow for a single-site-resolved reconstruction of the atomic distribution. This allowed us to measure two-site and non-local correlation-functions across the superfluid-Mott-insulator transition. Non-local correlation functions are based on the information of an extended region of the system and play an important role for the characterization of low-dimensional quantum phases. While non-local correlation functions were so far only theoretical tools, our results show that they are actually experimentally accessible. Furthermore, we used a new thermometry scheme, based on the counting of individual thermal excitations, to measure the response of the system to lattice modulation. Using this method, we studied the excitation spectrum of the system across the two-dimensional superfluid-Mott-insulator transition. In particular, we detected a 'Higgs' amplitude mode in the strongly-interacting superfluid close to the transition point where the system is described by an effectively Lorentz-invariant low-energy theory

Combined robotic transanal total mesorectal excision (R-taTME) and single-site plus one-port (R-SSPO) technique for ultra-low rectal surgery-initial experience with a new operation approach.

Science.gov (United States)

Kuo, Li-Jen; Ngu, James Chi-Yong; Tong, Yiu-Shun; Chen, Chia-Che

2017-02-01

Robot-assisted rectal surgery is gaining popularity, and robotic single-site surgery is also being explored clinically. We report our initial experience with robotic transanal total mesorectal excision (R-taTME) and radical proctectomy using the robotic single-site plus one-port (R-SSPO) technique for low rectal surgery. Between July 2015 and March 2016, 15 consecutive patients with ultra-low rectal lesions underwent R-taTME followed by radical proctectomy using the R-SSPO technique by a single surgeon. The clinical and pathological results were retrospectively analyzed. The median operative time was 473 (range, 335-569) min, and the estimated blood loss was 33 (range, 30-50) mL. The median number of lymph nodes harvested was 12 (range, 8-18). The median distal resection margin was 1.4 (range, 0.4-3.5) cm, and all patients had clear circumferential resection margins. We encountered a left ureteric transection intraoperatively in one patient, and another patient required reoperation for postoperative adhesive intestinal obstruction. There was no 30-day mortality. R-taTME followed by radical proctectomy using the R-SSPO technique for patients with low rectal lesions is technically feasible and safe without compromising oncologic outcomes. However, there were considerable limitations and a steep learning curve using current robotic technology.

Single Molecule Sensors to Study Hydrophobic Phenomena

OpenAIRE

Geisler, Michael

2010-01-01

The nature and magnitude of the hydrophobic interaction is crucial for many technical and biological processes. In the current study a molecular probe was developed which consists of a single polymer that is bound onto the tip of an AFM cantilever in order to study these effects on the molecular scale. In the following, equilibrium forces are measured and factors of influence such as temperature, cosolvents and chemical composition are varied. Thereby, the system under investigation is so sma...

Innovations in Site Characterization Case Study: The Role of a Conceptual Site Model for Expedited Site Characterization Using the Triad Approach at the Poudre River Site, Fort Collins, Colorado

Science.gov (United States)

This case study examines how systematic planning, an evolving conceptual site model (CSM), dynamic work strategies, and real time measurement technologies can be used to unravel complex contaminant distribution patterns...

Opioid binding site in EL-4 thymoma cell line

Energy Technology Data Exchange (ETDEWEB)

Fiorica, E.; Spector, S.

1988-01-01

Using EL-4 thymoma cell-line we found a binding site similar to the k opioid receptor of the nervous system. The Scatchard analysis of the binding of (/sup 3/H) bremazocine indicated a single site with a K/sub D/ = 60 +/- 17 nM and Bmax = 2.7 +/- 0.8 pmols/10/sup 6/ cells. To characterize this binding site, competition studies were performed using selective compounds for the various opioid receptors. The k agonist U-50,488H was the most potent displacer of (/sup 3/H) bremazocine with an IC/sub 50/ value = 0.57..mu..M. The two steroisomers levorphanol and dextrorphan showed the same affinity for this site. While morphine, (D-Pen/sup 2/, D-Pen/sup 5/) enkephalin and ..beta..-endorphin failed to displace, except at very high concentrations, codeine demonstrated a IC/sub 50/ = 60..mu..M, that was similar to naloxone. 32 references, 3 figures, 2 tables.

Quantifying the cognitive cost of laparo-endoscopic single-site surgeries: Gaze-based indices.

Science.gov (United States)

Di Stasi, Leandro L; Díaz-Piedra, Carolina; Ruiz-Rabelo, Juan Francisco; Rieiro, Héctor; Sanchez Carrion, Jose M; Catena, Andrés

2017-11-01

Despite the growing interest concerning the laparo-endoscopic single-site surgery (LESS) procedure, LESS presents multiple difficulties and challenges that are likely to increase the surgeon's cognitive cost, in terms of both cognitive load and performance. Nevertheless, there is currently no objective index capable of assessing the surgeon cognitive cost while performing LESS. We assessed if gaze-based indices might offer unique and unbiased measures to quantify LESS complexity and its cognitive cost. We expect that the assessment of surgeon's cognitive cost to improve patient safety by measuring fitness-for-duty and reducing surgeons overload. Using a wearable eye tracker device, we measured gaze entropy and velocity of surgical trainees and attending surgeons during two surgical procedures (LESS vs. multiport laparoscopy surgery [MPS]). None of the participants had previous experience with LESS. They performed two exercises with different complexity levels (Low: Pattern Cut vs. High: Peg Transfer). We also collected performance and subjective data. LESS caused higher cognitive demand than MPS, as indicated by increased gaze entropy in both surgical trainees and attending surgeons (exploration pattern became more random). Furthermore, gaze velocity was higher (exploration pattern became more rapid) for the LESS procedure independently of the surgeon's expertise. Perceived task complexity and laparoscopic accuracy confirmed gaze-based results. Gaze-based indices have great potential as objective and non-intrusive measures to assess surgeons' cognitive cost and fitness-for-duty. Furthermore, gaze-based indices might play a relevant role in defining future guidelines on surgeons' examinations to mark their achievements during the entire training (e.g. analyzing surgical learning curves). Copyright © 2017 Elsevier Ltd. All rights reserved.

Summary of site-characterization studies conducted from 1983 through 1987 at the Waste Isolation Pilot Plant (WIPP) site, southeastern New Mexico

International Nuclear Information System (INIS)

Lappin, A.R.

1988-01-01

The Waste Isolation Pilot Plant (WIPP) is being excavated at a depth of approximately 655 m in bedded halites. Site-characterization activities at the WIPP site began in 1976. Characterization activities since 1983 have had the objective of updating the conceptual model for the geologic and hydrologic behavior of the WIPP site and vicinity. This paper discusses aspects of the general conceptual model significant to both site characterization and performance assessment. The geological and hydrologic behavior of the WIPP site and vicinity is transient, and has been transient since at least deposition of the Permian Salado Formation containing the underground workings of the WIPP facility. The Salado Formation deforms regionally in response to gravity, but is very low in permeability, except within approximately two meters of the WIPP facility. The Culebra Dolomite Member of the Rustler Formation dominates the hydrology at the WIPP site. Hydrologic measurements, geologic studies, major-element and minor-element distributions in Culebra fluids, and the results of isotopic studies (stable-isotope, radiocarbon, uranium-disequilibrium, and 87 Sr/ 86 Sr) are consistent with the interpretations that, although the Culebra dominates flow within the Rustler at the WIPP site and Rustler karst is not present, there has been limited vertical fluid movement within the Rustler and between the Rustler and the overlying Dewey Lake Red Beds

Single-Atom Mn Active Site in a Triol-Stabilized β-Anderson Manganohexamolybdate for Enhanced Catalytic Activity towards Adipic Acid Production

Directory of Open Access Journals (Sweden)

Jianhui Luo

2018-03-01

Full Text Available Adipic acid is an important raw chemical for the commercial production of polyamides and polyesters. The traditional industrial adipic acid production utilizes nitric acid to oxidize KA oil (mixtures of cyclohexanone and cyclohexanol, leading to the emission of N2O and thus causing ozone depletion, global warming, and acid rain. Herein, we reported an organically functionalized β-isomer of Anderson polyoxometalates (POMs nanocluster with single-atom Mn, β-{[H3NC(CH2O3]2MnMo6O18}− (1, as a highly active catalyst to selectively catalyze the oxidation of cyclohexanone, cyclohexanol, or KA oil with atom economy use of 30% H2O2 for the eco-friendly synthesis of adipic acid. The catalyst has been characterized by single crystal and powder XRD, XPS, ESI-MS, FT-IR, and NMR. A cyclohexanone (cyclohexanol conversion of >99.9% with an adipic acid selectivity of ~97.1% (~85.3% could be achieved over catalyst 1 with high turnover frequency of 2427.5 h−1 (2132.5 h−1. It has been demonstrated that the existence of Mn3+ atom active site in catalyst 1 and the special butterfly-shaped topology of POMs both play vital roles in the enhancement of catalytic activity.

Theoretical study of the dependence of single impurity Anderson model on various parameters within distributional exact diagonalization method

Science.gov (United States)

Syaina, L. P.; Majidi, M. A.

2018-04-01

Single impurity Anderson model describes a system consisting of non-interacting conduction electrons coupled with a localized orbital having strongly interacting electrons at a particular site. This model has been proven successful to explain the phenomenon of metal-insulator transition through Anderson localization. Despite the well-understood behaviors of the model, little has been explored theoretically on how the model properties gradually evolve as functions of hybridization parameter, interaction energy, impurity concentration, and temperature. Here, we propose to do a theoretical study on those aspects of a single impurity Anderson model using the distributional exact diagonalization method. We solve the model Hamiltonian by randomly generating sampling distribution of some conducting electron energy levels with various number of occupying electrons. The resulting eigenvalues and eigenstates are then used to define the local single-particle Green function for each sampled electron energy distribution using Lehmann representation. Later, we extract the corresponding self-energy of each distribution, then average over all the distributions and construct the local Green function of the system to calculate the density of states. We repeat this procedure for various values of those controllable parameters, and discuss our results in connection with the criteria of the occurrence of metal-insulator transition in this system.

Multi-site Study of Diffusion Metric Variability: Characterizing the Effects of Site, Vendor, Field Strength, and Echo Time using the Histogram Distance

Science.gov (United States)

Helmer, K. G.; Chou, M-C.; Preciado, R. I.; Gimi, B.; Rollins, N. K.; Song, A.; Turner, J.; Mori, S.

2016-01-01

MRI-based multi-site trials now routinely include some form of diffusion-weighted imaging (DWI) in their protocol. These studies can include data originating from scanners built by different vendors, each with their own set of unique protocol restrictions, including restrictions on the number of available gradient directions, whether an externally-generated list of gradient directions can be used, and restrictions on the echo time (TE). One challenge of multi-site studies is to create a common imaging protocol that will result in a reliable and accurate set of diffusion metrics. The present study describes the effect of site, scanner vendor, field strength, and TE on two common metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA). We have shown in earlier work that ROI metrics and the mean of MD and FA histograms are not sufficiently sensitive for use in site characterization. Here we use the distance between whole brain histograms of FA and MD to investigate within- and between-site effects. We concluded that the variability of DTI metrics due to site, vendor, field strength, and echo time could influence the results in multi-center trials and that histogram distance is sensitive metrics for each of these variables. PMID:27350723

Multi-site Study of Diffusion Metric Variability: Characterizing the Effects of Site, Vendor, Field Strength, and Echo Time using the Histogram Distance.

Science.gov (United States)

Helmer, K G; Chou, M-C; Preciado, R I; Gimi, B; Rollins, N K; Song, A; Turner, J; Mori, S

2016-02-27

MRI-based multi-site trials now routinely include some form of diffusion-weighted imaging (DWI) in their protocol. These studies can include data originating from scanners built by different vendors, each with their own set of unique protocol restrictions, including restrictions on the number of available gradient directions, whether an externally-generated list of gradient directions can be used, and restrictions on the echo time (TE). One challenge of multi-site studies is to create a common imaging protocol that will result in a reliable and accurate set of diffusion metrics. The present study describes the effect of site, scanner vendor, field strength, and TE on two common metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA). We have shown in earlier work that ROI metrics and the mean of MD and FA histograms are not sufficiently sensitive for use in site characterization. Here we use the distance between whole brain histograms of FA and MD to investigate within- and between-site effects. We concluded that the variability of DTI metrics due to site, vendor, field strength, and echo time could influence the results in multi-center trials and that histogram distance is sensitive metrics for each of these variables.

Effect of Chain Conformation on the Single-Molecule Melting Force in Polymer Single Crystals: Steered Molecular Dynamics Simulations Study.