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Sample records for single ion-binding site

  1. Identification of metal ion binding sites based on amino acid sequences.

    Science.gov (United States)

    Cao, Xiaoyong; Hu, Xiuzhen; Zhang, Xiaojin; Gao, Sujuan; Ding, Changjiang; Feng, Yonge; Bao, Weihua

    2017-01-01

    The identification of metal ion binding sites is important for protein function annotation and the design of new drug molecules. This study presents an effective method of analyzing and identifying the binding residues of metal ions based solely on sequence information. Ten metal ions were extracted from the BioLip database: Zn2+, Cu2+, Fe2+, Fe3+, Ca2+, Mg2+, Mn2+, Na+, K+ and Co2+. The analysis showed that Zn2+, Cu2+, Fe2+, Fe3+, and Co2+ were sensitive to the conservation of amino acids at binding sites, and promising results can be achieved using the Position Weight Scoring Matrix algorithm, with an accuracy of over 79.9% and a Matthews correlation coefficient of over 0.6. The binding sites of other metals can also be accurately identified using the Support Vector Machine algorithm with multifeature parameters as input. In addition, we found that Ca2+ was insensitive to hydrophobicity and hydrophilicity information and Mn2+ was insensitive to polarization charge information. An online server was constructed based on the framework of the proposed method and is freely available at http://60.31.198.140:8081/metal/HomePage/HomePage.html.

  2. Ion binding by humic and fulvic acids: A computational procedure based on functional site heterogeneity and the physical chemistry of polyelectrolyte solutions

    International Nuclear Information System (INIS)

    Marinsky, J.A.; Reddy, M.M.; Ephraim, J.; Mathuthu, A.

    1988-04-01

    Ion binding equilibria for humic and fulvic acids are examined from the point of view of functional site heterogeneity and the physical chemistry of polyelectrolyte solutions. A detailed explanation of the potentiometric properties of synthetic polyelectrolytes and ion-exchange gels is presented first to provide the basis for a parallel consideration of the potentiometric properties exhibited by humic and fulvic acids. The treatment is then extended to account for functional site heterogeneity. Sample results are presented for analysis of the ion-binding reactions of a standard soil fulvic acid (Armadale Horizons Bh) with this approach to test its capability for anticipation of metal ion removal from solution. The ultimate refined model is shown to be adaptable, after appropriate consideration of the heterogeneity and polyelectrolyte factors, to programming already available for the consideration of ion binding by inorganics in natural waters. (orig.)

  3. Selectivity of externally facing ion-binding sites in the Na/K pump to alkali metals and organic cations.

    Science.gov (United States)

    Ratheal, Ian M; Virgin, Gail K; Yu, Haibo; Roux, Benoît; Gatto, Craig; Artigas, Pablo

    2010-10-26

    The Na/K pump is a P-type ATPase that exchanges three intracellular Na(+) ions for two extracellular K(+) ions through the plasmalemma of nearly all animal cells. The mechanisms involved in cation selection by the pump's ion-binding sites (site I and site II bind either Na(+) or K(+); site III binds only Na(+)) are poorly understood. We studied cation selectivity by outward-facing sites (high K(+) affinity) of Na/K pumps expressed in Xenopus oocytes, under voltage clamp. Guanidinium(+), methylguanidinium(+), and aminoguanidinium(+) produced two phenomena possibly reflecting actions at site III: (i) voltage-dependent inhibition (VDI) of outwardly directed pump current at saturating K(+), and (ii) induction of pump-mediated, guanidinium-derivative-carried inward current at negative potentials without Na(+) and K(+). In contrast, formamidinium(+) and acetamidinium(+) induced K(+)-like outward currents. Measurement of ouabain-sensitive ATPase activity and radiolabeled cation uptake confirmed that these cations are external K(+) congeners. Molecular dynamics simulations indicate that bound organic cations induce minor distortion of the binding sites. Among tested metals, only Li(+) induced Na(+)-like VDI, whereas all metals tested except Na(+) induced K(+)-like outward currents. Pump-mediated K(+)-like organic cation transport challenges the concept of rigid structural models in which ion specificity at site I and site II arises from a precise and unique arrangement of coordinating ligands. Furthermore, actions by guanidinium(+) derivatives suggest that Na(+) binds to site III in a hydrated form and that the inward current observed without external Na(+) and K(+) represents cation transport when normal occlusion at sites I and II is impaired. These results provide insights on external ion selectivity at the three binding sites.

  4. Mutational analysis of divalent metal ion binding in the active site of class II α-mannosidase from sulfolobus solfataricus

    DEFF Research Database (Denmark)

    Hansen, Dennis K.; Webb, Helen; Nielsen, Jonas Willum

    2015-01-01

    Mutational analysis of Sulfolobus solfataricus class II α-mannosidase was focused on side chains that interact with the hydroxyls of the-1 mannosyl of the substrate (Asp-534) or form ligands to the active site divalent metal ion (His-228 and His-533) judged from crystal structures of homologous e......, although less dramatically with some activating metal ions. No major differences in the pH dependence between wild-type and mutant enzymes were found in the presence of different metal ions. The pH optimum was 5, but enzyme instability was observed at pH...

  5. Engineering of a calcium-ion binding site into the RC-LH1-PufX complex of Rhodobacter sphaeroides to enable ion-dependent spectral red-shifting.

    Science.gov (United States)

    Swainsbury, David J K; Martin, Elizabeth C; Vasilev, Cvetelin; Parkes-Loach, Pamela S; Loach, Paul A; Neil Hunter, C

    2017-11-01

    The reaction centre-light harvesting 1 (RC-LH1) complex of Thermochromatium (Tch.) tepidum has a unique calcium-ion binding site that enhances thermal stability and red-shifts the absorption of LH1 from 880nm to 915nm in the presence of calcium-ions. The LH1 antenna of mesophilic species of phototrophic bacteria such as Rhodobacter (Rba.) sphaeroides does not possess such properties. We have engineered calcium-ion binding into the LH1 antenna of Rba. sphaeroides by progressively modifying the native LH1 polypeptides with sequences from Tch. tepidum. We show that acquisition of the C-terminal domains from LH1 α and β of Tch. tepidum is sufficient to activate calcium-ion binding and the extent of red-shifting increases with the proportion of Tch. tepidum sequence incorporated. However, full exchange of the LH1 polypeptides with those of Tch. tepidum results in misassembled core complexes. Isolated α and β polypeptides from our most successful mutant were reconstituted in vitro with BChl a to form an LH1-type complex, which was stabilised 3-fold by calcium-ions. Additionally, carotenoid specificity was changed from spheroidene found in Rba. sphaeroides to spirilloxanthin found in Tch. tepidum, with the latter enhancing in vitro formation of LH1. These data show that the C-terminal LH1 α/β domains of Tch. tepidum behave autonomously, and are able to transmit calcium-ion induced conformational changes to BChls bound to the rest of a foreign antenna complex. Thus, elements of foreign antenna complexes, such as calcium-ion binding and blue/red switching of absorption, can be ported into Rhodobacter sphaeroides using careful design processes. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  6. The relative influence of metal ion binding sites in the I-like domain and the interface with the hybrid domain on rolling and firm adhesion by integrin alpha4beta7.

    Science.gov (United States)

    Chen, JianFeng; Takagi, Junichi; Xie, Can; Xiao, Tsan; Luo, Bing-Hao; Springer, Timothy A

    2004-12-31

    We examined the effect of conformational change at the beta(7) I-like/hybrid domain interface on regulating the transition between rolling and firm adhesion by integrin alpha(4)beta(7). An N-glycosylation site was introduced into the I-like/hybrid domain interface to act as a wedge and to stabilize the open conformation of this interface and hence the open conformation of the alpha(4) beta(7) headpiece. Wild-type alpha(4)beta(7) mediates rolling adhesion in Ca(2+) and Ca(2+)/Mg(2+) but firm adhesion in Mg(2+) and Mn(2+). Stabilizing the open headpiece resulted in firm adhesion in all divalent cations. The interaction between metal binding sites in the I-like domain and the interface with the hybrid domain was examined in double mutants. Changes at these two sites can either counterbalance one another or be additive, emphasizing mutuality and the importance of multiple interfaces in integrin regulation. A double mutant with counterbalancing deactivating ligand-induced metal ion binding site (LIMBS) and activating wedge mutations could still be activated by Mn(2+), confirming the importance of the adjacent to metal ion-dependent adhesion site (ADMIDAS) in integrin activation by Mn(2+). Overall, the results demonstrate the importance of headpiece allostery in the conversion of rolling to firm adhesion.

  7. The Relative Influence of Metal Ion Binding Sites in the I-like Domain and the Interface with the Hybrid Domain on Rolling and Firm Adhesion by Integrin α4β7*

    Science.gov (United States)

    Chen, JianFeng; Takagi, Junichi; Xie, Can; Xiao, Tsan; Luo, Bing-Hao; Springer, Timothy A.

    2015-01-01

    We examined the effect of conformational change at the β7 I-like/hybrid domain interface on regulating the transition between rolling and firm adhesion by integrin α4β7. An N-glycosylation site was introduced into the I-like/hybrid domain interface to act as a wedge and to stabilize the open conformation of this interface and hence the open conformation of the α4β7 headpiece. Wild-type α4β7 mediates rolling adhesion in Ca2+ and Ca2+/Mg2+ but firm adhesion in Mg2+ and Mn2+. Stabilizing the open headpiece resulted in firm adhesion in all divalent cations. The interaction between metal binding sites in the I-like domain and the interface with the hybrid domain was examined in double mutants. Changes at these two sites can either counterbalance one another or be additive, emphasizing mutuality and the importance of multiple interfaces in integrin regulation. A double mutant with counterbalancing deactivating ligand-induced metal ion binding site (LIMBS) and activating wedge mutations could still be activated by Mn2+, confirming the importance of the adjacent to metal ion-dependent adhesion site (ADMIDAS) in integrin activation by Mn2+. Overall, the results demonstrate the importance of headpiece allostery in the conversion of rolling to firm adhesion. PMID:15448154

  8. Metal ion binding to iron oxides

    Science.gov (United States)

    Ponthieu, M.; Juillot, F.; Hiemstra, T.; van Riemsdijk, W. H.; Benedetti, M. F.

    2006-06-01

    The biogeochemistry of trace elements (TE) is largely dependent upon their interaction with heterogeneous ligands including metal oxides and hydrous oxides of iron. The modeling of TE interactions with iron oxides has been pursued using a variety of chemical models. The objective of this work is to show that it is possible to model the adsorption of protons and TE on a crystallized oxide (i.e., goethite) and on an amorphous oxide (HFO) in an identical way. Here, we use the CD-MUSIC approach in combination with valuable and reliable surface spectroscopy information about the nature of surface complexes of the TE. The other objective of this work is to obtain generic parameters to describe the binding of the following elements (Cd, Co, Cu, Ni, Pb, and Zn) onto both iron oxides for the CD-MUSIC approach. The results show that a consistent description of proton and metal ion binding is possible for goethite and HFO with the same set of model parameters. In general a good prediction of almost all the collected experimental data sets corresponding to metal ion binding to HFO is obtained. Moreover, dominant surface species are in agreement with the recently published surface complexes derived from X-ray absorption spectroscopy (XAS) data. Until more detailed information on the structure of the two iron oxides is available, the present option seems a reasonable approximation and can be used to describe complex geochemical systems. To improve our understanding and modeling of multi-component systems we need more data obtained at much lower metal ion to iron oxide ratios in order to be able to account eventually for sites that are not always characterized in spectroscopic studies.

  9. Structure of a prokaryotic sodium channel pore reveals essential gating elements and an outer ion binding site common to eukaryotic channels.

    Science.gov (United States)

    Shaya, David; Findeisen, Felix; Abderemane-Ali, Fayal; Arrigoni, Cristina; Wong, Stephanie; Nurva, Shailika Reddy; Loussouarn, Gildas; Minor, Daniel L

    2014-01-23

    Voltage-gated sodium channels (NaVs) are central elements of cellular excitation. Notwithstanding advances from recent bacterial NaV (BacNaV) structures, key questions about gating and ion selectivity remain. Here, we present a closed conformation of NaVAe1p, a pore-only BacNaV derived from NaVAe1, a BacNaV from the arsenite oxidizer Alkalilimnicola ehrlichei found in Mono Lake, California, that provides insight into both fundamental properties. The structure reveals a pore domain in which the pore-lining S6 helix connects to a helical cytoplasmic tail. Electrophysiological studies of full-length BacNaVs show that two elements defined by the NaVAe1p structure, an S6 activation gate position and the cytoplasmic tail "neck", are central to BacNaV gating. The structure also reveals the selectivity filter ion entry site, termed the "outer ion" site. Comparison with mammalian voltage-gated calcium channel (CaV) selectivity filters, together with functional studies, shows that this site forms a previously unknown determinant of CaV high-affinity calcium binding. Our findings underscore commonalities between BacNaVs and eukaryotic voltage-gated channels and provide a framework for understanding gating and ion permeation in this superfamily. © 2013. Published by Elsevier Ltd. All rights reserved.

  10. Glutamate Water Gates in the Ion Binding Pocket of Na(+) Bound Na(+), K(+)-ATPase

    DEFF Research Database (Denmark)

    Han, Minwoo; Kopec, Wojciech; Solov'yov, Ilia A

    2017-01-01

    III is always protonated. Glutamic acid residues in the three binding sites act as water gates, and their deprotonation triggers water entry to the binding sites. From DFT calculations of Na(+) binding energies, we conclude that three protons in the binding site are needed to effectively bind Na......The dynamically changing protonation states of the six acidic amino acid residues in the ion binding pocket of the Na(+), K(+) -ATPase (NKA) during the ion transport cycle are proposed to drive ion binding, release and possibly determine Na(+) or K(+) selectivity. We use molecular dynamics (MD......(+) from water and four are needed to release them in the next step. Protonation of Asp926 in site III will induce Na(+) release, and Glu327, Glu954 and Glu779 are all likely to be protonated in the Na(+) bound occluded conformation. Our data provides key insights into the role of protons in the Na...

  11. 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

  12. The Relative Influence of Metal Ion Binding Sites in the I-like Domain and the Interface with the Hybrid Domain on Rolling and Firm Adhesion by Integrin α4β7*

    OpenAIRE

    Chen, JianFeng; Takagi, Junichi; Xie, Can; Xiao, Tsan; Luo, Bing-Hao; Springer, Timothy A.

    2004-01-01

    We examined the effect of conformational change at the β7 I-like/hybrid domain interface on regulating the transition between rolling and firm adhesion by integrin α4β7. An N-glycosylation site was introduced into the I-like/hybrid domain interface to act as a wedge and to stabilize the open conformation of this interface and hence the open conformation of the α4β7 headpiece. Wild-type α4β7 mediates rolling adhesion in Ca2+ and Ca2+/Mg2+ but firm adhesion in Mg2+ and Mn2+. Stabilizing the ope...

  13. Robotic single-site pelvic lymphadenectomy.

    Science.gov (United States)

    Tateo, Saverio; Nozza, Arrigo; Del Pezzo, Chiara; Mereu, Liliana

    2014-09-01

    To examine the feasibility of performing pelvic lymphadenectomy with robotic single site approach. Recent papers described the feasibility of robotic-single site hysterectomy [1-3] for benign and malign pathologies but only with the development of new single site 5mm instruments as the bipolar forceps, robotic single site platform can be safely utilized also for lymphadenectomy. A 65 year-old, multiparous patient with a body mass index of 22.5 and diagnosed with well differentiated adenocarcinoma of the endometrium underwent a robotic single-site peritoneal washing, total hysterectomy, bilateral adnexectomy and pelvic lymphadenectomy. The procedure was performed using the da Vinci Si Surgical System (Intuitive Surgical, Sunnyvale, CA) through a single 2,5 cm umbilical incision, with a multi-channel system and two single site robotic 5mm instruments. A 3-dimensional, HD 8.5mm endoscope and a 5mm accessory instrument were also utilized. Type I lymphonodes dissection for external iliac and obturator regions was performed [4]. Total operative time was 210 min; incision, trocar placement and docking time occurring in 12 min. Total console time was 183 min, estimated blood loss was 50 ml, no intra-operative or post-operative complications occurred. Hospital discharge occurred on post operative day 2 and total number of lymphnodes removed was 33. Difficulties in term of instrument's clashing and awkward motions have been encountered. Robotic single-site pelvic lymphadenectomy using bipolar forceps and monopolar hook is feasible. New developments are needed to improve surgical ergonomics and additional studies should be performed to explore possible benefits of this procedure. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Catalysis on singly dispersed bimetallic sites

    Science.gov (United States)

    Zhang, Shiran; Nguyen, Luan; Liang, Jin-Xia; Shan, Junjun; Liu, Jingyue; Frenkel, Anatoly I.; Patlolla, Anitha; Huang, Weixin; Li, Jun; Tao, Franklin

    2015-08-01

    A catalytic site typically consists of one or more atoms of a catalyst surface that arrange into a configuration offering a specific electronic structure for adsorbing or dissociating reactant molecules. The catalytic activity of adjacent bimetallic sites of metallic nanoparticles has been studied previously. An isolated bimetallic site supported on a non-metallic surface could exhibit a distinctly different catalytic performance owing to the cationic state of the singly dispersed bimetallic site and the minimized choices of binding configurations of a reactant molecule compared with continuously packed bimetallic sites. Here we report that isolated Rh1Co3 bimetallic sites exhibit a distinctly different catalytic performance in reduction of nitric oxide with carbon monoxide at low temperature, resulting from strong adsorption of two nitric oxide molecules and a nitrous oxide intermediate on Rh1Co3 sites and following a low-barrier pathway dissociation to dinitrogen and an oxygen atom. This observation suggests a method to develop catalysts with high selectivity.

  15. Laparoendoscopic single site in pelvic surgery

    Science.gov (United States)

    Sanchez-Salas, Rafael; Clavijo, Rafael; Barret, Eric; Sotelo, Rene

    2012-01-01

    Laparoendoscopic single site (LESS) has recently gained momentum as feasible techniques for minimal access surgery. Our aim is to describe the current status of laparoendoscopic single site (LESS) in pelvic surgery. A comprehensive revision of the literature in LESS pelvic surgery was performed. References for this manuscript were obtained by performing a review of the available literature in PubMed from 01-01-01 to 30-11-11. References outside the search period were obtained selected manuscript΄s bibliography. Search terms included: pelvic anatomy, less in gynecology, single port colectomy, urological less, single port, single site, NOTES, LESS and single incision. 314 manuscripts were initially identified. Out of these, 46 manuscripts were selected based in their pelvic anatomy or surgical content; including experimental experience, clinical series and literature reviews. LESS drastically limit the surgeon's ability to perform in the operative field and the latter becomes hardened by the lack of space in anatomical location like the pelvis. Potential advantages of LESS are gained with the understanding that the surgical procedure is more technically challenging. Pelvic surgical procedures related to colorectal surgery, gynecology and urology have been performed with LESS technique and information available is mostly represented by case reports and short case series. Comparative series remain few. LESS pelvic surgery remain in its very beginning and due to the very specific anatomical conditions further development of LESS surgery in the mentioned area can be clearly be facilitated by using robotic technology. Standardization ad reproducibility of techniques are mandatory to further develop LESS in the surgical arena.. PMID:22557719

  16. Laparoendoscopic single site in pelvic surgery

    Directory of Open Access Journals (Sweden)

    Rafael Sanchez-Salas

    2012-01-01

    Full Text Available Laparoendoscopic single site (LESS has recently gained momentum as feasible techniques for minimal access surgery. Our aim is to describe the current status of laparoendoscopic single site (LESS in pelvic surgery. A comprehensive revision of the literature in LESS pelvic surgery was performed. References for this manuscript were obtained by performing a review of the available literature in PubMed from 01-01-01 to 30-11-11. References outside the search period were obtained selected manuscript΄s bibliography. Search terms included: pelvic anatomy, less in gynecology, single port colectomy, urological less, single port, single site, NOTES, LESS and single incision. 314 manuscripts were initially identified. Out of these, 46 manuscripts were selected based in their pelvic anatomy or surgical content; including experimental experience, clinical series and literature reviews. LESS drastically limit the surgeon′s ability to perform in the operative field and the latter becomes hardened by the lack of space in anatomical location like the pelvis. Potential advantages of LESS are gained with the understanding that the surgical procedure is more technically challenging. Pelvic surgical procedures related to colorectal surgery, gynecology and urology have been performed with LESS technique and information available is mostly represented by case reports and short case series. Comparative series remain few. LESS pelvic surgery remain in its very beginning and due to the very specific anatomical conditions further development of LESS surgery in the mentioned area can be clearly be facilitated by using robotic technology. Standardization ad reproducibility of techniques are mandatory to further develop LESS in the surgical arena..

  17. Importance of diffuse metal ion binding to RNA.

    Science.gov (United States)

    Tan, Zhi-Jie; Chen, Shi-Jie

    2011-01-01

    RNAs are highly charged polyanionic molecules. RNA structure and function are strongly correlated with the ionic condition of the solution. The primary focus of this article is on the role of diffusive ions in RNA folding. Due to the long-range nature of electrostatic interactions, the diffuse ions can contribute significantly to RNA structural stability and folding kinetics. We present an overview of the experimental findings as well as the theoretical developments on the diffuse ion effects in RNA folding. This review places heavy emphasis on the effect of magnesium ions. Magnesium ions play a highly efficient role in stabilizing RNA tertiary structures and promoting tertiary structural folding. The highly efficient role goes beyond the mean-field effect such as the ionic strength. In addition to the effects of specific ion binding and ion dehydration, ion-ion correlation for the diffuse ions can contribute to the efficient role of the multivalent ions such as the magnesium ions in RNA folding.

  18. 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

  19. The study of zinc ions binding to casein.

    Science.gov (United States)

    Pomastowski, P; Sprynskyy, M; Buszewski, B

    2014-08-01

    The presented research was focused on physicochemical study of casein properties and the kinetics of zinc ions binding to the protein. Moreover, a fast and simple method of casein extraction from cow's milk has been proposed. Casein isoforms, zeta potential (ζ) and particle size of the separated caseins were characterized with the use of capillary electrophoresis, zeta potential analysis and field flow fractionation (FFF) technique, respectively. The kinetics of the metal-binding process was investigated in batch adsorption experiments. Intraparticle diffusion model, first-order and zero-order kinetic models were applied to test the kinetic experimental data. Analysis of changes in infrared bands registered for casein before and after zinc binding was also performed. The obtained results showed that the kinetic process of zinc binding to casein is not homogeneous but is expressed with an initial rapid stage with about 70% of zinc ions immobilized by casein and with a much slower second step. Maximum amount of bound zinc in the experimental conditions was 30.04mgZn/g casein. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Pyrrolo-dC Metal-Mediated Base Pairs in the Reverse Watson-Crick Double Helix: Enhanced Stability of Parallel DNA and Impact of 6-Pyridinyl Residues on Fluorescence and Silver-Ion Binding.

    Science.gov (United States)

    Yang, Haozhe; Mei, Hui; Seela, Frank

    2015-07-06

    Reverse Watson-Crick DNA with parallel-strand orientation (ps DNA) has been constructed. Pyrrolo-dC (PyrdC) nucleosides with phenyl and pyridinyl residues linked to the 6 position of the pyrrolo[2,3-d]pyrimidine base have been incorporated in 12- and 25-mer oligonucleotide duplexes and utilized as silver-ion binding sites. Thermal-stability studies on the parallel DNA strands demonstrated extremely strong silver-ion binding and strongly enhanced duplex stability. Stoichiometric UV and fluorescence titration experiments verified that a single (2py) PyrdC-(2py) PyrdC pair captures two silver ions in ps DNA. A structure for the PyrdC silver-ion base pair that aligns 7-deazapurine bases head-to-tail instead of head-to-head, as suggested for canonical DNA, is proposed. The silver DNA double helix represents the first example of a ps DNA structure built up of bidentate and tridentate reverse Watson-Crick base pairs stabilized by a dinuclear silver-mediated PyrdC pair. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Ion Binding Energies Determining Functional Transport of ClC Proteins

    Science.gov (United States)

    Yu, Tao; Guo, Xu; Zou, Xian-Wu; Sang, Jian-Ping

    2014-06-01

    The ClC-type proteins, a large family of chloride transport proteins ubiquitously expressed in biological organisms, have been extensively studied for decades. Biological function of ClC proteins can be reflected by analyzing the binding situation of Cl- ions. We investigate ion binding properties of ClC-ec1 protein with the atomic molecular dynamics simulation approach. The calculated electrostatic binding energy results indicate that Cl- at the central binding site Scen has more binding stability than the internal binding site Sint. Quantitative comparison between the latest experimental heat release data isothermal titration calorimetry (ITC) and our calculated results demonstrates that chloride ions prefer to bind at Scen than Sint in the wild-type ClC-ec1 structure and prefer to bind at Sext and Scen than Sint in mutant E148A/E148Q structures. Even though the chloride ions make less contribution to heat release when binding to Sint and are relatively unstable in the Cl- pathway, they are still part contributors for the Cl- functional transport. This work provides a guide rule to estimate the importance of Cl- at the binding sites and how chloride ions have influences on the function of ClC proteins.

  2. Calcium ion binding properties and the effect of phosphorylation on the intrinsically disordered Starmaker protein.

    Science.gov (United States)

    Wojtas, Magdalena; Hołubowicz, Rafał; Poznar, Monika; Maciejewska, Marta; Ożyhar, Andrzej; Dobryszycki, Piotr

    2015-10-27

    Starmaker (Stm) is an intrinsically disordered protein (IDP) involved in otolith biomineralization in Danio rerio. Stm controls calcium carbonate crystal formation in vivo and in vitro. Phosphorylation of Stm affects its biomineralization properties. This study examined the effects of calcium ions and phosphorylation on the structure of Stm. We have shown that CK2 kinase phosphorylates 25 or 26 residues in Stm. Furthermore, we have demonstrated that Stm's affinity for calcium binding is dependent on its phosphorylation state. Phosphorylated Stm (StmP) has an estimated 30 ± 1 calcium binding sites per protein molecule with a dissociation constant (KD) of 61 ± 4 μM, while the unphosphorylated protein has 28 ± 3 sites and a KD of 210 ± 22 μM. Calcium ion binding induces a compaction of the Stm molecule, causing a significant decrease in its hydrodynamic radius and the formation of a secondary structure. The screening effect of Na(+) ions on calcium binding was also observed. Analysis of the hydrodynamic properties of Stm and StmP showed that Stm and StmP molecules adopt the structure of native coil-like proteins.

  3. The conserved potassium channel filter can have distinct ion binding profiles: structural analysis of rubidium, cesium, and barium binding in NaK2K.

    Science.gov (United States)

    Lam, Yee Ling; Zeng, Weizhong; Sauer, David Bryant; Jiang, Youxing

    2014-08-01

    Potassium channels are highly selective for K(+) over the smaller Na(+). Intriguingly, they are permeable to larger monovalent cations such as Rb(+) and Cs(+) but are specifically blocked by the similarly sized Ba(2+). In this study, we used structural analysis to determine the binding profiles for these permeant and blocking ions in the selectivity filter of the potassium-selective NaK channel mutant NaK2K and also performed permeation experiments using single-channel recordings. Our data revealed that some ion binding properties of NaK2K are distinct from those of the canonical K(+) channels KcsA and MthK. Rb(+) bound at sites 1, 3, and 4 in NaK2K, as it does in KcsA. Cs(+), however, bound predominantly at sites 1 and 3 in NaK2K, whereas it binds at sites 1, 3, and 4 in KcsA. Moreover, Ba(2+) binding in NaK2K was distinct from that which has been observed in KcsA and MthK, even though all of these channels show similar Ba(2+) block. In the presence of K(+), Ba(2+) bound to the NaK2K channel at site 3 in conjunction with a K(+) at site 1; this led to a prolonged block of the channel (the external K(+)-dependent Ba(2+) lock-in state). In the absence of K(+), however, Ba(2+) acts as a permeating blocker. We found that, under these conditions, Ba(2+) bound at sites 1 or 0 as well as site 3, allowing it to enter the filter from the intracellular side and exit from the extracellular side. The difference in the Ba(2+) binding profile in the presence and absence of K(+) thus provides a structural explanation for the short and prolonged Ba(2+) block observed in NaK2K. © 2014 Lam et al.

  4. Zinc ions bind to and inhibit activated protein C

    DEFF Research Database (Denmark)

    Zhu, Tianqing; Ubhayasekera, Wimal; Nickolaus, Noëlle

    2010-01-01

    fold enhanced, presumably due to the Ca2+-induced conformational change affecting the conformation of the Zn2+-binding site. The inhibition mechanism was non-competitive both in the absence and presence of Ca2+. Comparisons of sequences and structures suggested several possible sites for zinc binding...

  5. Proton and metal ion binding to natural organic polyelectrolytes-I. Studies with synthetic model compounds

    Science.gov (United States)

    Marinsky, J.A.; Reddy, M.M.

    1984-01-01

    A unified physico-chemical model, based on a modified Henderson-Hasselbalch equation, for the analysis of ion complexation reactions involving charged polymeric systems is presented and verified. In this model pH = pKa+p(??Ka) + log(??/1 - ??) where Ka is the intrinsic acid dissociation constant of the ionizable functional groups on the polymer, ??Ka is the deviation of the intrinsic constant due to electrostatic interaction between the hydrogen ion and the polyanion, and alpha (??) is the polyacid degree of ionization. Using this approach pKa values for repeating acidic units of polyacrylic (PAA) and polymethacrylic (PMA) acids were found to be 4.25 ?? 0.03 and 4.8 ?? 0.1, respectively. The polyion electrostatic deviation term derived from the potentiometric titration data (i.e. p(??Ka)) is used to calculate metal ion concentration at the complexation site on the surface of the polyanion. Intrinsic cobalt-polycarboxylate binding constants (7.5 for PAA and 5.6 for PMA), obtained using this procedure, are consistent with the range of published binding constants for cobalt-monomer carboxylate complexes. In two phase systems incorporation of a Donnan membrane potential term allows determination of the intrinsic pKa of a cross-linked PMA gel, pKa = 4.83, in excellent agreement with the value obtained for the linear polyelectrolyte and the monomer. Similarly, the intrinsic stability constant for cobalt ion binding to a PMA-gel (??CoPMA+ = 11) was found to be in agreement with the linear polyelectrolyte analogue and the published data for cobalt-carboxylate monodentate complexes. ?? 1984.

  6. Robotic-assisted single-port donor nephrectomy using the da Vinci single-site platform.

    Science.gov (United States)

    LaMattina, John C; Alvarez-Casas, Josue; Lu, Irene; Powell, Jessica M; Sultan, Samuel; Phelan, Michael W; Barth, Rolf N

    2018-02-01

    Although single-port donor nephrectomy offers improved cosmetic outcomes, technical challenges have limited its application to selected centers. Our center has performed over 400 single-port donor nephrectomies. The da Vinci single-site robotic platform was utilized in an effort to overcome the steric, visualization, ergonomic, and other technical limitations associated with the single-port approach. Food and Drug Administration device exemption was obtained. Selection criteria for kidney donation included body mass index da Vinci single-site platform. Our experience supported the safety of this approach but found that the technology added cost and complexity without tangible benefit. Development of articulating instruments, energy, and stapling devices will be necessary for increased application of robotic single-site surgery for donor nephrectomy. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. On multi-site damage identification using single-site training data

    Science.gov (United States)

    Barthorpe, R. J.; Manson, G.; Worden, K.

    2017-11-01

    This paper proposes a methodology for developing multi-site damage location systems for engineering structures that can be trained using single-site damaged state data only. The methodology involves training a sequence of binary classifiers based upon single-site damage data and combining the developed classifiers into a robust multi-class damage locator. In this way, the multi-site damage identification problem may be decomposed into a sequence of binary decisions. In this paper Support Vector Classifiers are adopted as the means of making these binary decisions. The proposed methodology represents an advancement on the state of the art in the field of multi-site damage identification which require either: (1) full damaged state data from single- and multi-site damage cases or (2) the development of a physics-based model to make multi-site model predictions. The potential benefit of the proposed methodology is that a significantly reduced number of recorded damage states may be required in order to train a multi-site damage locator without recourse to physics-based model predictions. In this paper it is first demonstrated that Support Vector Classification represents an appropriate approach to the multi-site damage location problem, with methods for combining binary classifiers discussed. Next, the proposed methodology is demonstrated and evaluated through application to a real engineering structure - a Piper Tomahawk trainer aircraft wing - with its performance compared to classifiers trained using the full damaged-state dataset.

  8. Single-site neural tube closure in human embryos revisited.

    Science.gov (United States)

    de Bakker, Bernadette S; Driessen, Stan; Boukens, Bastiaan J D; van den Hoff, Maurice J B; Oostra, Roelof-Jan

    2017-10-01

    Since the multi-site closure theory was first proposed in 1991 as explanation for the preferential localizations of neural tube defects, the closure of the neural tube has been debated. Although the multi-site closure theory is much cited in clinical literature, single-site closure is most apparent in literature concerning embryology. Inspired by Victor Hamburgers (1900-2001) statement that "our real teacher has been and still is the embryo, who is, incidentally, the only teacher who is always right", we decided to critically review both theories of neural tube closure. To verify the theories of closure, we studied serial histological sections of 10 mouse embryos between 8.5 and 9.5 days of gestation and 18 human embryos of the Carnegie collection between Carnegie stage 9 (19-21 days) and 13 (28-32 days). Neural tube closure was histologically defined by the neuroepithelial remodeling of the two adjoining neural fold tips in the midline. We did not observe multiple fusion sites in neither mouse nor human embryos. A meta-analysis of case reports on neural tube defects showed that defects can occur at any level of the neural axis. Our data indicate that the human neural tube fuses at a single site and, therefore, we propose to reinstate the single-site closure theory for neural tube closure. We showed that neural tube defects are not restricted to a specific location, thereby refuting the reasoning underlying the multi-site closure theory. Clin. Anat. 30:988-999, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  9. Single site laparoscopic right hemicolectomy: an oncological feasible option

    Directory of Open Access Journals (Sweden)

    Lim Yon Kuei

    2010-09-01

    Full Text Available Abstract Introduction We present the first 7 cases of single site right hemicolectomy in Asia using the new Single Site Laparoscopy (SSL access system from Ethicon Endo-surgery. Methods Right hemicolectomy was performed using the new Single Site Laparoscopy (SSL access system. Patient demographics, operative time, histology and post operative recovery and complications were collected and analysed. Results The median operative time was 90 mins (range 60 - 150 mins and a median wound size of 2.5 cm (range 2 to 4.5 cm. The median number of lymph nodes harvested was 24 (range 20 to 34 lymph nodes. The median length of proximal margin was 70 mm (range 30 to 145 mm and that of distal margin was 50 mm (35 to 120 mm. All patients had a median hospital stay of 7 days (range 5 to 11 and there were no significant perioperative complications except for 1 patient who had a minor myocardial event. Conclusion Right hemicolectomy using SSL access system is feasible and safe for oncologic surgery.

  10. Hanford Site Welding Program Successfully Providing A Single Site Function For Use By Multiple Contractors

    International Nuclear Information System (INIS)

    Cannell, G.R.

    2009-01-01

    The Department of Energy, Richland Operations (DOE-RL) recently restructured its Hanford work scope, awarding two new contracts over the past several months for a total of three contracts to manage the sites cleanup efforts. DOE-RL met with key contractor personnel prior to and during contract transition to ensure site welding activities had appropriate oversight and maintained code compliance. The transition also provided an opportunity to establish a single site-wide function that would provide welding and materials engineering services to the Hanford site contractors: CH2M HILL Plateau Remediation Company (CHPRC); Mission Support Alliance (MSA); Washington River Protection Solutions (WRPS); and Washington Closure Hanford (WCH). Over the years, multiple and separate welding programs (amongst the several contractors) existed at the Hanford site leading to inefficiencies resulting from duplication of administrative efforts, maintenance of welding procedures, welder performance certifications, etc. The new, single program eliminates these inefficiencies. The new program, co-managed by two of the sites' new contractors, the CHPRC ('owner' of the program and responsible for construction welding services) and the MSA (provides maintenance welding services), provides more than just the traditional construction and maintenance welding services. Also provided, are welding engineering, specialty welding development/qualification for the closure of radioactive materials containers and materials evaluation/failure analysis. The following describes the new Hanford site welding program.

  11. K+ congeners that do not compromise Na+ activation of the Na+,K+-ATPase: hydration of the ion binding cavity likely controls ion selectivity.

    Science.gov (United States)

    Mahmmoud, Yasser A; Kopec, Wojciech; Khandelia, Himanshu

    2015-02-06

    The Na(+),K(+)-ATPase is essential for ionic homeostasis in animal cells. The dephosphoenzyme contains Na(+) selective inward facing sites, whereas the phosphoenzyme contains K(+) selective outward facing sites. Under normal physiological conditions, K(+) inhibits cytoplasmic Na(+) activation of the enzyme. Acetamidinium (Acet(+)) and formamidinium (Form(+)) have been shown to permeate the pump through the outward facing sites. Here, we show that these cations, unlike K(+), are unable to enter the inward facing sites in the dephosphorylated enzyme. Consistently, the organic cations exhibited little to no antagonism to cytoplasmic Na(+) activation. Na(+),K(+)-ATPase structures revealed a previously undescribed rotamer transition of the hydroxymethyl side chain of the absolutely conserved Thr(772) of the α-subunit. The side chain contributes its hydroxyl to Na(+) in site I in the E1 form and rotates to contribute its methyl group toward K(+) in the E2 form. Molecular dynamics simulations to the E1·AlF4 (-)·ADP·3Na(+) structure indicated that 1) bound organic cations differentially distorted the ion binding sites, 2) the hydroxymethyl of Thr(772) rotates to stabilize bound Form(+) through water molecules, and 3) the rotamer transition is mediated by water traffic into the ion binding cavity. Accordingly, dehydration induced by osmotic stress enhanced the interaction of the congeners with the outward facing sites and profoundly modified the organization of membrane domains of the α-subunit. These results assign a catalytic role for water in pump function, and shed light on a backbone-independent but a conformation-dependent switch between H-bond and dispersion contact as part of the catalytic mechanism of the Na(+),K(+)-ATPase. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. 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.

  13. Quaternary Benzyltriethylammonium Ion Binding to the Na,K-ATPase: a Tool to Investigate Extracellular K+ Binding Reactions†

    Science.gov (United States)

    Peluffo, R. Daniel; González-Lebrero, Rodolfo M.; Kaufman, Sergio B.; Kortagere, Sandhya; Orban, Branly; Rossi, Rolando C.; Berlin, Joshua R.

    2009-01-01

    This study examined how the quaternary organic ammonium ion, benzyltriethylamine (BTEA), binds to the Na,K-ATPase to produce membrane potential (VM)-dependent inhibition and tested the prediction that such a VM-dependent inhibitor would display electrogenic binding kinetics. BTEA competitively inhibited K+ activation of Na,K-ATPase activity and steady-state 86Rb+ occlusion. The initial rate of 86Rb+ occlusion was decreased by BTEA to a similar degree whether it was added to the enzyme prior to or simultaneously with Rb+, a demonstration that BTEA inhibits the Na,K-ATPase without being occluded. Several BTEA structural analogues reversibly inhibited Na,K-pump current, but none blocked current in a VM-dependent manner except BTEA and its para-nitro derivative, pNBTEA. Under conditions that promoted electroneutral K+-K+ exchange by the Na,K-ATPase, step changes in VM elicited pNBTEA-activated ouabain-sensitive transient currents that had similarities to those produced with the K+ congener, Tl+. pNBTEA- and Tl+-dependent transient currents both displayed saturation of charge moved at extreme negative and positive VM, equivalence of charge moved during and after step changes in VM, and similar apparent valence. The rate constant (ktot) for Tl+-dependent transient current asymptotically approached a minimum value at positive VM. In contrast, ktot for pNBTEA-dependent transient current was a “U”-shaped function of VM with a minimum value near 0 mV. Homology models of the Na,K-ATPase alpha subunit suggested that quaternary amines can bind to two extracellularly-accessible sites, one of them located at K+ binding sites positioned between transmembrane helices 4, 5, and 6. Altogether, these data revealed important information about electrogenic ion binding reactions of the Na,K-ATPase that are not directly measurable during ion transport by this enzyme. PMID:19621894

  14. 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.

  15. 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.

  16. Expressing a bacterial mercuric ion binding protein in plant for phytoremediation of heavy metals.

    Science.gov (United States)

    Hsieh, Ju-Liang; Chen, Ching-Yi; Chiu, Meng-Hsuen; Chein, Mei-Fang; Chang, Jo-Shu; Endo, Ginro; Huang, Chieh-Chen

    2009-01-30

    A specific mercuric ion binding protein (MerP) originating from transposon TnMERI1 of Bacillus megaterium strain MB1 isolated from Minamata Bay displayed good adsorption capability for a variety of heavy metals. In this study, the Gram-positive MerP protein was expressed in transgenic Arabidopsis to create a model system for phytoremediation of heavy metals. Under control of an actin promoter, the transgenic Arabidpsis showed higher tolerance and accumulation capacity for mercury, cadium and lead when compared with the control plant. Results from confocal microscopy analysis also indicate that MerP was localized at the cell membrane and vesicles of plant cells. The developed transgenic plants possessing excellent metal-accumulative ability could have potential applications in decontamination of heavy metals.

  17. 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

  18. Soil-modified carbon paste electrode: a useful tool in environmental assessment of heavy metal ion binding interactions.

    Science.gov (United States)

    Svegl, I G; Ogorevc, B

    2000-08-01

    Carbon paste electrodes (CPEs) modified with different soils in their native form were prepared to create a soil-like solid phase suitable for application in studies of heavy metal ion uptake and binding interactions. The preparation of CPEs modified with five different soils was examined and their heavy metal ion uptake behavior investigated using a model Cu(II) aqueous solution. Metal ions were accumulated under open circuit conditions and were determined after a medium exchange using differential pulse anodic stripping voltammetry, applying preelectrolysis at -0.7 V. The soil-modified CPE accumulation behavior, including the linearity of the current response versus Cu(II) concentration, the influence of the pH on the solution, and the uptake kinetics, was thoroughly investigated. The correlation between the soil-modified CPE uptake capability and the standard soil parameters, such as ion exchange capacity, soil pH, organic matter and clay content, were evaluated for all five examined soils. The influence of selected endogenous cations (K(I), Ca(II), Fe(III)) on the transfer of Cu(II) ions from a solution to the simulated soil solid phase was examined and is discussed. Preliminary examinations of the soil-modified CPE uptake behavior with some exogenous heavy metal ions of strong environmental interest (Pb(II), Hg(II), Cd(II) and Ag(I)) are also presented. This work demonstrates some attractive possibilities for the application of a soil-modified CPE in studying soil-heavy metal ion binding interactions, with a further potential use as a new environmental sensor appropriate for fist on-site testing of polluted soils.

  19. 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.

  20. 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

  1. Mixed bilayer containing dipalmitoylphosphatidylcholine and dipalmitoylphosphatidylserine: lipid complexation, ion binding, and electrostatics.

    Science.gov (United States)

    Pandit, Sagar A; Bostick, David; Berkowitz, Max L

    2003-11-01

    Two mixed bilayers containing dipalmitoylphosphatidylcholine and dipalmitoylphosphatidylserine at a ratio of 5:1 are simulated in NaCl electrolyte solutions of different concentration using the molecular dynamics technique. Direct NH.O and CH.O hydrogen bonding between lipids was observed to serve as the basis of interlipid complexation. It is deduced from our results and previous studies that dipalmitoylphosphatidylcholine alone is less likely to form interlipid complexes than in the presence of bound ions or other bilayer "impurities" such as dipalmitoylphosphatidylserine. The binding of counterions is observed and quantitated. Based upon the calculated ion binding constants, the Gouy-Chapman surface potential (theta) is calculated. In addition we calculated the electrostatic potential profile (Phi) by twice integrating the system charge distribution. A large discrepancy between and the value of Phi at the membrane surface is observed. However, at "larger" distance from the bilayer surface, a qualitative similarity in the z-profiles of Phi and psi(GC) is seen. The discrepancy between the two potential profiles near the bilayer surface is attributed to the discrete and nonbulk-like nature of water in the interfacial region and to the complex geometry of this region.

  2. Calcium ion binding to a soil fulvic acid using a Donnan Potential model

    International Nuclear Information System (INIS)

    Marinsky, J.A.

    1999-01-01

    Calcium ion binding to a soil fulvic acid (Armadale Bh Horizon) was evaluated over a range of calcium ion concentrations, from pH 3.8 to 7.3, using potentiometric titrations and calcium ion electrode measurements. Fulvic acid concentration was constant (100 milligrams per liter) and calcium ion concentration varied up to 8 x 10 -4 moles per liter. Experiments discussed here included: (1) titrations of fulvic acid-calcium ion containing solutions with sodium hydroxide; and (2) titrations of fully neutralized fulvic acid with calcium chloride solutions. Apparent binding constants (expressed as the logarithm of the value, log β app ) vary with solution pH, calcium ion concentration, degree of acid dissociation, and ionic strength (from log β app =2.5 to 3.9) and are similar to those reported by others. Fulvic acid charge, and the associated Donnan Potential, influences calcium ion-fulvic acid ion pair formation. A Donnan Potential correction term allowed calculation of intrinsic calcium ion-fulvic acid binding constants. Intrinsic binding constants vary from 1.2 to 2.5 (the average value is about log β=1.6) and are similar to, but somewhat higher than, stability constants for calcium ion-carboxylic acid monodentate complexes. (orig.)

  3. 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.

  4. 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)

  5. Robotic single-access splenectomy using the Da Vinci Single-Site® platform: a case report.

    Science.gov (United States)

    Corcione, Francesco; Bracale, Umberto; Pirozzi, Felice; Cuccurullo, Diego; Angelini, Pier Luigi

    2014-03-01

    Single-access laparoscopic splenectomy can offer patients some advantages. It has many difficulties, such as instrument clashing, lack of triangulation, odd angles and lack of space. The Da Vinci Single-Site® robotic surgery platform could decrease these difficulties. We present a case of single-access robotic splenectomy using this device. A 37 year-old female with idiopathic thrombocytopenic purpura was operated on with a single-site approach, using the Da Vinci Single-Site robotic surgery device. The procedure was successfully completed in 140 min. No intraoperative and postoperative complications occurred. The patient was discharged from hospital on day 3. Single-access robotic splenectomy seems to be feasible and safe using the new robotic single-access platform, which seems to overcome certain limits of previous robotic or conventional single-access laparoscopy. We think that additional studies should also be performed to explore the real cost-effectiveness of the platform. Copyright © 2013 John Wiley & Sons, Ltd.

  6. 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 ...

  7. IBiSA_Tools: A Computational Toolkit for Ion-Binding State Analysis in Molecular Dynamics Trajectories of Ion Channels.

    Directory of Open Access Journals (Sweden)

    Kota Kasahara

    Full Text Available Ion conduction mechanisms of ion channels are a long-standing conundrum. Although the molecular dynamics (MD method has been extensively used to simulate ion conduction dynamics at the atomic level, analysis and interpretation of MD results are not straightforward due to complexity of the dynamics. In our previous reports, we proposed an analytical method called ion-binding state analysis to scrutinize and summarize ion conduction mechanisms by taking advantage of a variety of analytical protocols, e.g., the complex network analysis, sequence alignment, and hierarchical clustering. This approach effectively revealed the ion conduction mechanisms and their dependence on the conditions, i.e., ion concentration and membrane voltage. Here, we present an easy-to-use computational toolkit for ion-binding state analysis, called IBiSA_tools. This toolkit consists of a C++ program and a series of Python and R scripts. From the trajectory file of MD simulations and a structure file, users can generate several images and statistics of ion conduction processes. A complex network named ion-binding state graph is generated in a standard graph format (graph modeling language; GML, which can be visualized by standard network analyzers such as Cytoscape. As a tutorial, a trajectory of a 50 ns MD simulation of the Kv1.2 channel is also distributed with the toolkit. Users can trace the entire process of ion-binding state analysis step by step. The novel method for analysis of ion conduction mechanisms of ion channels can be easily used by means of IBiSA_tools. This software is distributed under an open source license at the following URL: http://www.ritsumei.ac.jp/~ktkshr/ibisa_tools/.

  8. Calcium ion binding properties of Medicago truncatula calcium/calmodulin-dependent protein kinase.

    Science.gov (United States)

    Swainsbury, David J K; Zhou, Liang; Oldroyd, Giles E D; Bornemann, Stephen

    2012-09-04

    A calcium/calmodulin-dependent protein kinase (CCaMK) is essential in the interpretation of calcium oscillations in plant root cells for the establishment of symbiotic relationships with rhizobia and mycorrhizal fungi. Some of its properties have been studied in detail, but its calcium ion binding properties and subsequent conformational change have not. A biophysical approach was taken with constructs comprising either the visinin-like domain of Medicago truncatula CCaMK, which contains EF-hand motifs, or this domain together with the autoinhibitory domain. The visinin-like domain binds three calcium ions, leading to a conformational change involving the exposure of hydrophobic surfaces and a change in tertiary but not net secondary or quaternary structure. The affinity for calcium ions of visinin-like domain EF-hands 1 and 2 (K(d) = 200 ± 50 nM) was appropriate for the interpretation of calcium oscillations (~125-850 nM), while that of EF-hand 3 (K(d) ≤ 20 nM) implied occupancy at basal calcium ion levels. Calcium dissociation rate constants were determined for the visinin-like domain of CCaMK, M. truncatula calmodulin 1, and the complex between these two proteins (the slowest of which was 0.123 ± 0.002 s(-1)), suggesting the corresponding calcium association rate constants were at or near the diffusion-limited rate. In addition, the dissociation of calmodulin from the protein complex was shown to be on the same time scale as the dissociation of calcium ions. These observations suggest that the formation and dissociation of the complex between calmodulin and CCaMK would substantially mirror calcium oscillations, which typically have a 90 s periodicity.

  9. Site characterization and validation - geophysical single hole logging. Stage 1

    International Nuclear Information System (INIS)

    Fridh, B.

    1987-12-01

    Five 'boundary boreholes' have been drilled for preliminary characterization of a previously unexplored site at the 360 m level in the Stripa mine. Three of these boreholes are directed towards the North in the mine coordinate system, while two are directed towards the West. Furthermore, a vertical hole has been drilled at the end of the 3D-migration drift. To adequately describe the rock mass in the vicinity of these boreholes, a comprehensive program utilizing a large number of geophysical borehole methods has been carried out. The specific geophysical character of the rock mass and the major deformed units distinguished in the boreholes are recognized, and in certain cases also correlated between the boreholes. (orig.)

  10. Site-Selection in Single-Molecule Junction for Highly Reproducible Molecular Electronics.

    Science.gov (United States)

    Kaneko, Satoshi; Murai, Daigo; Marqués-González, Santiago; Nakamura, Hisao; Komoto, Yuki; Fujii, Shintaro; Nishino, Tomoaki; Ikeda, Katsuyoshi; Tsukagoshi, Kazuhito; Kiguchi, Manabu

    2016-02-03

    Adsorption sites of molecules critically determine the electric/photonic properties and the stability of heterogeneous molecule-metal interfaces. Then, selectivity of adsorption site is essential for development of the fields including organic electronics, catalysis, and biology. However, due to current technical limitations, site-selectivity, i.e., precise determination of the molecular adsorption site, remains a major challenge because of difficulty in precise selection of meaningful one among the sites. We have succeeded the single site-selection at a single-molecule junction by performing newly developed hybrid technique: simultaneous characterization of surface enhanced Raman scattering (SERS) and current-voltage (I-V) measurements. The I-V response of 1,4-benzenedithiol junctions reveals the existence of three metastable states arising from different adsorption sites. Notably, correlated SERS measurements show selectivity toward one of the adsorption sites: "bridge sites". This site-selectivity represents an essential step toward the reliable integration of individual molecules on metallic surfaces. Furthermore, the hybrid spectro-electric technique reveals the dependence of the SERS intensity on the strength of the molecule-metal interaction, showing the interdependence between the optical and electronic properties in single-molecule junctions.

  11. 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.

  12. 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 ...

  13. 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.

  14. Robotic Laparoendoscopic Single-site Retroperitioneal Renal Surgery: Initial Investigation of a Purpose-built Single-port Surgical System.

    Science.gov (United States)

    Maurice, Matthew J; Ramirez, Daniel; Kaouk, Jihad H

    2017-04-01

    Robotic single-site retroperitoneal renal surgery has the potential to minimize the morbidity of standard transperitoneal and multiport approaches. Traditionally, technological limitations of non-purpose-built robotic platforms have hindered the application of this approach. To assess the feasibility of retroperitoneal renal surgery using a new purpose-built robotic single-port surgical system. This was a preclinical study using three male cadavers to assess the feasibility of the da Vinci SP1098 surgical system for robotic laparoendoscopic single-site (R-LESS) retroperitoneal renal surgery. We used the SP1098 to perform retroperitoneal R-LESS radical nephrectomy (n=1) and bilateral partial nephrectomy (n=4) on the anterior and posterior surfaces of the kidney. Improvements unique to this system include enhanced optics and intelligent instrument arm control. Access was obtained 2cm anterior and inferior to the tip of the 12th rib using a novel 2.5-cm robotic single-port system that accommodates three double-jointed articulating robotic instruments, an articulating camera, and an assistant port. The primary outcome was the technical feasibility of the procedures, as measured by the need for conversion to standard techniques, intraoperative complications, and operative times. All cases were completed without the need for conversion. There were no intraoperative complications. The operative time was 100min for radical nephrectomy, and the mean operative time was 91.8±18.5min for partial nephrectomy. Limitations include the preclinical model, the small sample size, and the lack of a control group. Single-site retroperitoneal renal surgery is feasible using the latest-generation SP1098 robotic platform. While the potential of the SP1098 appears promising, further study is needed for clinical evaluation of this investigational technology. In an experimental model, we used a new robotic system to successfully perform major surgery on the kidney through a single small

  15. Formation of Mixed-Ligand Complexes of Pd2+ with Nucleoside 5'-Monophosphates and Some Metal-Ion-Binding Nucleoside Surrogates

    Directory of Open Access Journals (Sweden)

    Oleg Golubev

    2014-10-01

    Full Text Available Formation of mixed-ligand Pd2+ complexes between canonical nucleoside 5'-monophosphates and five metal-ion-binding nucleoside analogs has been studied by 1H-NMR spectroscopy to test the ability of these nucleoside surrogates to discriminate between unmodified nucleobases by Pd2+-mediated base pairing. The nucleoside analogs studied included 2,6-bis(3,5-dimethylpyrazol-1-yl-, 2,6-bis(1-methylhydrazinyl- and 6-(3,5-dimethylpyrazol-1-yl-substituted 9-(β-d-ribofuranosylpurines 1–3, and 2,4-bis(3,5-dimethylpyrazol-1-yl- and 2,4-bis(1-methylhydrazinyl-substituted 5-(β-d-ribofuranosyl-pyrimidines 4–5. Among these, the purine derivatives 1-3 bound Pd2+ much more tightly than the pyrimidine derivatives 4, 5 despite apparently similar structures of the potential coordination sites. Compounds 1 and 2 formed markedly stable mixed-ligand Pd2+ complexes with UMP and GMP, UMP binding favored by 1 and GMP by 2. With 3, formation of mixed-ligand complexes was retarded by binding of two molecules of 3 to Pd2+.

  16. 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....

  17. Robotic right colectomy using the Da Vinci Single-Site® platform: case report.

    Science.gov (United States)

    Morelli, Luca; Guadagni, Simone; Caprili, Giovanni; Di Candio, Giulio; Boggi, Ugo; Mosca, Franco

    2013-09-01

    While single-port laparoscopy for abdominal surgery is technically challenging, the Da Vinci Single-Site® robotic surgery platform may help to overcome some of the difficulties of this rapidly evolving technique. The authors of this article present a case of single-incision, robotic right colectomy using this device. A 74-year-old female with malignant polyp of caecum was operated on with a single-site approach using the Da Vinci Single-Site® robotic surgery device. Resection and anastomosis were performed extra-corporeally after undocking the robot. The procedure was successfully completed in 200 min. No surgical complications occurred during the intervention and the post-operative stay and no conversion to laparotomy or additional trocars were required. To the best of our knowledge, this is the first case of right colectomy using the Da Vinci Single-Site® robotic surgery platform to be reported. The procedure is feasible and safe and its main advantages are restoration of triangulation and reduced instrument clashes. Copyright © 2013 John Wiley & Sons, Ltd.

  18. 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.

  19. Da Vinci single site© surgical platform in clinical practice: a systematic review.

    Science.gov (United States)

    Morelli, Luca; Guadagni, Simone; Di Franco, Gregorio; Palmeri, Matteo; Di Candio, Giulio; Mosca, Franco

    2016-12-01

    The Da Vinci single-site© surgical platform (DVSSP) is a set of single-site instruments and accessories specifically dedicated to robot-assisted single-site surgery. The PubMed database from inception to June 2015 was searched for English literature on the clinical use of DVSSP in general surgery, urology and gynecology. Twenty-nine articles involving the clinical application of DVSSP were identified; 15 articles on general surgery (561 procedures), four articles on urology (48 procedures) and 10 articles on gynecology (212 procedures). All studies have proven the safety and feasibility of the use of DVSSP. The principal reported advantage is the restoration of intra-abdominal triangulation, while the main reported limitation is the lack of the endowrist. Da Vinci systems have proven to be valuable assets in single-site surgery, owing to the combination of robot use with the dedicated single-incision platform. However, case-control or prospective trials are warranted to draw more definitive conc lusions. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  20. Single versus Two-Site Phacoemulsification and Mitomycin-C Trabeculectomy

    Directory of Open Access Journals (Sweden)

    Alireza Baradaran-Rafiee

    2008-11-01

    Full Text Available

    PURPOSE: To compare the outcomes of single-site versus two-site mitomycin-C (MMC augmented phacotrabeculectomy. METHODS: This matched randomized clinical trial included 34 eyes of 30 patients with visually significant cataracts and poorly controlled glaucoma. Equal numbers of eyes were randomly assigned to the single-site and two-site groups. In the single-site approach, phacoemulsification was performed under a superior scleral tunnel followed by trabeculectomy. The two-site approach included a temporal clear corneal phaco-emulsification combined with a separate superior trabeculectomy. MMC 0.2 mg/ml was similarly applied for one minute in both groups. RESULTS: Patients were followed for a mean period of 13±1.4 (range, 12 to 15 months. Mean best corrected visual acuity one year after surgery was 0.6±0.4 LogMAR in the single-site group and 0.4±0.28 LogMAR in the two-site group (P=0.12. In the single-site group, mean preoperative intraocular pressure (IOP was 26.4±6.6 mmHg which was decreased to 14.8±2.5 mmHg, one year after the operation (P < 0.001. Corresponding figures for the two-site group were 22.9±3.3 and 13.6±1.7 mmHg respectively (P < 0.001. At final follow up no significant difference in IOP existed between the study groups. Mean number of anti-glaucoma medications was 0.06±0.24 in the two-site group vs 0

  1. 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...

  2. 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.

  3. The use of isothermal titration calorimetry to determine the thermodynamics of metal ion binding to low-cost sorbents

    International Nuclear Information System (INIS)

    Karlsen, Vigdis; Heggset, Ellinor Baevre; Sorlie, Morten

    2010-01-01

    The thermodynamics of Al 3+ , Cr 3+ , and Pb 2+ binding to the abundant biopolymer chitin have been determined using isothermal titration calorimetry (ITC) and compared to what is observed for binding to activated carbon. The use of ITC enables the detection of two distinct binding sites on chitin for all three metal ions. For the relative strong binding sites, free energy changes ranges from -37.6 kJ/mol to -41.8 kJ/mol while the same values are from -30.1 kJ/mol to -31.8 kJ/mol for the relative weak binding sites. All binding reactions to chitin are entropically driven. Interactions of the metal ions to activated carbon are best fitted as a single-site binding with relative weak binding with free energy changes from -26.3 kJ/mol to -26.8 kJ/mol.

  4. Development and validation of the Single Item Trait Empathy Scale (SITES).

    Science.gov (United States)

    Konrath, Sara; Meier, Brian P; Bushman, Brad J

    2018-04-01

    Empathy involves feeling compassion for others and imagining how they feel. In this article, we develop and validate the Single Item Trait Empathy Scale (SITES), which contains only one item that takes seconds to complete. In seven studies (N=5,724), the SITES was found to be both reliable and valid. It correlated in expected ways with a wide variety of intrapersonal outcomes. For example, it is negatively correlated with narcissism, depression, anxiety, and alexithymia. In contrast, it is positively correlated with other measures of empathy, self-esteem, subjective well-being, and agreeableness. The SITES also correlates with a wide variety of interpersonal outcomes, especially compassion for others and helping others. The SITES is recommended in situations when time or question quantity is constrained.

  5. 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

  6. Micro-analysis of plaque fluid from single-site fasted plaque

    International Nuclear Information System (INIS)

    Vogel, G.L.; Carey, C.M.; Chow, L.C.; Tatevossian, A.

    1990-01-01

    Despite the site-specific nature of caries, nearly all data on the concentration of ions relevant to the level of saturation of plaque fluid with respect to calcium phosphate minerals or enamel are from studies that used pooled samples. A procedure is described for the collection and analysis of inorganic ions relevant to these saturation levels in plaque fluid samples collected from a single surface on a single tooth. Various methods for examining data obtained by this procedure are described, and a mathematical procedure employing potential plots is recommended

  7. 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...

  8. 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.

  9. 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)

  10. 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.

  11. 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.

  12. 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.

  13. Minimal invasive single-site surgery in colorectal procedures: Current state of the art

    Directory of Open Access Journals (Sweden)

    Diana Michele

    2011-01-01

    Full Text Available Background: Minimally invasive single-site (MISS surgery has recently been applied to colorectal surgery. We aimed to assess the current state of the art and the adequacy of preliminary oncological results. Methods: We performed a systematic review of the literature using Pubmed, Medline, SCOPUS and Web of Science databases. Keywords used were "Single Port" or "Single-Incision" or "LaparoEndoscopic Single Site" or "SILS™" and "Colon" or "Colorectal" and "Surgery". Results: Twenty-nine articles on colorectal MISS surgery have been published from July 2008 to July 2010, presenting data on 149 patients. One study reported analgesic requirement. The final incision length ranged from 2.5 to 8 cm. Only two studies reported fascial incision length. There were two port site hernias in a series of 13 patients (15.38%. Two "fully laparoscopic" MISS procedures with preparation and achievement of the anastomosis completely intracorporeally are reported. Future site of ileostomy was used as the sole access for the procedures in three studies. Lymph node harvesting, resection margins and length of specimen were sufficient in oncological cases. Conclusions: MISS colorectal surgery is a challenging procedure that seems to be safe and feasible, but the existing clinical evidence is limited. In selected cases, and especially when an ileostomy is planned, colorectal surgery may be an ideal indication for MISS surgery leading to a no-scar surgery. Despite preliminary oncological results showing the feasibility of MISS surgery, we want to stress the need to standardize the technique and carefully evaluate its application in oncosurgery under ethical committee control.

  14. 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.

  15. 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.

  16. 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

  17. 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

  18. 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.

  19. Understanding Ion Binding Affinity and Selectivity in β-Parvalbumin Using Molecular Dynamics and Mean Spherical Approximation Theory.

    Science.gov (United States)

    Kucharski, Amir N; Scott, Caitlin E; Davis, Jonathan P; Kekenes-Huskey, Peter M

    2016-08-25

    Parvalbumin (PV) is a globular calcium (Ca(2+))-selective protein expressed in a variety of biological tissues. Our computational studies of the rat β-parvalbumin (β-PV) isoform seek to elucidate the molecular thermodynamics of Ca(2+) versus magnesium (Mg(2+)) binding at the protein's two EF-hand motifs. Specifically, we have utilized molecular dynamics (MD) simulations and a mean-field electrolyte model (mean spherical approximation (MSA) theory) to delineate how the EF-hand scaffold controls the "local" thermodynamics of Ca(2+) binding selectivity over Mg(2+). Our MD simulations provide the probability density of metal-chelating oxygens within the EF-hand scaffolds for both Ca(2+) and Mg(2+), as well the conformational strain induced by Mg(2+) relative to Ca(2+) binding. MSA theory utilizes the binding domain oxygen and charge distributions to predict the chemical potential of ion binding, as well as their corresponding concentrations within the binding domain. We find that the electrostatic and steric contributions toward ion binding were similar for Mg(2+) and Ca(2+), yet the latter was 5.5 kcal/mol lower in enthalpy when internal strain within the EF hand was considered. We therefore speculate that beyond differences in dehydration energies for the Ca(2+) versus Mg(2+), strain induced in the β-PV EF hand by cation binding significantly contributes to the nearly 10,000-fold difference in binding affinity reported in the literature. We further complemented our analyses of local factors governing cation binding selectivity with whole-protein (global) contributions, such as interhelical residue-residue contacts and solvent exposure of hydrophobic surface. These contributions were found to be comparable for both Ca(2+)- and Mg(2+)-bound β-PV, which may implicate local factors, EF-hand strain, and dehydration, in providing the primary means of selectivity. We anticipate these methods could be used to estimate metal binding thermodynamics across a broad range of

  20. 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.

  1. 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

  2. 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, (Oc)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 MoOx Tmax of reduction reported to date, suggesting a highly reactive MoVI center. (Oc)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. (Oc)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.

  3. 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.

  4. 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.

  5. 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...

  6. 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.

  7. 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.

  8. 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

  9. 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

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. 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

  18. 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

  19. 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

  20. [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.

  1. 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

  2. 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

  3. 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.

  4. 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}.

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. 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.

  16. 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.)

  17. 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.)

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. 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....

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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

  14. 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

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

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

    KAUST Repository

    Kadoura, Ahmad Salim; Siripatana, Adil; Sun, Shuyu; Knio, Omar; Hoteit, Ibrahim

    2016-01-01

    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

  1. A Single-hole stone anchor from Kottapatnam: Early historic port site of Andhra Pradesh, India

    Digital Repository Service at National Institute of Oceanography (India)

    Tripati, S.; Rao, K.P.; Kumari, S.; Imsong, O.; Vanlalhruaitluangi, V.

    of Kottapatnam and this is the first stone anchor reported from Andhra coast. In this paper the single hole stone anchor has been detailed along with its probable period and the trade contacts of Kottapatnam as a port...

  2. GenProBiS: web server for mapping of sequence variants to protein binding sites.

    Science.gov (United States)

    Konc, Janez; Skrlj, Blaz; Erzen, Nika; Kunej, Tanja; Janezic, Dusanka

    2017-07-03

    Discovery of potentially deleterious sequence variants is important and has wide implications for research and generation of new hypotheses in human and veterinary medicine, and drug discovery. The GenProBiS web server maps sequence variants to protein structures from the Protein Data Bank (PDB), and further to protein-protein, protein-nucleic acid, protein-compound, and protein-metal ion binding sites. The concept of a protein-compound binding site is understood in the broadest sense, which includes glycosylation and other post-translational modification sites. Binding sites were defined by local structural comparisons of whole protein structures using the Protein Binding Sites (ProBiS) algorithm and transposition of ligands from the similar binding sites found to the query protein using the ProBiS-ligands approach with new improvements introduced in GenProBiS. Binding site surfaces were generated as three-dimensional grids encompassing the space occupied by predicted ligands. The server allows intuitive visual exploration of comprehensively mapped variants, such as human somatic mis-sense mutations related to cancer and non-synonymous single nucleotide polymorphisms from 21 species, within the predicted binding sites regions for about 80 000 PDB protein structures using fast WebGL graphics. The GenProBiS web server is open and free to all users at http://genprobis.insilab.org. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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....

  8. 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.

  9. 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.

  10. 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.

  11. 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)

  12. Geology Data Package for the Single-Shell Tank Waste Management Areas at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Reidel, Steve P.; Chamness, Mickie A.

    2007-01-01

    This data package discusses the geology of the single-shell tank (SST) farms and the geologic history of the area. The focus of this report is to provide the most recent geologic information available for the SST farms. This report builds upon previous reports on the tank farm geology and Integrated Disposal Facility geology with information available after those reports were published.

  13. 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.

  14. Multiple nucleophilic elbows leading to multiple active sites in a single module esterase from Sorangium cellulosum

    DEFF Research Database (Denmark)

    Udatha, D.B.R.K. Gupta; Madsen, Karina Marie; Panagiotou, Gianni

    2015-01-01

    The catalytic residues in carbohydrate esterase enzyme families constitute a highly conserved triad: serine, histidine and aspartic acid. This catalytic triad is generally located in a very sharp turn of the protein backbone structure, called the nucleophilic elbow and identified by the consensus...... sequence GXSXG. An esterase from Sorangium cellulosum Soce56 that contains five nucleophilic elbows was cloned and expressed in Escherichia coli and the function of each nucleophilic elbowed site was characterized. In order to elucidate the function of each nucleophilic elbow, site directed mutagenesis....... To our knowledge, this is the first report presenting the role of multiple nucleophilic elbows in the catalytic promiscuity of an esterase. Further structural analysis at protein unit level indicates the new evolutionary trajectories in emerging promiscuous esterases....

  15. Laparoendoscopic Single-Site Surgery for the Treatment of Benign Adnexal Disease: A Prospective Trial

    Directory of Open Access Journals (Sweden)

    Anna Fagotti

    2010-01-01

    Full Text Available Background. To validate feasibility, efficacy, and safeness of laparoscopic treatment of benign adnexal diseases through a single transumbilical access (LESS in a prospective series of patients. Methods. A prospective clinical trial including 30 women has been conducted at the Division of Gynecology of Catholic University of Sacred Hearth of Rome. Patients underwent different laparoscopic procedures by LESS utilizing a multiport trocar and conventional straight laparoscopic instrumentation. Intra and perioperative outcome has been reported. Results. Ten mono/bilateral adnexectomies and 20 cystectomies have been performed by LESS approach. Laparoscopic procedures were completed through a single access in 28 cases (93.4%. No major intra- or postoperative complications were observed. Mean hospital stay was 1.3 days. Conclusions. LESS approach is feasible to treat benign adnexal disease with a very low conversion rate and no early or late complications. More clinical data are needed to confirm these advantages compared to standard laparoscopic technique.

  16. Assessment of single-shell tank residual-liquid issues at Hanford Site, Washington

    International Nuclear Information System (INIS)

    Murthy, K.S.; Stout, L.A.; Napier, B.A.; Reisenauer, A.E.; Landstrom, D.K.

    1983-06-01

    This report provides an assessment of the overall effectiveness and implications of jet pumping the interstitial liquids (IL) from single-shell tanks at Hanford. The jet-pumping program, currently in progress at Hanford, involves the planned removal of IL contained in 89 of the 149 single-shell tanks and its transfer to double-shell tanks after volume reduction by evaporation. The purpose of this report is to estimate the public and worker doses associated with (1) terminating pumping immediately, (2) pumping to a 100,000-gal limit per tank, (3) pumping to a 50,000-gal limit per tank, and (4) pumping to the maximum practical liquid removal level of 30,000 gal. Assessment of the cost-effectiveness of these various levels of pumping in minimizing any undue health and safety risks to the public or worker is also presented

  17. 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.

  18. Photoemission and electron-stimulated desorption studies of H on W(110): Single- versus two-binding-site models

    International Nuclear Information System (INIS)

    Weng, S.

    1982-01-01

    The chemisorption of H on W(110) at room temperature is studied with the use of angle-integrated photoemission and electron-stimulated desorption (ESD). The ESD cross sections of H + are found to be sol low that no significant H + signals with meaningful ion energy distributions are observed. The photoemission results show, however, two types of H adatoms, referred to as β 2 and β 1 states, for this chemisorptive system. Both states are found to appear simultaneously rather than sequentially as suggested by previous studies, and exhibit a simple 1-theta adsorption kinetics with different initial sticking coefficients. The β 2 state induces two binding energy levels at -2.0 and -6.0 eV, respectively, whereas the β 1 state induces a level at -3.8 eV. The work-function change (with a maximum value of -0.45 eV) is found to follow exactly with the intensity of the β 2 state. These results are found to be compatible with the two-binding-site model, inherently suggested by the reflection high-enery electron-diffraction data. However, the results can also be consistent with a single-binding-site model suggested by a recent angle-resolved photoemission and inelastic electron scattering study. A model based on the present results is proposed and critically compared with previous studies. Unresolved problems associated with both single- and two-binding-site models are also discussed

  19. 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

  20. Single cobalt sites in mesoporous N-doped carbon matrix for selective catalytic hydrogenation of nitroarenes

    KAUST Repository

    Sun, Xiaohui

    2017-11-20

    A supported cobalt catalyst with atomically dispersed Co-Nx sites (3.5 wt% Co) in a mesoporous N-doped carbon matrix (named Co@mesoNC) is synthesized by hydrolysis of tetramethyl orthosilicate (TMOS) in a Zn/Co bimetallic zeolitic imidazolate framework (BIMZIF(Co,Zn)), followed by high-temperature pyrolysis and SiO2 leaching. A combination of TEM, XRD XPS and X-ray absorption spectroscopy studies confirm the absence of cobalt nanoparticles and indicate that these highly dispersed cobalt species are present in the form of Co-Nx. The exclusive formation of Co-Nx sites in the carbon matrix is attributed to the presence of a large amount of Zn and N in the BIMZIF precursor together with the presence of SiO2 in the pore space of this framework, extending the initial spatial distance between cobalt atoms and thereby impeding their agglomeration. The presence of SiO2 during high-temperature pyrolysis is proven crucial to create mesoporosity and a high BET area and pore volume in the N-doped carbon support (1780 m2 g−1, 1.54 cm3 g−1). This heterogeneous Co@mesoNC catalyst displays high activity and selectivity (>99%) for the selective hydrogenation of nitrobenzene to aniline at mild conditions (0.5–3 MPa, 343–383 K). When more challenging substrates (functionalized nitroarenes) are hydrogenated, the catalyst Co@mesoNC displays an excellent chemoselectivity to the corresponding substituted anilines.The presence of mesoporosity improves mass transport of reactants and/or products and the accessibility of the active Co-Nx sites, and greatly reduces deactivation due to fouling.

  1. Single cobalt sites in mesoporous N-doped carbon matrix for selective catalytic hydrogenation of nitroarenes

    KAUST Repository

    Sun, Xiaohui; Olivos-Suarez, Alma I.; Osadchii, Dmitrii; Romero, Maria Jose Valero; Kapteijn, Freek; Gascon, Jorge

    2017-01-01

    A supported cobalt catalyst with atomically dispersed Co-Nx sites (3.5 wt% Co) in a mesoporous N-doped carbon matrix (named Co@mesoNC) is synthesized by hydrolysis of tetramethyl orthosilicate (TMOS) in a Zn/Co bimetallic zeolitic imidazolate framework (BIMZIF(Co,Zn)), followed by high-temperature pyrolysis and SiO2 leaching. A combination of TEM, XRD XPS and X-ray absorption spectroscopy studies confirm the absence of cobalt nanoparticles and indicate that these highly dispersed cobalt species are present in the form of Co-Nx. The exclusive formation of Co-Nx sites in the carbon matrix is attributed to the presence of a large amount of Zn and N in the BIMZIF precursor together with the presence of SiO2 in the pore space of this framework, extending the initial spatial distance between cobalt atoms and thereby impeding their agglomeration. The presence of SiO2 during high-temperature pyrolysis is proven crucial to create mesoporosity and a high BET area and pore volume in the N-doped carbon support (1780 m2 g−1, 1.54 cm3 g−1). This heterogeneous Co@mesoNC catalyst displays high activity and selectivity (>99%) for the selective hydrogenation of nitrobenzene to aniline at mild conditions (0.5–3 MPa, 343–383 K). When more challenging substrates (functionalized nitroarenes) are hydrogenated, the catalyst Co@mesoNC displays an excellent chemoselectivity to the corresponding substituted anilines.The presence of mesoporosity improves mass transport of reactants and/or products and the accessibility of the active Co-Nx sites, and greatly reduces deactivation due to fouling.

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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

  7. 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

  8. 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.

  9. A semi-grand canonical Monte Carlo simulation model for ion binding to ionizable surfaces: proton binding of carboxylated latex particles as a case study.

    Science.gov (United States)

    Madurga, Sergio; Rey-Castro, Carlos; Pastor, Isabel; Vilaseca, Eudald; David, Calin; Garcés, Josep Lluís; Puy, Jaume; Mas, Francesc

    2011-11-14

    In this paper, we present a computer simulation study of the ion binding process at an ionizable surface using a semi-grand canonical Monte Carlo method that models the surface as a discrete distribution of charged and neutral functional groups in equilibrium with explicit ions modelled in the context of the primitive model. The parameters of the simulation model were tuned and checked by comparison with experimental titrations of carboxylated latex particles in the presence of different ionic strengths of monovalent ions. The titration of these particles was analysed by calculating the degree of dissociation of the latex functional groups vs. pH curves at different background salt concentrations. As the charge of the titrated surface changes during the simulation, a procedure to keep the electroneutrality of the system is required. Here, two approaches are used with the choice depending on the ion selected to maintain electroneutrality: counterion or coion procedures. We compare and discuss the difference between the procedures. The simulations also provided a microscopic description of the electrostatic double layer (EDL) structure as a function of pH and ionic strength. The results allow us to quantify the effect of the size of the background salt ions and of the surface functional groups on the degree of dissociation. The non-homogeneous structure of the EDL was revealed by plotting the counterion density profiles around charged and neutral surface functional groups. © 2011 American Institute of Physics

  10. Covalent modifications of the amyloid beta peptide by hydroxynonenal: Effects on metal ion binding by monomers and insights into the fibril topology.

    Science.gov (United States)

    Grasso, G; Komatsu, H; Axelsen, P H

    2017-09-01

    Amyloid β peptides (Aβ) and metal ions are associated with oxidative stress in Alzheimer's disease (AD). Oxidative stress, acting on ω-6 polyunsaturated fatty acyl chains, produces diverse products, including 4-hydroxy-2-nonenal (HNE), which can covalently modify the Aβ that helped to produce it. To examine possible feedback mechanisms involving Aβ, metal ions and HNE production, the effects of HNE modification and fibril formation on metal ion binding was investigated. Results indicate that copper(II) generally inhibits the modification of His side chains in Aβ by HNE, but that once modified, copper(II) still binds to Aβ with high affinity. Fibril formation protects only one of the three His residues in Aβ from HNE modification, and this protection is consistent with proposed models of fibril structure. These results provide insight into a network of biochemical reactions that may be operating as a consequence of oxidative stress in AD, or as part of the pathogenic process. Copyright © 2016. Published by Elsevier Inc.

  11. Bacterial exopolysaccharides as a modern biotechnological tool for modification of fungal laccase properties and metal ion binding.

    Science.gov (United States)

    Osińska-Jaroszuk, Monika; Jaszek, Magdalena; Starosielec, Magdalena; Sulej, Justyna; Matuszewska, Anna; Janczarek, Monika; Bancerz, Renata; Wydrych, Jerzy; Wiater, Adrian; Jarosz-Wilkołazka, Anna

    2018-03-26

    Four bacterial EPSs extracted from Rhizobium leguminosarum bv. trifolii Rt24.2, Sinorhizobium meliloti Rm1021, Bradyrhizobium japonicum USDA110, and Bradyrhizobium elkanii USDA76 were determined towards their metal ion adsorption properties and possible modification of Cerrena unicolor laccase properties. The highest magnesium and iron ion-sorption capacity (~ 42 and ~ 14.5%, respectively) was observed for EPS isolated from B. japonicum USDA110. An evident influence of EPSs on the stability of laccase compared to the control values (without EPSs) was shown after 30-day incubation at 25 °C. The residual activity of laccases was obtained in the presence of Rh76EPS and Rh1021EPS, i.e., 49.5 and 41.5% of the initial catalytic activity, respectively. This result was confirmed by native PAGE electrophoresis. The EPS effect on laccase stability at different pH (from 3.8 to 7.0) was also estimated. The most significant changes at the optimum pH value (pH 5.8) was observed in samples of laccase stabilized by Rh76EPS and Rh1021EPS. Cyclic voltamperometry was used for analysis of electrochemical parameters of laccase stabilized by bacterial EPS and immobilized on single-walled carbon nanotubes (SWCNTs) with aryl residues. Laccases with Rh76EPS and Rh1021EPS had an evident shift of the value of the redox potential compared to the control without EPS addition. In conclusion, the results obtained in this work present a new potential use of bacterial EPSs as a metal-binding component and a modulator of laccase properties especially stability of enzyme activity, which can be a very effective tool in biotechnology and industrial applications.

  12. 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.

  13. 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.

  14. 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)

  15. Neoadjuvant chemotherapy for primary adenocarcinomas of the urinary bladder: a single-site experience.

    Science.gov (United States)

    Yu, Bin; Zhou, Jin; Cai, Hongzhou; Xu, Ting; Xu, Zicheng; Zou, Qing; Gu, Min

    2015-01-28

    Adenocarcinoma of the urinary bladder is a rare malignancy. Radical surgery is suggested as the best available treatment for early-stage disease, but there is currently no consensus on standard chemotherapy regimen for advanced stage. We assessed the feasibility and effect of neoadjuvant chemotherapy with gemcitabine and cisplatin (GC) plus S-1 for patients with locally advanced primary adenocarcinomas of the urinary bladder. Six patients with locally advanced urachal or non-urachal (n = 3, each) primary adenocarcinoma of the bladder were treated from October 2010 to October 2013 at a single center. All the patients were treated with 3 cycles (21d, each) of GC plus S-1 (gemcitabine, 1000 mg/m2, days 1 and 8; cisplatin, 70 mg/m2, day 2; and S-1, 50 mg bid, day 1-14). After neoadjuvant chemotherapy, patients with urachal cancer were treated with en bloc radical cystectomy and umbilectomy; the remaining 3 patients were treated with cystectomy. All patients successfully completed the neoadjuvant chemotherapy without serious side effects. Two patients were assessed as complete response, 2 as partial response, 1 as stable disease and 1 as progressive disease. Despite the limitations of a small study population, the GC plus S-1 regimen for locally advanced primary adenocarcinoma of the urinary bladder was effective, and facilitated the success of surgery to a certain extent. Short follow-up time was also a limitation of our study. More studies are needed to evaluate the results.

  16. Clinical characteristics and outcomes of placental site trophoblastic tumor: experience of single institution in Korea.

    Science.gov (United States)

    Lee, Hye-Joo; Shin, Wonkyo; Jang, Yun Jeong; Choi, Chel Hun; Lee, Jeong-Won; Bae, Duk-Soo; Kim, Byoung-Gie

    2018-05-01

    Placental site trophoblastic tumor (PSTT) is the rarest form of gestational trophoblastic disease (GTD) and the optimum management is still controversial. In this study, we analyzed the clinical features, treatment, and outcomes of 6 consecutive patients with PSTT treated in our institution. The electronic medical record database of Samsung Medical Center was screened to identify patients with PSTT from 1994 to 2017. Medical records for the details of each patient's clinical features and treatment were extracted and reviewed. This study was approved Institutional Review Board of our hospital. A total of 418 cases of GTD, 6 (1.4%) patients with PSTT were identified. The median age of the patients was 31 years. The antecedent pregnancy was term in all 5 cases with available antecedent pregnancy information and the median interval from pregnancy to diagnosis of PSTT was 8 months. The median titer of serum beta human chorionic gonadotropin (β-hCG) at diagnosis was 190.9 mIU/mL. Five (83.3%) patients presented with irregular vaginal bleeding and one (16.7%) had amenorrhea. All patients had disease confined to the uterus without metastasis at diagnosis and were successfully treated by hysterectomy alone. All of them were alive without disease during the follow-up period. In this study, we observed low level serum β-hCG titer and irregular vaginal bleeding with varying interval after antecedent term pregnancy were most common presenting features of PSTT. In addition, we demonstrated hysterectomy alone was successful for the treatment of stage I disease of PSTT.

  17. 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.

  18. 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

  19. 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.

  20. Site characterization and validation - equipment design and techniques used in single borehole hydraulic testing, simulated drift experiment and crosshole testing

    International Nuclear Information System (INIS)

    Holmes, D.C.; Sehlstedt, M.

    1991-10-01

    This report describes the equipment and techniques used to investigate the variation of hydrogeological parameters within a fractured crystalline rock mass. The testing program was performed during stage 3 of the site characterization and validation programme at the Stripa mine in Sweden. This programme used a multidisciplinary approach, combining geophysical, geological and hydrogeological methods, to determine how groundwater moved through the rock mass. The hydrogeological work package involved three components. Firstly, novel single borehole techniques (focused packer testing) were used to determine the distribution of hydraulic conductivity and head along individual boreholes. Secondly, water was abstracted from boreholes which were drilled to simulate a tunnel (simulated drift experiment). Locations and magnitudes of flows were measured together with pressure responses at various points in the SCV rock mass. Thirdly, small scale crosshole tests, involving detailed interference testing, were used to determine the variability of hydrogeological parameters within previously identified, significant flow zones. (au)

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. Structural Basis of Mec1-Ddc2-RPA Assembly and Activation on Single-Stranded DNA at Sites of Damage.

    Science.gov (United States)

    Deshpande, Ishan; Seeber, Andrew; Shimada, Kenji; Keusch, Jeremy J; Gut, Heinz; Gasser, Susan M

    2017-10-19

    Mec1-Ddc2 (ATR-ATRIP) is a key DNA-damage-sensing kinase that is recruited through the single-stranded (ss) DNA-binding replication protein A (RPA) to initiate the DNA damage checkpoint response. Activation of ATR-ATRIP in the absence of DNA damage is lethal. Therefore, it is important that damage-specific recruitment precedes kinase activation, which is achieved at least in part by Mec1-Ddc2 homodimerization. Here, we report a structural, biochemical, and functional characterization of the yeast Mec1-Ddc2-RPA assembly. High-resolution co-crystal structures of Ddc2-Rfa1 and Ddc2-Rfa1-t11 (K45E mutant) N termini and of the Ddc2 coiled-coil domain (CCD) provide insight into Mec1-Ddc2 homodimerization and damage-site targeting. Based on our structural and functional findings, we present a Mec1-Ddc2-RPA-ssDNA composite structural model. By way of validation, we show that RPA-dependent recruitment of Mec1-Ddc2 is crucial for maintaining its homodimeric state at ssDNA and that Ddc2's recruitment domain and CCD are important for Mec1-dependent survival of UV-light-induced DNA damage. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Seasonal variation of heavy metals in ambient air and precipitation at a single site in Washington, DC

    International Nuclear Information System (INIS)

    Melaku, Samuel; Morris, Vernon; Raghavan, Dharmaraj; Hosten, Charles

    2008-01-01

    Atmospheric samples of precipitation and ambient air were collected at a single site in Washington, DC, for 7 months (for ambient air samples) and 1 year (for wet deposition samples) and analyzed for arsenic, cadmium, chromium and lead. The ranges of heavy metal concentrations for 6-day wet deposition samples collected over the 1-year period were 0.20-1.3 μg/l, 0.060-5.1 μg/l, 0.062-4.6 μg/l and 0.11-3.2 μg/l for arsenic, cadmium, chromium and lead, respectively, with a precision better than 5% for more than 95% of the measurements. The ranges of heavy metal concentrations for the 6-day ambient air samples were 0.800-15.7 ng/m 3 , 1.50-30.0 ng/m 3 , 16.8-112 ng/m 3 , and 2.90-137 ng/m 3 for arsenic, cadmium, chromium and lead, respectively, with a precision better than 10%. The spread in the heavy metal concentration over the observation period suggests a high seasonal variability for heavy metal content in both ambient air and wet deposition samples. - High seasonal variability of heavy metals were observed in both ambient air and wet deposition samples

  10. Multicenter Experience with Nonischemic Multiport Laparoscopic and Laparoendoscopic Single-Site Partial Nephrectomy Utilizing Bipolar Radiofrequency Ablation Coagulator

    Directory of Open Access Journals (Sweden)

    Wassim M. Bazzi

    2011-01-01

    Full Text Available Objective. To investigate feasibility of multiport and laparoendoscopic single-site (LESS nonischemic laparoscopic partial nephrectomy (NI-LPN utilizing bipolar radiofrequency coagulator. Methods. Multicenter retrospective review of 60 patients (46 multiport/14 LESS undergoing NI-LPN between 4/2006 and 9/2009. Multiport and LESS NI-LPN utilized Habib 4X bipolar radiofrequency coagulator to form a hemostatic zone followed by nonischemic tumor excision and renorrhaphy. Demographics, tumor/perioperative characteristics, and outcomes were analyzed. Results. 59/60 (98.3% successfully underwent NI-LPN. Mean tumor size was 2.35 cm. Mean operative time was 160.0 minutes. Mean estimated blood loss was 131.4 mL. Preoperative/postoperative creatinine (mg/dL was 1.02/1.07 (=.471. All had negative margins. 12 (20% patients developed complications. 3 (5% developed urine leaks. No differences between multiport and LESS-PN were noted as regards demographics, tumor size, outcomes, and complications. Conclusion. Initial experience demonstrates that nonischemic multiport and LESS-PN is safe and efficacious, with excellent short-term preservation of renal function. Long-term data are needed to confirm oncological efficacy.

  11. 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.

  12. A comparison of single- and multi-site calibration and validation: a case study of SWAT in the Miyun Reservoir watershed, China

    Science.gov (United States)

    Bai, Jianwen; Shen, Zhenyao; Yan, Tiezhu

    2017-09-01

    An essential task in evaluating global water resource and pollution problems is to obtain the optimum set of parameters in hydrological models through calibration and validation. For a large-scale watershed, single-site calibration and validation may ignore spatial heterogeneity and may not meet the needs of the entire watershed. The goal of this study is to apply a multi-site calibration and validation of the Soil andWater Assessment Tool (SWAT), using the observed flow data at three monitoring sites within the Baihe watershed of the Miyun Reservoir watershed, China. Our results indicate that the multi-site calibration parameter values are more reasonable than those obtained from single-site calibrations. These results are mainly due to significant differences in the topographic factors over the large-scale area, human activities and climate variability. The multi-site method involves the division of the large watershed into smaller watersheds, and applying the calibrated parameters of the multi-site calibration to the entire watershed. It was anticipated that this case study could provide experience of multi-site calibration in a large-scale basin, and provide a good foundation for the simulation of other pollutants in followup work in the Miyun Reservoir watershed and other similar large areas.

  13. 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.

  14. pLoc-mAnimal: predict subcellular localization of animal proteins with both single and multiple sites.

    Science.gov (United States)

    Cheng, Xiang; Zhao, Shu-Guang; Lin, Wei-Zhong; Xiao, Xuan; Chou, Kuo-Chen

    2017-11-15

    Cells are deemed the basic unit of life. However, many important functions of cells as well as their growth and reproduction are performed via the protein molecules located at their different organelles or locations. Facing explosive growth of protein sequences, we are challenged to develop fast and effective method to annotate their subcellular localization. However, this is by no means an easy task. Particularly, mounting evidences have indicated proteins have multi-label feature meaning that they may simultaneously exist at, or move between, two or more different subcellular location sites. Unfortunately, most of the existing computational methods can only be used to deal with the single-label proteins. Although the 'iLoc-Animal' predictor developed recently is quite powerful that can be used to deal with the animal proteins with multiple locations as well, its prediction quality needs to be improved, particularly in enhancing the absolute true rate and reducing the absolute false rate. Here we propose a new predictor called 'pLoc-mAnimal', which is superior to iLoc-Animal as shown by the compelling facts. When tested by the most rigorous cross-validation on the same high-quality benchmark dataset, the absolute true success rate achieved by the new predictor is 37% higher and the absolute false rate is four times lower in comparison with the state-of-the-art predictor. To maximize the convenience of most experimental scientists, a user-friendly web-server for the new predictor has been established at http://www.jci-bioinfo.cn/pLoc-mAnimal/, by which users can easily get their desired results without the need to go through the complicated mathematics involved. xxiao@gordonlifescience.org or kcchou@gordonlifescience.org. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

  15. 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.

  16. Construction of Insulin 18-mer Nanoassemblies Driven by Coordination to Iron(II) and Zinc(II) Ions at Distinct Sites

    DEFF Research Database (Denmark)

    Munch, Henrik K.; Nygaard, Jesper; Christensen, Niels Johan

    2016-01-01

    Controlled self-assembly (SA) of proteins offers the possibility to tune their properties or to create new materials. Herein, we present the synthesis of a modified human insulin (HI) with two distinct metal-ion binding sites, one native, the other abiotic, enabling hierarchical SA through...

  17. 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

  18. 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...

  19. 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

  20. 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

  1. 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−.

  2. 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).

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

    KAUST Repository

    Shirbini, Afnan

    2017-01-01

    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

  4. 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.

  5. 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.

  6. 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.

  7. 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...

  8. Single-charge craters excavated during subsurface high-explosive experiments at Big Black Test Site, Mississippi

    International Nuclear Information System (INIS)

    Woodruff, W.R.; Bryan, J.B.

    1978-01-01

    Single-charge and row-charge subsurface cratering experiments were performed to learn how close-spacing enhances single-crater dimensions. Our first experimental phase established cratering curves for 60-lb charges of the chemical explosive. For the second phase, to be described in a subsequent report, the Row-cratering experiments were designed and executed. This data report contains excavated dimensions and auxiliary data for the single-charge cratering experiments. The dimensions for the row-charge experiments will be in the other report. Significant changes in the soil's water content appeared to cause a variability in the excavated dimensions. This variability clouded the interpretation and application of the cratering curves obtained

  9. Survey package: Technical and contracting strategies for single-shell tank waste retrieval on the Hanford Site

    International Nuclear Information System (INIS)

    Ramsower, D.C.

    1995-01-01

    Westinghouse Hanford Company is interested in innovative, commercially available or adaptable retrieval system equipment, concepts, and contracting strategies that will ad to existing Hanford Site technology and significantly reduce cost and/or risk from the baseline retrieval approach of sluicing (hydraulically mining) the waste from the SSTs onsite. The objective of this request is to gather information from industry to identify and summarize a suite of retrieval-related components, systems, and contracting approaches. This information will be used to ensure that WHC understands the various waste retrieval alternative approaches, their risks, and their application on the Hanford Site tanks for those occasions when sluicing is not sufficiently effective, appropriate, or cost-effective. An additional objective is to facilitate industry's understanding of the tank and site interface requirements for SST waste retrieval and the complex statutory, legal, regulatory, labor, and other institutional standards being applied to the Hanford Site. This effort will identify and summarize retrieval solutions by the end of September 1996 so that a clear basis for future retrieval program decisions can be established

  10. Photopicking : In Situ Approach for Site-Specific Attachment of Single Multiprotein Nanoparticles to Atomic Force Microscopy Tips

    NARCIS (Netherlands)

    Liashkovich, Ivan; Rosso, Gonzalo; Rangl, Martina; Ebner, Andreas; Hafezi, Wali; Kühn, Joachim; Schön, Peter; Hinterdorfer, Peter; Shahin, Victor

    2017-01-01

    Ligand–receptor interactions are fundamental in life sciences and include hormone–receptor, protein–protein, pathogen–host, and cell–cell interactions, among others. Atomic force microscopy (AFM) proved to be invaluable for scrutinizing ligand–receptor interactions at the single molecular level.

  11. Effect of connective tissue grafting on peri-implant tissue in single immediate implant sites : A RCT

    NARCIS (Netherlands)

    Zuiderveld, Elise G; Meijer, Henny J A; den Hartog, Laurens; Vissink, Arjan; Raghoebar, Gerry M

    AimTo assess the effect of connective tissue grafting on the mid-buccal mucosal level (MBML) of immediately placed and provisionalized single implants in the maxillofacial aesthetic zone. Materials and methodsSixty patients with a failing tooth were provided with an immediately placed and

  12. Pediatric Emergency Department Suicidal Patients: Two-Site Evaluation of Suicide Ideators, Single Attempters, and Repeat Attempters

    Science.gov (United States)

    Asarnow, Joan Rosenbaum; Baraff, Larry J.; Berk, Michele; Grob, Charles; Devich-Navarro, Mona; Suddath, Robert; Piacentini, John; Tang, Lingqi

    2008-01-01

    The study examines ideators, single attempters, and repeats attempters of suicide to clarify optimal strategies for emergency department management and risk assessment to help them in reducing youth suicide and suicide attempts. Depression was found to be a strong predictor of suicide/suicide attempts along with substance use, externalizing…

  13. 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

  14. Site Selection Strategy of Single-Frequency Tuned R-APF for Background Harmonic Voltage Damping in Power Systems

    DEFF Research Database (Denmark)

    Sun, Xiaofeng; Zeng, Jian; Chen, Zhe

    2013-01-01

    , and analyze the harmonic voltage propagation caused by the background harmonic voltage in power systems. Then, a new strategy is proposed for the site selection of resistive active power filter to damp the background harmonic voltage in power systems. Experiments have been performed to verify the theoretical......Series resonance between capacitance and line inductance may magnify background harmonic voltage and worsen the harmonic voltage distortion in power systems. To solve this problem, in this paper, the transmission line theory is used to set up the distributed parameter model of power system feeders...

  15. 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.

  16. 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.

  17. 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.

  18. Groundwater quality assessment plan for single-shell tank waste management Area U at the Hanford Site

    International Nuclear Information System (INIS)

    FN Hodges; CJ Chou

    2000-01-01

    Waste Management Area U (WMA U) includes the U Tank Farm, is currently regulated under RCRA interim-status regulations, and is scheduled for closure probably post-2030. Groundwater monitoring has been under an evaluation program that compared general contaminant indicator parameters from downgradient wells to background values established from upgradient wells. One of the indicator parameters, specific conductance, exceeded its background value in one downgradient well triggering a change from detection monitoring to a groundwater quality assessment program. The objective of the first phase of this assessment program is to determine whether the increased concentrations of nitrate and chromium in groundwater are from WMA U or from an upgradient source. Based on the results of the first determination, if WMA U is not the source of contamination, then the site will revert to detection monitoring. If WMA U is the source, then a second part of the groundwater quality assessment plan will be prepared to define the rate and extent of migration of contaminants in the groundwater and their concentrations

  19. A single acidic residue can guide binding site selection but does not govern QacR cationic-drug affinity.

    Directory of Open Access Journals (Sweden)

    Kate M Peters

    Full Text Available Structures of the multidrug-binding repressor protein QacR with monovalent and bivalent cationic drugs revealed that the carboxylate side-chains of E90 and E120 were proximal to the positively charged nitrogens of the ligands ethidium, malachite green and rhodamine 6G, and therefore may contribute to drug neutralization and binding affinity. Here, we report structural, biochemical and in vivo effects of substituting these glutamate residues. Unexpectedly, substitutions had little impact on ligand affinity or in vivo induction capabilities. Structures of QacR(E90Q and QacR(E120Q with ethidium or malachite green took similar global conformations that differed significantly from all previously described QacR-drug complexes but still prohibited binding to cognate DNA. Strikingly, the QacR(E90Q-rhodamine 6G complex revealed two mutually exclusive rhodamine 6G binding sites. Despite multiple structural changes, all drug binding was essentially isoenergetic. Thus, these data strongly suggest that rather than contributing significantly to ligand binding affinity, the role of acidic residues lining the QacR multidrug-binding pocket is primarily to attract and guide cationic drugs to the "best available" positions within the pocket that elicit QacR induction.

  20. Single-Tooth Morse Taper Connection Implant Placed in Grafted Site of the Anterior Maxilla: Clinical and Radiographic Evaluation

    Directory of Open Access Journals (Sweden)

    Francesco Guido Mangano

    2014-01-01

    Full Text Available The aim of this study was to achieve aesthetically pleasing soft tissue contours in a severely compromised tooth in the anterior region of the maxilla. For a right-maxillary central incisor with localized advanced chronic periodontitis a tooth extraction followed by reconstructive procedures and delayed implant placement was proposed and accepted by the patient. Guided bone regeneration (GBR technique was employed, with a biphasic calcium-phosphate (BCP block graft placed in the extraction socket in conjunction with granules of the same material and a resorbable barrier membrane. After 6 months of healing, an implant was installed. The acrylic provisional restoration remained in situ for 3 months and then was substituted with the definitive crown. This ridge reconstruction technique enabled preserving both hard and soft tissues and counteracting vertical and horizontal bone resorption after tooth extraction and allowed for an ideal three-dimensional implant placement. Localized severe alveolar bone resorption of the anterior maxilla associated with chronic periodontal disease can be successfully treated by means of ridge reconstruction with GBR and delayed implant insertion; the placement of an early-loaded, Morse taper connection implant in the grafted site was effective to create an excellent clinical aesthetic result and to maintain it along time.

  1. 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)

  2. 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.

  3. "In situ" observation of the role of chloride ion binding to monkey green sensitive visual pigment by ATR-FTIR spectroscopy.

    Science.gov (United States)

    Katayama, Kota; Furutani, Yuji; Iwaki, Masayo; Fukuda, Tetsuya; Imai, Hiroo; Kandori, Hideki

    2018-01-31

    Long-wavelength-sensitive (LWS) pigment possesses a chloride binding site in its protein moiety. The binding of chloride alters the absorption spectra of LWS; this is known as the chloride effect. Although the two amino acid substitutions of His197 and Lys200 influence the chloride effect, the molecular mechanism of chloride binding, which underlies the spectral tuning, has yet to be clarified. In this study, we applied ATR-FTIR spectroscopy to monkey green (MG) pigment to gain structural information of the chloride binding site. The results suggest that chloride binding stabilizes the β-sheet structure on the extracellular side loop with perturbation of the retinal polyene chain, promotes a hydrogen bonding exchange with the hydroxyl group of Tyr, and alters the protonation state of carboxylate. Combining with the results of the binding analyses of various anions (Br - , I - and NO 3 - ), our findings suggest that the anion binding pocket is organized for only Cl - (or Br - ) to stabilize conformation around the retinal chromophore, which is functionally relevant with absorbing long wavelength light.

  4. RCRA Assessment Plan for Single-Shell Tank Waste Management Area S-SX at the Hanford Site

    International Nuclear Information System (INIS)

    Chou, C.J.; Johnson, V.G.

    1999-01-01

    A groundwater quality assessment plan was prepared for waste management area S-SX at the Hanford Site. Groundwater monitoring is conducted at this facility in accordance with Title 40, Code of Federal Regulation (CFR) Part 265, Subpart F [and by reference of Washington Administrative Code (WAC) 173-303-400(3)]. The facility was placed in assessment groundwater monitoring program status after elevated waste constituents and indicator parameter measurements (i.e., chromium, technetium-99 and specific conductance) in downgradient monitoring wells were observed and confirmed. A first determination, as allowed under 40 CFR 265.93(d), provides the owner/operator of a facility an opportunity to demonstrate that the regulated unit is not the source of groundwater contamination. Based on results of the first determination it was concluded that multiple source locations in the waste management area could account for observed spatial and temporal groundwater contamination patterns. Consequently, a continued investigation is required. This plan, developed using the data quality objectives process, is intended to comply with the continued investigation requirement. Accordingly, the primary purpose of the present plan is to determine the rate and extent of dangerous waste (hexavalent chromium and nitrate) and radioactive constituents (e.g., technetium-99) in groundwater and to determine their concentrations in groundwater beneath waste management area S-SX. Comments and concerns expressed by the Washington State Department of Ecology on the initial waste management area S-SX assessment report were addressed in the descriptive narrative of this plan as well as in the planned activities. Comment disposition is documented in a separate addendum to this plan

  5. Silica-supported, single-site titanium catalysts for olefin epoxidation. A molecular precursor strategy for control of catalyst structure.

    Science.gov (United States)

    Jarupatrakorn, Jonggol; Don Tilley, T

    2002-07-17

    A molecular precursor approach involving simple grafting procedures was used to produce site-isolated titanium-supported epoxidation catalysts of high activity and selectivity. The tris(tert-butoxy)siloxy titanium complexes Ti[OSi(O(t)Bu)(3)](4) (TiSi4), ((i)PrO)Ti[OSi(O(t)Bu)(3)](3) (TiSi3), and ((t)BuO)(3)TiOSi(O(t)Bu)(3) (TiSi) react with the hydroxyl groups of amorphous Aerosil, mesoporous MCM-41, and SBA-15 via loss of HO(t)Bu and/or HOSi(O(t)Bu)(3) and introduction of titanium species onto the silica surface. Powder X-ray diffraction, nitrogen adsorption/desorption, infrared, and diffuse reflectance ultraviolet spectroscopies were used to investigate the structures and chemical natures of the surface-bound titanium species. The titanium species exist mainly in isolated, tetrahedral coordination environments. Increasing the number of siloxide ligands in the molecular precursor decreases the amount of titanium that can be introduced this way, but also enhances the catalytic activity and selectivity for the epoxidation of cyclohexene with cumene hydroperoxide as oxidant. In addition, the high surface area mesoporous silicas (MCM-41 and SBA-15) are more effective than amorphous silica as supports for these catalysts. Supporting TiSi3 on the SBA-15 affords highly active cyclohexene epoxidation catalysts (0.25-1.77 wt % Ti loading) that provide turnover frequencies (TOFs) of 500-1500 h(-1) after 1 h (TOFs are reduced by about half after calcination). These results demonstrate that oxygen-rich siloxide complexes of titanium are useful as precursors to supported epoxidation catalysts.

  6. Tuning of the Lethal Response to Multiple Stressors with a Single-Site Mutation during Clinical Infection by Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Krishan Kumar

    2017-10-01

    Full Text Available The agr system of Staphylococcus aureus promotes invasion of host tissues, and as expected, agents that block agr quorum sensing have anti-infective properties. Paradoxically, agr-defective mutants are frequently recovered from patients, especially those persistently infected with S. aureus. We found that an agr deficiency increased survival of cultured bacteria during severe stress, such as treatment with gentamicin, ciprofloxacin, heat, or low pH. With daptomycin, deletion of agr decreased survival. Therefore, agr activity can be either detrimental or protective, depending on the type of lethal stress. Deletion of agr had no effect on the ability of the antimicrobials to block bacterial growth, indicating that agr effects are limited to lethal action. Thus, the effect of an agr deletion is on bacterial tolerance, not resistance. For gentamicin and daptomycin, activity can be altered by agr-regulated secreted factors. For ciprofloxacin, a detrimental function was downregulation of glutathione peroxidase (bsaA, an enzyme responsible for defense against oxidative stress. Deficiencies in agr and bsaA were epistatic for survival, consistent with agr having a destructive role mediated by reactive oxygen species. Enhanced susceptibility to lethal stress by wild-type agr, particularly antimicrobial stress, helps explain why inactivating mutations in S. aureus agr commonly occur in hospitalized patients during infection. Moreover, the agr quorum-sensing system of S. aureus provides a clinically relevant example in which a single-step change in the response to severe stress alters the evolutionary path of a pathogen during infection.

  7. 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

  8. 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

  9. Role of four conserved aspartic acid residues of EF-loops in the metal ion binding and in the self-assembly of ciliate Euplotes octocarinatus centrin.

    Science.gov (United States)

    Liu, Wen; Duan, Lian; Sun, Tijian; Yang, Binsheng

    2016-12-01

    Ciliate Euplotes octocarinatus centrin (EoCen) is an EF-hand calcium-binding protein closely related to the prototypical calcium sensor protein calmodulin. Four mutants (D37K, D73K, D110K and D146K) were created firstly to elucidate the importance of the first aspartic acid residues (Asp37, Asp73, Asp110 and Asp146) in the beginning of the four EF-loops of EoCen. Aromatic-sensitized Tb 3+ fluorescence indicates that the aspartic acid residues are very important for the metal-binding of EoCen, except for Asp73 (in EF-loop II). Resonance light scattering (RLS) measurements for different metal ions (Ca 2+ and Tb 3+ ) binding proteins suggest that the order of four conserved aspartic acid residues for contributing to the self-assembly of EoCen is Asp37 > Asp146 > Asp110 > Asp73. Cross-linking experiment also exhibits that Asp37 and Asp146 play critical role in the self-assembly of EoCen. Asp37, in site I, which is located in the N-terminal domain, plays the most important role in the metal ion-dependent self-assembly of EoCen, and there is cooperativity between N-terminal and C-terminal domain (especially the site IV). In addition, the dependence of Tb 3+ induced self-assembly of EoCen and the mutants on various factors, including ionic strength and pH, were characterized using RLS. Finally, 2-p-toluidinylnaphthalene-6-sulfonate (TNS) binding, ionic strength and pH control experiments indicate that in the process of EoCen self-assembly, molecular interactions are mediated by both electrostatic and hydrophobic forces, and the hydrophobic interaction has the important status.

  10. A safety assessment of rotary mode core sampling in flammable gas single shell tanks: Hanford Site, Richland, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Raymond, R.E.

    1996-04-15

    This safety assessment (SA) addresses each of the required elements associated with the installation, operation, and removal of a rotary-mode core sampling (RMCS) device in flammable-gas single-shell tanks (SSTs). The RMCS operations are needed in order to retrieve waste samples from SSTs with hard layers of waste for which push-mode sampling is not adequate for sampling. In this SA, potential hazards associated with the proposed action were identified and evaluated systematically. Several potential accident cases that could result in radiological or toxicological gas releases were identified and analyzed and their consequences assessed. Administrative controls, procedures and design changes required to eliminate or reduce the potential of hazards were identified. The accidents were analyzed under nine categories, four of which were burn scenarios. In SSTS, burn accidents result in unacceptable consequences because of a potential dome collapse. The accidents in which an aboveground burn propagates into the dome space were shown to be in the ``beyond extremely unlikely`` frequency category. Given the unknown nature of the gas-release behavior in the SSTS, a number of design changes and administrative controls were implemented to achieve these low frequencies. Likewise, drill string fires and dome space fires were shown to be very low frequency accidents by taking credit for the design changes, controls, and available experimental and analytical data. However, a number of Bureau of Mines (BOM) tests must be completed before some of the burn accidents can be dismissed with high confidence. Under the category of waste fires, the possibility of igniting the entrapped gases and the waste itself were analyzed. Experiments are being conducted at the BOM to demonstrate that the drill bit is not capable of igniting the trapped gas in the waste. Laboratory testing and thermal analysis demonstrated that, under normal operating conditions, the drill bit will not create high

  11. A safety assessment of rotary mode core sampling in flammable gas single shell tanks: Hanford Site, Richland, Washington

    International Nuclear Information System (INIS)

    Raymond, R.E.

    1996-01-01

    This safety assessment (SA) addresses each of the required elements associated with the installation, operation, and removal of a rotary-mode core sampling (RMCS) device in flammable-gas single-shell tanks (SSTs). The RMCS operations are needed in order to retrieve waste samples from SSTs with hard layers of waste for which push-mode sampling is not adequate for sampling. In this SA, potential hazards associated with the proposed action were identified and evaluated systematically. Several potential accident cases that could result in radiological or toxicological gas releases were identified and analyzed and their consequences assessed. Administrative controls, procedures and design changes required to eliminate or reduce the potential of hazards were identified. The accidents were analyzed under nine categories, four of which were burn scenarios. In SSTS, burn accidents result in unacceptable consequences because of a potential dome collapse. The accidents in which an aboveground burn propagates into the dome space were shown to be in the ''beyond extremely unlikely'' frequency category. Given the unknown nature of the gas-release behavior in the SSTS, a number of design changes and administrative controls were implemented to achieve these low frequencies. Likewise, drill string fires and dome space fires were shown to be very low frequency accidents by taking credit for the design changes, controls, and available experimental and analytical data. However, a number of Bureau of Mines (BOM) tests must be completed before some of the burn accidents can be dismissed with high confidence. Under the category of waste fires, the possibility of igniting the entrapped gases and the waste itself were analyzed. Experiments are being conducted at the BOM to demonstrate that the drill bit is not capable of igniting the trapped gas in the waste. Laboratory testing and thermal analysis demonstrated that, under normal operating conditions, the drill bit will not create high

  12. 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

  13. HuR binds to a single site on the C/EBPβ mRNA of 3T3-L1 adipocytes

    International Nuclear Information System (INIS)

    Jones, Heath; Carver, Melinda; Pekala, Phillip H.

    2007-01-01

    HuR is a ligand for nuclear mRNAs containing adenylate-uridylate rich elements in the 3'-untranslated region. Once bound to the mRNA, HuR is recognized by adapter proteins which then facilitate nuclear export of the complex. In the cytosol HuR is thought to function to control stability and translation of its ligand message. In the 3T3-L1 cells HuR is constitutively expressed and localized predominantly to the nucleus in the preadipocytes. However within 30 min of exposure to the differentiation stimulus, the HuR content in the cytosol increases consistent with HuR regulating the availability of relevant mRNAs for translation. Using in vitro RNA gel shifts, we have demonstrated that the C/EBPβ message is a ligand for HuR and that the single binding site is an adenylate-uridylate rich element in the 3'-untranslated region

  14. Summary of air permeability data from single-hole injection tests in unsaturated fractured tuffs at the Apache Leap Research Site: Results of steady-state test interpretation

    International Nuclear Information System (INIS)

    Guzman, A.G.; Geddis, A.M.; Henrich, M.J.; Lohrstorfer, C.F.; Neuman, S.P.

    1996-03-01

    This document summarizes air permeability estimates obtained from single hole pneumatic injection tests in unsaturated fractured tuffs at the Covered Borehole Site (CBS) within the larger apache Leap Research Site (ALRS). Only permeability estimates obtained from a steady state interpretation of relatively stable pressure and flow rate data are included. Tests were conducted in five boreholes inclined at 45 degree to the horizontal, and one vertical borehole. Over 180 borehole segments were tested by setting the packers 1 m apart. Additional tests were conducted in segments of lengths 0.5, 2.0, and 3.0 m in one borehole, and 2.0 m in another borehole, bringing the total number of tests to over 270. Tests were conducted by maintaining a constant injection rate until air pressure became relatively stable and remained so for some time. The injection rate was then incremented by a constant value and the procedure repeated. The air injection rate, pressure, temperature, and relative humidity were recorded. For each relatively stable period of injection rate and pressure, air permeability was estimated by treating the rock around each test interval as a uniform, isotropic porous medium within which air flows as a single phase under steady state, in a pressure field exhibiting prolate spheroidal symmetry. For each permeability estimate the authors list the corresponding injection rate, pressure, temperature and relative humidity. They also present selected graphs which show how the latter quantities vary with time; logarithmic plots of pressure versus time which demonstrate the importance of borehole storage effects during the early transient portion of each incremental test period; and semilogarithmic plots of pressure versus recovery time at the end of each test sequence

  15. Laparoendoscopic single site (LESS) in vivo suturing using a magnetic anchoring and guidance system (MAGS) camera in a porcine model: impact on ergonomics and workload.

    Science.gov (United States)

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

    2013-01-01

    To compare the ergonomics and workload of the surgeon during single-site suturing while using the magnetic anchoring and guidance system (MAGS) camera vs a conventional laparoscope. Seven urologic surgeons were enrolled and divided into an expert group (n=2) and a novice group (n=5) according to their laparoendoscopic single-site (LESS) experience. Each surgeon performed 2 conventional LESS and 2 MAGS camera-assisted LESS vesicostomy closures in a porcine model. A Likert scale (scoring 1-5) questionnaire assessing workload, ergonomics, technical difficulty, visualization, and needle handling, as well as a validated National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire were used to evaluate the tasks and workloads. MAGS LESS suturing was universally favored by expert and novice surgeons compared with conventional LESS in workload (3.4 vs 4.2), ergonomics (3.4 vs 4.4), technical challenge (3.3 vs 4.3), visualization (2.4 vs 3.3), and needle handling (3.1 vs 3.9 respectively; PNASA-TLX assessments found MAGS LESS suturing significantly decreased the workload in physical demand (P=.004), temporal demand (P=.017), and effort (P=.006). External instrument clashing was significantly reduced in MAGS LESS suturing (P<.001). The total operative time of MAGS LESS suturing was comparable to that of conventional LESS (P=.89). MAGS camera technology significantly decreased surgeon workload and improved ergonomics. Nevertheless, LESS suturing and knot tying remains a challenging task that requires training, regardless of which camera is used. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. 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

  17. Alkylation of acetohydroxyacid synthase I from Escherichia coli K-12 by 3-bromopyruvate: evidence for a single active site catalyzing acetolactate and acetohydroxybutyrate synthesis.

    Science.gov (United States)

    Silverman, P M; Eoyang, L

    1987-01-01

    Acetohydroxyacid synthase I (AHAS I) purified from Escherichia coli K-12 was irreversibly inactivated by incubation with 3-bromopyruvate. Inactivation was specific, insofar as bromoacetate and iodoacetate were much less effective than bromopyruvate. Inactivation was accompanied by incorporation of radioactivity from 3-bromo[2-14C]pyruvate into acid-insoluble material. More than 95% of the incorporated radioactivity coelectrophoresed with the 60-kilodalton IlvB subunit of the enzyme through a sodium dodecyl sulfate-polyacrylamide gel; less than 5% coelectrophoresed with the 11.2-kilodalton IlvN subunit. The stoichiometry of incorporation at nearly complete inactivation was 1 mol of 14C per mol of IlvB polypeptide. These data indicate that bromopyruvate inactivates AHAS I by alkylating an amino acid at or near a single active site located in the IlvB subunit of the enzyme. We confirmed that this alkylation inactivated both AHAS reactions normally catalyzed by AHAS I. These results provide the first direct evidence that AHAS I catalyzes both acetohydroxybutyrate and acetolactate synthesis from the same active site. Images PMID:3294793

  18. Alkylation of acetohydroxyacid synthase I from Escherichia coli K-12 by 3-bromopyruvate: evidence for a single active site catalyzing acetolactate and acetohydroxybutyrate synthesis

    International Nuclear Information System (INIS)

    Silverman, P.M.; Eoyang, L.

    1987-01-01

    Acetohyroxyacid synthease I (AHAS I) purified from Escherichia coli K-12 was irreversibly inactivated by incubation with 3-bromopyruvate. Inactivation was specific, insofar as bromoacetate and iodoacetate were much less effective than bromopyruvate. Inactivation was accompanied by incorporation of radioactivity from 3-bromo[2- 14 C]pyruvate into acid-insoluble material. More than 95% of the incorporated radioactivity coelectrophoresed with the 60-kilodalton IlvB subunit of the enzyme through a sodium dodecyl sulfate-polyacrylamide gel; less than 5% coelectrophoresed with the 11.2-kilodalton IlvN subunit. The stoichiometry of incorporation at nearly complete inactivation was 1 mol of 14 C per mol of IlvB polypeptide. These data indicate that bromopyruvate inactivates AHAS I by alkylating an amino acid at or near a single active site located in the IlvB subunit of the enzyme. The authors confirmed that this alkylation inactivated both AHAS reactions normally catalyzed by AHAS I. These results provide the first direct evidence that AHAS I catalyzes both acetohydroxybutyrate and acetolactate synthesis from the same active site

  19. Identification of a common single nucleotide polymorphism at the primer binding site of D2S1360 that causes heterozygote peak imbalance when using the Investigator HDplex Kit.

    Science.gov (United States)

    Inokuchi, Shota; Yamashita, Yasuhiro; Nishimura, Kazuma; Nakanishi, Hiroaki; Saito, Kazuyuki

    2017-11-01

    Phenomena known as null alleles and peak imbalance can occur because of mutations in the primer binding sites used for DNA typing. In these cases, an accurate statistical evaluation of DNA typing is difficult. The estimated likelihood ratio is incorrectly calculated because of the null allele and allele dropout caused by mutation-induced peak imbalance. Although a number of studies have attempted to uncover examples of these phenomena, few reports are available on the human identification kit manufactured by Qiagen. In this study, 196 Japanese individuals who were heterozygous at D2S1360 were genotyped using an Investigator HDplex Kit with optimal amounts of DNA. A peak imbalance was frequently observed at the D2S1360 locus. We performed a sequencing analysis of the area surrounding the D2S1360 repeat motif to identify the cause for peak imbalance. A point mutation (G>A transition) 136 nucleotides upstream from the D2S1360 repeat motif was discovered in a number of samples. The allele frequency of the mutation was 0.0566 in the Japanese population. Therefore, human identification or kinship testing using the Investigator HDplex Kit requires caution because of the higher frequency of single nucleotide polymorphisms at the primer binding site of D2S1360 locus in the Japanese population.

  20. 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

  1. 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.

  2. Second site escape of a T20-dependent HIV-1 variant by a single amino acid change in the CD4 binding region of the envelope glycoprotein

    Directory of Open Access Journals (Sweden)

    Berkhout Ben

    2006-11-01

    Full Text Available Abstract Background We previously described the selection of a T20-dependent human immunodeficiency virus type-1 (HIV-1 variant in a patient on T20 therapy. The fusion inhibitor T20 targets the viral envelope (Env protein by blocking a conformational switch that is critical for viral entry into the host cell. T20-dependent viral entry is the result of 2 mutations in Env (GIA-SKY, creating a protein that undergoes a premature conformational switch, and the presence of T20 prevents this premature switch and rescues viral entry. In the present study, we performed 6 independent evolution experiments with the T20-dependent HIV-1 variant in the absence of T20, with the aim to identify second site compensatory changes, which may provide new mechanistic insights into Env function and the T20-dependence mechanism. Results Escape variants with improved replication capacity appeared within 42 days in 5 evolution cultures. Strikingly, 3 cultures revealed the same single amino acid change in the CD4 binding region of Env (glycine at position 431 substituted for arginine: G431R. This mutation was sufficient to abolish the T20-dependence phenotype and restore viral replication in the absence of T20. The GIA-SKY-G431R escape variant produces an Env protein that exhibits reduced syncytia formation and reduced cell-cell fusion activity. The escape variant was more sensitive to an antibody acting on an early gp41 intermediate, suggesting that the G431R mutation helps preserve a pre-fusion Env conformation, similar to T20 action. The escape variant was also less sensitive to soluble CD4, suggesting a reduced CD4 receptor affinity. Conclusion The forced evolution experiments indicate that the premature conformational switch of the T20-dependent HIV-1 Env variant (GIA-SKY can be corrected by a second site mutation in Env (GIA-SKY-G431R that affects the interaction with the CD4 receptor.

  3. Revisiting a many-body model for water based on a single polarizable site: from gas phase clusters to liquid and air/liquid water systems.

    Science.gov (United States)

    Réal, Florent; Vallet, Valérie; Flament, Jean-Pierre; Masella, Michel

    2013-09-21

    We present a revised version of the water many-body model TCPE [M. Masella and J.-P. Flament, J. Chem. Phys. 107, 9105 (1997)], which is based on a static three charge sites and a single polarizable site to model the molecular electrostatic properties of water, and on an anisotropic short range many-body energy term specially designed to accurately model hydrogen bonding in water. The parameters of the revised model, denoted TCPE/2013, are here developed to reproduce the ab initio energetic and geometrical properties of small water clusters (up to hexamers) and the repulsive water interactions occurring in cation first hydration shells. The model parameters have also been refined to reproduce two liquid water properties at ambient conditions, the density and the vaporization enthalpy. Thanks to its computational efficiency, the new model range of applicability was validated by performing simulations of liquid water over a wide range of temperatures and pressures, as well as by investigating water liquid/vapor interfaces over a large range of temperatures. It is shown to reproduce several important water properties at an accurate enough level of precision, such as the existence liquid water density maxima up to a pressure of 1000 atm, the water boiling temperature, the properties of the water critical point (temperature, pressure, and density), and the existence of a "singularity" temperature at about 225 K in the supercooled regime. This model appears thus to be particularly well-suited for characterizing ion hydration properties under different temperature and pressure conditions, as well as in different phases and interfaces.

  4. 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.

  5. Results of Phase I groundwater quality assessment for single-shell tank waste management Area S-SX at the Hanford Site

    International Nuclear Information System (INIS)

    Johnson, V.G.; Chou, C.J.

    1998-01-01

    Pacific Northwest National Laboratory (PNNL) conducted a Phase I, Resource Conservation and Recovery Act of 1976 (RCRA) groundwater quality assessment for the Richland Field Office of the U.S. Department of Energy (DOE-RL), in accordance with the Federal Facility Compliance Agreement. The purpose of the investigation was to determine if the Single-Shell Tank Waste Management Area (WMA) S-SX has impacted groundwater quality. The WMA is located in the southern portion of the 200 West Area of the Hanford Site and consists of the 241-S and 241-SX tank farms and ancillary waste systems. The unit is regulated under RCRA interim-status regulations (40 CFR 265, Subpart F) and was placed in assessment groundwater monitoring (40 CFR 265.93 [d]) in August 1996 because of elevated specific conductance and technetium-99, a non-RCRA co-contaminant, in downgradient monitoring wells. Major findings of the assessment are summarized below: (1) Distribution patterns for radionuclides and RCRA/dangerous waste constituents indicate WMA S-SX has contributed to groundwater contamination observed in downgradient monitoring wells. (2) Drinking water standards for nitrate and technetium-99 are currently exceeded in one RCRA-compliant well (299-W22-46) located at the southeastern comer of the SX tank farm. (3) Technetium-99, nitrate, and chromium concentrations in downgradient well 299-W22-46 (the well with the highest current concentrations) appear to be declining after reaching maximum concentrations in May 1997. (4) Cesium-137 and strontium-90, major constituents of concern in single-shell tank waste, were not detected in any of the RCRA-compliant wells in the WMA network, including the well with the highest current technetium-99 concentrations (299-W22-46). (5) Low but detectable strontium-90 and cesium-137 were found in one old well (2-W23-7), located inside and between the S and SX tank farms

  6. Cells deficient in PARP-1 show an accelerated accumulation of DNA single strand breaks, but not AP sites, over the PARP-1-proficient cells exposed to MMS

    Energy Technology Data Exchange (ETDEWEB)

    Pachkowski, Brian F. [Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC (United States); Tano, Keizo [Research Reactor Institute, Kyoto University, Kumatori (Japan); Afonin, Valeriy [Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC (United States); Elder, Rhoderick H. [School of Environment and Life Sciences, University of Salford, Greater Manchester (United Kingdom); Takeda, Shunichi [Department of Radiation Genetics, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto (Japan); Watanabe, Masami [Research Reactor Institute, Kyoto University, Kumatori (Japan); Swenberg, James A. [Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC (United States); Nakamura, Jun, E-mail: ynakamur@email.unc.edu [Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC (United States)

    2009-12-01

    Poly(ADP-ribose) polymerase-1 (PARP-1) is a base excision repair (BER) protein that binds to DNA single strand breaks (SSBs) and subsequently synthesizes and transfers poly(ADP-ribose) polymers to various nuclear proteins. Numerous biochemical studies have implicated PARP-1 as a modulator of BER; however, the role of PARP-1 in BER in living cells remains unclear partly due to lack of accurate quantitation of BER intermediates existing in cells. Since DT40 cells, chicken B lymphocytes, naturally lack PARP-2, DT40 cells allow for the investigation of the PARP-1 null phenotype without confounding by PARP-2. To test the hypothesis that PARP-1 is necessary for efficient BER during methylmethane sulfonate (MMS) exposure in vertebrate cells, intact DT40 cells and their isogenic PARP-1 null counterparts were challenged with different exposure scenarios for phenotypic characterization. With chronic exposure, PARP-1 null cells exhibited sensitivity to MMS but with an acute exposure did not accumulate base lesions or AP sites to a greater extent than wild-type cells. However, an increase in SSB content in PARP-1 null cell DNA, as indicated by glyoxal gel electrophoresis under neutral conditions, suggested the presence of BER intermediates. These data suggest that during exposure, PARP-1 impacts the stage of BER after excision of the deoxyribosephosphate moiety from the 5' end of DNA strand breaks by polymerase {beta}.

  7. 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

  8. Enhancement of Ag-Based Plasmonic Photocatalysis in Hydrogen Production from Ammonia Borane by the Assistance of Single-Site Ti-Oxide Moieties within a Silica Framework.

    Science.gov (United States)

    Verma, Priyanka; Kuwahara, Yasutaka; Mori, Kohsuke; Yamashita, Hiromi

    2017-03-13

    Ag nanoparticles (NPs) have gained great attention owing to their interesting plasmonic properties and efficient catalysis under visible-light irradiation. In this study, an Ag-based plasmonic catalyst supported on mesoporous silica with isolated and tetrahedrally coordinated single-site Ti-oxide moieties, namely, Ag/Ti-SBA-15, was designed with the purpose of utilizing the broad spectral range of solar energy. The Ti-SBA-15 support allows the deposition of small Ag NPs with a narrow size distribution. The chemical structure, morphology, and optical properties of the prepared catalyst were characterized by techniques such as UV/Vis, FT extended X-ray absorption fine structure, and X-ray photoelectron spectroscopy, field-emission SEM, TEM, and N 2 physisorption studies. The catalytic activity of Ag/Ti-SBA-15 in hydrogen production from ammonia borane by hydrolysis was significantly enhanced in comparison with Ag/SBA-15 without Ti-oxide moieties and Ag/TiO 2 /SBA-15 involving agglomerated TiO 2 , both in the dark and under light irradiation. Improved electron transfer under light irradiation caused by the creation of heterojunctions between Ag NPs and Ti-oxide moieties explains the results obtained in the present study. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Development of an in vivo visual robot system with a magnetic anchoring mechanism and a lens cleaning mechanism for laparoendoscopic single-site surgery (LESS).

    Science.gov (United States)

    Feng, Haibo; Dong, Dinghui; Ma, Tengfei; Zhuang, Jinlei; Fu, Yili; Lv, Yi; Li, Liyi

    2017-12-01

    Surgical robot systems which can significantly improve surgical procedures have been widely used in laparoendoscopic single-site surgery (LESS). For a relative complex surgical procedure, the development of an in vivo visual robot system for LESS can effectively improve the visualization for surgical robot systems. In this work, an in vivo visual robot system with a new mechanism for LESS was investigated. A finite element method (FEM) analysis was carried out to ensure the safety of the in vivo visual robot during the movement, which was the most important concern for surgical purposes. A master-slave control strategy was adopted, in which the control model was established by off-line experiments. The in vivo visual robot system was verified by using a phantom box. The experiment results show that the robot system can successfully realize the expected functionalities and meet the demands of LESS. The experiment results indicate that the in vivo visual robot with high manipulability has great potential in clinical application. Copyright © 2017 John Wiley & Sons, Ltd.

  10. 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.

  11. 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.

  12. Cells deficient in PARP-1 show an accelerated accumulation of DNA single strand breaks, but not AP sites, over the PARP-1-proficient cells exposed to MMS.

    Science.gov (United States)

    Pachkowski, Brian F; Tano, Keizo; Afonin, Valeriy; Elder, Rhoderick H; Takeda, Shunichi; Watanabe, Masami; Swenberg, James A; Nakamura, Jun

    2009-12-01

    Poly(ADP-ribose) polymerase-1 (PARP-1) is a base excision repair (BER) protein that binds to DNA single strand breaks (SSBs) and subsequently synthesizes and transfers poly(ADP-ribose) polymers to various nuclear proteins. Numerous biochemical studies have implicated PARP-1 as a modulator of BER; however, the role of PARP-1 in BER in living cells remains unclear partly due to lack of accurate quantitation of BER intermediates existing in cells. Since DT40 cells, chicken B lymphocytes, naturally lack PARP-2, DT40 cells allow for the investigation of the PARP-1 null phenotype without confounding by PARP-2. To test the hypothesis that PARP-1 is necessary for efficient BER during methylmethane sulfonate (MMS) exposure in vertebrate cells, intact DT40 cells and their isogenic PARP-1 null counterparts were challenged with different exposure scenarios for phenotypic characterization. With chronic exposure, PARP-1 null cells exhibited sensitivity to MMS but with an acute exposure did not accumulate base lesions or AP sites to a greater extent than wild-type cells. However, an increase in SSB content in PARP-1 null cell DNA, as indicated by glyoxal gel electrophoresis under neutral conditions, suggested the presence of BER intermediates. These data suggest that during exposure, PARP-1 impacts the stage of BER after excision of the deoxyribosephosphate moiety from the 5' end of DNA strand breaks by polymerase beta.

  13. Single- and Multi-Date Crop Identification Using PROBA-V 100 and 300 m S1 Products on Zlatia Test Site, Bulgaria

    Directory of Open Access Journals (Sweden)

    Eugenia Roumenina

    2015-10-01

    Full Text Available The monitoring of crops is of vital importance for food and environmental security in a global and European context. The main goal of this study was to assess the crop mapping performance provided by the 100 m spatial resolution of PROBA-V compared to coarser resolution data (e.g., PROBA-V at 300 m for a 2250 km2 test site in Bulgaria. The focus was on winter and summer crop mapping with three to five classes. For classification, single- and multi-date spectral data were used as well as NDVI time series. Our results demonstrate that crop identification using 100 m PROBA-V data performed significantly better in all experiments compared to the PROBA-V 300 m data. PROBA-V multispectral imagery, acquired in spring (March was the most appropriate for winter crop identification, while satellite data acquired in summer (July was superior for summer crop identification. The classification accuracy from PROBA-V 100 m compared to PROBA-V 300 m was improved by 5.8% to 14.8% depending on crop type. Stacked multi-date satellite images with three to four images gave overall classification accuracies of 74%–77% (PROBA-V 100 m data and 66%–70% (PROBA-V 300 m data with four classes (wheat, rapeseed, maize, and sunflower. This demonstrates that three to four image acquisitions, well distributed over the growing season, capture most of the spectral and temporal variability in our test site. Regarding the PROBA-V NDVI time series, useful results were only obtained if crops were grouped into two broader crop type classes (summer and winter crops. Mapping accuracies decreased significantly when mapping more classes. Again, a positive impact of the increased spatial resolution was noted. Together, the findings demonstrate the positive effect of the 100 m resolution PROBA-V data compared to the 300 m for crop mapping. This has important implications for future data provision and strengthens the arguments for a second generation of this mission originally designed

  14. Microsatellite and single nucleotide polymorphisms in the β-globin locus control region-hypersensitive Site 2: SPECIFICITY of Tunisian βs chromosomes.

    Science.gov (United States)

    Ben Mustapha, Maha; Moumni, Imen; Zorai, Amine; Douzi, Kaïs; Ghanem, Abderraouf; Abbes, Salem

    2012-01-01

    The diversity of sickle cell disease severity is attributed to several cis acting factors, among them the single nucleotide polymorphisms (SNPs) and (AT) rich region in the β-locus control region (β-LCR). This contains five DNase I hypersensitive sites (HS) located 6 to 22 kb upstream to the ϵ gene. The most important of these is the HS2 (5' β-LCR-HS2), characterized by the presence of three different SNPs and a microsatellite region known to be in association with β(S) chromosomes in various populations. The aim of this study was to present the molecular investigation of the 5' β-LCR-HS2 site in normal and sickle cell disease individuals in order to determine if there is any correlation or specificity between these molecular markers, the β(S) Tunisian chromosomes and phenotypical expression of sickle cell disease. One hundred and twenty-four chromosomes from Tunisian individuals (49 β(S) carriers and 13 normal individuals) were screened by polymerase chain reaction (PCR) and sequencing for the polymorphic short tandem microsatellite repeats (AT)(X)N(12)(AT)(Y) and the three SNPs (rs7119428, rs9736333 and rs60240093) of the 5' β-LCR-HS2. Twelve configurations of the microsatellite motif were found with an ancestral configuration elaborated by ClustalW software. Normal and mutated alleles were observed at the homozygous and heterozygous states for the three SNPs. Correlation between microsatellites and SNPs suggests that mutant SNP alleles were mainly associated, in the homozygous sickle cell disease phenotype, with the (AT)(8)N(12)GT(AT)(7) configuration, whereas, normal SNP alleles were associated with the (AT)(X)N(12)(AT)(11) configurations in normal β(A) chromosomes. The correlation of these various configurations with Hb F expression was also investigated. The principal component analysis (PCA) showed the correlation between the homozygous sickle cell disease phenotype, mutated SNP alleles and the Benin microsatellite configuration (AT)(8)N(12)GT

  15. 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.

  16. Laparo-Endoscopic Single-Site Surgery for Radical and Cytoreductive Nephrectomy, Renal Vein Thrombectomy, and Partial Nephrectomy: A Prospective Pilot Evaluation

    Directory of Open Access Journals (Sweden)

    Ithaar H. Derweesh

    2010-01-01

    Full Text Available Introduction. Laparo-endoscopic single-site surgery (LESS may diminish morbidity of laparoscopic surgery. We prospectively evaluated feasibility and outcomes of LESS-Radical Nephrectomy (LESS-RN and Partial Nephrectomy (LESS-PN. Methods. 10 patients underwent LESS-RN (6 and LESS-PN (4 between 2/2009-5/2009. LESS-RN included 2 with renal vein thrombectomy, one of which was also cytoreductive. Transperitoneal LESS access was obtained by periumbilical incision. Patient/tumor characteristics, oncologic, and quality of life (QoL outcomes were analyzed. Results. 3 Men/7 Women (mean age 58.7 years, median follow-up 9.8 months underwent LESS. 9/10 cases were completed successfully. All had negative margins. Mean operative time was 161 minutes, estimated blood loss was 125 mL, and incision size was 4.4 cm. Median tumor size for LESS-RN and -PN was 5.0 and 1.7 cm (=.045. Median LESS-PN ischemia time was 24 minutes; mean preoperative/postoperative creatinine were 0.7/0.8 mg/dL (=.19. Mean pain score at discharge was 1.3. Mean preoperative, 3-, and 6-month postoperative SF-36 QoL Score was 73.8, 74.4 and 77.1 (=.222. All patients are currently alive. Conclusions. LESS-RN, renal vein thrombectomy, and PN are technically feasible and safe while maintaining adherence to oncologic principles, with excellent QoL preservation and low discharge pain scores. Further study is requisite.

  17. 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.

  18. A Synthetic Single-Site Fe Nitrogenase: High Turnover, Freeze-Quench (57)Fe Mössbauer Data, and a Hydride Resting State.

    Science.gov (United States)

    Del Castillo, Trevor J; Thompson, Niklas B; Peters, Jonas C

    2016-04-27

    The mechanisms of the few known molecular nitrogen-fixing systems, including nitrogenase enzymes, are of much interest but are not fully understood. We recently reported that Fe-N2 complexes of tetradentate P3(E) ligands (E = B, C) generate catalytic yields of NH3 under an atmosphere of N2 with acid and reductant at low temperatures. Here we show that these Fe catalysts are unexpectedly robust and retain activity after multiple reloadings. Nearly an order of magnitude improvement in yield of NH3 for each Fe catalyst has been realized (up to 64 equiv of NH3 produced per Fe for P3(B) and up to 47 equiv for P3(C)) by increasing acid/reductant loading with highly purified acid. Cyclic voltammetry shows the apparent onset of catalysis at the P3(B)Fe-N2/P3(B)Fe-N2(-) couple and controlled-potential electrolysis of P3(B)Fe(+) at -45 °C demonstrates that electrolytic N2 reduction to NH3 is feasible. Kinetic studies reveal first-order rate dependence on Fe catalyst concentration (P3(B)), consistent with a single-site catalyst model. An isostructural system (P3(Si)) is shown to be appreciably more selective for hydrogen evolution. In situ freeze-quench Mössbauer spectroscopy during turnover reveals an iron-borohydrido-hydride complex as a likely resting state of the P3(B)Fe catalyst system. We postulate that hydrogen-evolving reaction activity may prevent iron hydride formation from poisoning the P3(B)Fe system. This idea may be important to consider in the design of synthetic nitrogenases and may also have broader significance given that intermediate metal hydrides and hydrogen evolution may play a key role in biological nitrogen fixation.

  19. Results of Phase I groundwater quality assessment for single-shell tank waste management areas T and TX-TY at the Hanford Site

    International Nuclear Information System (INIS)

    Hodges, F.N.

    1998-01-01

    Pacific Northwest National Laboratory (PNNL) conducted a Phase I, Resource Conservation and Recovery Act of 1976 (RCRA) groundwater quality assessment for the Richland Field Office of the U.S. Department of Energy (DOE-RL) under the requirements of the Federal Facility Compliance Agreement. The purpose of the investigation was to determine if the Single-Shell Tank Waste Management Areas (WMAs) T and TX-TY have impacted groundwater quality. Waste Management Areas T and TX-TY, located in the northern part of the 200 West Area of the Hanford Site, contain the 241-T, 241-TX, and 241-TY tank farms and ancillary waste systems. These two units are regulated under RCRA interim-status regulations (under 40 CFR 265.93) and were placed in assessment groundwater monitoring because of elevated specific conductance in downgradient wells. Anomalous concentrations of technetium-99, chromium, nitrate, iodine-129, and cobalt-60 also were observed in some downgradient wells. Phase I assessment, allowed under 40 CFR 265, provides the owner-operator of a facility with the opportunity to show that the observed contamination has a source other than the regulated unit. For this Phase I assessment, PNNL evaluated available information on groundwater chemistry and past waste management practices in the vicinity of WMAs T and TX-TY. Background contaminant concentrations in the vicinity of WMAs T and TX-TY are the result of several overlapping contaminant plumes resulting from past-practice waste disposal operations. This background has been used as baseline for determining potential WMA impacts on groundwater

  20. Revealing Ligand Binding Sites and Quantifying Subunit Variants of Noncovalent Protein Complexes in a Single Native Top-Down FTICR MS Experiment

    Science.gov (United States)

    Li, Huilin; Wongkongkathep, Piriya; Van Orden, Steve L.; Ogorzalek Loo, Rachel R.; Loo, Joseph A.

    2014-12-01

    "Native" mass spectrometry (MS) has been proven to be increasingly useful for structural biology studies of macromolecular assemblies. Using horse liver alcohol dehydrogenase (hADH) and yeast alcohol dehydrogenase (yADH) as examples, we demonstrate that rich information can be obtained in a single native top-down MS experiment using Fourier transform ion cyclotron mass spectrometry (FTICR MS). Beyond measuring the molecular weights of the protein complexes, isotopic mass resolution was achieved for yeast ADH tetramer (147 kDa) with an average resolving power of 412,700 at m/z 5466 in absorption mode, and the mass reflects that each subunit binds to two zinc atoms. The N-terminal 89 amino acid residues were sequenced in a top-down electron capture dissociation (ECD) experiment, along with the identifications of the zinc binding site at Cys46 and a point mutation (V58T). With the combination of various activation/dissociation techniques, including ECD, in-source dissociation (ISD), collisionally activated dissociation (CAD), and infrared multiphoton dissociation (IRMPD), 40% of the yADH sequence was derived directly from the native tetramer complex. For hADH, native top-down ECD-MS shows that both E and S subunits are present in the hADH sample, with a relative ratio of 4:1. Native top-down ISD of the hADH dimer shows that each subunit (E and S chains) binds not only to two zinc atoms, but also the NAD/NADH ligand, with a higher NAD/NADH binding preference for the S chain relative to the E chain. In total, 32% sequence coverage was achieved for both E and S chains.

  1. The Decline of Laparoendoscopic Single-Site Surgery: A Survey of the Endourological Society to Identify Shortcomings and Guidance for Future Directions.

    Science.gov (United States)

    Sorokin, Igor; Canvasser, Noah E; Irwin, Brian; Autorino, Riccardo; Liatsikos, Evangelos N; Cadeddu, Jeffrey A; Rane, Abhay

    2017-10-01

    To analyze the most recent temporal trends in the adoption of urologic laparoendoscopic single-site (LESS), to identify the perceived limitations associated with its decline, and to determine factors that might revive the role of LESS in the field of minimally invasive urologic surgery. A 15 question survey was created and sent to members of the Endourological Society in September 2016. Only members who performed LESS procedures in practice were asked to respond. In total, 106 urologists responded to the survey. Most of the respondents were from the United States (35%) and worked in an academic hospital (84.9%). Standard LESS was the most popular approach (78.1%), while 14.3% used robotics, and 7.6% used both. 2009 marked the most popular year to perform the initial (27.6%) and the majority (20%) of LESS procedures. The most common LESS procedure was a radical/simple nephrectomy (51%) followed by pyeloplasty (17.3%). In the past 12 months, 60% of respondents had performed no LESS procedures. Compared to conventional laparoscopy, respondents only believed cosmesis to be better, however, this enthusiasm waned over time. Worsening shifts in enthusiasm for LESS also occurred with patient desire, marketability, cost, safety, and robotic adaptability. The highest rated factor to help LESS regain popularity was a new robotic platform. The decline of LESS is apparent, with few urologists continuing to perform procedures attributed to multiple factors. The availability of a purpose-built robotic platform and better instrumentation might translate into a renewed future interest of LESS.

  2. Single thrombopoietin dose alleviates hematopoietic stem cells intrinsic short- and long-term ionizing radiation damage. In vivo identification of anatomical cell expansion sites.

    Science.gov (United States)

    Tronik-Le Roux, Diana; Nicola, Marie-Anne; Vaigot, Pierre; Nurden, Paquita

    2015-01-01

    Hematopoietic stem cells (HSC) are essential for maintaining the integrity of complex and long-lived organisms. HSC, which are self-renewing, reconstitute the hematopoietic system through out life and facilitate long-term repopulation of myeloablated recipients. We have previously demonstrated that when mice are exposed to sublethal doses of ionizing radiation, subsets of the stem/progenitor compartment are affected. In this study we examine the role of thrombopoietin (TPO) on the regenerative capacities of HSC after irradiation and report the first demonstration of efficacy of a single injection of TPO shortly after in vivo exposure to ionizing radiation for reducing HSC injury and improving their functional outcome. Our results demonstrate that TPO treatment not only reduced the number of apoptotic cells but also induced a significant modification of their intrinsic characteristics. These findings were supported by transplantation assays with long-term HSC that were irradiated or unirradiated, TPO treated or untreated, in CD45.1/CD45.2 systems and by using luciferase-labeled HSC for direct bioluminescence imaging in living animals. Of particular importance, our data demonstrate the skull to be a highly favorable site for the TPO-induced emergence of hematopoietic cells after irradiation, suggesting a TPO-mediated relationship of primitive hematopoietic cells to an anatomical component. Together, the data presented here: provide novel findings about aspects of TPO action on stem cells, open new areas of investigation for therapeutic options in patients who are treated with radiation therapy, and show that early administration of a clinically suitable TPO-agonist counteracts the previously observed adverse effects.

  3. Interpretation of Flow Logs from Nevada Test Site Boreholes to Estimate Hydraulic conductivity Using Numerical Simulations Constrained by Single-Well Aquifer Tests

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, C. Amanda; Halford, Keith J.; Laczniak, Randell J.

    2010-02-12

    Hydraulic conductivities of volcanic and carbonate lithologic units at the Nevada Test Site were estimated from flow logs and aquifer-test data. Borehole flow and drawdown were integrated and interpreted using a radial, axisymmetric flow model, AnalyzeHOLE. This integrated approach is used because complex well completions and heterogeneous aquifers and confining units produce vertical flow in the annular space and aquifers adjacent to the wellbore. AnalyzeHOLE simulates vertical flow, in addition to horizontal flow, which accounts for converging flow toward screen ends and diverging flow toward transmissive intervals. Simulated aquifers and confining units uniformly are subdivided by depth into intervals in which the hydraulic conductivity is estimated with the Parameter ESTimation (PEST) software. Between 50 and 150 hydraulic-conductivity parameters were estimated by minimizing weighted differences between simulated and measured flow and drawdown. Transmissivity estimates from single-well or multiple-well aquifer tests were used to constrain estimates of hydraulic conductivity. The distribution of hydraulic conductivity within each lithology had a minimum variance because estimates were constrained with Tikhonov regularization. AnalyzeHOLE simulated hydraulic-conductivity estimates for lithologic units across screened and cased intervals are as much as 100 times less than those estimated using proportional flow-log analyses applied across screened intervals only. Smaller estimates of hydraulic conductivity for individual lithologic units are simulated because sections of the unit behind cased intervals of the wellbore are not assumed to be impermeable, and therefore, can contribute flow to the wellbore. Simulated hydraulic-conductivity estimates vary by more than three orders of magnitude across a lithologic unit, indicating a high degree of heterogeneity in volcanic and carbonate-rock units. The higher water transmitting potential of carbonate-rock units relative

  4. An Initial Evaluation Of Characterization And Closure Options For Underground Pipelines Within A Hanford Site Single-Shell Tank Farm-13210

    International Nuclear Information System (INIS)

    Badden, Janet W.; Connelly, Michael P.; Seeley, Paul N.; Hendrickson, Michelle L.

    2013-01-01

    The Hanford Site includes 149 single-shell tanks, organized in 12 'tank farms,' with contents managed as high-level mixed waste. The Hanford Federal Facility Agreement and Consent Order requires that one tank farm, the Waste Management Area C, be closed by June 30, 2019. A challenge to this project is the disposition and closure of Waste Management Area C underground pipelines. Waste Management Area C contains nearly seven miles of pipelines and 200 separate pipe segments. The pipelines were taken out of service decades ago and contain unknown volumes and concentrations of tank waste residuals from past operations. To understand the scope of activities that may be required for these pipelines, an evaluation was performed. The purpose of the evaluation was to identify what, if any, characterization methods and/or closure actions may be implemented at Waste Management Area C for closure of Waste Management Area C by 2019. Physical and analytical data do not exist for Waste Management Area C pipeline waste residuals. To develop estimates of residual volumes and inventories of contamination, an extensive search of available information on pipelines was conducted. The search included evaluating historical operation and occurrence records, physical attributes, schematics and drawings, and contaminant inventories associated with the process history of plutonium separations facilities and waste separations and stabilization operations. Scoping analyses of impacts to human health and the environment using three separate methodologies were then developed based on the waste residual estimates. All analyses resulted in preliminary assessments, indicating that pipeline waste residuals presented a comparably low long-term impact to groundwater with respect to soil, tank and other ancillary equipment residuals, but exceeded Washington State cleanup requirement values. In addition to performing the impact analyses, the assessment evaluated available sampling technologies and

  5. Interpretation of Flow Logs from Nevada Test Site Boreholes to Estimate Hydraulic Conductivity Using Numerical Simulations Constrained by Single-Well Aquifer Tests

    Science.gov (United States)

    Garcia, C. Amanda; Halford, Keith J.; Laczniak, Randell J.

    2010-01-01

    Hydraulic conductivities of volcanic and carbonate lithologic units at the Nevada Test Site were estimated from flow logs and aquifer-test data. Borehole flow and drawdown were integrated and interpreted using a radial, axisymmetric flow model, AnalyzeHOLE. This integrated approach is used because complex well completions and heterogeneous aquifers and confining units produce vertical flow in the annular space and aquifers adjacent to the wellbore. AnalyzeHOLE simulates vertical flow, in addition to horizontal flow, which accounts for converging flow toward screen ends and diverging flow toward transmissive intervals. Simulated aquifers and confining units uniformly are subdivided by depth into intervals in which the hydraulic conductivity is estimated with the Parameter ESTimation (PEST) software. Between 50 and 150 hydraulic-conductivity parameters were estimated by minimizing weighted differences between simulated and measured flow and drawdown. Transmissivity estimates from single-well or multiple-well aquifer tests were used to constrain estimates of hydraulic conductivity. The distribution of hydraulic conductivity within each lithology had a minimum variance because estimates were constrained with Tikhonov regularization. AnalyzeHOLE simulated hydraulic-conductivity estimates for lithologic units across screened and cased intervals are as much as 100 times less than those estimated using proportional flow-log analyses applied across screened intervals only. Smaller estimates of hydraulic conductivity for individual lithologic units are simulated because sections of the unit behind cased intervals of the wellbore are not assumed to be impermeable, and therefore, can contribute flow to the wellbore. Simulated hydraulic-conductivity estimates vary by more than three orders of magnitude across a lithologic unit, indicating a high degree of heterogeneity in volcanic and carbonate-rock units. The higher water transmitting potential of carbonate-rock units relative

  6. An Initial Evaluation of Characterization and Closure Options for Underground Pipelines within a Hanford Site Single-Shell Tank Farm - 13210

    Energy Technology Data Exchange (ETDEWEB)

    Badden, Janet W.; Connelly, Michael P. [Washington River Protection Services, P.O. Box 850, Richland, Washington, 99352 (United States); Seeley, Paul N. [Cenibark International, Inc., 104318 Nicole Drive, Kennewick, Washington, 99338-7596 (United States); Hendrickson, Michelle L. [Washington State Department of Ecology, 3100 Port of Benton Blvd, Richland, Washington, 99354 (United States)

    2013-07-01

    The Hanford Site includes 149 single-shell tanks, organized in 12 'tank farms,' with contents managed as high-level mixed waste. The Hanford Federal Facility Agreement and Consent Order requires that one tank farm, the Waste Management Area C, be closed by June 30, 2019. A challenge to this project is the disposition and closure of Waste Management Area C underground pipelines. Waste Management Area C contains nearly seven miles of pipelines and 200 separate pipe segments. The pipelines were taken out of service decades ago and contain unknown volumes and concentrations of tank waste residuals from past operations. To understand the scope of activities that may be required for these pipelines, an evaluation was performed. The purpose of the evaluation was to identify what, if any, characterization methods and/or closure actions may be implemented at Waste Management Area C for closure of Waste Management Area C by 2019. Physical and analytical data do not exist for Waste Management Area C pipeline waste residuals. To develop estimates of residual volumes and inventories of contamination, an extensive search of available information on pipelines was conducted. The search included evaluating historical operation and occurrence records, physical attributes, schematics and drawings, and contaminant inventories associated with the process history of plutonium separations facilities and waste separations and stabilization operations. Scoping analyses of impacts to human health and the environment using three separate methodologies were then developed based on the waste residual estimates. All analyses resulted in preliminary assessments, indicating that pipeline waste residuals presented a comparably low long-term impact to groundwater with respect to soil, tank and other ancillary equipment residuals, but exceeded Washington State cleanup requirement values. In addition to performing the impact analyses, the assessment evaluated available sampling technologies

  7. 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

  8. Risk factors for surgical site infection following nonshunt pediatric neurosurgery: a review of 9296 procedures from a national database and comparison with a single-center experience.

    Science.gov (United States)

    Sherrod, Brandon A; Arynchyna, Anastasia A; Johnston, James M; Rozzelle, Curtis J; Blount, Jeffrey P; Oakes, W Jerry; Rocque, Brandon G

    2017-04-01

    OBJECTIVE Surgical site infection (SSI) following CSF shunt operations has been well studied, yet risk factors for nonshunt pediatric neurosurgery are less well understood. The purpose of this study was to determine SSI rates and risk factors following nonshunt pediatric neurosurgery using a nationwide patient cohort and an institutional data set specifically for better understanding SSI. METHODS The authors reviewed the American College of Surgeons National Surgical Quality Improvement Program-Pediatric (ACS NSQIP-P) database for the years 2012-2014, including all neurosurgical procedures performed on pediatric patients except CSF shunts and hematoma evacuations. SSI included deep (intracranial abscesses, meningitis, osteomyelitis, and ventriculitis) and superficial wound infections. The authors performed univariate analyses of SSI association with procedure, demographic, comorbidity, operative, and hospital variables, with subsequent multivariate logistic regression analysis to determine independent risk factors for SSI within 30 days of the index procedure. A similar analysis was performed using a detailed institutional infection database from Children's of Alabama (COA). RESULTS A total of 9296 nonshunt procedures were identified in NSQIP-P with an overall 30-day SSI rate of 2.7%. The 30-day SSI rate in the COA institutional database was similar (3.3% of 1103 procedures, p = 0.325). Postoperative time to SSI in NSQIP-P and COA was 14.6 ± 6.8 days and 14.8 ± 7.3 days, respectively (mean ± SD). Myelomeningocele (4.3% in NSQIP-P, 6.3% in COA), spine (3.5%, 4.9%), and epilepsy (3.4%, 3.1%) procedure categories had the highest SSI rates by procedure category in both NSQIP-P and COA. Independent SSI risk factors in NSQIP-P included postoperative pneumonia (OR 4.761, 95% CI 1.269-17.857, p = 0.021), immune disease/immunosuppressant use (OR 3.671, 95% CI 1.371-9.827, p = 0.010), cerebral palsy (OR 2.835, 95% CI 1.463-5.494, p = 0.002), emergency operation (OR 1

  9. Risk factors for surgical site infection following nonshunt pediatric neurosurgery: a review of 9296 procedures from a national database and comparison with a single-center experience

    Science.gov (United States)

    Sherrod, Brandon A.; Arynchyna, Anastasia A.; Johnston, James M.; Rozzelle, Curtis J.; Blount, Jeffrey P.; Oakes, W. Jerry; Rocque, Brandon G.

    2017-01-01

    Objective Surgical site infection (SSI) following CSF shunt operations has been well studied, yet risk factors for nonshunt pediatric neurosurgery are less well understood. The purpose of this study was to determine SSI rates and risk factors following nonshunt pediatric neurosurgery using a nationwide patient cohort and an institutional dataset specifically for better understanding SSI. Methods The authors reviewed the American College of Surgeons National Surgical Quality Improvement Program Pediatric (ACS NSQIP-P) database for the years 2012–2014, including all neurosurgical procedures performed on pediatric patients except CSF shunts and hematoma evacuations. SSI included deep (intracranial abscesses, meningitis, osteomyelitis, and ventriculitis) and superficial wound infections. The authors performed univariate analyses of SSI association with procedure, demographic, comorbidity, operative, and hospital variables, with subsequent multivariate logistic regression analysis to determine independent risk factors for SSI within 30 days of the index procedure. A similar analysis was performed using a detailed institutional infection database from Children’s Hospital of Alabama (COA). Results A total of 9296 nonshunt procedures were identified in NSQIP-P with an overall 30-day SSI rate of 2.7%. The 30-day SSI rate in the COA institutional database was similar (3.3% of 1103 procedures, p = 0.325). Postoperative time to SSI in NSQIP-P and COA was 14.6 ± 6.8 days and 14.8 ± 7.3 days, respectively (mean ± SD). Myelomeningocele (4.3% in NSQIP-P, 6.3% in COA), spine (3.5%, 4.9%), and epilepsy (3.4%, 3.1%) procedure categoriess had the highest SSI rates by procedure category in both NSQIP-P and COA. Independent SSI risk factors in NSQIP-P included postoperative pneumonia (OR 4.761, 95% CI 1.269–17.857, p = 0.021), immune disease/immunosuppressant use (OR 3.671, 95% CI 1.371–9.827, p = 0.010), cerebral palsy (OR 2.835, 95% CI 1.463–5.494, p = 0.002), emergency

  10. 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.

  11. A single mutation in the hepta-peptide active site of Aspergillus niger PhyA phytase leads to myriad of biochemical changes

    Science.gov (United States)

    The active site motif of proteins belonging to ‘Histidine Acid Phosphatase’ (HAP) contains a hepta-peptide region, RHGXRXP. A close comparison among fungal and yeast HAPs has revealed the fourth residue of the hepta-peptide to be E instead of A, which is the case with A. niger phyA phytase. However,...

  12. Coordination geometries of Zn(II) and Cd(II) in phosphotriesterase: Influence of water molecules in the active site

    DEFF Research Database (Denmark)

    Krauss, M; Olsen, Lars; Antony, J

    2002-01-01

    Models of the metal ion binding sites of native ZnZn and of cadmium-substituted ZnCd and CdCd phosphotriesterase, including full amino acid side chains, were geometry optimized with quantum mechanical methods, with effective fragment potentials (EFP) representing the protein environment surroundi...... to the Od1 of the carboxylate of the first-shell aspartate designated M 1, but the energy difference between Cd1Zn2 and the lowest energy Zn1Cd2 structure is only about 2 kcal/mol and decreasing with the addition of water molecules. The Zn1Cd2 arrangement is found experimentally....

  13. A surface structural model for ferrihydrite I: Sites related to primary charge, molar mass, and mass density

    Science.gov (United States)

    Hiemstra, Tjisse; Van Riemsdijk, Willem H.

    2009-08-01

    A multisite surface complexation (MUSIC) model for ferrihydrite (Fh) has been developed. The surface structure and composition of Fh nanoparticles are described in relation to ion binding and surface charge development. The site densities of the various reactive surface groups, the molar mass, the mass density, the specific surface area, and the particle size are quantified. As derived theoretically, molecular mass and mass density of nanoparticles will depend on the types of surface groups and the corresponding site densities and will vary with particle size and surface area because of a relatively large contribution of the surface groups in comparison to the mineral core of nanoparticles. The nano-sized (˜2.6 nm) particles of freshly prepared 2-line Fh as a whole have an increased molar mass of M ˜ 101 ± 2 g/mol Fe, a reduced mass density of ˜3.5 ± 0.1 g/cm 3, both relatively to the mineral core. The specific surface area is ˜650 m 2/g. Six-line Fh (5-6 nm) has a molar mass of M ˜ 94 ± 2 g/mol, a mass density of ˜3.9 ± 0.1 g/cm 3, and a surface area of ˜280 ± 30 m 2/g. Data analysis shows that the mineral core of Fh has an average chemical composition very close to FeOOH with M ˜ 89 g/mol. The mineral core has a mass density around ˜4.15 ± 0.1 g/cm 3, which is between that of feroxyhyte, goethite, and lepidocrocite. These results can be used to constrain structural models for Fh. Singly-coordinated surface groups dominate the surface of ferrihydrite (˜6.0 ± 0.5 nm -2). These groups can be present in two structural configurations. In pairs, the groups either form the edge of a single Fe-octahedron (˜2.5 nm -2) or are present at a single corner (˜3.5 nm -2) of two adjacent Fe octahedra. These configurations can form bidentate surface complexes by edge- and double-corner sharing, respectively, and may therefore respond differently to the binding of ions such as uranyl, carbonate, arsenite, phosphate, and others. The relatively low PZC of

  14. Evaluation of SAR procedures for D-e determination using single aliquots of quartz from two archaeological sites in South Africa

    CSIR Research Space (South Africa)

    Jacobs, Z

    2006-05-01

    Full Text Available stimulation between cycles in the SAR procedure were measured for dose recovery tests. The effects of these changes on measurement of D-e values for single aliquots of these two samples are reported. Both modifications improved D-e recovery, and the study...

  15. Genome sequences of thirty Escherichia coli O157:H7 isolates recovered from a single dairy farm and its associated off-site heifer raising facility

    Science.gov (United States)

    Cattle are the primary reservoir of Escherichia coli O157:H7, the most frequently isolated serotype of enterohemorrhagic E. coli infections among humans in North America. To evaluate the diversity of E. coli O157:H7 isolates within a single dairy herd the genomes of 30 isolates collected over a 7-ye...

  16. Virus-Clip: a fast and memory-efficient viral integration site detection tool at single-base resolution with annotation capability.

    Science.gov (United States)

    Ho, Daniel W H; Sze, Karen M F; Ng, Irene O L

    2015-08-28

    Viral integration into the human genome upon infection is an important risk factor for various human malignancies. We developed viral integration site detection tool called Virus-Clip, which makes use of information extracted from soft-clipped sequencing reads to identify exact positions of human and virus breakpoints of integration events. With initial read alignment to virus reference genome and streamlined procedures, Virus-Clip delivers a simple, fast and memory-efficient solution to viral integration site detection. Moreover, it can also automatically annotate the integration events with the corresponding affected human genes. Virus-Clip has been verified using whole-transcriptome sequencing data and its detection was validated to have satisfactory sensitivity and specificity. Marked advancement in performance was detected, compared to existing tools. It is applicable to versatile types of data including whole-genome sequencing, whole-transcriptome sequencing, and targeted sequencing. Virus-Clip is available at http://web.hku.hk/~dwhho/Virus-Clip.zip.

  17. Imbalanced multi-modal multi-label learning for subcellular localization prediction of human proteins with both single and multiple sites.

    Directory of Open Access Journals (Sweden)

    Jianjun He

    Full Text Available It is well known that an important step toward understanding the functions of a protein is to determine its subcellular location. Although numerous prediction algorithms have been developed, most of them typically focused on the proteins with only one location. In recent years, researchers have begun to pay attention to the subcellular localization prediction of the proteins with multiple sites. However, almost all the existing approaches have failed to take into account the correlations among the locations caused by the proteins with multiple sites, which may be the important information for improving the prediction accuracy of the proteins with multiple sites. In this paper, a new algorithm which can effectively exploit the correlations among the locations is proposed by using gaussian process model. Besides, the algorithm also can realize optimal linear combination of various feature extraction technologies and could be robust to the imbalanced data set. Experimental results on a human protein data set show that the proposed algorithm is valid and can achieve better performance than the existing approaches.

  18. Results of phase 1 groundwater quality assessment for Single-Shell Tank Waste Management Areas B-BX-BY at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Narbutovskih, S.M.

    1998-02-01

    Pacific Northwest National Laboratory conducted a Phase 1 (or first determination) groundwater quality assessment for the US Department of Energy, Richland Operations Office, in accordance with the Federal Facility Compliance Agreement. The purpose of the assessment was to determine if the Single-Shell Tank Waste Management Area (WMA) B-BX-BY has impacted groundwater quality. This report will document the evidence demonstrating that the WMA has impacted groundwater quality.

  19. Results of phase 1 groundwater quality assessment for Single-Shell Tank Waste Management Areas B-BX-BY at the Hanford Site

    International Nuclear Information System (INIS)

    Narbutovskih, S.M.

    1998-02-01

    Pacific Northwest National Laboratory conducted a Phase 1 (or first determination) groundwater quality assessment for the US Department of Energy, Richland Operations Office, in accordance with the Federal Facility Compliance Agreement. The purpose of the assessment was to determine if the Single-Shell Tank Waste Management Area (WMA) B-BX-BY has impacted groundwater quality. This report will document the evidence demonstrating that the WMA has impacted groundwater quality

  20. 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.

  1. Changes in implant stability using different site preparation techniques: twist drills versus piezosurgery. A single-blinded, randomized, controlled clinical trial.

    Science.gov (United States)

    Stacchi, Claudio; Vercellotti, Tomaso; Torelli, Lucio; Furlan, Fabio; Di Lenarda, Roberto

    2013-04-01

    The objective of the present investigation was to longitudinally monitor stability changes of implants inserted using traditional rotary instruments or piezoelectric inserts, and to follow their variations during the first 90 days of healing. A randomized, controlled trial was conducted on 20 patients. Each patient received two identical, adjacent implants in the upper premolar area: the test site was prepared with piezosurgery, and the control site was prepared using twist drills. Resonance frequency analysis measurements were taken by a blinded operator on the day of surgery and after 7, 14, 21, 28, 42, 56, and 90 days. At 90 days, 39 out of 40 implants were osseointegrated (one failure in the control group). Both groups showed an initial decrease in mean implant stability quotient (ISQ) values: a shift in implant stability to increasing ISQ values occurred after 14 days in the test group and after 21 days in the control group. The lowest mean ISQ value was recorded at 14 days for test implants (97.3% of the primary stability) and at 21 days for the control implants (90.8% of the primary stability). ISQ variations with respect to primary stability differed significantly between the two groups during the entire period of observation: from day 14 to day 42, in particular, the differences were extremely significant (p < .0001). All 39 implants were in function successfully at the visit scheduled 1 year after insertion. The findings from this study suggest that ultrasonic implant site preparation results in a limited decrease of ISQ values and in an earlier shifting from a decreasing to an increasing stability pattern, when compared with the traditional drilling technique. From a clinical point of view, implants inserted with the piezoelectric technique demonstrated a short-term clinical success similar to those inserted using twist drills. © 2011 Wiley Periodicals, Inc.

  2. A single site for N-linked glycosylation in the envelope glycoprotein of feline immunodeficiency virus modulates the virus-receptor interaction

    Directory of Open Access Journals (Sweden)

    Samman Ayman

    2008-08-01

    Full Text Available Abstract Feline immunodeficiency virus (FIV targets helper T cells by attachment of the envelope glycoprotein (Env to CD134, a subsequent interaction with CXCR4 then facilitating the process of viral entry. As the CXCR4 binding site is not exposed until CD134-binding has occurred then the virus is protected from neutralising antibodies targeting the CXCR4-binding site on Env. Prototypic FIV vaccines based on the FL4 strain of FIV contain a cell culture-adapted strain of FIV Petaluma, a CD134-independent strain of FIV that interacts directly with CXCR4. In addition to a characteristic increase in charge in the V3 loop homologue of FIVFL4, we identified two mutations in potential sites for N-linked glycosylation in the region of FIV Env analogous to the V1–V2 region of HIV and SIV Env, T271I and N342Y. When these mutations were introduced into the primary GL8 and CPG41 strains of FIV, the T271I mutation was found to alter the nature of the virus-CD134 interaction; primary viruses carrying the T271I mutation no longer required determinants in cysteine-rich domain (CRD 2 of CD134 for viral entry. The T271I mutation did not confer CD134-independent infection upon GL8 or CPG41, nor did it increase the affinity of the CXCR4 interaction, suggesting that the principal effect was targeted at reducing the complexity of the Env-CD134 interaction.

  3. Residues at a Single Site Differentiate Animal Cryptochromes from Cyclobutane Pyrimidine Dimer Photolyases by Affecting the Proteins' Preferences for Reduced FAD.

    Science.gov (United States)

    Xu, Lei; Wen, Bin; Wang, Yuan; Tian, Changqing; Wu, Mingcai; Zhu, Guoping

    2017-06-19

    Cryptochromes (CRYs) and photolyases belong to the cryptochrome/photolyase family (CPF). Reduced FAD is essential for photolyases to photorepair UV-induced cyclobutane pyrimidine dimers (CPDs) or 6-4 photoproducts in DNA. In Drosophila CRY (dCRY, a type I animal CRY), FAD is converted to the anionic radical but not to the reduced state upon illumination, which might induce a conformational change in the protein to relay the light signal downstream. To explore the foundation of these differences, multiple sequence alignment of 650 CPF protein sequences was performed. We identified a site facing FAD (Ala377 in Escherichia coli CPD photolyase and Val415 in dCRY), hereafter referred to as "site 377", that was distinctly conserved across these sequences: CPD photolyases often had Ala, Ser, or Asn at this site, whereas animal CRYs had Ile, Leu, or Val. The binding affinity for reduced FAD, but not the photorepair activity of E. coli photolyase, was dramatically impaired when replacing Ala377 with any of the three CRY residues. Conversely, in V415S and V415N mutants of dCRY, FAD was photoreduced to its fully reduced state after prolonged illumination, and light-dependent conformational changes of these mutants were severely inhibited. We speculate that the residues at site 377 play a key role in the different preferences of CPF proteins for reduced FAD, which differentiate animal CRYs from CPD photolyases. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Installation of a Hydrologic Characterization Network for Vadose Zone Monitoring of a Single-Shell Tank Farm at the U. S. Department of Energy Hanford Site

    International Nuclear Information System (INIS)

    Gee, Glendon W.; Ward, Anderson L.; Ritter, Jason C.; Sisson, James B.; Hubbell, Joel M.; Sydnor, Harold A.

    2001-01-01

    The Pacific Northwest National Laboratory, in collaboration with the Idaho National Engineering and Environmental Laboratory and Duratek Federal Services, deployed a suite of vadose-zone instruments at the B Tank Farm in the 200 E Area of the Hanford Site, near Richland, Washington, during the last quarter of FY 2001. The purpose of the deployment was to obtain in situ hydrologic characterization data within the vadose zone of a high-level-waste tank farm. Eight sensor nests, ranging in depth from 67 m (220 ft) below ground surface (bgs) to 0.9 m (3 ft) bgs were placed in contact with vadose-zone sediments inside a recently drilled, uncased, borehole (C3360) located adjacent to Tank B-110. The sensor sets are part of the Vadose Zone Monitoring System and include advanced tensiometers, heat dissipation units, frequency domain reflectometers, thermal probes, and vadose zone solution samplers. Within the top meter of the surface, a water flux meter was deployed to estimate net infiltration from meteoric water (rain and snowmelt) sources. In addition, a rain gage was located within the tank farm to document on-site precipitation events. All sensor units, with the exception of the solution samplers, were connected to a solar-powered data logger located within the tank farm. Data collected from these sensors are currently being accessed by modem and cell phone and will be analyzed as part of the DOE RL31SS31 project during the coming year (FY 2001)

  5. 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.

  6. Complicated Fermi-type vibronic resonance: Untangling of the single-site quasi-line fluorescence excitation spectra of a methylated dibenzoporphin

    International Nuclear Information System (INIS)

    Arabei, S.M.; Kuzmitsky, V.A.; Solovyov, K.N.

    2008-01-01

    The quasi-line low-temperature (4.2 K) fluorescence excitation spectra of 2,3,12,13-tetramethyldibenzo[g,q]porphin introduced into an n-octane matrix have been measured in the range of the S 2 0 electronic transition at selective fluorescence monitoring for the two main types of impurity centers (sites). A characteristic feature of these spectra is that a conglomerate of quasi-lines - a structured complex band - is observed instead of one 0-0 quasi-line of the S 2 0 transition. In this band, the intensity distributions for the two main sites considerably differ from each other. The occurrence of such conglomerates is interpreted as a result of nonadiabatic vibrational-electronic interaction between the vibronic S 2 and S 1 states (the complex vibronic analogue of the Fermi resonance). The frequencies and intensities of individual transitions determined from the deconvolution of complex conglomerates are used as the initial data for solving the inverse spectroscopic problem: the determination of the unperturbed electronic and vibrational levels of states involved in the resonance and the vibronic-interaction matrix elements between them. This problem is solved with a method developed previously. The experimental results and their analysis are compared to the analogous data obtained earlier for meso-tetraazaporphin and meso-tetrapropylporphin. The energy intervals between the S 2 and S 1 electronic levels (ΔE S 2 S 1 ) of the two main types of impurity centers formed by molecules of a given porphyrin in the crystal matrix are found to significantly differ from each other, the values of this difference (δΔE S 2 S 1 ) being considerably greater for tetramethyldibenzoporphin, δΔE S 2 S 1 =228cm -1 , than for the two other porphyrins. At the same time, the energies of the unperturbed vibrational states of the S 1 electronic level participating in the resonance are very close to each other for these two sites

  7. Site-Specific Growth and in Situ Integration of Different Nanowire Material Networks on a Single Chip: Toward a Nanowire-Based Electronic Nose for Gas Detection.

    Science.gov (United States)

    Hrachowina, Lukas; Domènech-Gil, Guillem; Pardo, Antonio; Seifner, Michael S; Gràcia, Isabel; Cané, Carles; Romano-Rodríguez, Albert; Barth, Sven

    2018-03-23

    A new method for the site-selective synthesis of nanowires has been developed to enable material growth with defined morphology and, at the same time, different composition on the same chip surface. The chemical vapor deposition approach for the growth of these nanowire-based resistive devices using micromembranes can be easily modified and represents a simple, adjustable fabrication process for the direct integration of nanowire meshes in multifunctional devices. This proof-of-concept study includes the deposition of SnO 2 , WO 3 , and Ge nanowires on the same chip. The individual resistors exhibit adequate gas sensing responses toward changing gas concentrations of CO, NO 2 , and humidity diluted in synthetic air. The data have been processed by principal component analysis with cluster responses that can be easily separated, and thus, the devices described herein are in principle suitable for environmental monitoring.

  8. First characterization and comparison of TEB model simulations with in situ measurements regarding radiation balance in a single urban canyon at the BOKU site (Vienna)

    Science.gov (United States)

    Oswald, Sandro; Trimmel, Heidelinde; Revesz, Michael; Nadeem, Imran; Masson, Valéry; Weihs, Philipp

    2017-04-01

    According to the World Health Organization more than half of the world population lives in a city since 2010. Predictions foresee that by 2030 six out of ten people will live in an urban area. As a result, many cities are expanding in size. Almost 10% of all urban dwellers live in megacities (defined according to UN HABITAT as a city with a population of more than 10 million). There are several effects in cities which strongly influence human health. Visible influences like the severe emissions of air pollutants by industry and traffic (e.g. Mayer H., 1999, Grimmond et al., 2010) are obvious to people but thermal stress in urban areas is only recently recognized for its strong devastating effect on human health. As a consequence, the urban environment virtually influences all weather parameters that have an impact on human comfort and thermal stress. Within this study, we investigate effects of city growth and the development of outlying districts on the local climate of Vienna. We focus particularly on the influence of urban heat island and consequent the risk for heat related illnesses or thermal stress for people. To quantify radiation balance and other important meteorological factors, we performed an extensive field campaign with three types of net radiometer in three different heights at BOKU site in August 2016. The first results indicated a strong correlation (ρ=0.96) between the Town Energy Balance (TEB) model and the measurements of the top net radiometer regarding radiation balance at roof level, meanwhile the TEB results are slightly underestimated. Further check if the measurements are reasonable, a comparison of the input values (global and direct solar radiation) for the TEB simulation with Secondary Standard measurements of ARAD site Wien Hohe Warte shows a deviation under 2% concerning interquartile range on clear sky days. The next steps will enclose TEB simulations, coupled with the mesoscale Weather Research and Forecasting (WRF) model, for

  9. Interaction of water, alkyl hydroperoxide, and allylic alcohol with a single-site homogeneous Ti-Si epoxidation catalyst: A spectroscopic and computational study.

    Science.gov (United States)

    Urakawa, Atsushi; Bürgi, Thomas; Skrabal, Peter; Bangerter, Felix; Baiker, Alfons

    2005-02-17

    Tetrakis(trimethylsiloxy)titanium (TTMST, Ti(OSiMe3)4) possesses an isolated Ti center and is a highly active homogeneous catalyst in epoxidation of various olefins. The structure of TTMST resembles that of the active sites in some heterogeneous Ti-Si epoxidation catalysts, especially silylated titania-silica mixed oxides. Water cleaves the Ti-O-Si bond and deactivates the catalyst. An alkyl hydroperoxide, TBHP (tert-butyl hydroperoxide), does not cleave the Ti-O-Si bond, but interacts via weak hydrogen-bonding as supported by NMR, DOSY, IR, and computational studies. ATR-IR spectroscopy combined with computational investigations shows that more than one, that is, up to four, TBHP can undergo hydrogen-bonding with TTMST, leading to the activation of the O-O bond of TBHP. The greater the number of TBHP molecules that form hydrogen bonds to TTMST, the more electrophilic the O-O bond becomes, and the more active the complex is for epoxidation. An allylic alcohol, 2-cyclohexen-1-ol, does not interact strongly with TTMST, but the interaction is prominent when it interacts with the TTMST-TBHP complex. On the basis of the experimental and theoretical findings, a hydrogen-bond-assisted epoxidation mechanism of TTMST is suggested.

  10. Analysis of the single and combined non-destructive test approaches for on-site concrete strength assessment: General statements based on a real case-study

    Directory of Open Access Journals (Sweden)

    Khoudja Ali-Benyahia

    2017-06-01

    Full Text Available The evaluation of the compressive strength of concrete in existing structures by coring is expensive, technically difficult in certain cases, and even impossible in others. The use of non-destructive testing (NDT is an interesting alternative method (i.e. affordable cost, portable, fast, etc.. However, the NDT estimation of strength requires a procedure of calibration of the model between NDT and compressive strength. The robustness of this calibration is a crucial point allowing better choice of the optimal number of cores. Studies which treat the calibration of proposed models are often based on laboratory experiments or synthetic data. The present study aims at identifying and optimizing the methodology of the calibration model on site. This paper is based on a broad campaign of auscultation using NDT (Rebound and Ultrasound and coring on an existing construction with 205 triplets of data (strengths and NDT results. Statistical data analysis enables to quantify the role of: the number of cores (NC used for the calibration, the use of only one or two-combined NDT techniques and the calibration method. The conclusions are focused on the improvement of the relevance and the effectiveness of NDT techniques in such operational situations.

  11. Tapered, Double-Lead Threads Single Implants Placed in Fresh Extraction Sockets and Healed Sites of the Posterior Jaws: A Multicenter Randomized Controlled Trial with 1 to 3 Years of Follow-Up.

    Science.gov (United States)

    Cucchi, Alessandro; Vignudelli, Elisabetta; Franco, Simonetta; Levrini, Luca; Castellani, Dario; Pagliani, Luca; Rea, Massimiliano; Modena, Claudio; Sandri, Giulio; Longhi, Carlo

    2017-01-01

    To evaluate the survival, success, and complication rates of tapered double-lead threads single implants, placed in fresh extraction sockets and healed sites of the posterior jaws. The enrolled patients were randomly divided into 2 groups: in the test group (TG), all implants were inserted at the time of tooth extraction; in the control group (CG), all implants were placed 3 months after extraction. The implants were followed for a period of 1 to 3 years after loading. The main outcomes were implant survival, complications, and implant-crown success. Ninety-two patients had 97 installed implants (49 in the TG, 48 in the CG). Only two implants failed, in the TG; the survival rates were therefore 95.9% (47/49) and 100% (48/48) for TG and CG, respectively. In the surviving implants, no complications were reported, for an implant-crown success of 100%. Although a significant difference was found in the levels of primary stability between TG and CG, single implants placed in fresh extraction sockets and healed sites of the posterior jaws had similar survival and complication rates. Crestal bone levels and peri-implant bone resorption showed similar values. A longer follow-up period is however required, to confirm these positive outcomes.

  12. Chemical shift changes provide evidence for overlapping single-stranded DNA and XPA binding sites on the 70 kDa subunit of human replication protein A

    Energy Technology Data Exchange (ETDEWEB)

    Daughdrill, Gary W.; Buchko, Garry W.; Botuyan, Maria V.; Arrowsmith, Cheryl H.; Wold, Marc S.; Kennedy, Michael A.; Lowry, David F.

    2003-07-15

    Replication protein A (RPA) is a heterotrimeric single-stranded DNA (ssDNA) binding protein that can form a complex with the xeroderma pigmentosum group A protein (XPA). This complex can preferentially recognize UV damaged DNA over undamaged DNA and has been implicated in the stabilization of open complex formation during nucleotide excision repair. In this report, NMR spectroscopy was used to investigate the interaction between a fragment of the 70 kDa subunit of human RPA, residues 1-326 (hRPA701-326), and a fragment of the human XPA protein, residues 98-219 (XPA-MBD). Intensity changes were observed for amide resonances in the 1H-15N correlation spectrum of uniformly 15N-labeled hRPA701-326 after the addition of unlabeled XPA-MBD. The intensity changes observed were restricted to an ssDNA binding domain that is between residues 183 and 296 of the hRPA701-326 fragment. The hRPA701-326 residues with the largest resonance intensity reductions were mapped onto the structure of the ssDNA binding domain to identify the binding surface with XPA-MBD. The XPA-MBD binding surface showed significant overlap with an ssDNA binding surface that was previously identified using NMR spectroscopy and X-ray crystallography.

  13. Single residue mutation in active site of serine acetyltransferase isoform 3 from Entamoeba histolytica assists in partial regaining of feedback inhibition by cysteine.

    Directory of Open Access Journals (Sweden)

    Sudhir Kumar

    Full Text Available The cysteine biosynthetic pathway is essential for survival of the protist pathogen Entamoeba histolytica, and functions by producing cysteine for countering oxidative attack during infection in human hosts. Serine acetyltransferase (SAT and O-acetylserine sulfhydrylase (OASS are involved in cysteine biosynthesis and are present in three isoforms each. While EhSAT1 and EhSAT2 are feedback inhibited by end product cysteine, EhSAT3 is nearly insensitive to such inhibition. The active site residues of EhSAT1 and of EhSAT3 are identical except for position 208, which is a histidine residue in EhSAT1 and a serine residue in EhSAT3. A combination of comparative modeling, multiple molecular dynamics simulations and free energy calculation studies showed a difference in binding energies of native EhSAT3 and of a S208H-EhSAT3 mutant for cysteine. Mutants have also been generated in vitro, replacing serine with histidine at position 208 in EhSAT3 and replacing histidine 208 with serine in EhSAT1. These mutants showed decreased affinity for substrate serine, as indicated by K(m, compared to the native enzymes. Inhibition kinetics in the presence of physiological concentrations of serine show that IC50 of EhSAT1 increases by about 18 folds from 9.59 µM for native to 169.88 µM for H208S-EhSAT1 mutant. Similar measurements with EhSAT3 confirm it to be insensitive to cysteine inhibition while its mutant (S208H-EhSAT3 shows a gain of cysteine inhibition by 36% and the IC50 of 3.5 mM. Histidine 208 appears to be one of the important residues that distinguish the serine substrate from the cysteine inhibitor.

  14. Addendum to the RCRA Assessment Report for Single-Shell Tank Waste Management Area S-SX at the Hanford Site

    International Nuclear Information System (INIS)

    Chou, C.J.; Johnson, V.G.

    1999-01-01

    The initial Resource Conservation and Recovery Act (RCRA) groundwater quality assessment report for Waste Management Area S-SX (PNNL-11810) was issued in January 1998. The report stated a plan for conducting continued assessment would be developed after addressing Washington State Department of Ecology (Ecology) comments on initial findings in PNNL-11810. Comments from Ecology were received by US Department of Energy, Richland Operations Office (DOE-RL) on September 24, 1998. Shortly thereafter, Ecology and DOE began dispute resolution and related negotiations about tank farm vadose issues. This led to proposed new Tri-Party Agreement milestones covering a RCRA Facility Investigation-Corrective Measures Study (RFI/CMS) of the four single-shell tank farm waste management areas that were in assessment status (Waste Management Areas B-BX-BY, S-SX, T and TX-TY). The RCRA Facility Investigation includes both subsurface (vadose zone and groundwater) and surface (waste handling facilities and grounds) characterization. Many of the Ecology comments on PNNL-11810 are more appropriate for, and in many cases are superseded by, the RFI/CMS at Waste Management Area S-SX. The proposed Tri-Party Agreement milestone changes that specify the scope and schedule for the RFI/CMS work plans (Tri-Party Agreement change number M-45-98-0) were issued for public comment in February 1999. The Tri-Party Agreement narrative indicates the ongoing groundwater assessments will be integrated with the RFI/CMS work plans. This addendum documents the disposition of the Ecology comments on PNNL-11810 and identifies which comments were more appropriate for the RFI/CMS work plan

  15. Addendum to the RCRA Assessment Report for Single-Shell Tank Waste Management Area S-SX at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Chou, C.J.; Johnson, V.G.

    1999-10-07

    The initial Resource Conservation and Recovery Act (RCRA) groundwater quality assessment report for Waste Management Area S-SX (PNNL-11810) was issued in January 1998. The report stated a plan for conducting continued assessment would be developed after addressing Washington State Department of Ecology (Ecology) comments on initial findings in PNNL-11810. Comments from Ecology were received by US Department of Energy, Richland Operations Office (DOE-RL) on September 24, 1998. Shortly thereafter, Ecology and DOE began dispute resolution and related negotiations about tank farm vadose issues. This led to proposed new Tri-Party Agreement milestones covering a RCRA Facility Investigation-Corrective Measures Study (RFI/CMS) of the four single-shell tank farm waste management areas that were in assessment status (Waste Management Areas B-BX-BY, S-SX, T and TX-TY). The RCRA Facility Investigation includes both subsurface (vadose zone and groundwater) and surface (waste handling facilities and grounds) characterization. Many of the Ecology comments on PNNL-11810 are more appropriate for, and in many cases are superseded by, the RFI/CMS at Waste Management Area S-SX. The proposed Tri-Party Agreement milestone changes that specify the scope and schedule for the RFI/CMS work plans (Tri-Party Agreement change number M-45-98-0) were issued for public comment in February 1999. The Tri-Party Agreement narrative indicates the ongoing groundwater assessments will be integrated with the RFI/CMS work plans. This addendum documents the disposition of the Ecology comments on PNNL-11810 and identifies which comments were more appropriate for the RFI/CMS work plan.

  16. Variation in antiviral 2',5'-oligoadenylate synthetase (2'5'AS) enzyme activity is controlled by a single-nucleotide polymorphism at a splice-acceptor site in the OAS1 gene

    DEFF Research Database (Denmark)

    Bonnevie-Nielsen, Vagn; Field, L Leigh; Lu, Shao

    2005-01-01

    It is likely that human genetic differences mediate susceptibility to viral infection and virus-triggered disorders. OAS genes encoding the antiviral enzyme 2',5'-oligoadenylate synthetase (2'5'AS) are critical components of the innate immune response to viruses. This enzyme uses adenosine......=.0044), but not spousal pairs, suggesting strong genetic control of basal activity. We next analyzed association between basal activity and 15 markers across the OAS gene cluster. Significant association was detected at multiple markers, the strongest being at an A/G single-nucleotide polymorphism...... at the exon 7 splice-acceptor site (AG or AA) of the OAS1 gene. At this unusual polymorphism, allele G had a higher gene frequency in persons with high enzyme activity than in those with low enzyme activity (0.44 vs. 0.20; P=3 x 10(-11)). Enzyme activity varied in a dose-dependent manner across the GG, GA...

  17. Synthesis, single-crystal structure refinement and Fe/T site preference in the ternary borides Fe {sub x}T{sub 7-x}B{sub 3} (T = Ru, Rh; 0 < x {<=} 1.5)

    Energy Technology Data Exchange (ETDEWEB)

    Fokwa, Boniface P.T. [Institut fuer Anorganische Chemie, Rheinisch-Westfaelische Technische Hochschule Aachen, D-52056 Aachen (Germany); Dronskowski, Richard [Institut fuer Anorganische Chemie, Rheinisch-Westfaelische Technische Hochschule Aachen, D-52056 Aachen (Germany)]. E-mail: drons@HAL9000.ac.rwth-aachen.de

    2007-01-31

    Single crystals of the borides Fe {sub x}Rh{sub 7-x}B{sub 3} (1 < x < 1.5) and Fe {sub x}Ru{sub 7-x}B{sub 3} (0 < x < 1) have been synthesized by arc-melting the elements in a water-cooled copper crucible under argon atmosphere. The silver-like products, structurally characterized by single-crystal X-ray analysis, adopt the hexagonal Th{sub 7}Fe{sub 3} structure type (space group P6{sub 3} mc, no. 186) with Z = 2. Their structures consist of layers of boron-centered trigonal prisms of rhodium or ruthenium (Rh;Ru) and iron on the one side, and one-dimensional channels of face-sharing octahedral (Rh;Ru){sub 6} clusters on the other. Unlike in FeRh{sub 6}B{sub 3}, the iron substitution takes place at two (6c and 2b) of the three available rhodium/ruthenium positions, with a preference for the 6c site in the case of the Fe {sub x}Rh{sub 7-x}B{sub 3} compounds but not for Fe {sub x}Ru{sub 7-x}B{sub 3}.

  18. 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.

  19. Crystal-field energy level analysis for Nd3+ ions at the low symmetry C1 site in [Nd(hfa)4(H2O)](N(C2H5)4) single crystals

    International Nuclear Information System (INIS)

    Mech, Agnieszka; Gajek, Zbigniew; Karbowiak, Miroslaw; Rudowicz, Czeslaw

    2008-01-01

    Optical absorption measurements of Nd 3+ ions in single crystals of [Nd(hfa) 4 (H 2 O)](N(C 2 H 5 ) 4 ) (hfa = hexafluoroacetyloacetonate), denoted Nd(hfa) for short, have been carried out at 4.2 and 298 K. This compound crystallizes in the monoclinic system (space group P 2 1 /n). Each Nd ion is coordinated to eight oxygen atoms that originate from the hexafluoroacetylacetonate ligands and one oxygen atom from the water molecule. A total of 85 experimental crystal-field (CF) energy levels arising from the Nd 3+ (4f 3 ) electronic configuration were identified in the optical spectra and assigned. A three-step CF analysis was carried out in terms of a parametric Hamiltonian for the actual C 1 symmetry at the Nd 3+ ion sites. In the first step, a total of 27 CF parameters (CFPs) in the Wybourne notation B kq , admissible by group theory, were determined in a preliminary fitting constrained by the angular overlap model predictions. The resulting CFP set was reduced to 24 specific independent CFPs using appropriate standardization transformations. Optimizations of the second-rank CFPs and extended scanning of the parameter space were employed in the second step to improve reliability of the CFP sets, which is rather a difficult task in the case of no site symmetry. Finally, seven free-ion parameters and 24 CFPs were freely varied, yielding an rms deviation between the calculated energy levels and the 85 observed ones of 11.1 cm -1 . Our approach also allows prediction of the energy levels of Nd 3+ ions that are hidden in the spectral range overlapping with strong ligand absorption, which is essential for understanding the inter-ionic energy transfer. The orientation of the axis system associated with the fitted CF parameters w.r.t. the crystallographic axes is established. The procedure adopted in our calculations may be considered as a general framework for analysis of CF levels of lanthanide ions at low (triclinic) symmetry sites

  20. Crystal-field energy level analysis for Nd(3+) ions at the low symmetry C(1) site in [Nd(hfa)(4)(H(2)O)](N(C(2)H(5))(4)) single crystals.

    Science.gov (United States)

    Mech, Agnieszka; Gajek, Zbigniew; Karbowiak, Mirosław; Rudowicz, Czesław

    2008-09-24

    Optical absorption measurements of Nd(3+) ions in single crystals of [Nd(hfa)(4)(H(2)O)](N(C(2)H(5))(4)) (hfa = hexafluoroacetyloacetonate), denoted Nd(hfa) for short, have been carried out at 4.2 and 298 K. This compound crystallizes in the monoclinic system (space group P 2(1)/n). Each Nd ion is coordinated to eight oxygen atoms that originate from the hexafluoroacetylacetonate ligands and one oxygen atom from the water molecule. A total of 85 experimental crystal-field (CF) energy levels arising from the Nd(3+) (4f(3)) electronic configuration were identified in the optical spectra and assigned. A three-step CF analysis was carried out in terms of a parametric Hamiltonian for the actual C(1) symmetry at the Nd(3+) ion sites. In the first step, a total of 27 CF parameters (CFPs) in the Wybourne notation B(kq), admissible by group theory, were determined in a preliminary fitting constrained by the angular overlap model predictions. The resulting CFP set was reduced to 24 specific independent CFPs using appropriate standardization transformations. Optimizations of the second-rank CFPs and extended scanning of the parameter space were employed in the second step to improve reliability of the CFP sets, which is rather a difficult task in the case of no site symmetry. Finally, seven free-ion parameters and 24 CFPs were freely varied, yielding an rms deviation between the calculated energy levels and the 85 observed ones of 11.1 cm(-1). Our approach also allows prediction of the energy levels of Nd(3+) ions that are hidden in the spectral range overlapping with strong ligand absorption, which is essential for understanding the inter-ionic energy transfer. The orientation of the axis system associated with the fitted CF parameters w.r.t. the crystallographic axes is established. The procedure adopted in our calculations may be considered as a general framework for analysis of CF levels of lanthanide ions at low (triclinic) symmetry sites.

  1. Crystal-field energy level analysis for Nd3+ ions at the low symmetry C1 site in [Nd(hfa)4(H2O)](N(C2H5)4) single crystals

    Science.gov (United States)

    Mech, Agnieszka; Gajek, Zbigniew; Karbowiak, Mirosław; Rudowicz, Czesław

    2008-09-01

    Optical absorption measurements of Nd3+ ions in single crystals of [Nd(hfa)4(H2O)](N(C2H5)4) (hfa = hexafluoroacetyloacetonate), denoted Nd(hfa) for short, have been carried out at 4.2 and 298 K. This compound crystallizes in the monoclinic system (space group P 21/n). Each Nd ion is coordinated to eight oxygen atoms that originate from the hexafluoroacetylacetonate ligands and one oxygen atom from the water molecule. A total of 85 experimental crystal-field (CF) energy levels arising from the Nd3+ (4f3) electronic configuration were identified in the optical spectra and assigned. A three-step CF analysis was carried out in terms of a parametric Hamiltonian for the actual C1 symmetry at the Nd3+ ion sites. In the first step, a total of 27 CF parameters (CFPs) in the Wybourne notation Bkq, admissible by group theory, were determined in a preliminary fitting constrained by the angular overlap model predictions. The resulting CFP set was reduced to 24 specific independent CFPs using appropriate standardization transformations. Optimizations of the second-rank CFPs and extended scanning of the parameter space were employed in the second step to improve reliability of the CFP sets, which is rather a difficult task in the case of no site symmetry. Finally, seven free-ion parameters and 24 CFPs were freely varied, yielding an rms deviation between the calculated energy levels and the 85 observed ones of 11.1 cm-1. Our approach also allows prediction of the energy levels of Nd3+ ions that are hidden in the spectral range overlapping with strong ligand absorption, which is essential for understanding the inter-ionic energy transfer. The orientation of the axis system associated with the fitted CF parameters w.r.t. the crystallographic axes is established. The procedure adopted in our calculations may be considered as a general framework for analysis of CF levels of lanthanide ions at low (triclinic) symmetry sites.

  2. The selectivity of the Na(+)/K(+)-pump is controlled by binding site protonation and self-correcting occlusion.

    Science.gov (United States)

    Rui, Huan; Artigas, Pablo; Roux, Benoît

    2016-08-04

    The Na(+)/K(+)-pump maintains the physiological K(+) and Na(+) electrochemical gradients across the cell membrane. It operates via an 'alternating-access' mechanism, making iterative transitions between inward-facing (E1) and outward-facing (E2) conformations. Although the general features of the transport cycle are known, the detailed physicochemical factors governing the binding site selectivity remain mysterious. Free energy molecular dynamics simulations show that the ion binding sites switch their binding specificity in E1 and E2. This is accompanied by small structural arrangements and changes in protonation states of the coordinating residues. Additional computations on structural models of the intermediate states along the conformational transition pathway reveal that the free energy barrier toward the occlusion step is considerably increased when the wrong type of ion is loaded into the binding pocket, prohibiting the pump cycle from proceeding forward. This self-correcting mechanism strengthens the overall transport selectivity and protects the stoichiometry of the pump cycle.

  3. Molecular mechanism of AMD3100 antagonism in the CXCR4 receptor: transfer of binding site to the CXCR3 receptor

    DEFF Research Database (Denmark)

    Rosenkilde, Mette M; Gerlach, Lars-Ole; Jakobsen, Janus S

    2004-01-01

    , respectively. Metal ion binding in the cyclam rings of AMD3100 increased its dependence on Asp(262) and provided a tighter molecular map of the binding site, where borderline mutational hits became clear hits for the Zn(II)-loaded analog. The proposed binding site for AMD3100 was confirmed by a gradual build......-up in the rather distinct CXCR3 receptor, for which the compound normally had no effect. Introduction of only a Glu at position VII:06 and the removal of a neutralizing Lys residue at position VII:02 resulted in a 1000-fold increase in affinity of AMD3100 to within 10-fold of its affinity in CXCR4. We conclude...

  4. The mutation frequency of 8-oxo-7,8 dihydroguanine (8-oxoG) situated in a multiply damaged site: comparison of a single and two closely opposed 8-oxodG in Escherichia coli

    International Nuclear Information System (INIS)

    Malyarchuk, S.G.; Youngblood, R.C.; Landry, A.M.; Quillin, E.; Harrison, L.

    2003-01-01

    Full text: A multiply damaged site (MDS) is defined as >= two lesions within a distance of 10-15 base pairs (bp). MDS generated by ionizing radiation contains oxidative base damage, and in vitro studies have indicated that if the base damage is less than 3 bp apart, repair of one lesion is inhibited until repair of the lesion in the opposite strand is completed. Inhibition of repair could result in an increase in the mutation frequency of the base damage. We have designed an assay to determine whether a closely opposed lesion causes an increase in adenine insertion opposite an 8-oxodG in bacteria. The double-stranded oligonucleotides (with no damage, each single 8-oxodG or the MDS) were ligated into the firefly luciferase coding region of a reporter vector and transformed into wild type or MutY-deficient bacteria. The MDS contained an 8-oxodG in the transcribed strand (T) and a second 8-oxodG immediately 5' to this lesion in the non-transcribed strand (NT). During two rounds of replication, insertion of adenine opposite the 8-oxodG in the T or NT strand results in a translation termination codon at position 444 or 445, respectively. In wild-type bacteria, we detected a translation stop at a frequency of 0.15% (codon 444) and 0.09% (codon 445) with a single 8-oxodG in the T or NT strand, respectively. This was enhanced ∼3 fold when single lesions were replicated in MutY-deficient bacteria. Positioning an 8-oxodG in the T strand within the MDS enhanced the mutation frequency by ∼2 fold in wild-type bacteria and 8 fold in Mut Y-deficient bacteria, while the mutation frequency of the 8-oxodG in the NT strand increased by 6 fold in Mut Y-deficient bacteria. This enhancement of mutation frequency supports the in vitro MDS studies, which demonstrated the inability of base excision repair to completely repair closely opposed lesions

  5. Site Features

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset consists of various site features from multiple Superfund sites in U.S. EPA Region 8. These data were acquired from multiple sources at different times...

  6. Site decontamination

    International Nuclear Information System (INIS)

    Bicker, A.E.

    1981-01-01

    Among the several DOE sites that have been radiologically decontaminated under the auspices of the Nevada Operations Office are three whose physical characteristics are unique. These are the Tatum Dome Test Site (TDTS) near Hattiesburg, Mississippi; a location of mountainous terrain (Pahute Mesa) on the Nevada Test Site; and the GNOME site near Carlsbad, New Mexico. In each case the contamination, the terrain, and the climate conditions were different. This presentation includes a brief description of each site, the methods used to perform radiological surveys, the logistics required to support the decontamination (including health physics and sample analysis), and the specific techniques used to reduce or remove the contamination

  7. Site organization and site arrangement

    International Nuclear Information System (INIS)

    Boissonnet, B.; Macqueron, J.F.

    1976-01-01

    The present paper deals with criteria for the choice of a production unit or power plant site, the organization and development of a site in terms of its particular characteristics and takes into account personnel considerations in site organizations as well as the problem of integrating the architecture into the environment. (RW) [de

  8. Effect of a single prophylactic preoperative oral antibiotic dose on surgical site infection following complex dermatological procedures on the nose and ear: a prospective, randomised, controlled, double-blinded trial.

    Science.gov (United States)

    Rosengren, Helena; Heal, Clare F; Buttner, Petra G

    2018-04-19

    There is limited published research studying the effect of antibiotic prophylaxis on surgical site infection (SSI) in dermatological surgery, and there is no consensus for its use in higher-risk cases. The objective of this study was to determine the effectiveness of a single oral preoperative 2 g dose of cephalexin in preventing SSI following flap and graft dermatological closures on the nose and ear. Prospective double-blinded, randomised, placebo-controlled trial testing for difference in infection rates. Primary care skin cancer clinics in North Queensland, Australia, were randomised to 2 g oral cephalexin or placebo 40-60 min prior to skin incision. 154 consecutive eligible patients booked for flap or graft closure following skin cancer excision on the ear and nose. 2 g dose of cephalexin administered 40-60 min prior to surgery. Overall 8/69 (11.6%) controls and 1/73 (1.4%) in the intervention group developed SSI (p=0.015; absolute SSI reduction 10.2%; number needed to treat (NNT) for benefit 9.8, 95% CI 5.5 to 45.5). In males, 7/44 controls and 0/33 in the intervention group developed SSI (p=0.018; absolute SSI reduction 15.9%; NNT for benefit 6.3, 95% CI 3.8 to 19.2). SSI was much lower in female controls (1/25) and antibiotic prophylaxis did not further reduce this (p=1.0). There was no difference between the study groups in adverse symptoms attributable to high-dose antibiotic administration (p=0.871). A single oral 2 g dose of cephalexin given before complex skin closure on the nose and ear reduced SSI. ANZCTR 365115; Post-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  9. Site operations

    International Nuclear Information System (INIS)

    House, W.B.; Ebenhack, D.G.

    1989-01-01

    This chapter is a discussion of the management and operations practices used at the Barnwell Waste Management Facility in Barnwell, SC. The following topics are discussed: (1) Waste receiving and inspection, including manifest and certificates of compliance, radiological surveys, disposition of nonconforming items, and decontamination and disposition of secondary waste streams; (2) Waste disposal, including Title 10 CFR 61 requirements, disposal area evaluations, shipment offloading, container emplacement, and radiation protection; (3) Trench closure, including trench backfilling, trench capping, and permanent markers; (4) Site maintenance and stabilization, including trench maintenance, surface water management, and site closure activities; (5) Site monitoring programs, including operational monitoring, and environmental monitoring program; (6) Personnel training and qualifications, including basic training program, safety training program, special skills training, and physical qualifications; (7) Records management, including waste records, personnel training records, personnel dosimetry records, site monitoring records, trench qualification and construction records, and site drawings and stabilization records; (8) Site security; (9) Emergency response plans; and (10) Quality assurance

  10. Spectroscopic studies on Titanium ion binding to the apo lactoferrin

    International Nuclear Information System (INIS)

    Moshtaghie, A.A.; Ani, M.; Arabi, M.H.

    2006-01-01

    Titanium is a relatively abundant element that has found growing applications in medical science and recently some of Titanium compounds are introduced as anticancer drugs. In spite of very limited data which exist on the Titanium metabolism, some proteins might be involved in the mechanism of action of Titanium up to our knowledge, there is not any report in the literature concerning binding of Titanium to apo lactoferrin. Binding of apo lactoferrin with Ti(IV)-citrate was studied by spectroflourimeterey and spectrophotometery techniques under physiological conditions. The spectroflourimeteric studies revealed a significant fluorescence quenching, that indicated binding of apo lactoferrin with Ti(IV). The same reaction was monitored through spectrophotometry technique; this represents a characteristic UV difference band at 267 nm, which is different from lac-Fe (III). Titration studies how that lactoferrin specifically binds two moles Ti(IV) as complex with citrate per mol protein. Spectroflourimeterey and spectrophotometery techniques indicated that Ti(IV) ions cause a reduction (13%-14%) in binding of Fe(III) to lactoferrin. In overall, we may come to this conclusion that this element might be involved in the iron metabolism

  11. Metal ion binding with dehydroannulenes – Plausible two ...

    Indian Academy of Sciences (India)

    WINTEC

    Theoretical investigations have been carried out at B3LYP/6-311++G** level of theory to study the binding ... Alkali metals; dehydroannulenes; binding energy; penetration barrier. 1. .... can be discriminated from larger metal ions by running.

  12. [Modification of retinal photoreceptor membranes and Ca ion binding].

    Science.gov (United States)

    Korchagin, V P; Berman, A L; Shukoliukov, S A; Rychkova, M P; Etingof, R N

    1978-10-01

    Calcium binding by modified photoreceptor membranes of cattle retina has been studied. Ca2+-binding the membranes significantly changes after C-phospholipase treatment, displaying the initial growth (less than 65% of lipid phosphorus removed) with subsequent decrease (more than 65% of phosphorus removed). Liposomes of the photoreceptor membranes lipids were found to bind more calcium than do the native photoreceptor membranes. Proteolytic enzymes (papaine, pronase) splitting some rhodopsin fragments do not affect the ability of the membrane to bind Ca2+. The increase of light-induced Ca-binding is observed only after the outer segments preincubation under conditions providing for rhodopsin phosphorylation. This effect was observed also after the splitting of the rhodopsin fragment by papaine. It is concluded that calcium binding in the photoreceptor membranes is mainly due to the phosphate groups of phospholipids.

  13. 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)

  14. Identification of cation-binding sites on actin that drive polymerization and modulate bending stiffness

    Science.gov (United States)

    Kang, Hyeran; Bradley, Michael J.; McCullough, Brannon R.; Pierre, Anaëlle; Grintsevich, Elena E.; Reisler, Emil; De La Cruz, Enrique M.

    2012-01-01

    The assembly of actin monomers into filaments and networks plays vital roles throughout eukaryotic biology, including intracellular transport, cell motility, cell division, determining cellular shape, and providing cells with mechanical strength. The regulation of actin assembly and modulation of filament mechanical properties are critical for proper actin function. It is well established that physiological salt concentrations promote actin assembly and alter the overall bending mechanics of assembled filaments and networks. However, the molecular origins of these salt-dependent effects, particularly if they involve nonspecific ionic strength effects or specific ion-binding interactions, are unknown. Here, we demonstrate that specific cation binding at two discrete sites situated between adjacent subunits along the long-pitch helix drive actin polymerization and determine the filament bending rigidity. We classify the two sites as “polymerization” and “stiffness” sites based on the effects that mutations at the sites have on salt-dependent filament assembly and bending mechanics, respectively. These results establish the existence and location of the cation-binding sites that confer salt dependence to the assembly and mechanics of actin filaments. PMID:23027950

  15. Protein kinase A (PKA) phosphorylation of Na+/K+-ATPase opens intracellular C-terminal water pathway leading to third Na+-binding site in molecular dynamics simulations

    DEFF Research Database (Denmark)

    Poulsen, Hanne; Nissen, Poul; Mouritsen, Ole G.

    2012-01-01

    -atom Molecular Dynamics (MD) simulations to investigate the structural consequences of phosphorylating the Na+/K+- ATPase (NKA) residue S936, which is the best characterized phosphorylation site in NKA, targeted in vivo by Protein Kinase A (PKA) (1-3). The MD simulations suggest that S936 phosphorylation opens......Phosphorylation is one of the major mechanisms for posttranscriptional modification of proteins. The addition of a compact, negatively charged moiety to a protein can significantly change its function and localization by affecting its structure and interaction network. We have used all...... a C-terminal hydrated pathway leading to D926, a transmembrane residue proposed to form part of the third sodium ion-binding site (4). Simulations of a S936E mutant form, for which only subtle effects are observed when expressed in Xenopus oocytes and studied with electrophysiology, does not mimic...

  16. 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...

  17. Europium ion as a probe for binding sites to carrageenans

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Ana P.; Goncalves, Rogeria R.; Serra, Osvaldo A. [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Ribeirao Preto, Sao Paulo 14040-901 (Brazil); Zaniquelli, Maria Elisabete D. [Departamento de Quimica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Ribeirao Preto, Sao Paulo 14040-901 (Brazil)], E-mail: medzaniquelli@ffclrp.usp.br; Wong, Kenneth [Laboratorio de Fisico-Quimica, Centro de Pesquisas de Paulinia, Rhodia Brasil, Paulinia, Sao Paulo (Brazil)

    2007-12-15

    Carrageenans, sulfated polysaccharides extracted from red algae, present a coil-helix transition and helix aggregation dependence on the type and concentration of counterions. In this study, we focus attention on a mixed valence counterion system: Eu{sup 3+}/Na{sup +} or K{sup +} with different gel-forming carrageenans: kappa, iota, and kappa-2. Results of stationary and time-dependent luminescence showed to be a suitable tool to probe ion binding to both the negatively charged sulfate group and the hydroxyl groups present in the biopolymer. For lower europium ion concentrations, a single longer decay emission lifetime was detected, which was attributed to the binding of europium ion to the carrageenan sulfate groups. An additional decay ascribed to europium binding to hydroxyl groups was observed above a threshold concentration, and this decay was dependent on the carrageenan charge density. Symmetry of the europium ion microenvironment was estimated by the ratio between the intensities of its emission bands, which has been shown to depend on the concentration of europium ions and on the specificity of the monovalent counterion bound to the carrageenan.

  18. Europium ion as a probe for binding sites to carrageenans

    International Nuclear Information System (INIS)

    Ramos, Ana P.; Goncalves, Rogeria R.; Serra, Osvaldo A.; Zaniquelli, Maria Elisabete D.; Wong, Kenneth

    2007-01-01

    Carrageenans, sulfated polysaccharides extracted from red algae, present a coil-helix transition and helix aggregation dependence on the type and concentration of counterions. In this study, we focus attention on a mixed valence counterion system: Eu 3+ /Na + or K + with different gel-forming carrageenans: kappa, iota, and kappa-2. Results of stationary and time-dependent luminescence showed to be a suitable tool to probe ion binding to both the negatively charged sulfate group and the hydroxyl groups present in the biopolymer. For lower europium ion concentrations, a single longer decay emission lifetime was detected, which was attributed to the binding of europium ion to the carrageenan sulfate groups. An additional decay ascribed to europium binding to hydroxyl groups was observed above a threshold concentration, and this decay was dependent on the carrageenan charge density. Symmetry of the europium ion microenvironment was estimated by the ratio between the intensities of its emission bands, which has been shown to depend on the concentration of europium ions and on the specificity of the monovalent counterion bound to the carrageenan

  19. Superfund Sites

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This layer represents active Superfund Sites published by the Environmental Protection Agency (EPA). These data were extracted from the Superfund Enterprise...

  20. Site development

    International Nuclear Information System (INIS)

    Noack, J.

    1975-01-01

    The subject of this paper is a general view over all necessary considerations to develop the site after it has been chosen and before starting with the construction of a nuclear power plant. (orig./RW) [de

  1. Site selection

    International Nuclear Information System (INIS)

    Olsen, C.W.

    1983-07-01

    The conditions and criteria for selecting a site for a nuclear weapons test at the Nevada Test Site are summarized. Factors considered are: (1) scheduling of drill rigs, (2) scheduling of site preparation (dirt work, auger hole, surface casing, cementing), (3) schedule of event (when are drill hole data needed), (4) depth range of proposed W.P., (5) geologic structure (faults, Pz contact, etc.), (6) stratigraphy (alluvium, location of Grouse Canyon Tuff, etc.), (7) material properties (particularly montmorillonite and CO 2 content), (8) water table depth, (9) potential drilling problems (caving), (10) adjacent collapse craters and chimneys, (11) adjacent expended but uncollapsed sites, (12) adjacent post-shot or other small diameter holes, (13) adjacent stockpile emplacement holes, (14) adjacent planned events (including LANL), (15) projected needs of Test Program for various DOB's and operational separations, and (16) optimal use of NTS real estate

  2. Structural dynamics of the box C/D RNA Kink-Turn and its complex with proteins: The role of the A-minor 0 interaction, long-residency water bridges, and structural ion-binding sites revealed by molecular simulations

    Czech Academy of Sciences Publication Activity Database

    Špačková, Naďa; Réblová, Kamila; Šponer, Jiří

    2010-01-01

    Roč. 114, č. 32 (2010), s. 10581-10593 ISSN 1520-6106 R&D Projects: GA MŠk(CZ) LC06030; GA AV ČR(CZ) KJB400040901; GA AV ČR(CZ) IAA400040802; GA ČR(CZ) GA203/09/1476 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : RNA-protein complex * molecular dynamics * kink-turn Subject RIV: BO - Biophysics Impact factor: 3.603, year: 2010

  3. Site development

    International Nuclear Information System (INIS)

    Gaynor, R.K.

    1989-01-01

    Development of a low-level radioactive waste land disposal facility is little different than any industrial development of similar scope. Consideration must be made for normal business and operations management, security, facility maintenance, traffic control and necessary amenities for personnel. The item specific to the low-level waste site is the handling of radioactive waste materials and the regulatory and environmental protection procedures that must be planned for and accomodated in the site design and development. Each of these elements and the facility as a whole must be designed to be compatible with local land use plans, available transportation and support services, and the social and economic goals of the local community. Plans should also be made for quality control and orderly construction. This chapter deals with those aspects of the facility, its design and construction which are integral parts to the overall performance of the site

  4. Site Practice

    DEFF Research Database (Denmark)

    Wahedi, Haseebullah

    2016-01-01

    different practices in the construction phase. The research is based on an ethnographic study of a case in Denmark. The empirical data were collected through direct observations and semi-structured interviews with site managers, contract managers, foremen and craftsmen. Findings revealed...... that the construction phase comprises several communities and practices, leading to various uses of the drawings. The results indicated that the craftsmen used drawings to position themselves in the correct location, and that the site managers and contract managers used them as management tools and legal documents...

  5. Evaluating the Effectiveness of an Antimicrobial Stewardship Program on Reducing the Incidence Rate of Healthcare-Associated Clostridium difficile Infection: A Non-Randomized, Stepped Wedge, Single-Site, Observational Study.

    Science.gov (United States)

    DiDiodato, Giulio; McArthur, Leslie

    2016-01-01

    The incidence rate of healthcare-associated Clostridium difficile infection (HA-CDI) is estimated at 1 in 100 patients. Antibiotic exposure is the most consistently reported risk factor for HA-CDI. Strategies to reduce the risk of HA-CDI have focused on reducing antibiotic utilization. Prospective audit and feedback is a commonly used antimicrobial stewardship intervention (ASi). The impact of this ASi on risk of HA-CDI is equivocal. This study examines the effectiveness of a prospective audit and feedback ASi on reducing the risk of HA-CDI. Single-site, 339 bed community-hospital in Barrie, Ontario, Canada. Primary outcome is HA-CDI incidence rate. Daily prospective and audit ASi is the exposure variable. ASi implemented across 6 wards in a non-randomized, stepped wedge design. Criteria for ASi; any intravenous antibiotic use for ≥ 48 hrs, any oral fluoroquinolone or oral second generation cephalosporin use for ≥ 48 hrs, or any antimicrobial use for ≥ 5 days. HA-CDI cases and model covariates were aggregated by ward, year and month starting September 2008 and ending February 2016. Multi-level mixed effect negative binomial regression analysis was used to model the primary outcome, with intercept and slope coefficients for ward-level random effects estimated. Other covariates tested for inclusion in the final model were derived from previously published risk factors. Deviance residuals were used to assess the model's goodness-of-fit. The dataset included 486 observation periods, of which 350 were control periods and 136 were intervention periods. After accounting for all other model covariates, the estimated overall ASi incidence rate ratio (IRR) was 0.48 (95% 0.30, 0.79). The ASi effect was independent of antimicrobial utilization. The ASi did not seem to reduce the risk of Clostridium difficile infection on the surgery wards (IRR 0.87, 95% CI 0.45, 1.69) compared to the medicine wards (IRR 0.42, 95% CI 0.28, 0.63). The ward-level burden of Clostridium

  6. Evaluating the Effectiveness of an Antimicrobial Stewardship Program on Reducing the Incidence Rate of Healthcare-Associated Clostridium difficile Infection: A Non-Randomized, Stepped Wedge, Single-Site, Observational Study.

    Directory of Open Access Journals (Sweden)

    Giulio DiDiodato

    Full Text Available The incidence rate of healthcare-associated Clostridium difficile infection (HA-CDI is estimated at 1 in 100 patients. Antibiotic exposure is the most consistently reported risk factor for HA-CDI. Strategies to reduce the risk of HA-CDI have focused on reducing antibiotic utilization. Prospective audit and feedback is a commonly used antimicrobial stewardship intervention (ASi. The impact of this ASi on risk of HA-CDI is equivocal. This study examines the effectiveness of a prospective audit and feedback ASi on reducing the risk of HA-CDI.Single-site, 339 bed community-hospital in Barrie, Ontario, Canada. Primary outcome is HA-CDI incidence rate. Daily prospective and audit ASi is the exposure variable. ASi implemented across 6 wards in a non-randomized, stepped wedge design. Criteria for ASi; any intravenous antibiotic use for ≥ 48 hrs, any oral fluoroquinolone or oral second generation cephalosporin use for ≥ 48 hrs, or any antimicrobial use for ≥ 5 days. HA-CDI cases and model covariates were aggregated by ward, year and month starting September 2008 and ending February 2016. Multi-level mixed effect negative binomial regression analysis was used to model the primary outcome, with intercept and slope coefficients for ward-level random effects estimated. Other covariates tested for inclusion in the final model were derived from previously published risk factors. Deviance residuals were used to assess the model's goodness-of-fit.The dataset included 486 observation periods, of which 350 were control periods and 136 were intervention periods. After accounting for all other model covariates, the estimated overall ASi incidence rate ratio (IRR was 0.48 (95% 0.30, 0.79. The ASi effect was independent of antimicrobial utilization. The ASi did not seem to reduce the risk of Clostridium difficile infection on the surgery wards (IRR 0.87, 95% CI 0.45, 1.69 compared to the medicine wards (IRR 0.42, 95% CI 0.28, 0.63. The ward-level burden of

  7. 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

  8. Site selection

    CERN Multimedia

    CERN PhotoLab

    1968-01-01

    To help resolve the problem of site selection for the proposed 300 GeV machine, the Council selected "three wise men" (left to right, J H Bannier of the Netherlands, A Chavanne of Switzerland and L K Boggild of Denmark).

  9. Site Restoration

    Energy Technology Data Exchange (ETDEWEB)

    Noynaert, L.; Bruggeman, A.; Cornelissen, R.; Massaut, V.; Rahier, A

    2001-04-01

    The objectives, the programme, and the achievements of the Site Restoration Department of SCK-CEN in 2000 are summarised. Main activities include the decommissioning of the BR3 PWR-reactor as well as other clean-up activities, projects on waste minimisation and activities related to the management of decommissioning projects. The department provides consultancy and services to external organisations.

  10. Site Restoration

    International Nuclear Information System (INIS)

    Noynaert, L.; Bruggeman, A.; Cornelissen, R.; Massaut, V.; Rahier, A.

    2001-01-01

    The objectives, the programme, and the achievements of the Site Restoration Department of SCK-CEN in 2000 are summarised. Main activities include the decommissioning of the BR3 PWR-reactor as well as other clean-up activities, projects on waste minimisation and activities related to the management of decommissioning projects. The department provides consultancy and services to external organisations

  11. 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)

  12. Domain-based small molecule binding site annotation

    Directory of Open Access Journals (Sweden)

    Dumontier Michel

    2006-03-01

    Full Text Available Abstract Background Accurate small molecule binding site information for a protein can facilitate studies in drug docking, drug discovery and function prediction, but small molecule binding site protein sequence annotation is sparse. The Small Molecule Interaction Database (SMID, a database of protein domain-small molecule interactions, was created using structural data from the Protein Data Bank (PDB. More importantly it provides a means to predict small molecule binding sites on proteins with a known or unknown structure and unlike prior approaches, removes large numbers of false positive hits arising from transitive alignment errors, non-biologically significant small molecules and crystallographic conditions that overpredict ion binding sites. Description Using a set of co-crystallized protein-small molecule structures as a starting point, SMID interactions were generated by identifying protein domains that bind to small molecules, using NCBI's Reverse Position Specific BLAST (RPS-BLAST algorithm. SMID records are available for viewing at http://smid.blueprint.org. The SMID-BLAST tool provides accurate transitive annotation of small-molecule binding sites for proteins not found in the PDB. Given a protein sequence, SMID-BLAST identifies domains using RPS-BLAST and then lists potential small molecule ligands based on SMID records, as well as their aligned binding sites. A heuristic ligand score is calculated based on E-value, ligand residue identity and domain entropy to assign a level of confidence to hits found. SMID-BLAST predictions were validated against a set of 793 experimental small molecule interactions from the PDB, of which 472 (60% of predicted interactions identically matched the experimental small molecule and of these, 344 had greater than 80% of the binding site residues correctly identified. Further, we estimate that 45% of predictions which were not observed in the PDB validation set may be true positives. Conclusion By

  13. single crystals

    Indian Academy of Sciences (India)

    2018-05-18

    May 18, 2018 ... Abstract. 4-Nitrobenzoic acid (4-NBA) single crystals were studied for their linear and nonlinear optical ... studies on the proper growth, linear and nonlinear optical ..... between the optic axes and optic sign of the biaxial crystal.

  14. 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

  15. Single Site Mutations in the Hetero-oligomeric Mrp Antiporter from Alkaliphilic Bacillus pseudofirmus OF4 That Affect Na+/H+ Antiport Activity, Sodium Exclusion, Individual Mrp Protein Levels, or Mrp Complex Formation*

    OpenAIRE

    Morino, Masato; Natsui, Shinsuke; Ono, Tomohiro; Swartz, Talia H.; Krulwich, Terry A.; Ito, Masahiro

    2010-01-01

    Mrp systems are widely distributed and structurally complex cation/proton antiporters. Antiport activity requires hetero-oligomeric complexes of all six or seven hydrophobic Mrp proteins (MrpA–MrpG). Here, a panel of site-directed mutants in conserved or proposed motif residues was made in the Mrp Na+(Li+)/H+ antiporter from an alkaliphilic Bacillus. The mutant operons were expressed in antiporter-deficient Escherichia coli KNabc and assessed for antiport properties, support of sodium resista...

  16. 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

  17. 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.

  18. Site Restoration

    Energy Technology Data Exchange (ETDEWEB)

    Noynaert, L.; Bruggeman, A.; Cornelissen, R.; Massaut, V.; Rahier, A

    2002-04-01

    The objectives, the programme, and the achievements of SCK-CEN's Site Restoration Department for 2001 are described. Main activities include the decommissioning of the BR3 PWR-reactor as well as other clean-up activities, projects on waste minimisation and the management of spent fuel and the flow of dismantled materials and the recycling of materials from decommissioning activities based on the smelting of metallic materials in specialised foundries. The department provides consultancy and services to external organisations and performs R and D on new techniques including processes for the treatment of various waste components including the reprocessing of spent fuel, the treatment of tritium, the treatment of liquid alkali metals into cabonates through oxidation, the treatment of radioactive organic waste and the reconditioning of bituminised waste products.

  19. Mochovce site

    International Nuclear Information System (INIS)

    1997-01-01

    In Mochovce site the construction of four units of WWER 440 NPP with V-213 type of reactor is being carried out. The financing of Mochovce units completion was resolved in April 1996. The completion work commenced at the construction site under leadership of SKODA Prague, the general supplier. The completion work on building part and tests of constructional electric distributions and lightning constructors started. The revisions in technological part were finished, and final protocols from revisions are the basis for starting of completion work. The assembly of transport container anchorage,ventilation system in hermetic areas and hermetic coverage of pools for stored spent nuclear fuel is being carried out. The pre-completion tests of instrumentation and control of ventilation systems, individual dosimetric control in medical station, and tests of nuclear programme according to commissioning and assembling work schedule at the equipment for physical protection of the NPP area started. Inspection activities at Mochovce were performed in accordance with inspection plan for 1996. Evaluation of routine inspections was performed by means of quarterly protocols. Main findings from the inspections performed in Mochovce were in the following areas: (a) deficiencies in the knowledge of the respective regulation and conditions from the Resolution of the state regulatory body, concerning selected employees; (b) training of the selected employees; (c) aim of the measures imposes by inspectors is to eliminate deficiencies in preparation of programmes for pre-completion and completion testing. NRA SR assessment activities at Mochovce NPP were focused mainly on approving and inspecting of design modification to approving programmes for pre-completion and completion testing of system s and equipment and on approving quality assurance programmes. The suggestions of international missions, which reviewed Mochovce safety in the years, were taken into consideration in the programme

  20. Strontium and barium in aqueous solution and a potassium channel binding site

    Science.gov (United States)

    Chaudhari, Mangesh I.; Rempe, Susan B.

    2018-06-01

    Ion hydration structure and free energy establish criteria for understanding selective ion binding in potassium (K+) ion channels and may be significant to understanding blocking mechanisms as well. Recently, we investigated the hydration properties of Ba2+, the most potent blocker of K+ channels among the simple metal ions. Here, we use a similar method of combining ab initio molecular dynamics simulations, statistical mechanical theory, and electronic structure calculations to probe the fundamental hydration properties of Sr2+, which does not block bacterial K+ channels. The radial distribution of water around Sr2+ suggests a stable 8-fold geometry in the local hydration environment, similar to Ba2+. While the predicted hydration free energy of -331.8 kcal/mol is comparable with the experimental result of -334 kcal/mol, the value is significantly more favorable than the -305 kcal/mol hydration free energy of Ba2+. When placed in the innermost K+ channel blocking site, the solvation free energies and lowest energy structures of both Sr2+ and Ba2+ are nearly unchanged compared with their respective hydration properties. This result suggests that the block is not attributable to ion trapping due to +2 charge, and differences in blocking behavior arise due to free energies associated with the exchange of water ligands for channel ligands instead of free energies of transfer from water to the binding site.

  1. Engineering of specific uranyl-coordination sites in the calcium-binding motif of Calmodulin

    International Nuclear Information System (INIS)

    Beccia, M.; Pardoux, R.; Sauge-Merle, S.; Bremond, N.; Lemaire, D.; Berthomieu, C.; Delangle, P.; Guilbaud, P.

    2014-01-01

    Complete text of publication follows: Characterization of heavy metals interactions with proteins is fundamental for understanding the molecular factors and mechanisms governing ions toxicity and speciation in cells. This line of research will also help in developing new molecules able to selectively and efficiently bind toxic metal ions, which could find application for bio-detection or bioremediation purposes. We have used the regulatory calcium-binding protein Calmodulin (CaM) from A. thaliana as a structural model and, starting from it, we have designed various mutants by site-directed mutagenesis. We have analysed thermodynamics of uranyl ion binding to both sites I and II of CaM N-terminal domain and we have identified structural factors governing this interaction. Selectivity for uranyl ion has been tested by studying reactions of the investigated peptides with Ca 2+ , in the same conditions used for UO 2 2+ . Spectro-fluorimetric titrations and FTIR analysis have shown that the affinity for uranyl increases by phosphorylation of a threonine in site I, especially approaching the physiological pH, where the phospho-threonine side chain is deprotonated. Based on structural models obtained by Molecular Dynamics, we tested the effect of a two residues deletion on site I properties. We obtained an almost two orders of magnitude increase in affinity for uranyl, with a sub-nanomolar dissociation constant for the uranyl complex with the non phosphorylated peptide, and an improved uranyl/calcium selectivity. Allosteric effects depending on Ca 2+ and UO 2 2+ binding have been investigated by comparing thermodynamic parameters obtained for mutants having both sites I and II able to chelate metal ions with those of mutants consisting of just one active site

  2. Singled out?

    Science.gov (United States)

    Waller, Frank

    2004-03-01

    The increasing use of single use medical devices is being driven by a growing awareness of iatrogenic (from the Greek; caused by the doctor) and nosocomial infections. Public health perceptions relating to transmissible spongiform encephalopathies, specifically variant Creutzfeldt-Jakob disease (vCJD), the Human Immunodeficiency Virus (HIV) and Hepatitis B are high on the political agenda and a matter of concern to healthcare professionals.

  3. Well installation, single-well testing, and particle-size analysis for selected sites in and near the Lost Creek Designated Ground Water Basin, north-central Colorado, 2003-2004

    Science.gov (United States)

    Beck, Jennifer A.; Paschke, Suzanne S.; Arnold, L. Rick

    2011-01-01

    This report describes results from a groundwater data-collection program completed in 2003-2004 by the U.S. Geological Survey in support of the South Platte Decision Support System and in cooperation with the Colorado Water Conservation Board. Two monitoring wells were installed adjacent to existing water-table monitoring wells. These wells were installed as well pairs with existing wells to characterize the hydraulic properties of the alluvial aquifer and shallow Denver Formation sandstone aquifer in and near the Lost Creek Designated Ground Water Basin. Single-well tests were performed in the 2 newly installed wells and 12 selected existing monitoring wells. Sediment particle size was analyzed for samples collected from the screened interval depths of each of the 14 wells. Hydraulic-conductivity and transmissivity values were calculated after the completion of single-well tests on each of the selected wells. Recovering water-level data from the single-well tests were analyzed using the Bouwer and Rice method because test data most closely resembled those obtained from traditional slug tests. Results from the single-well test analyses for the alluvial aquifer indicate a median hydraulic-conductivity value of 3.8 x 10-5 feet per second and geometric mean hydraulic-conductivity value of 3.4 x 10-5 feet per second. Median and geometric mean transmissivity values in the alluvial aquifer were 8.6 x 10-4 feet squared per second and 4.9 x 10-4 feet squared per second, respectively. Single-well test results for the shallow Denver Formation sandstone aquifer indicate a median hydraulic-conductivity value of 5.4 x 10-6 feet per second and geometric mean value of 4.9 x 10-6 feet per second. Median and geometric mean transmissivity values for the shallow Denver Formation sandstone aquifer were 4.0 x 10-5 feet squared per second and 5.9 x 10-5 feet squared per second, respectively. Hydraulic-conductivity values for the alluvial aquifer in and near the Lost Creek Designated

  4. Single-tooth implant restorations in the esthetic zone--contemporary concepts for optimization and maintenance of soft tissue esthetics in the replacement of failing teeth in compromised sites.

    Science.gov (United States)

    Mankoo, Tidu

    2007-01-01

    In recent years, implant dentistry has undergone a profound shift in emphasis. The focus evolved first from a surgically driven approach to a prosthetically driven approach and now to a more biologically driven approach with the goal of optimizing and maintaining esthetics. While traditional implant protocols are well established for management of implants placed in healed edentulous sites, the data available offer little clarity on the factors and procedures for long-term esthetic success, particularly in terms of maintained stable soft tissue outcomes around implant restorations in the esthetic zone. Unfortunately, the 90%+ success rates indicated in most studies of dental implant systems today do not represent the success of the esthetic outcome. This has created a demand--certainly among clinicians in private practice focused on the ongoing maintenance of esthetic outcomes--for clear treatment protocols to achieve esthetic results that are not only predictable and consistent but that can withstand the test of time.

  5. Single site mutations in the hetero-oligomeric Mrp antiporter from alkaliphilic Bacillus pseudofirmus OF4 that affect Na+/H+ antiport activity, sodium exclusion, individual Mrp protein levels, or Mrp complex formation.

    Science.gov (United States)

    Morino, Masato; Natsui, Shinsuke; Ono, Tomohiro; Swartz, Talia H; Krulwich, Terry A; Ito, Masahiro

    2010-10-01

    Mrp systems are widely distributed and structurally complex cation/proton antiporters. Antiport activity requires hetero-oligomeric complexes of all six or seven hydrophobic Mrp proteins (MrpA-MrpG). Here, a panel of site-directed mutants in conserved or proposed motif residues was made in the Mrp Na(+)(Li(+))/H(+) antiporter from an alkaliphilic Bacillus. The mutant operons were expressed in antiporter-deficient Escherichia coli KNabc and assessed for antiport properties, support of sodium resistance, membrane levels of each Mrp protein, and presence of monomeric and dimeric Mrp complexes. Antiport did not depend on a VFF motif or a conserved tyrosine pair, but a role for a conserved histidine in a potential quinone binding site of MrpA was supported. The importance of several acidic residues for antiport was confirmed, and the importance of additional residues was demonstrated (e.g. three lysine residues conserved across MrpA, MrpD, and membrane-bound respiratory Complex I subunits (NuoL/M/N)). The results extended indications that MrpE is required for normal membrane levels of other Mrp proteins and for complex formation. Moreover, mutations in several other Mrp proteins lead to greatly reduced membrane levels of MrpE. Thus, changes in either of the two Mrp modules, MrpA-MrpD and MrpE-MrpG, influence the other. Two mutants, MrpB-P37G and MrpC-Q70A, showed a normal phenotype but lacked the MrpA-MrpG monomeric complex while retaining the dimeric hetero-oligomeric complex. Finally, MrpG-P81A and MrpG-P81G mutants exhibited no antiport activity but supported sodium resistance and a low [Na(+)](in). Such mutants could be used to screen hypothesized but uncharacterized sodium efflux functions of Mrp apart from Na(+) (Li(+))/H(+) antiport.

  6. Investigating the widely held belief that men and women with learning disabilities receive poor quality healthcare when admitted to hospital: a single-site study of 30-day readmission rates.

    Science.gov (United States)

    Kelly, C L; Thomson, K; Wagner, A P; Waters, J P; Thompson, A; Jones, S; Holland, A J; Redley, M

    2015-09-01

    This study aims to use 30-day readmission rates to investigate the presumption that men and women with learning disabilities (LDs, known internationally as intellectual disabilities) receive poorer quality hospital care than their non-disabled peers. A 12-month retrospective audit was conducted using Hospital Episode Statistics (HES) at a single acute hospital in the East of England. This identified all in-patient admissions; admissions where the person concerned was recognised as having a LD; and all emergency readmissions within 30 days of discharge. Additionally, the healthcare records of all patients identified as having a LD and readmitted within 30 days as a medical emergency were examined in order to determine whether or not these readmissions were potentially preventable. Over the study period, a total of 66 870 adults were admitted as in-patients, among whom 7408 were readmitted as medical emergencies within 30 days of discharge: a readmission rate of 11%. Of these 66 870 patients, 256 were identified as having a LD, with 32 of them experiencing at least one emergency readmission within 30 days: a readmission rate of 13%. When examined, the healthcare records pertaining to these 32 patients who had a total of 39 unique 30-day readmissions revealed that 69% (n = 26) of these readmissions were potentially preventable. Although overall readmission rates were similar for patients with LDs and those from the general population, patients with LDs had a much higher rate of potentially preventable readmissions when compared to a general population estimate from van Walraven et al. This suggests that there is still work to be done to ensure that this patient population receives hospital care that is both safe and of high quality. © 2015 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

  7. Conformational changes associated with the binding of zinc acetate at the putative active site of XcTcmJ, a cupin from Xanthomonas campestris pv. campestris

    International Nuclear Information System (INIS)

    Axelrod, Herbert L.; Kozbial, Piotr; McMullan, Daniel; Krishna, S. Sri; Miller, Mitchell D.; Abdubek, Polat; Acosta, Claire; Astakhova, Tamara; Carlton, Dennis; Caruthers, Jonathan; Chiu, Hsiu-Ju; Clayton, Thomas; Deller, Marc C.; Duan, Lian; Elias, Ylva; Feuerhelm, Julie; Grzechnik, Slawomir K.; Grant, Joanna C.; Han, Gye Won; Jaroszewski, Lukasz; Jin, Kevin K.; Klock, Heath E.; Knuth, Mark W.; Kumar, Abhinav; Marciano, David; Morse, Andrew T.; Murphy, Kevin D.; Nigoghossian, Edward; Okach, Linda; Oommachen, Silvya; Paulsen, Jessica; Reyes, Ron; Rife, Christopher L.; Tien, Henry J.; Trout, Christina V.; Bedem, Henry van den; Weekes, Dana; White, Aprilfawn; Xu, Qingping; Zubieta, Chloe; Hodgson, Keith O.; Wooley, John; Elsliger, Marc-André; Deacon, Ashley M.; Godzik, Adam; Lesley, Scott A.; Wilson, Ian A.

    2009-01-01

    The crystal structure of an RmlC-type cupin with zinc acetate bound at the putative active site reveals significant differences from a previous structure without any bound ligand. The functional implications of the ligand-induced conformational changes are discussed. In the plant pathogen Xanthomonas campestris pv. campestris, the product of the tcmJ gene, XcTcmJ, encodes a protein belonging to the RmlC family of cupins. XcTcmJ was crystallized in a monoclinic space group (C2) in the presence of zinc acetate and the structure was determined to 1.6 Å resolution. Previously, the apo structure has been reported in the absence of any bound metal ion [Chin et al. (2006 ▶), Proteins, 65, 1046–1050]. The most significant difference between the apo structure and the structure of XcTcmJ described here is a reorganization of the binding site for zinc acetate, which was most likely acquired from the crystallization solution. This site is located in the conserved metal ion-binding domain at the putative active site of XcTcmJ. In addition, an acetate was also bound within coordination distance of the zinc. In order to accommodate this binding, rearrangement of a conserved histidine ligand is required as well as several nearby residues within and around the putative active site. These observations indicate that binding of zinc serves a functional role in this cupin protein

  8. Contaminated Sites in Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Sites contaminated by hazardous materials or wastes. These sites are those administered by the Contaminated Sites Section of Iowa DNR. Many are sites which are...

  9. 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...

  10. The selectivity of the Na+/K+-pump is controlled by binding site protonation and self-correcting occlusion

    Science.gov (United States)

    Rui, Huan; Artigas, Pablo; Roux, Benoît

    2016-01-01

    The Na+/K+-pump maintains the physiological K+ and Na+ electrochemical gradients across the cell membrane. It operates via an 'alternating-access' mechanism, making iterative transitions between inward-facing (E1) and outward-facing (E2) conformations. Although the general features of the transport cycle are known, the detailed physicochemical factors governing the binding site selectivity remain mysterious. Free energy molecular dynamics simulations show that the ion binding sites switch their binding specificity in E1 and E2. This is accompanied by small structural arrangements and changes in protonation states of the coordinating residues. Additional computations on structural models of the intermediate states along the conformational transition pathway reveal that the free energy barrier toward the occlusion step is considerably increased when the wrong type of ion is loaded into the binding pocket, prohibiting the pump cycle from proceeding forward. This self-correcting mechanism strengthens the overall transport selectivity and protects the stoichiometry of the pump cycle. DOI: http://dx.doi.org/10.7554/eLife.16616.001 PMID:27490484

  11. 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.

  12. Nuclear installations sites safety

    International Nuclear Information System (INIS)

    Barber, P.; Candes, P.; Duclos, P.; Doumenc, A.; Faure, J.; Hugon, J.; Mohammadioun, B.

    1988-11-01

    This report is divided into ten parts bearing: 1 Safety analysis procedures for Basis Nuclear Installations sites (BNI) in France 2 Site safety for BNI in France 3 Industrial and transport activities risks for BNI in France 4 Demographic characteristics near BNI sites in France 5 Meteorologic characteristics of BNI sites in France 6 Geological aspects near the BNI sites in France 7 Seismic studies for BNI sites in France 8 Hydrogeological aspects near BNI sites in France 9 Hydrological aspects near BNI sites in France 10 Ecological and radioecological studies of BNI sites in France [fr

  13. Social Media Sites

    Science.gov (United States)

    Media Sites Site Registration Contact Us Search AF.mil: Home > AF Sites > Social Media Sites Social Media Welcome to the Air Force social media directory! The directory is a one-stop shop of official Air Force social media pages across various social media sites. Social media is all about

  14. Ocean Disposal Site Monitoring

    Science.gov (United States)

    EPA is responsible for managing all designated ocean disposal sites. Surveys are conducted to identify appropriate locations for ocean disposal sites and to monitor the impacts of regulated dumping at the disposal sites.

  15. Promoting Your Web Site.

    Science.gov (United States)

    Raeder, Aggi

    1997-01-01

    Discussion of ways to promote sites on the World Wide Web focuses on how search engines work and how they retrieve and identify sites. Appropriate Web links for submitting new sites and for Internet marketing are included. (LRW)

  16. Particle Physics Education Sites

    Science.gov (United States)

    back to home page Particle Physics Education Sites quick reference Education and Information - National Laboratory Education Programs - Women and Minorities in Physics - Other Physics Sites - Physics Alliance - Accelerators at National Laboratories icon Particle Physics Education and Information sites: top

  17. Intramolecular electron transfer in single-site-mutated azurins

    DEFF Research Database (Denmark)

    Farver, O; Skov, L K; Pascher, T

    1993-01-01

    . Natl. Acad. Sci. U.S.A. 86, 6968-6972]. The RSSR- radical produced in the above reaction was reoxidized in a slower intramolecular electron-transfer process (30-70 s-1 at 298 K) concomitant with a further reduction of the Cu(II) ion. The temperature dependence of the latter rates was determined......, lambda = 135 kJ mol-1 for the reorganization energy was derived. When Trp48, situated midway between the donor and the acceptor, was replaced by Leu or Met, only a small change in the rate of intramolecular electron transfer was observed, indicating that the aromatic residue in this position...... is apparently only marginally involved in electron transfer in wild-type azurin. Pathway calculations also suggest that a longer, through-backbone path is more efficient than the shorter one involving Trp48. The former pathway yields an exponential decay factor, beta, of 6.6 nm-1. Another mutation, raising...

  18. Oxygen reduction and evolution at single-metal active sites

    DEFF Research Database (Denmark)

    Calle-Vallejo, F.; Martínez, J.I.; García Lastra, Juan Maria

    2013-01-01

    A worldwide spread of clean technologies such as low-temperature fuel cells and electrolyzers depends strictly on their technical reliability and economic affordability. Currently, both conditions are hardly fulfilled mainly due to the same reason: the oxygen electrode, which has large overpotent...

  19. Hanford Site Development Plan

    Energy Technology Data Exchange (ETDEWEB)

    Rinne, C.A.; Curry, R.H.; Hagan, J.W.; Seiler, S.W.; Sommer, D.J. (Westinghouse Hanford Co., Richland, WA (USA)); Yancey, E.F. (Pacific Northwest Lab., Richland, WA (USA))

    1990-01-01

    The Hanford Site Development Plan (Site Development Plan) is intended to guide the short- and long-range development and use of the Hanford Site. All acquisition, development, and permanent facility use at the Hanford Site will conform to the approved plan. The Site Development Plan also serves as the base document for all subsequent studies that involve use of facilities at the Site. This revision is an update of a previous plan. The executive summary presents the highlights of the five major topics covered in the Site Development Plan: general site information, existing conditions, planning analysis, Master Plan, and Five-Year Plan. 56 refs., 67 figs., 31 tabs.

  20. Hanford Site Development Plan

    International Nuclear Information System (INIS)

    Rinne, C.A.; Curry, R.H.; Hagan, J.W.; Seiler, S.W.; Sommer, D.J.; Yancey, E.F.

    1990-01-01

    The Hanford Site Development Plan (Site Development Plan) is intended to guide the short- and long-range development and use of the Hanford Site. All acquisition, development, and permanent facility use at the Hanford Site will conform to the approved plan. The Site Development Plan also serves as the base document for all subsequent studies that involve use of facilities at the Site. This revision is an update of a previous plan. The executive summary presents the highlights of the five major topics covered in the Site Development Plan: general site information, existing conditions, planning analysis, Master Plan, and Five-Year Plan. 56 refs., 67 figs., 31 tabs

  1. SITE COMPREHENSIVE LISTING (CERCLIS) (Superfund) - NPL Sites

    Data.gov (United States)

    U.S. Environmental Protection Agency — National Priorities List (NPL) Sites - The Comprehensive Environmental Response, Compensation and Liability Information System (CERCLIS) (Superfund) Public Access...

  2. Superfund Site Information - Site Sampling Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — This asset includes Superfund site-specific sampling information including location of samples, types of samples, and analytical chemistry characteristics of...

  3. Site Closure Strategy Model for Creosote Site

    International Nuclear Information System (INIS)

    Coll, F.R.; Gray, D.R.

    2009-01-01

    In conjunction with RCRA site corrective action at an active wood preserving facility, a risk-based site closure strategy was developed and incorporated the performance of a dense non-aqueous phase liquid (DNAPL) source recovery remedy, a monitored natural attenuation (MNA) remedy for dissolved phase groundwater, and institutional controls. Innovative creosote DNAPL source recovery has been undertaken at the Site since 1998. Pooled creosote DNAPL is present 90 feet below ground within a transmissive sand and gravel aquifer with a saturated thickness of approximately 80 feet. The creosote DNAPL source is situated on the property boundary of the site and has generated a 1/2 mile off-site dissolved phase plume, creating significant NAPL management and remedial technology verification issues. To date, over 120,000 gallons of creosote DNAPL have been recovered from the subsurface utilizing a modified circulation well technology. A mass discharge flux protocol was developed to serve as a major performance metrics for the continuation of source removal efforts and to support the application of monitored natural attenuation as an associated remedial technology for groundwater. The mass removal success has supported the MNA remedy for dissolved phase groundwater and the associated development of institutional controls. The enacted site management strategy outlines the current and future risk management activities for the Site and represents an appropriate site closure strategy for the Site. (authors)

  4. Site specific information in site selection

    International Nuclear Information System (INIS)

    Aeikaes, T.; Hautojaervi, A.

    1998-01-01

    The programme for the siting of a deep repository for final disposal of spent nuclear fuel was started already in 1983 and is carried out today by Posiva Oy which continues the work started by Teollisuuden Voima Oy. The programme aims at site selection by the end of the year 2000. The programme has progressed in successive interim stages with defined goals. After an early phase for site identification, five sites were selected in 1987 for preliminary site characterisation. Three of these were selected and judged to be best suited for the more detailed characterisation in 1992. An additional new site was included into the programme based on a separate feasibility study in the beginning of 1997. Since the year 1983 several safety assessments together with technical plans of the facility have been completed. When approaching the site selection the needs for more detailed consideration of the site specific properties in the safety assessment have been increased. The Finnish regulator STUK has published a proposal for general safety requirements for the final disposal of spent nuclear fuel in Finland. This set of requirements has been projected to be used in conjunction of the decision making by the end 2000. Based on the site evaluation all sites can provide a stable environment and there is evidence that the requirements for the longevity of the canister can be fulfilled at each site. In this manner the four candidate sites do not differ too much from each other. The main difference between the sites is in the salinity of the deep groundwater. The significance of differences in the salinity for the long-term safety cannot be defined yet. The differences may contribute to the discussion of the longevity of the bentonite buffer and also to the modelling of the groundwater flow and transport. The use of the geosphere as a transport barrier is basically culminated on the questions about sparse but fast flow routes and 'how bad channeling can be'. To answer these questions

  5. Hanford Site Development Plan

    International Nuclear Information System (INIS)

    Hathaway, H.B.; Daly, K.S.; Rinne, C.A.; Seiler, S.W.

    1993-05-01

    The Hanford Site Development Plan (HSDP) provides an overview of land use, infrastructure, and facility requirements to support US Department of Energy (DOE) programs at the Hanford Site. The HSDP's primary purpose is to inform senior managers and interested parties of development activities and issues that require a commitment of resources to support the Hanford Site. The HSDP provides an existing and future land use plan for the Hanford Site. The HSDP is updated annually in accordance with DOE Order 4320.1B, Site Development Planning, to reflect the mission and overall site development process. Further details about Hanford Site development are defined in individual area development plans

  6. Region 9 NPL Sites (Superfund Sites 2013)

    Science.gov (United States)

    NPL site POINT locations for the US EPA Region 9. NPL (National Priorities List) sites are hazardous waste sites that are eligible for extensive long-term cleanup under the Superfund program. Eligibility is determined by a scoring method called Hazard Ranking System. Sites with high scores are listed on the NPL. The majority of the locations are derived from polygon centroids of digitized site boundaries. The remaining locations were generated from address geocoding and digitizing. Area covered by this data set include Arizona, California, Nevada, Hawaii, Guam, American Samoa, Northern Marianas and Trust Territories. Attributes include NPL status codes, NPL industry type codes and environmental indicators. Related table, NPL_Contaminants contains information about contaminated media types and chemicals. This is a one-to-many relate and can be related to the feature class using the relationship classes under the Feature Data Set ENVIRO_CONTAMINANT.

  7. Crystal-field energy level analysis for Nd{sup 3+} ions at the low symmetry C{sub 1} site in [Nd(hfa){sub 4}(H{sub 2}O)](N(C{sub 2}H{sub 5}){sub 4}) single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Mech, Agnieszka; Gajek, Zbigniew [Institute of Low Temperature and Structure Research, Polish Academy Of Sciences, ulica Okolna 2, 54-422 Wroclaw (Poland); Karbowiak, Miroslaw [Faculty of Chemistry, University of Wroclaw, ulica F Joliot-Curie 14, 50-383 Wroclaw (Poland); Rudowicz, Czeslaw [Institute of Physics, Szczecin University of Technology, Aleja Piastow 17, 70-310 Szczecin (Poland)], E-mail: karb@wchuwr.pl

    2008-09-24

    Optical absorption measurements of Nd{sup 3+} ions in single crystals of [Nd(hfa){sub 4}(H{sub 2}O)](N(C{sub 2}H{sub 5}){sub 4}) (hfa = hexafluoroacetyloacetonate), denoted Nd(hfa) for short, have been carried out at 4.2 and 298 K. This compound crystallizes in the monoclinic system (space group P 2{sub 1}/n). Each Nd ion is coordinated to eight oxygen atoms that originate from the hexafluoroacetylacetonate ligands and one oxygen atom from the water molecule. A total of 85 experimental crystal-field (CF) energy levels arising from the Nd{sup 3+} (4f{sup 3}) electronic configuration were identified in the optical spectra and assigned. A three-step CF analysis was carried out in terms of a parametric Hamiltonian for the actual C{sub 1} symmetry at the Nd{sup 3+} ion sites. In the first step, a total of 27 CF parameters (CFPs) in the Wybourne notation B{sub kq}, admissible by group theory, were determined in a preliminary fitting constrained by the angular overlap model predictions. The resulting CFP set was reduced to 24 specific independent CFPs using appropriate standardization transformations. Optimizations of the second-rank CFPs and extended scanning of the parameter space were employed in the second step to improve reliability of the CFP sets, which is rather a difficult task in the case of no site symmetry. Finally, seven free-ion parameters and 24 CFPs were freely varied, yielding an rms deviation between the calculated energy levels and the 85 observed ones of 11.1 cm{sup -1}. Our approach also allows prediction of the energy levels of Nd{sup 3+} ions that are hidden in the spectral range overlapping with strong ligand absorption, which is essential for understanding the inter-ionic energy transfer. The orientation of the axis system associated with the fitted CF parameters w.r.t. the crystallographic axes is established. The procedure adopted in our calculations may be considered as a general framework for analysis of CF levels of lanthanide ions at low

  8. 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....

  9. 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

  10. The nature of cationic adsorption sites in alkaline zeolites-single, dual and multiple cation sites

    Czech Academy of Sciences Publication Activity Database

    Nachtigall, P.; Delgado, M. R.; Nachtigallová, Dana; Arean, C. O.

    2012-01-01

    Roč. 14, č. 5 (2012), s. 1552-1569 ISSN 1463-9076 R&D Projects: GA ČR GA203/09/0143 Institutional research plan: CEZ:AV0Z40550506 Keywords : exchanged ZSM-5 zeolites * carbon-monoxide adsorption * low-temperature CO * solid-state NMR * high-silica zeolites Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.829, year: 2012

  11. NPL Site Locations

    Data.gov (United States)

    U.S. Environmental Protection Agency — The National Priorities List (NPL) is a list published by EPA of Superfund sites. A site must be added to this list before remediation can begin under Superfund. The...

  12. Site Area Boundaries

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset consists of site boundaries from multiple Superfund sites in U.S. EPA Region 8. These data were acquired from multiple sources at different times and...

  13. NPL Site Boundaries

    Data.gov (United States)

    U.S. Environmental Protection Agency — The National Priorities List (NPL) is a list published by EPA of Superfund sites. A site must be added to this list before remediation can begin under Superfund. The...

  14. Drupal 7 Multilingual Sites

    CERN Document Server

    Pol, Kristen

    2012-01-01

    A practical book with plenty of screenshots to guide you through the many features of multilingual Drupal. A demo ecommerce site is provided if you want to practice on a sample site, although you can apply the techniques learnt in the book directly to your site too. Any Drupal users who know the basics of building a Drupal site and are familiar with the Drupal UI, will benefit from this book. No previous knowledge of localization or internationalization is required.

  15. Nuclear waste repository siting

    International Nuclear Information System (INIS)

    Soloman, B.D.; Cameron, D.M.

    1987-01-01

    This paper discusses the geopolitics of nuclear waste disposal in the USA. Constitutional choice and social equity perspectives are used to argue for a more open and just repository siting program. The authors assert that every potential repository site inevitably contains geologic, environmental or other imperfections and that the political process is the correct one for determining sites selected

  16. Site Calibration report

    DEFF Research Database (Denmark)

    Yordanova, Ginka; Vesth, Allan

    The report describes site calibration measurements carried out on a site in Denmark. The measurements are carried out in accordance to Ref. [1]. The site calibration is carried out before a power performance measurement on a given turbine to clarify the influence from the terrain on the ratio...

  17. CCS site characterisation criteria

    Energy Technology Data Exchange (ETDEWEB)

    Bachu, S.; Hawkes, C.; Lawton, D.; Pooladi-Darvish, M.; Perkins, E.

    2009-12-15

    IEA GHG recently commissioned the Alberta Research Counil in Canada to conduct a review of storage site selection criteria and site characterisation methods in order to produce a synthesis report. This report reviews the literature on the subject on the site seleciton and characterisation since the publication of the IPCC Special Report on CCS, and provides a synthesis and classification of criteria. 161 refs.

  18. 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.)

  19. Site Environmental Report, 1993

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-01

    The Site Environmental Report (SER) is prepared annually in accordance with DOE Order 5400.1, ``General Environmental Protection Program.`` This 1993 SER provides the general public as well as scientists and engineers with the results from the site`s ongoing Environmental Monitoring Program. Also included in this report is information concerning the site`s progress toward achieving full compliance with requirements set forth by DOE, US Environmental Protection Agency (USEPA), and Ohio EPA (OEPA). For some readers, the highlights provided in the Executive Summary may provide sufficient information. Many readers, however, may wish to read more detailed descriptions of the information than those which are presented here.

  20. Olkiluoto site description 2011

    International Nuclear Information System (INIS)

    2012-12-01

    This fourth version of the Olkiluoto Site Report, produced by the OMTF (Olkiluoto Modelling Task Force), updates the Olkiluoto Site Report 2008 with the data and knowledge obtained up to December 2010. A descriptive model of the site (the Site Descriptive Model, SDM), i.e. a model describing the geological and hydrogeological structure of the site, properties of the bedrock and the groundwater and its flow, and the associated interacting processes and mechanisms. The SDM is divided into six parts: surface system, geology, rock mechanics, hydrogeology, hydrogeochemistry and transport properties

  1. Olkiluoto site description 2011

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-12-15

    This fourth version of the Olkiluoto Site Report, produced by the OMTF (Olkiluoto Modelling Task Force), updates the Olkiluoto Site Report 2008 with the data and knowledge obtained up to December 2010. A descriptive model of the site (the Site Descriptive Model, SDM), i.e. a model describing the geological and hydrogeological structure of the site, properties of the bedrock and the groundwater and its flow, and the associated interacting processes and mechanisms. The SDM is divided into six parts: surface system, geology, rock mechanics, hydrogeology, hydrogeochemistry and transport properties.

  2. Hanford Site Infrastructure Plan

    International Nuclear Information System (INIS)

    1990-01-01

    The Hanford Site Infrastructure Plan (HIP) has been prepared as an overview of the facilities, utilities, systems, and services that support all activities on the Hanford Site. Its purpose is three-fold: to examine in detail the existing condition of the Hanford Site's aging utility systems, transportation systems, Site services and general-purpose facilities; to evaluate the ability of these systems to meet present and forecasted Site missions; to identify maintenance and upgrade projects necessary to ensure continued safe and cost-effective support to Hanford Site programs well into the twenty-first century. The HIP is intended to be a dynamic document that will be updated accordingly as Site activities, conditions, and requirements change. 35 figs., 25 tabs

  3. Hanford Site Development Plan

    International Nuclear Information System (INIS)

    Hathaway, H.B.; Daly, K.S.; Rinne, C.A.; Seiler, S.W.

    1992-05-01

    The Hanford Site Development Plan (HSDP) provides an overview of land use, infrastructure, and facility requirements to support US Department of Energy (DOE) programs at the Hanford Site. The HSDP's primary purpose is to inform senior managers and interested parties of development activities and issues that require a commitment of resources to support the Hanford Site. The HSDP provides a land use plan for the Hanford Site and presents a picture of what is currently known and anticipated in accordance with DOE Order 4320.1B. Site Development Planning. The HSDP wig be updated annually as future decisions further shape the mission and overall site development process. Further details about Hanford Site development are defined in individual area development plans

  4. Position of the third Na+ site in the aspartate transporter GltPh and the human glutamate transporter, EAAT1.

    Directory of Open Access Journals (Sweden)

    Turgut Bastug

    Full Text Available Glutamate transport via the human excitatory amino acid transporters is coupled to the co-transport of three Na(+ ions, one H(+ and the counter-transport of one K(+ ion. Transport by an archaeal homologue of the human glutamate transporters, Glt(Ph, whose three dimensional structure is known is also coupled to three Na(+ ions but only two Na(+ ion binding sites have been observed in the crystal structure of Glt(Ph. In order to fully utilize the Glt(Ph structure in functional studies of the human glutamate transporters, it is essential to understand the transport mechanism of Glt(Ph and accurately determine the number and location of Na(+ ions coupled to transport. Several sites have been proposed for the binding of a third Na(+ ion from electrostatic calculations and molecular dynamics simulations. In this study, we have performed detailed free energy simulations for Glt(Ph and reveal a new site for the third Na(+ ion involving the side chains of Threonine 92, Serine 93, Asparagine 310, Aspartate 312, and the backbone of Tyrosine 89. We have also studied the transport properties of alanine mutants of the coordinating residues Threonine 92 and Serine 93 in Glt(Ph, and the corresponding residues in a human glutamate transporter, EAAT1. The mutant transporters have reduced affinity for Na(+ compared to their wild type counterparts. These results confirm that Threonine 92 and Serine 93 are involved in the coordination of the third Na(+ ion in Glt(Ph and EAAT1.

  5. A catalytic metal ion interacts with the cleavage site G•U wobble in the HDV ribozyme†

    Science.gov (United States)

    Chen, Jui-Hui; Gong, Bo; Bevilacqua, Philip C.; Carey, Paul R.; Golden, Barbara L.

    2009-01-01

    The HDV ribozyme self-cleaves by a chemical mechanism involving general acid-base catalysis to generate a 2′,3′-cyclic phosphate and a 5′-hydroxyl termini. Biochemical studies from several laboratories have implicated C75 as the general acid and hydrated magnesium as the general base. We have previously shown that C75 has a pKa shifted > 2 pH units toward neutrality [Gong, B., Chen, J. H., Chase, E., Chadalavada, D. M., Yajima, R., Golden, B. L., Bevilacqua, P. C., and Carey, P. R. (2007) J. Am. Chem. Soc. 129, 13335–13342.], while in crystal structures, it is well-positioned for proton transfer. However no crystallographic evidence for a hydrated magnesium poised to serve as a general base in the reaction has been observed in high-resolution crystal structures of various reaction states and mutants. Herein, we use solution kinetic experiments and parallel Raman crystallographic studies to examine the effects of pH on rate and Mg2+-binding properties of wild-type and 7-deazaguanosine mutants of the HDV ribozyme. These data suggest that a previously-unobserved hydrated magnesium ion interacts with the N7 of the cleavage site G•U wobble base pair. Integrating this metal ion binding site with the available crystal structures provides a new three-dimensional model for the active site of the ribozyme that accommodates all available biochemical data and appears competent for catalysis. The position of this metal is consistent with a role of a magnesium-bound hydroxide as a general base as dictated by biochemical data. PMID:19178151

  6. 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.

  7. Site characterization plan:

    International Nuclear Information System (INIS)

    1988-01-01

    The Yucca Mountain site in Nevada is one of three candidate sites for the first geologic repository for radioactive waste. On May 28, 1986, it was recommended for detailed study in a program of site characterization. This site characterization plan (SCP) has been prepared in accordance with the requirements of the Nuclear Waste Policy Act to summarize the information collected to date about the geologic conditions at the site;to describe the conceptual designs for the repository and the waste package;and to present the plans for obtaining the geologic information necessary to demonstrate the suitability of the site for repository, to design the repository and the waste package, to prepare an environmental impact statement, and to obtain from the US Nuclear Regulatory Commission (NRC) an authorization to construct the repository. This introduction begins with a brief section on the process for siting and developing a repository, followed by a discussion of the pertinent legislation and regulations. A description of site characterization is presented next;it describes the facilities to be constructed for the site characterization program and explains the principal activities to be conducted during the program. Finally, the purpose, content, organizing principles, and organization of this site characterization plan are outlined, and compliance with applicable regulations is discussed

  8. Site characterization plan:

    International Nuclear Information System (INIS)

    1988-01-01

    The Yucca Mountain site in Nevada is one of three candidate sites for the first geologic repository for radioactive waste. On May 28, 1986, it was recommended for detailed study in a program of site characterization. This site characterization plan (SCP) has been prepared in acordance with the requirements of the Nuclear Waste Policy Act to summarize the information collected to date about the geologic conditions at the site;to describe the conceptual designs for the repository and the waste package and to present the plans for obtaining the geologic information necessary to demonstrate the suitability of the site for a repository, to design the repository and the waste package, to prepare an environmental impact statement, and to obtain from the US Nuclear Regulatory Commission (NRC) an authorization to construct the repository. This introduction begins with a brief section on the process for siting and eveloping a repository, followed by a discussion of the pertinent legislation and regulations. A description of site characterization is presented next;it describes the facilities to be constructed for the site characterization program and explains the principal activities to be conducted during the program. Finally, the purpose, content, organizing prinicples, and organization of this site characterization plan are outlined, and compliance with applicable regulations is discussed. 880 refs., 130 figs., 25 tabs

  9. CERN single sign on solution

    International Nuclear Information System (INIS)

    Ormancey, E

    2008-01-01

    The need for Single Sign On has always been restricted by the absence of cross platform solutions: a single sign on working only on one platform or technology is nearly useless. The recent improvements in Web Services Federation (WS-Federation) standard enabling federation of identity, attribute, authentication and authorization information can now provide real extended Single Sign On solutions. Various solutions have been investigated at CERN and now, a Web SSO solution using some parts of WS-Federation technology is available. Using the Shibboleth Service Provider module for Apache hosted web sites and Microsoft ADFS as the identity provider linked to Active Directory user, users can now authenticate on any web application using a single authentication platform, providing identity, user information (building, phone...) as well as group membership enabling authorization possibilities. A typical scenario: a CERN user can now authenticate on a Linux/Apache website using Windows Integrated credentials, and his Active Directory group membership can be checked before allowing access to a specific web page

  10. Site environmental programs

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, J.W.; Hanf, R.W.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the site environmental programs. Effluent monitoring and environmental surveillance programs monitor for impacts from operations in several areas. The first area consists of the point of possible release into the environment. The second area consists of possible contamination adjacent to DOE facilities, and the third area is the general environment both on and off the site.

  11. Site environmental report summary

    International Nuclear Information System (INIS)

    1992-01-01

    In this summary of the Fernald 1992 Site Environmental Report the authors will describe the impact of the Fernald site on man and the environment and provide results from the ongoing Environmental Monitoring Program. Also included is a summary of the data obtained from sampling conducted to determine if the site complies with DOE, US Environmental Protection Agency (USEPA), and Ohio EPA (OEPA) requirements. These requirements are set to protect both man and the environment

  12. Site environmental programs

    International Nuclear Information System (INIS)

    Schmidt, J.W.; Hanf, R.W.

    1995-01-01

    This section of the 1994 Hanford Site Environmental Report summarizes the site environmental programs. Effluent monitoring and environmental surveillance programs monitor for impacts from operations in several areas. The first area consists of the point of possible release into the environment. The second area consists of possible contamination adjacent to DOE facilities, and the third area is the general environment both on and off the site

  13. CERCLA site assessment workbook

    International Nuclear Information System (INIS)

    1994-08-01

    This contains comments for each chapter of exercises (in Vol. 1) which illustrate how to conduct site assessments for CERCLA regulation. A through analysis of the exercises is provided so that work and solutions from Vol 1 can be critiqued and comments are also included on the strategy of site assessment whereas the exercises illustrate the principles involved. Covered exercises include the following: A preliminary assessment of a ground water site; waste characteristics and characterization of sources; documentation of observed releases and actual contamination of targets; the strategy of an SI at a surface water site; the soil exposure pathway; the air pathway

  14. 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

  15. Meteorology in site operations

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    During the site selection and design phases of a plant, meteorological assistance must be based on past records, usually accumulated at stations not actually on the site. These preliminary atadvices will be averages and extremes that might be expected. After a location has been chosen and work has begun, current and forecast weather conditions become of immediate concern. On-site meteorological observations and forecasts have many applications to the operating program of an atomic energy site. Requirements may range from observations of the daily minimum temperatures to forecasts of radiation dosages from airborne clouds

  16. 1994 Site environmental report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The Fernald site is a Department of Energy (DOE)-owned facility that produced high-quality uranium metals for military defense for nearly 40 years. DOE suspended production at the site in 1989 and formally ended production in 1991. Although production activities have ceased, the site continues to examine the air and liquid pathways as possible routes through which pollutants from past operations and current remedial activities may leave the site. The Site Environmental Report (SER) is prepared annually in accordance with DOE Order 5400.1, General Environmental Protection Program. This 1994 SER provides the general public as well as scientists and engineers with the results from the site`s ongoing Environmental Monitoring Program. Also included in this report is information concerning the site`s progress toward achieving full compliance with requirements set forth by DOE, U.S. Environmental Protection Agency (USEPA), and Ohio EPA (OEPA). For some readers, the highlights provided in this Executive Summary may provide sufficient information. Many readers, however, may wish to read more detailed descriptions of the information than those which are presented here. All information presented in this summary is discussed more fully in the main body of this report.

  17. Single Audit: Single Audit Act Effectiveness Issues

    National Research Council Canada - National Science Library

    Thompson, Sally

    2002-01-01

    As discussed in the report we are releasing today, our work to review agency actions to ensure that recipients take timely and appropriate corrective actions to fix audit findings contained in single...

  18. Savannah River Site's Site Specific Plan

    International Nuclear Information System (INIS)

    1991-01-01

    This Site Specific Plan (SSP) has been prepared by the Savannah River Site (SRS) in order to show the Environmental Restoration and Waste Management activities that were identified during the preparation of the Department of Energy-Headquarters (DOE-HQ) Environmental Restoration and Waste Management Five-Year Plan (FYP) for FY 1992--1996. The SSP has been prepared in accordance with guidance received from DOE-HQ. DOE-SR is accountable to DOE-HQ for the implementation of this plan. The purpose of the SSP is to develop a baseline for policy, budget, and schedules for the DOE Environmental Restoration and Waste Management activities. The plan explains accomplishments since the Fiscal Year (FY) 1990 plan, demonstrates how present and future activities are prioritized, identifies currently funded activities and activities that are planned to be funded in the upcoming fiscal year, and describes future activities that SRS is considering

  19. SITE-94. Mineralogy of the Aespoe site

    International Nuclear Information System (INIS)

    Andersson, Karin

    1996-12-01

    The water composition has several impacts on the repository. It will influence the behaviour of the engineered materials (e.g. corrosion). It may also determine the possible solubility and speciation of released radionuclides. It also acts as a transport medium for the released elements. The groundwater composition and the potential development of the composition due to the presence of the repository as well as due to external variations is thus an important issue in a safety analysis. The development of the groundwater composition is strongly dependent on reactions with the minerals present in water bearing fractures. Here equilibrium chemistry may be of importance, but also reaction kinetics is important to the long-term behaviour. Within the SITE-94 project, a safety analysis is performed for the conditions at the Aespoe site. The mineralogy of the area has been evaluated from drill cores at various places at the site. In this report a recommendation for selection of mineralogy to be used in geochemical modelling of the repository is given. Calcite and iron containing minerals dominate the fracture filling mineralogy at the Aespoe site. Some typical fracture filling mineralogies may be identified in the fractures: epidote, chlorite, calcite, hematite, some illite/smectite + quartz, fluorite, pyrite and goethite. In addition to these a number of minor minerals are found in the fractures. Uncertainties in the fracture filling data may be due to problems when taking out the drill cores. Drilling water may remove important clay minerals and sealed fractures may be reopened mechanically and treated as water conducting fractures. The problem of determining the variability of the mineralogy along the flow paths also remains. This problem will never be solved when the investigation is performed by drilling investigation holes

  20. Preliminary Site Characterization Report, Rulsion Site, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    This report is a summary of environmental information gathered during a review of the documents pertaining to Project Rulison and interviews with personnel who worked on the project. Project Rulison was part of Operation Plowshare (a program designed to explore peaceful uses for nuclear devices). The project consisted of detonating a 43-kiloton nuclear device on September 10, 1969, in western Colorado to stimulate natural gas production. Following the detonation, a reentry well was drilled and several gas production tests were conducted. The reentry well was shut-in after the last gas production test and was held in standby condition until the general cleanup was undertaken in 1972. A final cleanup was conducted after the emplacement and testing wells were plugged in 1976. However, some surface radiologic contamination resulted from decontamination of the drilling equipment and fallout from the gas flaring during drilling operations. With the exception of the drilling effluent pond, all surface contamination at the Rulison Site was removed during the cleanup operations. All mudpits and other excavations were backfilled, and both upper and lower drilling pads were leveled and dressed. This report provides information regarding known or suspected areas of contamination, previous cleanup activities, analytical results, a review of the regulatory status, the site`s physical environment, and future recommendations for Project Ruhson. Based on this research, several potential areas of contamination have been identified. These include the drilling effluent pond and mudpits used during drilling operations. In addition, contamination could migrate in the gas horizon.

  1. A structurally based analytic model of growth and biomass dynamics in single species stands of conifers

    Science.gov (United States)

    Robin J. Tausch

    2015-01-01

    A theoretically based analytic model of plant growth in single species conifer communities based on the species fully occupying a site and fully using the site resources is introduced. Model derivations result in a single equation simultaneously describes changes over both, different site conditions (or resources available), and over time for each variable for each...

  2. Site-Specific Innovation

    DEFF Research Database (Denmark)

    Reeh, Henrik; Hemmersam, Peter

    2015-01-01

    Currently, cities across the Northern European region are actively redeveloping their former industrial harbours. Indeed, harbours areas are essential in the long-term transition from industrial to information and experience societies; harbours are becoming sites for new businesses and residences...... question is how innovation may contribute to urban life and site-specific qualities....

  3. Criminal Justice Web Sites.

    Science.gov (United States)

    Dodge, Timothy

    1998-01-01

    Evaluates 15 criminal justice Web sites that have been selected according to the following criteria: authority, currency, purpose, objectivity, and potential usefulness to researchers. The sites provide narrative and statistical information concerning crime, law enforcement, the judicial system, and corrections. Searching techniques are also…

  4. The site selection process

    International Nuclear Information System (INIS)

    Kittel, J.H.

    1989-01-01

    One of the most arduous tasks associated with the management of radioactive wastes is the siting of new disposal facilities. Experience has shown that the performance of the disposal facility during and after disposal operations is critically dependent on the characteristics of the site itself. The site selection process consists of defining needs and objectives, identifying geographic regions of interest, screening and selecting candidate sites, collecting data on the candidate sites, and finally selecting the preferred site. Before the site selection procedures can be implemented, however, a formal legal system must be in place that defines broad objectives and, most importantly, clearly establishes responsibilities and accompanying authorities for the decision-making steps in the procedure. Site selection authorities should make every effort to develop trust and credibility with the public, local officials, and the news media. The responsibilities of supporting agencies must also be spelled out. Finally, a stable funding arrangement must be established so that activities such as data collection can proceed without interruption. Several examples, both international and within the US, are given

  5. Siting nuclear power plants

    International Nuclear Information System (INIS)

    Yellin, J.; Joskow, P.L.

    1980-01-01

    The first edition of this journal is devoted to the policies and problems of siting nuclear power plants and the question of how far commercial reactors should be placed from urban areas. The article is divided into four major siting issues: policies, risk evaluation, accident consequences, and economic and physical constraints. One concern is how to treat currently operating reactors and those under construction that were established under less-stringent criteria if siting is to be used as a way to limit the consequences of accidents. Mehanical cost-benefit analyses are not as appropriate as the systematic use of empirical observations in assessing the values involved. Stricter siting rules are justified because (1) opposition because of safety is growing: (2) remote siting will make the industry more stable; (3) the conflict is eliminated between regulatory policies and the probability basis for nuclear insurance; and (4) joint ownership of utilities and power-pooling are increasing. 227 references, 7 tables

  6. Site decommissioning management plan

    International Nuclear Information System (INIS)

    Fauver, D.N.; Austin, J.H.; Johnson, T.C.; Weber, M.F.; Cardile, F.P.; Martin, D.E.; Caniano, R.J.; Kinneman, J.D.

    1993-10-01

    The Nuclear Regulatory Commission (NRC) staff has identified 48 sites contaminated with radioactive material that require special attention to ensure timely decommissioning. While none of these sites represent an immediate threat to public health and safety they have contamination that exceeds existing NRC criteria for unrestricted use. All of these sites require some degree of remediation, and several involve regulatory issues that must be addressed by the Commission before they can be released for unrestricted use and the applicable licenses terminated. This report contains the NRC staff's strategy for addressing the technical, legal, and policy issues affecting the timely decommissioning of the 48 sites and describes the status of decommissioning activities at the sites

  7. Site decommissioning management plan

    Energy Technology Data Exchange (ETDEWEB)

    Fauver, D.N.; Austin, J.H.; Johnson, T.C.; Weber, M.F.; Cardile, F.P.; Martin, D.E.; Caniano, R.J.; Kinneman, J.D.

    1993-10-01

    The Nuclear Regulatory Commission (NRC) staff has identified 48 sites contaminated with radioactive material that require special attention to ensure timely decommissioning. While none of these sites represent an immediate threat to public health and safety they have contamination that exceeds existing NRC criteria for unrestricted use. All of these sites require some degree of remediation, and several involve regulatory issues that must be addressed by the Commission before they can be released for unrestricted use and the applicable licenses terminated. This report contains the NRC staff`s strategy for addressing the technical, legal, and policy issues affecting the timely decommissioning of the 48 sites and describes the status of decommissioning activities at the sites.

  8. Single-Sex Classrooms

    Science.gov (United States)

    Protheroe, Nancy

    2009-01-01

    Although single-sex education was once the norm in the U.S., the practice has largely been confined to private schools for more than a century. However, with the introduction of the final version of the U.S. Department of Education's so-called single-sex regulations in 2006, public schools were allowed greater flexibility to offer single-sex…

  9. Superconducting Single Photon Detectors

    NARCIS (Netherlands)

    Dorenbos, S.N.

    2011-01-01

    This thesis is about the development of a detector for single photons, particles of light. New techniques are being developed that require high performance single photon detection, such as quantum cryptography, single molecule detection, optical radar, ballistic imaging, circuit testing and

  10. Single frequency intracavity SRO

    DEFF Research Database (Denmark)

    Abitan, Haim; Buchhave, Preben

    2000-01-01

    Summary form only given. A single resonance optical parametric oscillator (SRO) is inserted intracavity to a CW high power, single frequency, and ring Nd:YVO4 laser. We obtain a stable single frequency CW SRO with output at 1.7-1.9 μm (idler) and a resonating signal at 2.3-2.6 μm. The behavior...

  11. Activities on the site during construction phase

    International Nuclear Information System (INIS)

    Fickel, O.F.

    1977-01-01

    A survey is given of the work done on the site from site-opening till turn over of the plant to the client. After a short introduction to time schedules, manpower on site, site facilities and civil work and constructions, the commissioning and trial operation phase is discussed in detail. This phase begins with finishing the assembly of individual systems and components and ends with the trial operation and the acceptance measurement. During this period the subsystems are started-up in a useful sequence, first from cold, then from hot conditions and are finally operated as a total with nuclear energy. The single steps are: a) commissioning of indivudal systems; b) hot functional test 1 (without fuels) c) baseline inspection at the reactor pressure vessel; d) hot functional test 2 (with fuels); e) preparation for first criticality; f) postcriticality test program; g) trial operation: h) acceptance measurement. (HP) [de

  12. SiteFind: A software tool for introducing a restriction site as a marker for successful site-directed mutagenesis

    Directory of Open Access Journals (Sweden)

    Evans Paul M

    2005-12-01

    Full Text Available Abstract Background Site-directed mutagenesis is a widely-used technique for introducing mutations into a particular DNA sequence, often with the goal of creating a point mutation in the corresponding amino acid sequence but otherwise leaving the overall sequence undisturbed. However, this method provides no means for verifying its success other than sequencing the putative mutant construct: This can quickly become an expensive method for screening for successful mutations. An alternative to sequencing is to simultaneously introduce a restriction site near the point mutation in manner such that the restriction site has no effect on the translated amino acid sequence. Thus, the novel restriction site can be used as a marker for successful mutation which can be quickly and easily assessed. However, finding a restriction site that does not disturb the corresponding amino acid sequence is a time-consuming task even for experienced researchers. A fast and easy to use computer program is needed for this task. Results We wrote a computer program, called SiteFind, to help us design a restriction site within the mutation primers without changing the peptide sequence. Because of the redundancy of genetic code, a given peptide can be encoded by many different DNA sequences. Since the list of possible restriction sites for a given DNA sequence is not always obvious, SiteFind automates this task. The number of possible sequences a computer program must search through increases exponentially as the sequence length increases. SiteFind uses a novel "moving window" algorithm to reduce the number of possible sequences to be searched to a manageable level. The user enters a nucleotide sequence, specifies what amino acid residues should be changed in the mutation, and SiteFind generates a list of possible restriction sites and what nucleotides must be changed to introduce that site. As a demonstration of its use, we successfully generated a single point mutation

  13. SINGLE HEATER TEST FINAL REPORT

    Energy Technology Data Exchange (ETDEWEB)

    J.B. Cho

    1999-05-01

    The Single Heater Test is the first of the in-situ thermal tests conducted by the U.S. Department of Energy as part of its program of characterizing Yucca Mountain in Nevada as the potential site for a proposed deep geologic repository for the disposal of spent nuclear fuel and high-level nuclear waste. The Site Characterization Plan (DOE 1988) contained an extensive plan of in-situ thermal tests aimed at understanding specific aspects of the response of the local rock-mass around the potential repository to the heat from the radioactive decay of the emplaced waste. With the refocusing of the Site Characterization Plan by the ''Civilian Radioactive Waste Management Program Plan'' (DOE 1994), a consolidated thermal testing program emerged by 1995 as documented in the reports ''In-Situ Thermal Testing Program Strategy'' (DOE 1995) and ''Updated In-Situ Thermal Testing Program Strategy'' (CRWMS M&O 1997a). The concept of the Single Heater Test took shape in the summer of 1995 and detailed planning and design of the test started with the beginning fiscal year 1996. The overall objective of the Single Heater Test was to gain an understanding of the coupled thermal, mechanical, hydrological, and chemical processes that are anticipated to occur in the local rock-mass in the potential repository as a result of heat from radioactive decay of the emplaced waste. This included making a priori predictions of the test results using existing models and subsequently refining or modifying the models, on the basis of comparative and interpretive analyses of the measurements and predictions. A second, no less important, objective was to try out, in a full-scale field setting, the various instruments and equipment to be employed in the future on a much larger, more complex, thermal test of longer duration, such as the Drift Scale Test. This ''shake down'' or trial aspect of the Single Heater Test applied

  14. SINGLE HEATER TEST FINAL REPORT

    International Nuclear Information System (INIS)

    J.B. Cho

    1999-01-01

    The Single Heater Test is the first of the in-situ thermal tests conducted by the U.S. Department of Energy as part of its program of characterizing Yucca Mountain in Nevada as the potential site for a proposed deep geologic repository for the disposal of spent nuclear fuel and high-level nuclear waste. The Site Characterization Plan (DOE 1988) contained an extensive plan of in-situ thermal tests aimed at understanding specific aspects of the response of the local rock-mass around the potential repository to the heat from the radioactive decay of the emplaced waste. With the refocusing of the Site Characterization Plan by the ''Civilian Radioactive Waste Management Program Plan'' (DOE 1994), a consolidated thermal testing program emerged by 1995 as documented in the reports ''In-Situ Thermal Testing Program Strategy'' (DOE 1995) and ''Updated In-Situ Thermal Testing Program Strategy'' (CRWMS M and O 1997a). The concept of the Single Heater Test took shape in the summer of 1995 and detailed planning and design of the test started with the beginning fiscal year 1996. The overall objective of the Single Heater Test was to gain an understanding of the coupled thermal, mechanical, hydrological, and chemical processes that are anticipated to occur in the local rock-mass in the potential repository as a result of heat from radioactive decay of the emplaced waste. This included making a priori predictions of the test results using existing models and subsequently refining or modifying the models, on the basis of comparative and interpretive analyses of the measurements and predictions. A second, no less important, objective was to try out, in a full-scale field setting, the various instruments and equipment to be employed in the future on a much larger, more complex, thermal test of longer duration, such as the Drift Scale Test. This ''shake down'' or trial aspect of the Single Heater Test applied not just to the hardware, but also to the teamwork and cooperation between

  15. Single atom oscillations

    International Nuclear Information System (INIS)

    Wiorkowski, P.; Walther, H.

    1990-01-01

    Modern methods of laser spectroscopy allow the study of single atoms or ions in an unperturbed environment. This has opened up interesting new experiments, among them the detailed study of radiation-atom coupling. In this paper, the following two experiments dealing with this problem are reviewed: the single-atom maser and the study of the resonance fluorescence of a single stored ion. The simplest and most fundamental system for studying radiation-matter coupling is a single two-level atom interacting with a single mode of an electromagnetic field in a cavity. This problem received a great deal of attention shortly after the maser was invented

  16. 1994 Site environmental report

    International Nuclear Information System (INIS)

    1995-07-01

    The Fernald site is a Department of Energy (DOE)-owned facility that produced high-quality uranium metals for military defense for nearly 40 years. DOE suspended production at the site in 1989 and formally ended production in 1991. Although production activities have ceased, the site continues to examine the air and liquid pathways as possible routes through which pollutants from past operations and current remedial activities may leave the site. The Site Environmental Report (SER) is prepared annually in accordance with DOE Order 5400.1, General Environmental Protection Program. This 1994 SER provides the general public as well as scientists and engineers with the results from the site's ongoing Environmental Monitoring Program. Also included in this report is information concerning the site's progress toward achieving full compliance with requirements set forth by DOE, U.S. Environmental Protection Agency (USEPA), and Ohio EPA (OEPA). For some readers, the highlights provided in this Executive Summary may provide sufficient information. Many readers, however, may wish to read more detailed descriptions of the information than those which are presented here. All information presented in this summary is discussed more fully in the main body of this report

  17. SITE-94. Radionuclide solubilities for SITE-94

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, R.; Apted, M. [QuantiSci, Denver, CO (United States)

    1996-12-01

    In this report, solubility constraints are evaluated on radioelement source-term concentrations supporting the SITE-94 performance assessment. Solubility models are based on heterogeneous-equilibrium, mass- and charge-balance constraints incorporated into the EQ3/6 geochemical software package, which is used to calculate the aqueous speciation behavior and solubilities of U, Th, Pu, Np, Am, Ni, Ra, Se, Sn, Sr, Tc and Zr in site groundwaters and near-field solutions. The chemical evolution of the near field is approximated using EQ3/6 in terms of limiting conditions at equilibrium, or steady state, in three closed systems representing fully saturated bentonite, Fe{sup o} corrosion products of the canister, and spent fuel. The calculations consider both low-temperature (15 deg C) and high-temperature (80 deg C) conditions in the near field, and the existence of either reducing or strongly oxidizing conditions in each of the bentonite, canister, and spent-fuel barriers. Heterogeneities in site characteristics are evaluated through consideration of a range of initial groundwaters and their interactions with engineered barriers. Aqueous speciation models for many radioelements are constrained by thermodynamic data that are estimated with varying degrees of accuracy. An important question, however, is how accurate do these models need to be for purposes of estimating source-term concentrations? For example, it is unrealistic to expect a high degree of accuracy in speciation models if such models predict solubilities that are below the analytical detection limit for a given radioelement. From a practical standpoint, such models are irrelevant if calculated solubilities cannot be tested by direct comparison to experimental data. In the absence of models that are both accurate and relevant for conditions of interest, the detection limit could define a pragmatic upper limit on radioelement solubility 56 refs, 25 tabs, 10 figs

  18. SITE-94. Radionuclide solubilities for SITE-94

    International Nuclear Information System (INIS)

    Arthur, R.; Apted, M.

    1996-12-01

    In this report, solubility constraints are evaluated on radioelement source-term concentrations supporting the SITE-94 performance assessment. Solubility models are based on heterogeneous-equilibrium, mass- and charge-balance constraints incorporated into the EQ3/6 geochemical software package, which is used to calculate the aqueous speciation behavior and solubilities of U, Th, Pu, Np, Am, Ni, Ra, Se, Sn, Sr, Tc and Zr in site groundwaters and near-field solutions. The chemical evolution of the near field is approximated using EQ3/6 in terms of limiting conditions at equilibrium, or steady state, in three closed systems representing fully saturated bentonite, Fe o corrosion products of the canister, and spent fuel. The calculations consider both low-temperature (15 deg C) and high-temperature (80 deg C) conditions in the near field, and the existence of either reducing or strongly oxidizing conditions in each of the bentonite, canister, and spent-fuel barriers. Heterogeneities in site characteristics are evaluated through consideration of a range of initial groundwaters and their interactions with engineered barriers. Aqueous speciation models for many radioelements are constrained by thermodynamic data that are estimated with varying degrees of accuracy. An important question, however, is how accurate do these models need to be for purposes of estimating source-term concentrations? For example, it is unrealistic to expect a high degree of accuracy in speciation models if such models predict solubilities that are below the analytical detection limit for a given radioelement. From a practical standpoint, such models are irrelevant if calculated solubilities cannot be tested by direct comparison to experimental data. In the absence of models that are both accurate and relevant for conditions of interest, the detection limit could define a pragmatic upper limit on radioelement solubility

  19. AMCO Off-Site Air Monitoring Polygons, Oakland CA, 2017, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — This feature class was developed to support the AMCO Chemical Superfund Site air monitoring process and depicts a single polygon layer, Off-Site Air Monitors,...

  20. LBA-ECO CD-10 Temperature Profiles at km 67 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a single text file which reports temperature measurements at the Para Western (Santarem) - km 67, Primary Forest Tower Site. This site is in...

  1. Site Environmental Report, 1993

    International Nuclear Information System (INIS)

    1994-06-01

    The Site Environmental Report (SER) is prepared annually in accordance with DOE Order 5400.1, ''General Environmental Protection Program.'' This 1993 SER provides the general public as well as scientists and engineers with the results from the site's ongoing Environmental Monitoring Program. Also included in this report is information concerning the site's progress toward achieving full compliance with requirements set forth by DOE, US Environmental Protection Agency (USEPA), and Ohio EPA (OEPA). For some readers, the highlights provided in the Executive Summary may provide sufficient information. Many readers, however, may wish to read more detailed descriptions of the information than those which are presented here

  2. Savannah River Site environmental report for 1993

    International Nuclear Information System (INIS)

    Arnett, M.W.; Karapatakis, L.K.; Mamatey, A.R.

    1994-01-01

    Savannah River Site (SRS) conducts effluent monitoring and environmental surveillance to ensure the safety of the public and the well-being of the environment. DOE Order 5400,1, ''General Environmental Protection Program,'' requires the submission of an environmental report that documents the impact of facility operations on the environment and on public health. SRS has had an extensive environmental surveillance program in place since 1951 (before site startup). At that time, data generated by the on-site surveillance program were reported in site documents. Beginning in 1959, data from off-site environmental monitoring activities were presented in reports issued for public dissemination. Separate reporting of SRS's on- and off-site environmental monitoring activities continued until 1985, when data from both surveillance programs were merged into a single public document. The Savannah River Site Environmental Report for 1993 is an overview of effluent monitoring and environmental surveillance activities conducted on and in the vicinity of SRS from January 1 through December 31, 1993. For complete program descriptions, consult the ''SRS Environmental Monitoring Plan'' (WSRC-3Ql-2-1000). It documents the rationale and design criteria for the monitoring program, the frequency of monitoring and analysis, the specific analytical and sampling procedures, and the quality assurance requirements

  3. Savannah River Site environmental report for 1993

    Energy Technology Data Exchange (ETDEWEB)

    Arnett, M.W.; Karapatakis, L.K.; Mamatey, A.R. [eds.

    1994-08-01

    Savannah River Site (SRS) conducts effluent monitoring and environmental surveillance to ensure the safety of the public and the well-being of the environment. DOE Order 5400,1, ``General Environmental Protection Program,`` requires the submission of an environmental report that documents the impact of facility operations on the environment and on public health. SRS has had an extensive environmental surveillance program in place since 1951 (before site startup). At that time, data generated by the on-site surveillance program were reported in site documents. Beginning in 1959, data from off-site environmental monitoring activities were presented in reports issued for public dissemination. Separate reporting of SRS`s on- and off-site environmental monitoring activities continued until 1985, when data from both surveillance programs were merged into a single public document. The Savannah River Site Environmental Report for 1993 is an overview of effluent monitoring and environmental surveillance activities conducted on and in the vicinity of SRS from January 1 through December 31, 1993. For complete program descriptions, consult the ``SRS Environmental Monitoring Plan`` (WSRC-3Ql-2-1000). It documents the rationale and design criteria for the monitoring program, the frequency of monitoring and analysis, the specific analytical and sampling procedures, and the quality assurance requirements.

  4. 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

  5. EPA FRS Facilities State Single File CSV Download

    Science.gov (United States)

    This page provides state comma separated value (CSV) files containing key information of all facilities and sites within the Facility Registry System (FRS). Each state zip file contains a single CSV file of key facility-level information.

  6. Retroviral integration: Site matters

    Science.gov (United States)

    Demeulemeester, Jonas; De Rijck, Jan

    2015-01-01

    Here, we review genomic target site selection during retroviral integration as a multistep process in which specific biases are introduced at each level. The first asymmetries are introduced when the virus takes a specific route into the nucleus. Next, by co‐opting distinct host cofactors, the integration machinery is guided to particular chromatin contexts. As the viral integrase captures a local target nucleosome, specific contacts introduce fine‐grained biases in the integration site distribution. In vivo, the established population of proviruses is subject to both positive and negative selection, thereby continuously reshaping the integration site distribution. By affecting stochastic proviral expression as well as the mutagenic potential of the virus, integration site choice may be an inherent part of the evolutionary strategies used by different retroviruses to maximise reproductive success. PMID:26293289

  7. Siting controversial facilities

    International Nuclear Information System (INIS)

    Baird, R.D.; Blacker, P.B.

    1985-01-01

    There is often significant difficulty involved with siting controversial facilities. The social and political problems are frequently far more difficult to resolve than the technical and economic issues. The tendancy for most developing organizations is to address only technical issues in the search for a technically optimal site, to the exclusion of such weighting considerations as the social and political climate associated with potential sites--an approach which often imperils the success of the project. The site selection processes currently suggested is summarized and two contemporary examples of their application are cited. The difference between developers' real objectives and the objectives they have implicitly assumed by adopting the recommended approaches without augmentation are noted. The resulting morass of public opposition is attributed to the failure to consider the needs of individuals and groups who stand to be negatively impacted by the development. A comprehensive implementation strategy which addresses non-technical consideration in parallel with technical ones is presented and evaluated

  8. Vatwa Resettlement Sites

    International Development Research Centre (IDRC) Digital Library (Canada)

    The BSUP sites, constructed under the Government of India's .... conflicts over paying for maintenance lead to unrepaired water and ... So some women reacted and broke things in the office." ... workplaces, leading many to drop out of work or.

  9. Safety aspects of siting

    International Nuclear Information System (INIS)

    Rosen, M.

    1976-01-01

    Outline of parameters to be considered in site selection, radiation safety, and mechanisms of radiation release. Radiation doses in tablular form for areas at various distances from the plant. (HP) [de

  10. Site Specific Vendor's License

    Data.gov (United States)

    Montgomery County of Maryland — This dataset contains information of a site-specific vendor's license which is required if an individual sells or offers to sell goods or services from a stationary...

  11. Surgical site infections

    African Journals Online (AJOL)

    Surgical site infections (SSIs) are a worldwide problem that has ... deep tissue is found on clinical examination, re-opening, histopathological or radiological investigation ..... Esposito S, Immune system and SSI, Journal of Chemotherapy, 2001.

  12. Superfund Site Information

    Data.gov (United States)

    U.S. Environmental Protection Agency — This asset includes a number of individual data sets related to site-specific information for Superfund, which is governed under the Comprehensive Environmental...

  13. Outdoor Recreation Sites Inventory

    Data.gov (United States)

    Vermont Center for Geographic Information — The RECSITES data layer contains a wide range of recreational sites in Vermont. This point data layer includes parks, ski areas, boat access points, and many other...

  14. Coal mine site reclamation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-02-15

    Coal mine sites can have significant effects on local environments. In addition to the physical disruption of land forms and ecosystems, mining can also leave behind a legacy of secondary detrimental effects due to leaching of acid and trace elements from discarded materials. This report looks at the remediation of both deep mine and opencast mine sites, covering reclamation methods, back-filling issues, drainage and restoration. Examples of national variations in the applicable legislation and in the definition of rehabilitation are compared. Ultimately, mine site rehabilitation should return sites to conditions where land forms, soils, hydrology, and flora and fauna are self-sustaining and compatible with surrounding land uses. Case studies are given to show what can be achieved and how some landscapes can actually be improved as a result of mining activity.

  15. Summer Meal Sites

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Information pertaining to Summer Meal Sites, as collected by Citiparks in the City of Pittsburgh Department of Parks and Recreation. This dataset includes the...

  16. Jet Car Track Site

    Data.gov (United States)

    Federal Laboratory Consortium — Located in Lakehurst, New Jersey, the Jet Car Track Site supports jet cars with J57 engines and has a maximum jet car thrust of 42,000 pounds with a maximum speed of...

  17. 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

  18. Fusion facility siting considerations

    International Nuclear Information System (INIS)

    Bussell, G.T.

    1985-01-01

    Inherent in the fusion program's transition from hydrogen devices to commercial power machines is a general increase in the size and scope of succeeding projects. This growth will lead to increased emphasis on safety, environmental impact, and the external effects of fusion in general, and of each new device in particular. A critically important consideration in this regard is site selection. The purpose of this paper is to examine major siting issues that may affect the economics, safety, and environmental impact of fusion

  19. Siting of research reactors

    International Nuclear Information System (INIS)

    1987-01-01

    The purpose of this document is to develop criteria for siting and the site-related design basis for research reactors. The concepts presented in this document are intended as recommendations for new reactors and are not suggested for backfitting purposes for facilities already in existence. In siting research reactors serious consideration is given to minimizing the effects of the site on the reactor and the reactor on the site and the potential impact of the reactor on the environment. In this document guidance is first provided on the evaluation of the radiological impact of the installation under normal reactor operation and accident conditions. A classification of research reactors in groups is then proposed, together with a different approach for each group, to take into account the relevant safety problems associated with facilities of different characteristics. Guidance is also provided for both extreme natural events and for man-induced external events which could affect the safe operation of the reactor. Extreme natural events include earthquakes, flooding for river or coastal sites and extreme meteorological phenomena. The feasibility of emergency planning is finally considered for each group of reactors

  20. pH-dependent kinetics of copper ions binding to amyloid-β peptide.

    Science.gov (United States)

    Bin, Yannan; Chen, Shu; Xiang, Juan

    2013-02-01

    Interactions of amyloid-β peptide (Aβ) with Cu(2+) are known to be pH-dependent and believed to play a crucial role in the neurotoxicity of Alzheimer's disease (AD). Some research has revealed that injured brains with lowered pH have higher risks of developing AD. However, reported experiments were performed under neutral or mildly acidic conditions, and no reports about the affinity of Aβ-Cu(2+) below pH6.0. In this study, surface plasmon resonance (SPR) sensor with immobilized Aβ was used to investigate the formation of Aβ-Cu(2+) complexes under acidic pH conditions. Dissociation constants were calculated and shown to be pH-dependent, ranging from 3.5×10(-8)M to 8.7×10(-3)M in the pH range from 7.0 to 4.0. The physiological significance of K(d) was preliminarily investigated by monitoring the generation of OH() in aerobic solutions containing Aβ-Cu(2+) and Cu(2+). The results imply that acidic conditions could aggravate the oxidative stress in the presence of Cu(2+), and the weak affinities of Aβ-Cu(2+) under mildly acidic pH of 5.0-6.0 could further enhance the oxidative damage. However, the oxidative stress effect of Aβ is negligible due to the suppressed formation of Aβ-Cu(2+) below pH5.0. This work is useful for the in-depth understanding of the role of Aβ-Cu(2+) in AD neuropathology. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

  1. Dansyl-naphthalimide dyads as molecular probes: effect of spacer group on metal ion binding properties.

    Science.gov (United States)

    Shankar, Balaraman H; Ramaiah, Danaboyina

    2011-11-17

    Interaction of a few dansyl-naphthalimide conjugates 1a-e linked through polymethylene spacer groups with various metal ions was investigated through absorption, fluorescence, NMR, isothermal calorimetric (ITC), and laser flash photolysis techniques. The characteristic feature of these dyads is that they exhibit competing singlet-singlet energy transfer (SSET) and photoinduced electron transfer (PET) processes, both of which decrease with the increase in spacer length. Depending on the spacer group, these dyads interact selectively with divalent Cu(2+) and Zn(2+) ions, as compared to other mono- and divalent metal ions. Jobs plot analysis showed that these dyads form 2:3 complexes with Cu(2+) ions, while 1:1 complexes were observed with Zn(2+) ions. The association constants for the Zn(2+) and Cu(2+) complexes were determined and are found to be in the order 10(3)-10(5) M(-1). Irrespective of the length of the spacer group, these dyads interestingly act as fluorescence ratiometric molecular probes for Cu(2+) ions by altering the emission intensity of both dansyl and naphthalimide chromophores. In contrast, only the fluorescence intensity of the naphthalimide chromophore of the lower homologues (n = 1-3) was altered by Zn(2+) ions. (1)H NMR and ITC measurements confirmed the involvement of both sulfonamide and dimethylamine groups in the complexation with Cu(2+) ions, while only the latter group was involved with Zn(2+) ions. Laser excitation of the dyads 1a-e showed formation of a transient absorption which can be attributed to the radical cation of the naphthalimide chromophore, whereas only the triplet excited state of the dyads 1a-e was observed in the presence of Cu(2+) ions. Uniquely, the complexation of 1a-e with Cu(2+) ions affects both PET and SSET processes, while only the PET process was partially inhibited by Zn(2+) ions in the lower homologues (n = 1-3) and the higher homologues exhibited negligible changes in their emission properties. Our results demonstrate that the spacer length dependent variations of the photophysical properties of these novel conjugates not only enable the selective detection of Cu(2+) and Zn(2+) ions but also aid in discriminating these two biologically important metal ions.

  2. Coupled ion binding and structural transitions along the transport cycle of glutamate transporters

    OpenAIRE

    Verdon, Grégory; Oh, SeCheol; Serio, Ryan N; Boudker, Olga

    2014-01-01

    eLife digest Molecules of glutamate can carry messages between cells in the brain, and these signals are essential for thought and memory. Glutamate molecules can also act as signals to build new connections between brain cells and to prune away unnecessary ones. However, too much glutamate outside of the cells kills the brain tissue and can lead to devastating brain diseases. In a healthy brain, special pumps called glutamate transporters move these molecules back into the brain cells, where...

  3. Single-Phase PLLs

    DEFF Research Database (Denmark)

    Golestan, Saeed; Guerrero, Josep M.; Quintero, Juan Carlos Vasquez

    2017-01-01

    Single-phase phase-locked loops (PLLs) are popular for the synchronization and control of single-phase gridconnected converters. They are also widely used for monitoring and diagnostic purposes in the power and energy areas. In recent years, a large number of single-phase PLLs with different stru......-PLLs). The members of each category are then described and their pros and cons are discussed. This work provides a deep insight into characteristics of different single-phase PLLs and, therefore, can be considered as a reference for researchers and engineers....

  4. Single ventricle cardiac defect

    International Nuclear Information System (INIS)

    Eren, B.; Turkmen, N.; Fedakar, R.; Cetin, V.

    2010-01-01

    Single ventricle heart is defined as a rare cardiac abnormality with a single ventricle chamber involving diverse functional and physiological defects. Our case is of a ten month-old baby boy who died shortly after admission to the hospital due to vomiting and diarrhoea. Autopsy findings revealed cyanosis of finger nails and ears. Internal examination revealed; large heart, weighing 60 grams, single ventricle, without a septum and upper membranous part. Single ventricle is a rare pathology, hence, this paper aims to discuss this case from a medico-legal point of view. (author)

  5. Single photon emission tomography

    International Nuclear Information System (INIS)

    Buvat, Irene

    2011-09-01

    The objective of this lecture is to present the single photon emission computed tomography (SPECT) imaging technique. Content: 1 - Introduction: anatomic, functional and molecular imaging; Principle and role of functional or molecular imaging; 2 - Radiotracers: chemical and physical constraints, main emitters, radioisotopes production, emitters type and imaging techniques; 3 - Single photon emission computed tomography: gamma cameras and their components, gamma camera specifications, planar single photon imaging characteristics, gamma camera and tomography; 4 - Quantification in single photon emission tomography: attenuation, scattering, un-stationary spatial resolution, partial volume effect, movements, others; 5 - Synthesis and conclusion

  6. Geological discrete fracture network model for the Laxemar site. Site Descriptive Modelling. SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    La Pointe, Paul; Fox, Aaron (Golder Associates Inc (United States)); Hermanson, Jan; Oehman, Johan (Golder Associates AB, Stockholm (Sweden))

    2008-12-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is performing site characterization at two different locations, Forsmark and Laxemar, in order to locate a site for a final geologic repository for spent nuclear fuel. The program is built upon the development of Site Descriptive Models (SDMs) at specific timed data freezes. Each SDM is formed from discipline-specific reports from across the scientific spectrum. This report describes the methods, analyses, and conclusions of the modelling team in the production of the SDM-Site Laxemar geological discrete-fracture network (DFN) model. The DFN builds upon the work of other geological models, including the deformation zone and rock domain models. The geological DFN is a statistical model for stochastically simulating rock fractures and minor deformation zones at a scale of less than 1,000 m (the lower cut-off of the DZ models). The geological DFN is valid within six distinct fracture domains inside the Laxemar local model subarea: FSM{sub C}, FSM{sub E}W007, FSM{sub N}, FSM{sub N}E005, FSM{sub S}, and FSM{sub W}. The models are built using data from detailed surface outcrop maps, geophysical lineament maps, and the cored borehole record at Laxemar. The conceptual model for the SDM-Site Laxemar geological DFN model revolves around the identification of fracture domains based on relative fracture set intensities, orientation clustering, and the regional tectonic framework (including deformation zones). A single coupled fracture size/fracture intensity concept (the Base Model) based on a Pareto (power-law) distribution for fracture sizes was chosen as the recommended parameterisation. A slew of alternative size-intensity models were also carried through the fracture analyses and into the uncertainty and model verification analyses. Uncertainty is modelled by analysing the effects on fracture intensity (P32) that alternative model cases can have. Uncertainty is parameterised as a ratio between the P32 of the

  7. Geological discrete fracture network model for the Laxemar site. Site Descriptive Modelling. SDM-Site Laxemar

    International Nuclear Information System (INIS)

    La Pointe, Paul; Fox, Aaron; Hermanson, Jan; Oehman, Johan

    2008-10-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is performing site characterization at two different locations, Forsmark and Laxemar, in order to locate a site for a final geologic repository for spent nuclear fuel. The program is built upon the development of Site Descriptive Models (SDMs) at specific timed data freezes. Each SDM is formed from discipline-specific reports from across the scientific spectrum. This report describes the methods, analyses, and conclusions of the modelling team in the production of the SDM-Site Laxemar geological discrete-fracture network (DFN) model. The DFN builds upon the work of other geological models, including the deformation zone and rock domain models. The geological DFN is a statistical model for stochastically simulating rock fractures and minor deformation zones at a scale of less than 1,000 m (the lower cut-off of the DZ models). The geological DFN is valid within six distinct fracture domains inside the Laxemar local model subarea: FSM C , FSM E W007, FSM N , FSM N E005, FSM S , and FSM W . The models are built using data from detailed surface outcrop maps, geophysical lineament maps, and the cored borehole record at Laxemar. The conceptual model for the SDM-Site Laxemar geological DFN model revolves around the identification of fracture domains based on relative fracture set intensities, orientation clustering, and the regional tectonic framework (including deformation zones). A single coupled fracture size/fracture intensity concept (the Base Model) based on a Pareto (power-law) distribution for fracture sizes was chosen as the recommended parameterisation. A slew of alternative size-intensity models were also carried through the fracture analyses and into the uncertainty and model verification analyses. Uncertainty is modelled by analysing the effects on fracture intensity (P32) that alternative model cases can have. Uncertainty is parameterised as a ratio between the P32 of the alternative model and the P

  8. 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.

  9. Sellafield site (including Drigg) emergency scheme manual

    International Nuclear Information System (INIS)

    1987-02-01

    This Emergency Scheme defines the organisation and procedures available should there be an accident at the Sellafield Site which results in, or may result in, the release of radioactive material, or the generation of a high radiation field, which might present a hazard to employees and/or the general public. This manual covers the general principles of the total emergency scheme and those detailed procedures which are not specific to any single department. (U.K.)

  10. Experimental site and design

    Energy Technology Data Exchange (ETDEWEB)

    Guenette, C. C. [SINTEF Applied Cemistry, Trondheim (Norway)

    1999-08-01

    Design and site selection criteria for the Svalbard oil spill experiments are described. All three experimental sites have coarse and mixed sediment beaches of sand and pebble; within each site wave exposure is very similar; along-shore and across-shore sediment characteristics are also relatively homogeneous. Tidal range is in the order of 0.6 m at neaps, and 1.8 m at springs. All three sites are open to wave action and are ice-free during the experimental period of mid-July to mid-October. Study plots at each site were selected for different treatments from within the continuous stretch of oiled shoreline, with oiled buffer zones between plots and at either end of the oiled zone. Treatments included mixing (tilling), sediment relocation (surf washing) and bioremediation (nutrient enrichment). Measurements and observations were carried out during the summers of 1997 and 1998. The characteristics measured were: wave and wind conditions; beach topography and elevation; sediment grain size distribution; mineral fines size distribution and mineral composition; background hydrocarbons; concentration of oil within experimental plots and the rate of oil loss over time; depth of oil penetration and thickness of the oiled sediment layer; oil concentration and toxicity of near-shore benthic sediments; mineral composition of suspended particulate material captured in sub-tidal sediment traps; and oil-fines interaction in near-shore water samples. 1 fig.

  11. Experimental site and design

    Energy Technology Data Exchange (ETDEWEB)

    Guenette, C. C. [SINTEF Applied Cemistry, Trondheim (Norway)

    1999-07-01

    Design and site selection criteria for the Svalbard oil spill experiments are described. All three experimental sites have coarse and mixed sediment beaches of sand and pebble; within each site waveexposure is very similar; along-shore and across-shore sediment characteristics are also relatively homogeneous. Tidal range is in the order of 0.6 m at neaps, and 1.8 m at springs. All three sites are open to wave action and are ice-free during the experimental period of mid-July to mid-October. Study plots at each site were selected for different treatments from within the continuous stretch of oiled shoreline, with oiled buffer zones between plots and at either end of the oiled zone. Treatments included mixing (tilling), sediment relocation (surf washing) and bioremediation (nutrient enrichment). Measurements and observations were carried out during the summers of 1997 and 1998. The characteristics measured were: wave and wind conditions; beach topography and elevation; sediment grain size distribution; mineral fines size distribution and mineral composition; background hydrocarbons; concentration of oil within experimental plots and the rate of oil loss over time; depth of oil penetration and thickness of the oiled sediment layer; oil concentration and toxicity of near-shore benthic sediments; mineral composition of suspended particulate material captured in sub-tidal sediment traps; and oil-fines interaction in near-shore water samples. 1 fig.

  12. Criteria of site assessment

    International Nuclear Information System (INIS)

    Gibbs, P.; Fuchs, H.

    1975-01-01

    The criteria which lead to the choice of a particular site for a nuclear power station are in general very similar to those which would apply to any other type of power station. The principal differences derive from the simpler transport problems for the fuel compared with, say, solid fuel and the special safety considerations which attach to nuclear reactors. The search for a suitable site obviously starts by considering where the power is needed, i.e. where the load centers are and also the existing transmission network which may help to bring the power from a more remote site to the load centers. This economic incentive to put the plant close to loads conflicts directly with the nuclear safety argument which favours more remote siting, and part of the problem of site selection is to reconcile these two matters. In addition, there are many other important matters which will be considered later concerning the adequacy of cooling water supplies, foundation conditions, etc., all of which must be examined in considerable detail. (orig./TK) [de

  13. Repository site characterization

    International Nuclear Information System (INIS)

    Voss, J.W.; Pentz, D.L.

    1987-01-01

    The characterization of candidate repository sites has a number of programmatic objectives. Principal among these is the acquisition of data: a) to determine the suitability of a site relative to the DOE repository siting guidelines, b) to support model development and calculations to determine the suitability of a site relative to the post closure criteria of the NRC and EPA, c) to support the design of a disposal system, including the waste package and the engineered barrier system, as well as the shafts and underground openings of the repository. In meeting the gaols of site characterization, the authors have an obligation to conduct their investigations within an appropriate budget and schedule. This mandates that a well-constructed and systematic plan for field investigations be developed. Such a plan must fully account for the mechanisms which will control the radiologic performance in the repository. The plan must also flexibly and dynamically respond to the results of each step of field investigation, responding to the spatial variability of earth as well as to enhanced understandings of the performance of the disposal system. Such a plan must ensure that sufficient data are available to support the necessary probabilistic calculations of performance. This paper explores the planning for field data acquisition with specific reference to requirements for demonstrations of the acceptable performance for disposal systems

  14. Site 300 SPCC Plan

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-11-23

    This Spill Prevention, Control, and Countermeasure (SPCC) Plan describes the measures that are taken at Lawrence Livermore National Laboratory’s (LLNL) Experimental Test Site (Site 300) near Tracy, California, to prevent, control, and handle potential spills from aboveground containers that can contain 55 gallons or more of oil. This SPCC Plan complies with the Oil Pollution Prevention regulation in Title 40 of the Code of Federal Regulations, Part 112 (40 CFR 112) and with 40 CFR 761.65(b) and (c), which regulates the temporary storage of polychlorinated biphenyls (PCBs). This Plan has also been prepared in accordance with Division 20, Chapter 6.67 of the California Health and Safety Code (HSC 6.67) requirements for oil pollution prevention (referred to as the Aboveground Petroleum Storage Act [APSA]), and the United States Department of Energy (DOE) Order No. 436.1. This SPCC Plan establishes procedures, methods, equipment, and other requirements to prevent the discharge of oil into or upon the navigable waters of the United States or adjoining shorelines for aboveground oil storage and use at Site 300. This SPCC Plan has been prepared for the entire Site 300 facility and replaces the three previous plans prepared for Site 300: LLNL SPCC for Electrical Substations Near Buildings 846 and 865 (LLNL 2015), LLNL SPCC for Building 883 (LLNL 2015), and LLNL SPCC for Building 801 (LLNL 2014).

  15. Sensing single electrons with single molecules

    International Nuclear Information System (INIS)

    Plakhotnik, Taras

    2007-01-01

    We propose a new methodology for probing transport of just one electron, a process of great importance both in nature and in artificial devices. Our idea for locating a single electron is analogues to the conventional GPS where signals from several satellites are used to locate a macro object. Using fluorescent molecules as tiny sensors, it is possible to determine 3D displacement vector of an electron

  16. SFR site investigation. Bedrock Hydrogeochemistry

    International Nuclear Information System (INIS)

    Nilsson, Ann-Chatrin; Tullborg, Eva-Lena; Smellie, John; Gimeno, Maria J.; Gomez, Javier B.; Auque, Luis F.; Sandstroem, Bjoern; Pedersen, Karsten

    2011-11-01

    There are plans that the final repository for low and intermediate level radioactive waste, SFR, located about 150 km north of Stockholm, will be extended. Geoscientific studies to define and characterise a suitable bedrock volume for the extended repository have been carried out from 2007 to 2011, and have included the drilling and evaluation of seven new core drilled and four percussion boreholes. These new data, together with existing data extending back to 1985, have been interpreted and modelled in order to provide the necessary information for safety assessment and repository design. This report presents the final hydrogeochemical site description for the SFR site, and will constitute a background report for the integrated site description (the SFR Site Descriptive Model version 1.0) together with corresponding reports from the geological and hydrogeological disciplines. Most of the hydrogeochemical data from the field investigations consist of major ions and isotopes together with sporadic gas, microbe and measured redox data. Despite the close proximity of the Forsmark site, few data from this source are of relevance because of the shallow nature of the SFR site, the fact that SFR is located beneath the Baltic Sea and also the drawdown/upconing impacts of its construction on the hydrogeochemistry. This artificially imposed dynamic flow system is naturally more prevalent along major deformation fracture zones of higher transmissivity, whilst lower transmissive fractures together with the less transmissive bedrock masses between major deformation zones, still retain some evidence of the natural groundwater mixing patterns established prior to the SFR construction. The groundwaters in the SFR dataset cover a depth down to -250 m.a.s.l. with single sampling locations at -300 and -400 m.a.s.l. and represent a relatively limited salinity range (1,500 to 5,500 mg/L chloride). However, the δ 18 O values show a wide variation (-15.5 to -7.5 per mille V

  17. SFR site investigation. Bedrock Hydrogeochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Ann-Chatrin [Geosigma AB, Uppsala (Sweden); Tullborg, Eva-Lena [Terralogica AB, Graabo (Sweden); Smellie, John [Conterra AB, Uppsala (Sweden); Gimeno, Maria J.; Gomez, Javier B.; Auque, Luis F. [Univ. of Zaragoza, Zaragoza (Spain); Sandstroem, Bjoern [WSP Sverige AB, Goeteborg (Sweden); Pedersen, Karsten [Micans AB, Moelnlycke (Sweden)

    2011-11-15

    There are plans that the final repository for low and intermediate level radioactive waste, SFR, located about 150 km north of Stockholm, will be extended. Geoscientific studies to define and characterise a suitable bedrock volume for the extended repository have been carried out from 2007 to 2011, and have included the drilling and evaluation of seven new core drilled and four percussion boreholes. These new data, together with existing data extending back to 1985, have been interpreted and modelled in order to provide the necessary information for safety assessment and repository design. This report presents the final hydrogeochemical site description for the SFR site, and will constitute a background report for the integrated site description (the SFR Site Descriptive Model version 1.0) together with corresponding reports from the geological and hydrogeological disciplines. Most of the hydrogeochemical data from the field investigations consist of major ions and isotopes together with sporadic gas, microbe and measured redox data. Despite the close proximity of the Forsmark site, few data from this source are of relevance because of the shallow nature of the SFR site, the fact that SFR is located beneath the Baltic Sea and also the drawdown/upconing impacts of its construction on the hydrogeochemistry. This artificially imposed dynamic flow system is naturally more prevalent along major deformation fracture zones of higher transmissivity, whilst lower transmissive fractures together with the less transmissive bedrock masses between major deformation zones, still retain some evidence of the natural groundwater mixing patterns established prior to the SFR construction. The groundwaters in the SFR dataset cover a depth down to -250 m.a.s.l. with single sampling locations at -300 and -400 m.a.s.l. and represent a relatively limited salinity range (1,500 to 5,500 mg/L chloride). However, the {delta}{sup 18}O values show a wide variation (-15.5 to -7.5 per mille V

  18. Superfund and Toxic Release Inventory Sites - MDC_ContaminatedSite

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — A point feature class of open DERM Contaminated sites - see phase code for status of site. Contaminated sites identifies properties where environmental contamination...

  19. Single-sided NMR

    CERN Document Server

    Casanova, Federico; Blümich, Bernhard

    2011-01-01

    Single-Sided NMR describes the design of the first functioning single-sided tomograph, the related measurement methods, and a number of applications. One of the key advantages to this method is the speed at which the images are obtained.

  20. Understanding Single Adulthood.

    Science.gov (United States)

    Stein, Peter J.

    The life styles and life chances of the unmarried include elements of choices. Singles may be grouped and characterized according to whether their status may be considered stable or temporary. A life cycle, or continuum model of singlehood is reviewed, including its different factors, or phases. A new model for singles is proposed--a life spiral…

  1. Single gaze gestures

    DEFF Research Database (Denmark)

    Møllenbach, Emilie; Lilholm, Martin; Gail, Alastair

    2010-01-01

    This paper examines gaze gestures and their applicability as a generic selection method for gaze-only controlled interfaces. The method explored here is the Single Gaze Gesture (SGG), i.e. gestures consisting of a single point-to-point eye movement. Horizontal and vertical, long and short SGGs were...

  2. Siting and public acceptance

    International Nuclear Information System (INIS)

    De Lise, Pasquale.

    1977-01-01

    The paper discusses the problem of nuclear power plant siting according to presently applicable legislation in Italy, taking into account urban and environmental aspects. Act No 393 of 2 August 1975 on the siting of nuclear plants introduced a significant change in that prior to its adoption, the competence to license nuclear installations was divided amongst so many bodies that approval was inevitably delayed. Act No. 393 lays down the siting procedure which involves authorities at regional and State level and provides a step by step consultation of the Communes concerned and gives them a time limit for replying to the proposed project, while enabling the necessary scientific, environmental and urban investigations to be made. Thus although ultimate decisions rest with the State, the regional bodies representing the public have a voice in them. In such planning the authorities must take into account the public interest, from the environmental and social angles as well as political and economic interests. (NEA) [fr

  3. Measuring site occupancy

    DEFF Research Database (Denmark)

    Rogowska-Wrzesinska, Adelina; Wojdyla, Katarzyna; Williamson, James

    2014-01-01

    occupancy of the modification site. We show that, on one hand, heavily modified cysteines are not necessarily involved in the response to oxidative stress. On the other hand residues with low modification level can be dramatically affected by mild oxidative imbalance. We make use of high resolution mass...... peptides corresponding to 90 proteins. Only 6 modified peptides changed significantly under mild oxidative stress. Quantitative information allowed us to determine relative modification site occupancy of each identified modified residue and pin point heavily modified ones. The method proved to be precise...... and sensitive enough to detect and quantify endogenous levels of oxidative stress on proteome-wide scale and brings a new perspective on the role of the modification site occupancy in cellular redox response....

  4. Single molecules and nanotechnology

    CERN Document Server

    Vogel, Horst

    2007-01-01

    This book focuses on recent advances in the rapidly evolving field of single molecule research. These advances are of importance for the investigation of biopolymers and cellular biochemical reactions, and are essential to the development of quantitative biology. Written by leading experts in the field, the articles cover a broad range of topics, including: quantum photonics of organic dyes and inorganic nanoparticles their use in detecting properties of single molecules the monitoring of single molecule (enzymatic) reactions single protein (un)folding in nanometer-sized confined volumes the dynamics of molecular interactions in biological cells The book is written for advanced students and scientists who wish to survey the concepts, techniques and results of single molecule research and assess them for their own scientific activities.

  5. Single-photon imaging

    CERN Document Server

    Seitz, Peter

    2011-01-01

    The acquisition and interpretation of images is a central capability in almost all scientific and technological domains. In particular, the acquisition of electromagnetic radiation, in the form of visible light, UV, infrared, X-ray, etc. is of enormous practical importance. The ultimate sensitivity in electronic imaging is the detection of individual photons. With this book, the first comprehensive review of all aspects of single-photon electronic imaging has been created. Topics include theoretical basics, semiconductor fabrication, single-photon detection principles, imager design and applications of different spectral domains. Today, the solid-state fabrication capabilities for several types of image sensors has advanced to a point, where uncoooled single-photon electronic imaging will soon become a consumer product. This book is giving a specialist´s view from different domains to the forthcoming “single-photon imaging” revolution. The various aspects of single-photon imaging are treated by internati...

  6. Single Nanoparticle Plasmonic Sensors

    Directory of Open Access Journals (Sweden)

    Manish Sriram

    2015-10-01

    Full Text Available The adoption of plasmonic nanomaterials in optical sensors, coupled with the advances in detection techniques, has opened the way for biosensing with single plasmonic particles. Single nanoparticle sensors offer the potential to analyse biochemical interactions at a single-molecule level, thereby allowing us to capture even more information than ensemble measurements. We introduce the concepts behind single nanoparticle sensing and how the localised surface plasmon resonances of these nanoparticles are dependent upon their materials, shape and size. Then we outline the different synthetic approaches, like citrate reduction, seed-mediated and seedless growth, that enable the synthesis of gold and silver nanospheres, nanorods, nanostars, nanoprisms and other nanostructures with tunable sizes. Further, we go into the aspects related to purification and functionalisation of nanoparticles, prior to the fabrication of sensing surfaces. Finally, the recent developments in single nanoparticle detection, spectroscopy and sensing applications are discussed.

  7. 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....

  8. 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.

  9. Hydroelectric generating site signage

    Energy Technology Data Exchange (ETDEWEB)

    Bentley, K [British Columbia Hydro, Vancouver, BC (Canada)

    1997-04-01

    Recreational sites have been developed at several BC Hydro reservoirs. These sites are visited by approximately 800,000 people annually and therefore, require consistent control measures to ensure public safety and to restrict public access to hazardous areas. BC Hydro is in the process of establishing a province-wide standard in which layout, colour, description of hazards, BC Hydro identity and sign placement would follow an established set of criteria. Proposed signs would consist of a pictograph and a printed warning below. Preliminary designs for 16 of the signs were presented. 16 figs.

  10. PhosphoSiteAnalyzer

    DEFF Research Database (Denmark)

    Bennetzen, Martin V; Cox, Jürgen; Mann, Matthias

    2012-01-01

    an algorithm to retrieve kinase predictions from the public NetworKIN webpage in a semiautomated way and applies hereafter advanced statistics to facilitate a user-tailored in-depth analysis of the phosphoproteomic data sets. The interface of the software provides a high degree of analytical flexibility......Phosphoproteomic experiments are routinely conducted in laboratories worldwide, and because of the fast development of mass spectrometric techniques and efficient phosphopeptide enrichment methods, researchers frequently end up having lists with tens of thousands of phosphorylation sites...... and is designed to be intuitive for most users. PhosphoSiteAnalyzer is a freeware program available at http://phosphosite.sourceforge.net ....

  11. Multi-Sited Resilience

    DEFF Research Database (Denmark)

    Olwig, Mette Fog

    2012-01-01

    with natural disasters and climate change. In a globalized world, however, it is hard to discern what is “local” as global organizations play an increasingly visible and powerful role. This paper will argue that local understandings and practices of resilience cannot be disentangled from global understandings...... flooding in northern Ghana, this paper examines the mutual construction of “local” and “global” notions and practices of resilience through multi-sited processes. It is based on interviews and participant observation in multiple sites at the “local,” “regional” and “global” levels....

  12. 3D local structure around copper site of rabbit prion-related protein: Quantitative determination by XANES spectroscopy combined with multiple-scattering calculations

    International Nuclear Information System (INIS)

    Cui, P.X.; Lian, F.L.; Wang, Y.; Wen, Yi; Chu, W.S.; Zhao, H.F.; Zhang, S.; Li, J.; Lin, D.H.; Wu, Z.Y.

    2014-01-01

    Prion-related protein (PrP), a cell-surface copper-binding glycoprotein, is considered to be responsible for a number of transmissible spongiform encephalopathies (TSEs). The structural conversion of PrP from the normal cellular isoform (PrP C ) to the post-translationally modified form (PrP Sc ) is thought to be relevant to Cu 2+ binding to histidine residues. Rabbits are one of the few mammalian species that appear to be resistant to TSEs, because of the structural characteristics of the rabbit prion protein (RaPrP C ) itself. Here we determined the three-dimensional local structure around the C-terminal high-affinity copper-binding sites using X-ray absorption near-edge structure combined with ab initio calculations in the framework of the multiple-scattering (MS) theory. Result shows that two amino acid resides, Gln97 and Met108, and two histidine residues, His95 and His110, are involved in binding this copper(II) ion. It might help us understand the roles of copper in prion conformation conversions, and the molecular mechanisms of prion-involved diseases. - Highlights: ► The first structure of the metal ion binding site in RaPrP fifth copper-binding site. ► Quantitative determination by XANES spectroscopy combined with ab initio calculations. ► Provide a proof of the roles of copper in prion conformation conversions. ► Provide a proof of the molecular mechanisms of prion-involved diseases

  13. Flexible single-incision surgery: a fusion technique.

    Science.gov (United States)

    Noguera, José F; Dolz, Carlos; Cuadrado, Angel; Olea, José; García, Juan

    2013-06-01

    The development of natural orifice transluminal endoscopic surgery has led to other techniques, such as single-incision surgery. The use of the flexible endoscope for single-incision surgery paves the way for further refinement of both surgical methods. To describe a new, single-incision surgical technique, namely, flexible single-incision surgery. Assessment of the safety and effectiveness of endoscopic cholecystectomy in a series of 30 patients. This technique consists of a single umbilical incision through which a flexible endoscope is introduced and consists of 2 parallel entry ports that provide access to nonarticulated laparoscopic instruments. The technique was applied in all patients for whom it was prescribed. No general or surgical wound complications were noted. Surgical time was no longer than usual for single-port surgery. Flexible single-incision surgery is a new single-site surgical technique offering the same level of patient safety, with additional advantages for the surgeon at minimal cost.

  14. Allegheny County Illegal Dump Sites

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The Illegal Dump Site dataset includes information on illegal dump sites, their type of trash, and the estimate tons of trash at each site. The information was...

  15. Sites and Enactments

    DEFF Research Database (Denmark)

    Korsgaard, Steffen T.; Neergaard, Helle

    2008-01-01

    is formulated where opportunities are seen as dynamic in the sense that they are enacted in different social practices at different sites. The method is illustrated through an analysis of the birth of The Republic of Tea, a very successful tea company, as presented in the book "The Republic of Tea"....

  16. Hanford site environment

    International Nuclear Information System (INIS)

    Isaacson, R.E.

    1976-01-01

    A synopsis is given of the detailed characterization of the existing environment at Hanford. The following aspects are covered: demography, land use, meteorology, geology, hydrology, and seismology. It is concluded that Hanford is one of the most extensively characterized nuclear sites

  17. Mathematics. [SITE 2002 Section].

    Science.gov (United States)

    Connell, Michael L., Ed.; Lowery, Norene Vail, Ed.; Harnisch, Delwyn L., Ed.

    This document contains the following papers on mathematics from the SITE (Society for Information Technology & Teacher Education) 2002 conference: (1) "Teachers' Learning of Mathematics in the Presence of Technology: Participatory Cognitive Apprenticeship" (Mara Alagic); (2) "A Fractal Is a Pattern in Your Neighborhood" (Craig N. Bach); (3)…

  18. 2014 Site Environmental Report

    Energy Technology Data Exchange (ETDEWEB)

    Paquette, Douglas [Brookhaven National Lab. (BNL), Upton, NY (United States); Remien, Jason [Brookhaven National Lab. (BNL), Upton, NY (United States); Foley, Brian [Brookhaven National Lab. (BNL), Upton, NY (United States); Burke, John [Brookhaven National Lab. (BNL), Upton, NY (United States); Dorsch, William [Brookhaven National Lab. (BNL), Upton, NY (United States); Ratel, Karen [Brookhaven National Lab. (BNL), Upton, NY (United States); Howe, Robert [Brookhaven National Lab. (BNL), Upton, NY (United States); Welty, Tim [Brookhaven National Lab. (BNL), Upton, NY (United States); Williams, Jeffrey [Brookhaven National Lab. (BNL), Upton, NY (United States); Pohlpt, Peter [Brookhaven National Lab. (BNL), Upton, NY (United States); Lagattolla, Richard [Brookhaven National Lab. (BNL), Upton, NY (United States); Metz, Robert [Brookhaven National Lab. (BNL), Upton, NY (United States); Milligan, James [Brookhaven National Lab. (BNL), Upton, NY (United States); Lettieri, Lawrence [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-10-01

    BNL prepares an annual Site Environmental Report (SER) in accordance with DOE Order 231.1B, Environment, Safety and Health Reporting. The report is written to inform the public, regulators, employees, and other stakeholders of the Laboratory’s environmental performance during the calendar year in review.

  19. Single-Arc IMRT?

    International Nuclear Information System (INIS)

    Bortfeld, Thomas; Webb, Steve

    2009-01-01

    The idea of delivering intensity-modulated radiation therapy (IMRT) with a multileaf collimator in a continuous dynamic mode during a single rotation of the gantry has recently gained momentum both in research and industry. In this note we investigate the potential of this Single-Arc IMRT technique at a conceptual level. We consider the original theoretical example case from Brahme et al that got the field of IMRT started. Using analytical methods, we derive deliverable intensity 'landscapes' for Single-Arc as well as standard IMRT and Tomotherapy. We find that Tomotherapy provides the greatest flexibility in shaping intensity landscapes and that it allows one to deliver IMRT in a way that comes close to the ideal case in the transverse plane. Single-Arc and standard IMRT make compromises in different areas. Only in relatively simple cases that do not require substantial intensity modulation will Single-Arc be dosimetrically comparable to Tomotherapy. Compared with standard IMRT, Single-Arc could be dosimetrically superior in certain cases if one is willing to accept the spreading of low dose values over large volumes of normal tissue. In terms of treatment planning, Single-Arc poses a more challenging optimization problem than Tomotherapy or standard IMRT. We conclude that Single-Arc holds potential as an efficient IMRT technique especially for relatively simple cases. In very complex cases, Single-Arc may unduly compromise the quality of the dose distribution, if one tries to keep the treatment time below 2 min or so. As with all IMRT techniques, it is important to explore the tradeoff between plan quality and the efficiency of its delivery carefully for each individual case. (note)

  20. Small Wind Site Assessment Guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, Tim [Advanced Energy Systems LLC, Eugene, OR (United States); Preus, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-09-01

    Site assessment for small wind energy systems is one of the key factors in the successful installation, operation, and performance of a small wind turbine. A proper site assessment is a difficult process that includes wind resource assessment and the evaluation of site characteristics. These guidelines address many of the relevant parts of a site assessment with an emphasis on wind resource assessment, using methods other than on-site data collection and creating a small wind site assessment report.

  1. Single neuron computation

    CERN Document Server

    McKenna, Thomas M; Zornetzer, Steven F

    1992-01-01

    This book contains twenty-two original contributions that provide a comprehensive overview of computational approaches to understanding a single neuron structure. The focus on cellular-level processes is twofold. From a computational neuroscience perspective, a thorough understanding of the information processing performed by single neurons leads to an understanding of circuit- and systems-level activity. From the standpoint of artificial neural networks (ANNs), a single real neuron is as complex an operational unit as an entire ANN, and formalizing the complex computations performed by real n

  2. Single photon ECT

    International Nuclear Information System (INIS)

    Maeda, Toshio; Matsuda, Hiroshi; Tada, Akira; Bunko, Hisashi; Koizumi, Kiyoshi

    1982-01-01

    The detectability of lesions located deep in a body or overlapped with a physiologically increased activity improve with the help of single photon ECT. In some cases, the ECT is superior to the conventional gamma camera images and X-ray CT scans in the evaluation of the location and size of lesion. The single photon ECT of the brain compares favorably with the contrast enhansed X-ray CT scans. The most important adaptation of the single photon ECT are the detection of recurrent brain tumors after craniotomy and the evaluation of ischemic heart diseases. (author)

  3. Single Electron Tunneling

    International Nuclear Information System (INIS)

    Ruggiero, Steven T.

    2005-01-01

    Financial support for this project has led to advances in the science of single-electron phenomena. Our group reported the first observation of the so-called ''Coulomb Staircase'', which was produced by tunneling into ultra-small metal particles. This work showed well-defined tunneling voltage steps of width e/C and height e/RC, demonstrating tunneling quantized on the single-electron level. This work was published in a now well-cited Physical Review Letter. Single-electron physics is now a major sub-field of condensed-matter physics, and fundamental work in the area continues to be conducted by tunneling in ultra-small metal particles. In addition, there are now single-electron transistors that add a controlling gate to modulate the charge on ultra-small photolithographically defined capacitive elements. Single-electron transistors are now at the heart of at least one experimental quantum-computer element, and single-electron transistor pumps may soon be used to define fundamental quantities such as the farad (capacitance) and the ampere (current). Novel computer technology based on single-electron quantum dots is also being developed. In related work, our group played the leading role in the explanation of experimental results observed during the initial phases of tunneling experiments with the high-temperature superconductors. When so-called ''multiple-gap'' tunneling was reported, the phenomenon was correctly identified by our group as single-electron tunneling in small grains in the material. The main focus throughout this project has been to explore single electron phenomena both in traditional tunneling formats of the type metal/insulator/particles/insulator/metal and using scanning tunneling microscopy to probe few-particle systems. This has been done under varying conditions of temperature, applied magnetic field, and with different materials systems. These have included metals, semi-metals, and superconductors. Amongst a number of results, we have

  4. 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.

  5. A Single Atom Antenna

    International Nuclear Information System (INIS)

    Trinter, Florian; Williams, Joshua B; Weller, Miriam; Waitz, Markus; Pitzer, Martin; Voigtsberger, Jörg; Schober, Carl; Kastirke, Gregor; Müller, Christian; Goihl, Christoph; Burzynski, Phillip; Wiegandt, Florian; Wallauer, Robert; Kalinin, Anton; Schmidt, Lothar Ph H; Schöffler, Markus S; Jahnke, Till; Dörner, Reinhard; Chiang, Ying-Chih; Gokhberg, Kirill

    2015-01-01

    Here we demonstrate the smallest possible implementation of an antenna-receiver complex which consists of a single (helium) atom acting as the antenna and a second (neon) atom acting as a receiver. (paper)

  6. Single Beam Holography.

    Science.gov (United States)

    Chen, Hsuan; Ruterbusch, Paul H.

    1979-01-01

    Discusses how holography can be used as part of undergraduate physics laboratories. The authors propose a single beam technique of holography, which will reduce the recording scheme as well as relax the isolation requirements. (HM)

  7. Single-photon sources

    International Nuclear Information System (INIS)

    Lounis, Brahim; Orrit, Michel

    2005-01-01

    The concept of the photon, central to Einstein's explanation of the photoelectric effect, is exactly 100 years old. Yet, while photons have been detected individually for more than 50 years, devices producing individual photons on demand have only appeared in the last few years. New concepts for single-photon sources, or 'photon guns', have originated from recent progress in the optical detection, characterization and manipulation of single quantum objects. Single emitters usually deliver photons one at a time. This so-called antibunching of emitted photons can arise from various mechanisms, but ensures that the probability of obtaining two or more photons at the same time remains negligible. We briefly recall basic concepts in quantum optics and discuss potential applications of single-photon states to optical processing of quantum information: cryptography, computing and communication. A photon gun's properties are significantly improved by coupling it to a resonant cavity mode, either in the Purcell or strong-coupling regimes. We briefly recall early production of single photons with atomic beams, and the operation principles of macroscopic parametric sources, which are used in an overwhelming majority of quantum-optical experiments. We then review the photophysical and spectroscopic properties and compare the advantages and weaknesses of various single nanometre-scale objects used as single-photon sources: atoms or ions in the gas phase and, in condensed matter, organic molecules, defect centres, semiconductor nanocrystals and heterostructures. As new generations of sources are developed, coupling to cavities and nano-fabrication techniques lead to improved characteristics, delivery rates and spectral ranges. Judging from the brisk pace of recent progress, we expect single photons to soon proceed from demonstrations to applications and to bring with them the first practical uses of quantum information

  8. Single particle dynamics

    International Nuclear Information System (INIS)

    Siemens, P.J.; Jensen, A.S.

    1985-01-01

    It is shown that the opening of the 3-quasiparticle continuum at 3Δ sets the energy scale for the enhancement of the effective mass near the Fermi surface of nuclei. The authors argue that the spreading width of single-particle states due to coupling with low-lying collective modes is qualitatively different from the two-body collision mechanism, and contributes little to the single-particle lifetime in the sense of the optical model. (orig.)

  9. Olkiluoto site description 2006

    International Nuclear Information System (INIS)

    Andersson, J.; Ahokas, H.; Hudson, J.A.

    2007-03-01

    This second version of the Olkiluoto Site Report, produced by the OMTF (Olkiluoto Modelling Task Force), updates the Olkiluoto Site Report 2004 (Posiva 2005) with the data and knowledge obtained up to December 2005. The main product of the modelling has been to develop a descriptive model of the site (the Site Descriptive Model), i.e. a model describing the geometry, properties of the bedrock and the water and the associated interacting processes and mechanisms. For practical reasons, the Site Descriptive Model is divided into five parts: surface system, geology, rock mechanics, hydrogeology and hydrogeochemistry, which are presented in individual chapters. Four separated models are presented: the geological, rock mechanics, hydrogeological and hydrogeochemical models. The consistency between the hydrogeological and hydrogeochemical models is assessed in a joint chapter. Chapter 1 presents an outline of the report, explains the background to its development and sets out its objectives and scope. It is also introduces and explains the integrated modelling methodology, the nomenclature used in the descriptions of the models and the prediction/outcome studies. Chapter 2 provides a brief overview of the data used for producing the Site Description. Chapters 3 to 8 present the descriptive modelling, which involves interpreting data, interpolating or extrapolating between measurement points and calibrating the model against data, based on the various assumptions made about each conceptual model. Chapter 9 presents the results of the prediction/outcome studies performed during 2005 and Chapter 10 the overall consistency and confidence assessment. Overall conclusions are provided in Chapter 11. The main advances since Site Report 2004 are: A new geological model is presented in Chapter 4, representing a significant change from Bedrock Model 2003/1. There has been extensive use of geological data, whereas hydrogeological data have deliberately not been used and more

  10. 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

  11. Finding protein sites using machine learning methods

    Directory of Open Access Journals (Sweden)

    Jaime Leonardo Bobadilla Molina

    2003-07-01

    Full Text Available The increasing amount of protein three-dimensional (3D structures determined by x-ray and NMR technologies as well as structures predicted by computational methods results in the need for automated methods to provide inital annotations. We have developed a new method for recognizing sites in three-dimensional protein structures. Our method is based on a previosly reported algorithm for creating descriptions of protein microenviroments using physical and chemical properties at multiple levels of detail. The recognition method takes three inputs: 1. A set of control nonsites that share some structural or functional role. 2. A set of control nonsites that lack this role. 3. A single query site. A support vector machine classifier is built using feature vectors where each component represents a property in a given volume. Validation against an independent test set shows that this recognition approach has high sensitivity and specificity. We also describe the results of scanning four calcium binding proteins (with the calcium removed using a three dimensional grid of probe points at 1.25 angstrom spacing. The system finds the sites in the proteins giving points at or near the blinding sites. Our results show that property based descriptions along with support vector machines can be used for recognizing protein sites in unannotated structures.

  12. Geotechnical site assessment methodology

    International Nuclear Information System (INIS)

    Tunbridge, L.W.; Richards, L.R.

    1985-09-01

    A final report summarizing the research conducted on geotechnical site assessment methodology at the Carwynnen test mine in Cornwall. The geological setting of the test site in the Cornubian granite batholith is described. The effect of structure imposed by discontinuities on the engineering behaviour of rock masses is discussed and the scanline survey method of obtaining data on discontinuities in the rock mass is described. The applicability of some methods of statistical analysis for discontinuity data is reviewed. The requirement for remote geophysical methods of characterizing the mass is discussed and experiments using seismic and ultrasonic velocity measurements are reported. Methods of determining the in-situ stresses are described and the final results of a programme of in-situ stress measurements using the overcoring and hydrofracture methods are reported. (author)

  13. Shaft siting decision

    International Nuclear Information System (INIS)

    1987-08-01

    This study identifies and establishes relative guidelines to be used for siting of repository shafts. Weights were determined for the significant factors that impact the selection of shaft locations for a nuclear waste repository in salt. The study identified a total of 45 factors. A panel of experienced mining people utilized the Kepner-Tregoe (K-T) Decision Analysis Process to perform a structured evaluation of each significant shaft siting factor. The evaluation determined that 22 of the factors were absolute constraints and that the other 23 factors were desirable characteristics. The group established the relative weights for each of the 23 desirable characteristics by using a paired comparison method. 8 refs., 2 figs., 5 tabs

  14. IOs as Social Sites

    DEFF Research Database (Denmark)

    Park, Susan M.; Vetterlein, Antje

    Norms research has made significant inroads into examining their emergence and influence in international relations, while recognizing international organizations (IOs) as key social sites for norms to be created and/or disseminated. This paper interrogates how IOs as “organizational platforms......” (Finnemore 1996) influence the norm building process. Going beyond state-centric approaches to norm construction, it argues that the process of taking up a norm by an IO does affect the norm’s power. A norm’s strength is determined by the extent to which it is uncontested and taken for granted as appropriate...... the norm building process in this way provides insight into the effect of IOs as social sites in strengthening a norm....

  15. 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

  16. Web Site Optimisation

    OpenAIRE

    Petrželka, Jiří

    2007-01-01

    This BSc Project was performed during a study stay at the Coventry University, UK. The goal of this project is to enhance the accessibility and usability of an existing company presentation located at http://www.hcc.cz, boost the site's traffic and so increase the company's revenues. The project follows these steps to accomplish this: a ) A partial refactoring of the back-end (PHP scripts). b ) Transformation of the website contents according to the recommendations of the World Wide Web conso...

  17. 1999 SITE ENVIRONMENTAL REPORT

    Energy Technology Data Exchange (ETDEWEB)

    ENGEL-COX,J.; ZIMMERMAN,E.; LEE,R.; WILLIAMS,J.; GREEN,T.; PAQUETTE,D.; HOODA,B.; SCARPITTA,S.; GENZER,P.; ET AL

    2000-09-01

    Throughout the scientific community, Brookhaven National Laboratory (BNL) is renowned for its leading-edge research in physics, medicine, chemistry, biology, materials, and the environment. BNL is committed to supporting its world-class scientific research with an internationally recognized environmental protection program. The 1999 Site Environmental Report (SER) summarizes the status of the Laboratory's environmental programs and performance, including the steady progress towards cleaning up the site and fully integrating environmental stewardship into all facets of the Laboratory's mission. BNL is located on 5,265 acres of pine barrens in Suffolk County in the center of Long Island, New York. The Laboratory is situated above a sole source aquifer at the headwaters of the Peconic River; therefore, protecting ground and surface water quality is a special concern. Approximately 3,600 acres of the site are undeveloped and serve as habitat for a wide variety of animals and plants, including one New York State endangered species, the tiger salamander, and two New York State threatened species, the banded sunfish and the stiff goldenrod. Monitoring, preserving, and restoring these ecological resources is a high priority for the Laboratory.

  18. Site specific plan

    International Nuclear Information System (INIS)

    Hutchison, J.; Jernigan, G.

    1989-12-01

    The Environmental Restoration and Waste Management Five-Year Plan (FYP) covers the period for FY 1989 through FY 1995. The plan establishes a Department of Energy -- Headquarters (DOE-HQ) agenda for cleanup and compliance against which overall progress can be measured. The FYP covers three areas: Corrective Activities, Environmental Restoration, and Waste Management Operations. Corrective Activities are those activities necessary to bring active or standby facilities into compliance with local, state, and federal environmental regulations. Environmental restoration activities include the assessment and cleanup of surplus facilities and inactive waste sites. Waste management operations includes the treatment, storage, and disposal of wastes which are generated as a result of ongoing operations. This Site Specific Plan (SSP) has been prepared by the Savannah River Site (SRS) in order to show how environmental restoration and waste management activities that were identified during the preparation of the FYP will be implemented, tracked, and reported. The SSP describes DOE Savannah River (DOE-SR) and operating contractor, Westinghouse Savannah River Company (WSRC), organizations that are responsible, for undertaking the activities identified in this plan. The SSP has been prepared in accordance with guidance received from DOE-HQ. DOE-SR is accountable to DOE-HQ for the implementation of this plan. 8 refs., 46 figs., 23 tabs

  19. NOAA History - About This Site

    Science.gov (United States)

    NOAA History Banner gold bar divider home - takes you to index page about the site contacts noaa - takes you to the noaa home page search this site white divider about this site The NOAA History site is the result of the work of many individuals throughout 3d history page NOAA who have been inspired by

  20. Implementing Site-based Budgeting.

    Science.gov (United States)

    Sielke, Catherine C.

    2001-01-01

    Discusses five questions that must be answered before implementing site-based budgeting: Why are we doing this? What budgeting decisions will be devolved to the school site? How do dollars flow from the central office to the site? Who will be involved at the site? How will accountability be achieved? (Author/PKP)