Mechanism of opening a sliding clamp
Douma, Lauren G.; Yu, Kevin K.; England, Jennifer K.
2017-01-01
Abstract Clamp loaders load ring-shaped sliding clamps onto DNA where the clamps serve as processivity factors for DNA polymerases. In the first stage of clamp loading, clamp loaders bind and stabilize clamps in an open conformation, and in the second stage, clamp loaders place the open clamps around DNA so that the clamps encircle DNA. Here, the mechanism of the initial clamp opening stage is investigated. Mutations were introduced into the Escherichia coli β-sliding clamp that destabilize the dimer interface to determine whether the formation of an open clamp loader–clamp complex is dependent on spontaneous clamp opening events. In other work, we showed that mutation of a positively charged Arg residue at the β-dimer interface and high NaCl concentrations destabilize the clamp, but neither facilitates the formation of an open clamp loader–clamp complex in experiments presented here. Clamp opening reactions could be fit to a minimal three-step ‘bind-open-lock’ model in which the clamp loader binds a closed clamp, the clamp opens, and subsequent conformational rearrangements ‘lock’ the clamp loader–clamp complex in a stable open conformation. Our results support a model in which the E. coli clamp loader actively opens the β-sliding clamp. PMID:28973453
Electrostatic Interactions at the Dimer Interface Stabilize the E. coli β Sliding Clamp.
Purohit, Anirban; England, Jennifer K; Douma, Lauren G; Tondnevis, Farzaneh; Bloom, Linda B; Levitus, Marcia
2017-08-22
Sliding clamps are ring-shaped oligomeric proteins that encircle DNA and associate with DNA polymerases for processive DNA replication. The dimeric Escherichia coli β-clamp is closed in solution but must adopt an open conformation to be assembled onto DNA by a clamp loader. To determine what factors contribute to the stability of the dimer interfaces in the closed conformation and how clamp dynamics contribute to formation of the open conformation, we identified conditions that destabilized the dimer and measured the effects of these conditions on clamp dynamics. We characterized the role of electrostatic interactions in stabilizing the β-clamp interface. Increasing salt concentration results in decreased dimer stability and faster subunit dissociation kinetics. The equilibrium dissociation constant of the dimeric clamp varies with salt concentration as predicted by simple charge-screening models, indicating that charged amino acids contribute to the remarkable stability of the interface at physiological salt concentrations. Mutation of a charged residue at the interface (Arg-103) weakens the interface significantly, whereas effects are negligible when a hydrophilic (Ser-109) or a hydrophobic (Ile-305) amino acid is mutated instead. It has been suggested that clamp opening by the clamp loader takes advantage of spontaneous opening-closing fluctuations at the clamp's interface, but our time-resolved fluorescence and fluorescence correlation experiments rule out conformational fluctuations that lead to a significant fraction of open states. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.
Structural analysis of a eukaryotic sliding DNA clamp-clamp loadercomplex.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bowman, Gregory D.; O'Donnell, Mike; Kuriyan, John
2006-06-17
Sliding clamps are ring-shaped proteins that encircle DNA and confer high processivity on DNA polymerases. Here we report the crystal structure of the five-protein clamp loader complex (replication factor-C, RFC) of the yeast Saccharomyces cerevisiae, bound to the sliding clamp (proliferating cell nuclear antigen, PCNA). Tight interfacial coordination of the ATP analogue ATP-?-S by RFC results in a spiral arrangement of the ATPase domains of the clamp loader above the PCNA ring. Placement of a model for primed DNA within the central hole of PCNA reveals a striking correspondence between the RFC spiral and the grooves of the DNA doublemore » helix. This model, in which the clamp loader complex locks onto primed DNA in a screw-cap-like arrangement, provides a simple explanation for the process by which the engagement of primer-template junctions by the RFC:PCNA complex results in ATP hydrolysis and release of the sliding clamp on DNA.« less
Zhuang, Zhihao; Yoder, Bonita L; Burgers, Peter M J; Benkovic, Stephen J
2006-02-21
Numerous proteins that function in DNA metabolic pathways are known to interact with the proliferating cell nuclear antigen (PCNA). The important function of PCNA in stimulating various cellular activities requires its topological linkage with DNA. Loading of the circular PCNA onto duplex DNA requires the activity of a clamp-loader [replication factor C (RFC)] complex and the energy derived from ATP hydrolysis. The mechanistic and structural details regarding PCNA loading by the RFC complex are still developing. In particular, the positive identification of a long-hypothesized structure of an open clamp-RFC complex as an intermediate in loading has remained elusive. In this study, we capture an open yeast PCNA clamp in a complex with RFC through fluorescence energy transfer experiments. We also follow the topological transitions of PCNA in the various steps of the clamp-loading pathway through both steady-state and stopped-flow fluorescence studies. We find that ATP effectively drives the clamp-loading process to completion with the formation of the closed PCNA bound to DNA, whereas ATPgammaS cannot. The information derived from this work complements that obtained from previous structural and mechanistic studies and provides a more complete picture of a eukaryotic clamp-loading pathway using yeast as a paradigm.
Afonso, José P.; Chintakayala, Kiran; Suwannachart, Chatrudee; Sedelnikova, Svetlana; Giles, Kevin; Hoyes, John B.; Soultanas, Panos; Rafferty, John B.; Oldham, Neil J.
2013-01-01
The clamp-loader complex plays a crucial role in DNA replication by loading the β-clamp onto primed DNA to be used by the replicative polymerase. Relatively little is known about the stoichiometry, structure and assembly pathway of this complex, and how it interacts with the replicative helicase, in Gram-positive organisms. Analysis of full and partial complexes by mass spectrometry revealed that a hetero-pentameric τ3-δ-δ′ Bacillus subtilis clamp-loader assembles via multiple pathways, which differ from those exhibited by the Gram-negative model Escherichia coli. Based on this information, a homology model of the B. subtilis τ3-δ-δ′ complex was constructed, which revealed the spatial positioning of the full C-terminal τ domain. The structure of the δ subunit was determined by X-ray crystallography and shown to differ from that of E. coli in the nature of the amino acids comprising the τ and δ′ binding regions. Most notably, the τ-δ interaction appears to be hydrophilic in nature compared with the hydrophobic interaction in E. coli. Finally, the interaction between τ3 and the replicative helicase DnaB was driven by ATP/Mg2+ conformational changes in DnaB, and evidence is provided that hydrolysis of one ATP molecule by the DnaB hexamer is sufficient to stabilize its interaction with τ3. PMID:23525462
Gadkari, Varun V; Harvey, Sophie R; Raper, Austin T; Chu, Wen-Ting; Wang, Jin; Wysocki, Vicki H; Suo, Zucai
2018-01-01
Abstract Proliferating cell nuclear antigen (PCNA) is a trimeric ring-shaped clamp protein that encircles DNA and interacts with many proteins involved in DNA replication and repair. Despite extensive structural work to characterize the monomeric, dimeric, and trimeric forms of PCNA alone and in complex with interacting proteins, no structure of PCNA in a ring-open conformation has been published. Here, we use a multidisciplinary approach, including single-molecule Förster resonance energy transfer (smFRET), native ion mobility-mass spectrometry (IM-MS), and structure-based computational modeling, to explore the conformational dynamics of a model PCNA from Sulfolobus solfataricus (Sso), an archaeon. We found that Sso PCNA samples ring-open and ring-closed conformations even in the absence of its clamp loader complex, replication factor C, and transition to the ring-open conformation is modulated by the ionic strength of the solution. The IM-MS results corroborate the smFRET findings suggesting that PCNA dynamics are maintained in the gas phase and further establishing IM-MS as a reliable strategy to investigate macromolecular motions. Our molecular dynamic simulations agree with the experimental data and reveal that ring-open PCNA often adopts an out-of-plane left-hand geometry. Collectively, these results implore future studies to define the roles of PCNA dynamics in DNA loading and other PCNA-mediated interactions. PMID:29529283
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Bin; Eliason, William K.; Steitz, Thomas A.
2013-09-19
During the assembly of the bacterial loader-dependent primosome, helicase loader proteins bind to the hexameric helicase ring, deliver it onto the oriC DNA and then dissociate from the complex. Here, to provide a better understanding of this key process, we report the crystal structure of the ~570-kDa prepriming complex between the Bacillus subtilis loader protein and the Bacillus stearothermophilus helicase, as well as the helicase-binding domain of primase with a molar ratio of 6:6:3 at 7.5 Å resolution. The overall architecture of the complex exhibits a three-layered ring conformation. Moreover, the structure combined with the proposed model suggests that themore » shift from the ‘open-ring’ to the ‘open-spiral’ and then the ‘closed-spiral’ state of the helicase ring due to the binding of single-stranded DNA may be the cause of the loader release.« less
Front End Loader Operator. Open Pit Mining Job Training Series.
ERIC Educational Resources Information Center
Savilow, Bill
This training outline for front end loader operators, one in a series of eight outlines, is designed primarily for company training foremen or supervisors and for trainers to use as an industry-wide guideline for heavy equipment operator training in open pit mining in British Columbia. Intended as a guide for preparation of lesson plans both for…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lin, Yen-Chen; Naveen, Vankadari; Molecular Cell Biology, Taiwan International Graduate Program, Institute of Molecular Biology, Academia Sinica, and Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
During DNA replication, bacterial helicase is recruited as a complex in association with loader proteins to unwind the parental duplex. Previous structural studies have reported saturated 6:6 helicase-loader complexes with different conformations. However, structural information on the sub-stoichiometric conformations of these previously-documented helicase-loader complexes remains elusive. Here, with the aid of single particle electron-microscopy (EM) image reconstruction, we present the Geobacillus kaustophilus HTA426 helicase-loader (DnaC-DnaI) complex with a 6:2 binding stoichiometry in the presence of ATPγS. In the 19 Å resolution EM map, the undistorted and unopened helicase ring holds a robust loader density above the C-terminal RecA-like domain. Meanwhile, themore » path of the central DNA binding channel appears to be obstructed by the reconstructed loader density, implying its potential role as a checkpoint conformation to prevent the loading of immature complex onto DNA. Our data also reveals that the bound nucleotides and the consequently induced conformational changes in the helicase hexamer are essential for active association with loader proteins. These observations provide fundamental insights into the formation of the helicase-loader complex in bacteria that regulates the DNA replication process. - Highlights: • Helicase-loader complex structure with 6:2 sub-stoichiometry is resolved by EM. • Helicase hexamer in 6:2 sub-stoichiometry is constricted and un-opened. • 6:2 binding ratio of helicase-loader complex could act as a DNA loading checkpoint. • Nucleotides stabilize helicase-loader complex at low protein concentrations.« less
Parke, Courtney; Tatum, Danielle; Lustig, Arthur J.
2014-01-01
The function of the replication clamp loaders in the semi-conservative telomere replication and their relationship to telomerase- and recombination mechanisms of telomere addition remains ambiguous. We have investigated the variant clamp loader Ctf18 RFC (Replication Factor C). To understand the role of Ctf18 at the telomere, we first investigated genetic interactions after loss of Ctf18 and TLC1 (the yeast telomerase RNA). We find that the tlc1▵ ctf18▵ double mutant confers a rapid >1000-fold decrease in viability. The rate of loss was similar to the kinetics of cell death in rad52▵ tlc1▵ cells. However, the Ctf18 pathway is distinct from Rad52, required for the repair of DSBs, as demonstrated by the synthetic lethality of rad52▵ tlc1▵ ctf18▵ triple mutants. These data suggest that each mutant elicits non-redundant defects acting on the same substrate. Second, interactions of the yeast hyper-recombinational mutant, mre11A470T, with ctf18▵ confer a synergistic cold sensitivity. The phenotype of these double mutants ultimately results in telomere loss and the generation of recombinational survivors. We observed a similar synergism between single mutants that led to hypersensitivity to the DNA alkylating agent, methane methyl sulphonate (MMS), the replication fork inhibitor hydroxyurea (HU), and to a failure to separate telomeres of sister chromatids. Hence, ctf18▵ and mre11A470T act in different pathways on telomere substrates for multiple phenotypes. The mre11A470T cells also displayed a DNA damage response (DDR) at 15°C but not at 30°C while ctf18▵ mutants conferred a constitutive DDR activity. Both the 15°C DDR pattern and growth rate were reversible at 30°C and displayed telomerase activity in vivo. We hypothesize that Ctf18 confers protection against stalling and/or breaks at the replication fork in cells that either lack, or are compromised for, telomerase activity. This Ctf18-based function is likely to contribute another level to telomere size homeostasis. PMID:24533124
Structure and Biochemical Activities of Escherichia coli MgsA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Page, Asher N.; George, Nicholas P.; Marceau, Aimee H.
2012-02-27
Bacterial 'maintenance of genome stability protein A' (MgsA) and related eukaryotic enzymes play important roles in cellular responses to stalled DNA replication processes. Sequence information identifies MgsA enzymes as members of the clamp loader clade of AAA{sup +} proteins, but structural information defining the family has been limited. Here, the x-ray crystal structure of Escherichia coli MgsA is described, revealing a homotetrameric arrangement for the protein that distinguishes it from other clamp loader clade AAA{sup +} proteins. Each MgsA protomer is composed of three elements as follows: ATP-binding and helical lid domains (conserved among AAA{sup +} proteins) and a tetramerizationmore » domain. Although the tetramerization domains bury the greatest amount of surface area in the MgsA oligomer, each of the domains participates in oligomerization to form a highly intertwined quaternary structure. Phosphate is bound at each AAA{sup +} ATP-binding site, but the active sites do not appear to be in a catalytically competent conformation due to displacement of Arg finger residues. E. coli MgsA is also shown to form a complex with the single-stranded DNA-binding protein through co-purification and biochemical studies. MgsA DNA-dependent ATPase activity is inhibited by single-stranded DNA-binding protein. Together, these structural and biochemical observations provide insights into the mechanisms of MgsA family AAA{sup +} proteins.« less
Structure and Biochemical Activities of Escherichia coli MgsA*♦
Page, Asher N.; George, Nicholas P.; Marceau, Aimee H.; Cox, Michael M.; Keck, James L.
2011-01-01
Bacterial “maintenance of genome stability protein A” (MgsA) and related eukaryotic enzymes play important roles in cellular responses to stalled DNA replication processes. Sequence information identifies MgsA enzymes as members of the clamp loader clade of AAA+ proteins, but structural information defining the family has been limited. Here, the x-ray crystal structure of Escherichia coli MgsA is described, revealing a homotetrameric arrangement for the protein that distinguishes it from other clamp loader clade AAA+ proteins. Each MgsA protomer is composed of three elements as follows: ATP-binding and helical lid domains (conserved among AAA+ proteins) and a tetramerization domain. Although the tetramerization domains bury the greatest amount of surface area in the MgsA oligomer, each of the domains participates in oligomerization to form a highly intertwined quaternary structure. Phosphate is bound at each AAA+ ATP-binding site, but the active sites do not appear to be in a catalytically competent conformation due to displacement of Arg finger residues. E. coli MgsA is also shown to form a complex with the single-stranded DNA-binding protein through co-purification and biochemical studies. MgsA DNA-dependent ATPase activity is inhibited by single-stranded DNA-binding protein. Together, these structural and biochemical observations provide insights into the mechanisms of MgsA family AAA+ proteins. PMID:21297161
Assessing musculoskeletal disorders among municipal waste loaders of Mumbai, India.
Salve, Pradeep; Chokhandre, Praveen; Bansod, Dhananjay
2017-10-06
The study aims to assess the impact of municipal waste loading occupation upon developing musculoskeletal disorders (MSDs) and thereby disabilities among waste loaders. Additionally, the study has identified the potential risk factors raising MSDs and disabilities. A cross-sectional case-control design survey was conducted in 6 out of 24 municipal wards of Mumbai during March-September 2015. The study population consisted of municipal waste loaders (N = 180) and a control group (N = 180). The Standardized Modified Nordic questionnaire was adopted to measures the MSDs and thereby disabilities in the past 12 months. A Propensity Score Matching (PSM) method was applied to assess the impact of waste loading occupation on developing MSDs and disabilities. Waste loaders had a significantly higher risk of developing MSDs as well as disabilities than the control group particularly for low back, hip/ thigh upper back and shoulder. Propensity Score Matching results revealed that the MSDs were significantly higher among waste loaders for hip/thigh (22%), low back (19%), shoulder (18%), and upper back (15%) than matched control group. Likewise, MSDs-related disabilities were found to be significantly higher among waste loaders for low back (20%), hip/ thigh (18%) upper back (13%) and shoulder (8%) than the control group. Duration of work, substance use and mental health were found to be the potential psychosocial factors for developing the risk of MSDs and disabilities. The municipal waste loading occupation raised the risk of MSDs and related disabilities among waste loaders compared to the control group. The preventive and curative measures are strongly recommended to minimize the burden of MSDs and disabilities. Int J Occup Med Environ Health 2017;30(6):875-886. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.
Microbiologic contamination during dental radiographic film processing.
Stanczyk, D A; Paunovich, E D; Broome, J C; Fatone, M A
1993-07-01
This study investigated microbiologic contamination of an automatic dental radiograph processor and daylight loader during a week of simulated clinical use. Pure cultures of Candida albicans, Streptococcus pneumoniae, Staphylococcus aureus, or Klebsiella pneumoniae were used to contaminate 320 vinyl intraoral radiograph packets. Each end of the films was deliberately contaminated during opening. These films and 24 uncontaminated control films were processed. Daylight loader ports, inlet and outlet rollers, fixer and developer samples, and 12 processed films were cultured daily. To simulate a weekend, the processor sites were cultured during 72 hours of inactivity after the contaminated runs. The results showed that contamination of the processor and daylight loader occurred and remained even after 48 hours of inactivity. Films remained contaminated after processing. In addition, cross-contamination of films occurred in the processor.
Single-molecule visualization of fast polymerase turnover in the bacterial replisome
Lewis, Jacob S; Spenkelink, Lisanne M; Jergic, Slobodan; Wood, Elizabeth A; Monachino, Enrico; Horan, Nicholas P; Duderstadt, Karl E; Cox, Michael M; Robinson, Andrew; Dixon, Nicholas E; van Oijen, Antoine M
2017-01-01
The Escherichia coli DNA replication machinery has been used as a road map to uncover design rules that enable DNA duplication with high efficiency and fidelity. Although the enzymatic activities of the replicative DNA Pol III are well understood, its dynamics within the replisome are not. Here, we test the accepted view that the Pol III holoenzyme remains stably associated within the replisome. We use in vitro single-molecule assays with fluorescently labeled polymerases to demonstrate that the Pol III* complex (holoenzyme lacking the β2 sliding clamp), is rapidly exchanged during processive DNA replication. Nevertheless, the replisome is highly resistant to dilution in the absence of Pol III* in solution. We further show similar exchange in live cells containing labeled clamp loader and polymerase. These observations suggest a concentration-dependent exchange mechanism providing a balance between stability and plasticity, facilitating replacement of replisomal components dependent on their availability in the environment. DOI: http://dx.doi.org/10.7554/eLife.23932.001 PMID:28432790
A 3 kbar hydrogen-compatible gas loader for Paris-Edinburgh presses
NASA Astrophysics Data System (ADS)
Klotz, S.; Philippe, J.; Bull, C. L.; Loveday, J. S.; Nelmes, R. J.
2013-03-01
We present a device which allows compressed gases to be loaded into large volume opposed anvils used for high pressure neutron scattering in the multi-10 GPa range. The gases are initially loaded into clamps which can then be inserted into VX-Paris-Edinburgh load frames. The system is compatible with all inert gases as well as hydrogen and permits loading pressures of up to 3 kbar for which most gases have densities close to that of the liquid at ambient pressure. The device should have applications for the study of simple molecular solids as well as for loading gases as pressure-transmitting media.
Cryo-EM structure of a helicase loading intermediate containing ORC–Cdc6–Cdt1–MCM2-7 bound to DNA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sun, Jingchuan; Evrin, Cecile; Samel, Stefan A.
2013-07-14
In eukaryotes, the Cdt1-bound replicative helicase core MCM2-7 is loaded onto DNA by the ORC–Cdc6 ATPase to form a prereplicative complex (pre-RC) with an MCM2-7 double hexamer encircling DNA. Using purified components in the presence of ATP-γS, we have captured in vitro an intermediate in pre-RC assembly that contains a complex between the ORC–Cdc6 and Cdt1–MCM2-7 heteroheptamers called the OCCM. Cryo-EM studies of this 14-subunit complex reveal that the two separate heptameric complexes are engaged extensively, with the ORC–Cdc6 N-terminal AAA+ domains latching onto the C-terminal AAA+ motor domains of the MCM2-7 hexamer. The conformation of ORC–Cdc6 undergoes a concertedmore » change into a right-handed spiral with helical symmetry that is identical to that of the DNA double helix. The resulting ORC–Cdc6 helicase loader shows a notable structural similarity to the replication factor C clamp loader, suggesting a conserved mechanism of action.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heltzel, J.; Scouten Ponticelli, S; Sanders, L
2009-01-01
Sliding clamp proteins topologically encircle DNA and play vital roles in coordinating the actions of various DNA replication, repair, and damage tolerance proteins. At least three distinct surfaces of the Escherichia coli {beta} clamp interact physically with the DNA that it topologically encircles. We utilized mutant {beta} clamp proteins bearing G66E and G174A substitutions ({beta}159), affecting the single-stranded DNA-binding region, or poly-Ala substitutions in place of residues 148-HQDVR-152 ({beta}148-152), affecting the double-stranded DNA binding region, to determine the biological relevance of clamp-DNA interactions. As part of this work, we solved the X-ray crystal structure of {beta}148-152, which verified that themore » poly-Ala substitutions failed to significantly alter the tertiary structure of the clamp. Based on functional assays, both {beta}159 and {beta}148-152 were impaired for loading and retention on a linear primed DNA in vitro. In the case of {beta}148-152, this defect was not due to altered interactions with the DnaX clamp loader, but rather was the result of impaired {beta}148-152-DNA interactions. Once loaded, {beta}148-152 was proficient for DNA polymerase III (Pol III) replication in vitro. In contrast, {beta}148-152 was severely impaired for Pol II and Pol IV replication and was similarly impaired for direct physical interactions with these Pols. Despite its ability to support Pol III replication in vitro, {beta}148-152 was unable to support viability of E. coli. Nevertheless, physiological levels of {beta}148-152 expressed from a plasmid efficiently complemented the temperature-sensitive growth phenotype of a strain expressing {beta}159 (dnaN159), provided that Pol II and Pol IV were inactivated. Although this strain was impaired for Pol V-dependent mutagenesis, inactivation of Pol II and Pol IV restored the Pol V mutator phenotype. Taken together, these results support a model in which a sophisticated combination of competitive clamp-DNA, clamp-partner, and partner-DNA interactions serve to manage the actions of the different E. coli Pols in vivo.« less
NASA Technical Reports Server (NTRS)
Clark, K. H. (Inventor)
1983-01-01
A clamp-mount device is disclosed for mounting equipment to an associated I-beam and the like structural member of the type having oppositely extending flanges wherein the device comprises a base and a pair of oppositely facing clamping members carried diagonally on the base clamping flanges therebetween and having flange receiving openings facing one another. Lock means are carried diagonally by the base opposite the clamping members locking the flanges in the clamping members. A resilient hub is carried centrally of the base engaging and biasing a back side of the flanges maintaining tightly clamped and facilitating use on vertical as well as horizontal members. The base turns about the hub to receive the flanges within the clamping members. Equipment may be secured to the base by any suitable means such as bolts in openings. Slidable gate latches secure the hinged locks in an upright locking position. The resilient hub includes a recess opening formed in the base and a rubber-like pad carried in this opening being depressably and rotatably carried therein.
Dickson, Richard K.
2010-09-07
A quick insert and release laser beam guard panel clamping apparatus having a base plate mountable on an optical table, a first jaw affixed to the base plate, and a spring-loaded second jaw slidably carried by the base plate to exert a clamping force. The first and second jaws each having a face acutely angled relative to the other face to form a V-shaped, open channel mouth, which enables wedge-action jaw separation by and subsequent clamping of a laser beam guard panel inserted through the open channel mouth. Preferably, the clamping apparatus also includes a support structure having an open slot aperture which is positioned over and parallel with the open channel mouth.
NASA Astrophysics Data System (ADS)
Kun, Mete; Topaloǧlu, Şeyda; Malli, Tahir
2013-03-01
The marble mining in Turkey has been rising since the early 80's. In relation to that, the marble income has become noticeably bigger than those of other mining sectors. In recent years, marble and natural stone export composes half of the total mine export with a value of two billion dollars. This rapid development observed in marble operation has increased the importance of mining economics, income-expenditure balance and cost analysis. The most important cost elements observed in marble quarrying are machinery and equipment, labor costs and geological structures of the field. The aim of this study is to is to propose a multi-criteria decision making (MCDM) approach to evaluate the wheel loader alternatives and select the best loader under multiple criteria. A two-step methodology based on two MCDM methods, which are namely the Analytic Hierarchy Process (AHP) and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), are used in the evaluation procedure. More precisely, AHP is applied to determine the relative weights of evaluation criteria and TOPSIS is applied to rank the wheel loader alternatives. The proposed approach also provides a relatively simple and very well suited decision making tool for this type of decision making problems.
Open-access microfluidic patch-clamp array with raised lateral cell trapping sites.
Lau, Adrian Y; Hung, Paul J; Wu, Angela R; Lee, Luke P
2006-12-01
A novel open-access microfluidic patch-clamp array chip with lateral cell trapping sites raised above the bottom plane of the chip was developed by combining both a microscale soft-lithography and a macroscale polymer fabrication method. This paper demonstrates the capability of using such an open-access fluidic system for patch-clamp measurements. The surface of the open-access patch-clamp sites prepared by the macroscale hole patterning method of soft-state elastic polydimethylsiloxane (PDMS) is examined; the seal resistances are characterized and correlated with the aperture dimensions. Whole cell patch-clamp measurements are carried out with CHO cells expressing Kv2.1 ion channels. Kv2.1 ion channel blocker (TEA) dosage response is characterized and the binding activity is examined. The results demonstrate that the system is capable of performing whole cell measurements and drug profiling in a more efficient manner than the traditional patch-clamp set-up.
Duchi, Diego; Mazumder, Abhishek; Malinen, Anssi M; Ebright, Richard H; Kapanidis, Achillefs N
2018-06-06
RNA polymerase (RNAP) contains a mobile structural module, the 'clamp,' that forms one wall of the RNAP active-center cleft and that has been linked to crucial aspects of the transcription cycle, including promoter melting, transcription elongation complex stability, transcription pausing, and transcription termination. Using single-molecule FRET on surface-immobilized RNAP molecules, we show that the clamp in RNAP holoenzyme populates three distinct conformational states and interconvert between these states on the 0.1-1 s time-scale. Similar studies confirm that the RNAP clamp is closed in open complex (RPO) and in initial transcribing complexes (RPITC), including paused initial transcribing complexes, and show that, in these complexes, the clamp does not exhibit dynamic behaviour. We also show that, the stringent-response alarmone ppGpp, which reprograms transcription during amino acid starvation stress, selectively stabilizes the partly-closed-clamp state and prevents clamp opening; these results raise the possibility that ppGpp controls promoter opening by modulating clamp dynamics.
Structural Basis of Transcription Inhibition by Fidaxomicin (Lipiarmycin A3).
Lin, Wei; Das, Kalyan; Degen, David; Mazumder, Abhishek; Duchi, Diego; Wang, Dongye; Ebright, Yon W; Ebright, Richard Y; Sineva, Elena; Gigliotti, Matthew; Srivastava, Aashish; Mandal, Sukhendu; Jiang, Yi; Liu, Yu; Yin, Ruiheng; Zhang, Zhening; Eng, Edward T; Thomas, Dennis; Donadio, Stefano; Zhang, Haibo; Zhang, Changsheng; Kapanidis, Achillefs N; Ebright, Richard H
2018-04-05
Fidaxomicin is an antibacterial drug in clinical use for treatment of Clostridium difficile diarrhea. The active ingredient of fidaxomicin, lipiarmycin A3 (Lpm), functions by inhibiting bacterial RNA polymerase (RNAP). Here we report a cryo-EM structure of Mycobacterium tuberculosis RNAP holoenzyme in complex with Lpm at 3.5-Å resolution. The structure shows that Lpm binds at the base of the RNAP "clamp." The structure exhibits an open conformation of the RNAP clamp, suggesting that Lpm traps an open-clamp state. Single-molecule fluorescence resonance energy transfer experiments confirm that Lpm traps an open-clamp state and define effects of Lpm on clamp dynamics. We suggest that Lpm inhibits transcription by trapping an open-clamp state, preventing simultaneous interaction with promoter -10 and -35 elements. The results account for the absence of cross-resistance between Lpm and other RNAP inhibitors, account for structure-activity relationships of Lpm derivatives, and enable structure-based design of improved Lpm derivatives. Copyright © 2018 Elsevier Inc. All rights reserved.
RNA polymerase pausing and nascent RNA structure formation are linked through clamp domain movement
Hein, Pyae P.; Kolb, Kellie E.; Windgassen, Tricia; Bellecourt, Michael J.; Darst, Seth A.; Mooney, Rachel A.; Landick, Robert
2014-01-01
The rates of RNA synthesis and nascent RNA folding into biologically active structures are linked via pausing by RNA polymerase (RNAP). Structures that form within the RNA exit channel can increase pausing by interacting with bacterial RNAP or decrease pausing by preventing backtracking. Conversely, pausing is required for proper folding of some RNAs. Opening of the RNAP clamp domain is proposed to mediate some effects of nascent RNA structures. However, the connections among RNA structure formation, clamp movement, and catalytic activity remain uncertain. We assayed exit-channel structure formation in Escherichia coli RNAP together with disulfide crosslinks that favor closed or open clamp conformations and found that clamp position directly influences RNA structure formation and catalytic activity. We report that exit-channel RNA structures slow pause escape by favoring clamp opening and through interactions with the flap that slow translocation. PMID:25108353
Cable clamp bolt fixture facilitates assembly in close quarters
NASA Technical Reports Server (NTRS)
Sunderland, G. H.
1967-01-01
Cable clamp bolt holding fixture facilitates forming of electrical cable runs in limited equipment space. The fixture engages the threads of the short clamp bolt through the clamp and maintains tension against clamp tendency to open while the operator installs the nut without difficulty.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fiscor, S.
2007-02-15
Operator comfort and serviceability remain important features of front-end loaders or wheel loaders. The article reports on features of the latest large loaders from three companies: Caterpillar (the 992G and 994F), Komatsu (the WA800-3, WA900-3 and WA1200-3), and Le Tourneau (the L-950, L-1350, L-1850 and L-2350). 1 tab., 4 photos.
Seismic explosive charge loader and anchor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mcreynolds, O.B.
1981-07-14
An improved seismic explosive charge loader and anchor for loading and anchoring explosives in cylindrical containers in bore holes is disclosed, which includes a snap in spring band shaped anchor which effectively anchors the loader in the well bore against upward movement, one aspect of the invention includes a snap lock threaded connection for securing an explosive container having interrupted threads to the loader and anchor, and the loader and anchor is constructed and arranged to maintain a detonator in place in the explosive container thereby assuring detonation of the explosive.
Assessment of respirable dust and its free silica contents in different Indian coalmines.
Mukherjee, Ashit K; Bhattacharya, Sanat K; Saiyed, Habibullah N
2005-04-01
Assessment of respirable dust, personal exposures of miners and free silica contents in dust were undertaken to find out the associated risk of coal workers' pneumoconiosis in 9 coal mines of Eastern India during 1988-91. Mine Research Establishment (MRE), 113A Gravimetric Dust Sampler (GDS) and personal samplers (AFC 123), Cassella, London, approved by Director General of Mines Safety (DGMS) were used respectively for monitoring of mine air dust and personal exposures of miners. Fourier Transform Infra-red (FTIR) Spectroscopy determined free silica in respirable dusts. Thermal Conditions like Wet Bulb Globe Temperature (WBGT) index, humidity and wind velocity were also recorded during monitoring. The dust levels in the face return air of both, Board & Pillar (B&P) and Long Wall (LW) mining were found above the permissible level recommended by DGMS, Govt. of India. The drilling, blasting and loading are the major dusty operations in B&P method. Exposures of driller and loader were varied between, 0.81-9.48 mg/m3 and 0.05-9.84 mg/m3 respectively in B&P mining, whereas exposures of DOSCO loader, Shearer operator and Power Support Face Worker were varied between 2.65-9.11 mg/m3, 0.22-10.00 mg/m3 and 0.12-9.32 mg/m3 respectively in LW mining. In open cast mining, compressor and driller operators are the major exposed groups. The percentage silica in respirable dusts found below 5% in all most all the workers except among query loaders and drillers of open cast mines.
Extracting whole short rotation trees with a skidder and a front-end loader
R. Spinelli; B.R. Hartsough
2001-01-01
We time-studied a Caterpillar 950F front-end loader and a Caterpillar 528 grapple skidder used to extract bunched whole trees to a landing in a short rotation Eucalyptus plantation. The loader was 40-60% more productive than the grapple skidder, depending on extraction distance. Alternatively, the single loader could both extract trees and handle the landing duties,...
EPA Nonregulatory Nonroad Duty Cycles
EPA nonregulatory, nonroad duty cycles for equipment such as agricultural tractors, backhoe loaders,crawlers tractors, excavators, arc welding skid steer loaders, and wheel loaders. Also,test procedures, laboratory methods, and emissions for this equipmen
Kazlauskas, Darius; Krupovic, Mart; Venclovas, Česlovas
2016-01-01
Abstract Genomic DNA replication is a complex process that involves multiple proteins. Cellular DNA replication systems are broadly classified into only two types, bacterial and archaeo-eukaryotic. In contrast, double-stranded (ds) DNA viruses feature a much broader diversity of DNA replication machineries. Viruses differ greatly in both completeness and composition of their sets of DNA replication proteins. In this study, we explored whether there are common patterns underlying this extreme diversity. We identified and analyzed all major functional groups of DNA replication proteins in all available proteomes of dsDNA viruses. Our results show that some proteins are common to viruses infecting all domains of life and likely represent components of the ancestral core set. These include B-family polymerases, SF3 helicases, archaeo-eukaryotic primases, clamps and clamp loaders of the archaeo-eukaryotic type, RNase H and ATP-dependent DNA ligases. We also discovered a clear correlation between genome size and self-sufficiency of viral DNA replication, the unanticipated dominance of replicative helicases and pervasive functional associations among certain groups of DNA replication proteins. Altogether, our results provide a comprehensive view on the diversity and evolution of replication systems in the DNA virome and uncover fundamental principles underlying the orchestration of viral DNA replication. PMID:27112572
Development of an electric, battery powered, skid-steer loader
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alcock, R.; Froehlich, D.P.; Christianson, L.L.
1985-01-01
A battery powered, skid-steer loader was developed for farm chore routines and materials handling activities. Outlined are details on drive train, hydraulics, loader, frame, cab, controls, battery and controller. Preliminary performance characteristics of the hydraulics are presented.
Automatic Vetting for Malice in Android Platforms
2016-05-01
be distinguished. For example, both Face- book and Instagram ship a class named Landroid/support/v4/app/Fragment;§ with different method signatures...relationships (e.g., Lcom/ instagram /.../LoadImageTask; is a sub- class of the abstract class Landroid/os/AsyncTask;). Figure 2(c) displays a method graph...7feaf7c75a5305b1083a160f...baa6.dex.dex parent_loader 3 Instagram instagram_classes.dex parent_loader 4 JohnNESLite johnneslite_classes.dex parent_loader (a) Class Loader
The causes and control of loader- and truck-related fatalities in surface mining operations.
Kecojevic, Vladislav; Radomsky, Mark
2004-12-01
At surface mining operations throughout the world, loaders and trucks are a primary means of material loading and haulage. As the size, use and technological complexity of these units have increased, so has the concern regarding loader and truck safety. The severity and number of accidents involving loaders and trucks is higher when compared to all other mining accident types. In this paper, an analysis of loader and truck-related fatalities over the last 8 years is performed, the fatality categories and causes of accidents are established and control strategies are discussed and evaluated in an effort to increase hazard awareness by emphasizing safe loading, hauling and maintenance practices, as well as the value of traditional and innovative miner training programmes.
Compilation of load spectrum of loader drive axle
NASA Astrophysics Data System (ADS)
Wei, Yongxiang; Zhu, Haoyue; Tang, Heng; Yuan, Qunwei
2018-03-01
In order to study the preparation method of gear fatigue load spectrum for loaders, the load signal of four typical working conditions of loader is collected. The signal that reflects the law of load change is obtained by preprocessing the original signal. The torque of the drive axle is calculated by using the rain flow counting method. According to the operating time ratio of each working condition, the two dimensional load spectrum based on the real working conditions of the drive axle of loader is established by the cycle extrapolation and synthesis method. The two-dimensional load spectrum is converted into one-dimensional load spectrum by means of the mean of torque equal damage method. Torque amplification includes the maximum load torque of the main reduction gear. Based on the theory of equal damage, the accelerated cycles are calculated. In this way, the load spectrum of the loading condition of the drive axle is prepared to reflect loading condition of the loader. The load spectrum can provide reference for fatigue life test and life prediction of loader drive axle.
Kazlauskas, Darius; Krupovic, Mart; Venclovas, Česlovas
2016-06-02
Genomic DNA replication is a complex process that involves multiple proteins. Cellular DNA replication systems are broadly classified into only two types, bacterial and archaeo-eukaryotic. In contrast, double-stranded (ds) DNA viruses feature a much broader diversity of DNA replication machineries. Viruses differ greatly in both completeness and composition of their sets of DNA replication proteins. In this study, we explored whether there are common patterns underlying this extreme diversity. We identified and analyzed all major functional groups of DNA replication proteins in all available proteomes of dsDNA viruses. Our results show that some proteins are common to viruses infecting all domains of life and likely represent components of the ancestral core set. These include B-family polymerases, SF3 helicases, archaeo-eukaryotic primases, clamps and clamp loaders of the archaeo-eukaryotic type, RNase H and ATP-dependent DNA ligases. We also discovered a clear correlation between genome size and self-sufficiency of viral DNA replication, the unanticipated dominance of replicative helicases and pervasive functional associations among certain groups of DNA replication proteins. Altogether, our results provide a comprehensive view on the diversity and evolution of replication systems in the DNA virome and uncover fundamental principles underlying the orchestration of viral DNA replication. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.
NASA Technical Reports Server (NTRS)
Vest, Thomas W. (Inventor); Carden, James R. (Inventor); Norton, William E. (Inventor); Belcher, Jewell G. (Inventor)
1992-01-01
A prosthetic device for below-the-elbow amputees, having a C-shaped clamping mechanism for grasping cylindrical objects, is described. The clamping mechanism is pivotally mounted to a cuff that fits on the amputee's lower arm. The present invention is utilized by placing an arm that has been amputated below the elbow into the cuff. The clamping mechanism then serves as a hand whenever it becomes necessary for the amputee to grasp a cylindrical object such as a handle, a bar, a rod, etc. To grasp the cylindrical object, the object is jammed against the opening in the C-shaped spring, causing the spring to open, the object to pass to the center of the spring, and the spring to snap shut behind the object. Various sizes of clamping mechanisms can be provided and easily interchanged to accommodate a variety of diameters. With the extension that pivots and rotates, the clamping mechanism can be used in a variety of orientations. Thus, this invention provides the amputee with a clamping mechanism that can be used to perform a number of tasks.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gress, A.V. Jr.
1985-08-21
At the investigation of Sandia Albuquerque, a semiautomatic powder loader was designed and fabricated for pyrotechnics devices. The basic functions of the system were to load a precise, measured amount of powder into a charge holder and to compact the mixture to a specified density. This report documents the history, rationale, design, and performance of the Mod 1 loader.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hood, Iris V.; Berger, James M.
Replisome assembly requires the loading of replicative hexameric helicases onto origins by AAA+ ATPases. How loader activity is appropriately controlled remains unclear. Here, we use structural and biochemical analyses to establish how an antimicrobial phage protein interferes with the function of theStaphylococcus aureusreplicative helicase loader, DnaI. The viral protein binds to the loader’s AAA+ ATPase domain, allowing binding of the host replicative helicase but impeding loader self-assembly and ATPase activity. Close inspection of the complex highlights an unexpected locus for the binding of an interdomain linker element in DnaI/DnaC-family proteins. We find that the inhibitor protein is genetically coupled tomore » a phage-encoded homolog of the bacterial helicase loader, which we show binds to the host helicase but not to the inhibitor itself. These findings establish a new approach by which viruses can hijack host replication processes and explain how loader activity is internally regulated to prevent aberrant auto-association.« less
Determination of Critical Rock Mass in a Bucket of a Dinting Loader
NASA Astrophysics Data System (ADS)
Remiorz, Eryk
2017-09-01
The extraction of hard coal deposits lying in increasing depth causes significant problems with maintenance of roadways (maingates, tailgates, etc.). The reduction of the cross section of such excavations, caused by the floor upheaval, leads to the occurrence of many problems with transport and ventilation. Dinting loaders are employed to restore the original size of roadways tightened due to the activity of adverse stresses occurring in the rock mass. These are tracked machines, usually with small width of about 1 m. They often work in roadways with high longitudinal and lateral inclination, as a result of which they are especially susceptible to overturning. The article presents a mathematical model allowing to determine the critical mass of broken rock in a bucket. The model also allows to determine spatial coordinates of a dinting loader's centre of gravity depending on temporary position of movable elements of the loader such as a turntable, boom, coupler and bucket, and depending on the level of loading the bucket with broken rock. It also enables to determine critical angles of the roadways' longitudinal and lateral inclination. The outcomes of computer studies of variations in the position of the loader's centre of gravity depending on deflection angles of moving elements of the loader and the mass of broken rock in the bucket are also presented. Variability ranges of spatial coordinates of the centre of gravity of the loader are also established and examples are given for values of the critical mass of broken rock in the bucket.
A Transfer of Training Study of Control Loader Dynamics
NASA Technical Reports Server (NTRS)
Cardullo, Frank M.; Stanco, Anthony A.; Kelly, Lon C.; Houck, Jacob A.; Grube, Richard C.
2011-01-01
The control inceptor used in a simulated vehicle is an important part in maintaining the fidelity of a simulation. The force feedback provided by the control inceptor gives the operator important cues to maintain adequate performance. The dynamics of a control inceptor are typically based on a second order spring mass damper system with damping, force gradient, breakout force, and natural frequency parameters. Changing these parameters can have a great effect on pilot or driver control of the vehicle. The neuromuscular system has a very important role in manipulating the control inceptor within a vehicle. Many studies by McRuer, Aponso, and Hess have dealt with modeling the neuromuscular system and quantifying the effects of a high fidelity control loader as compared to a low fidelity control loader. Humans are adaptive in nature and their control behavior changes based on different control loader dynamics. Humans will change their control behavior to maintain tracking bandwidth and minimize tracking error. This paper reports on a quasi-transfer of training experiment which was performed at the NASA Langley Research Center. The quasi transfer of training study used a high fidelity control loader and a low fidelity control loader. Subjects trained in both simulations and then were transferred to the high fidelity control loader simulation. The parameters for the high fidelity control loader were determined from the literature. The low fidelity control loader parameters were found through testing of a simple computer joystick. A disturbance compensatory task is employed. The compensatory task involves implementing a simple horizon out the window display. A disturbance consisting of a sum of sines is used. The task consists of the subject compensating for the disturbance on the roll angle of the aircraft. The vehicle dynamics are represented as 1/s and 1/s2. The subject will try to maintain level flight throughout the experiment. The subjects consist of non-pilots to remove any effects of pilot experience. First, this paper discusses the implementation of the disturbance compensation task. Second, the high and low fidelity parameters used within the experiment are presented. Finally, an explanation of results from the experiments is presented.
Ontology-Based Method for Fault Diagnosis of Loaders.
Xu, Feixiang; Liu, Xinhui; Chen, Wei; Zhou, Chen; Cao, Bingwei
2018-02-28
This paper proposes an ontology-based fault diagnosis method which overcomes the difficulty of understanding complex fault diagnosis knowledge of loaders and offers a universal approach for fault diagnosis of all loaders. This method contains the following components: (1) An ontology-based fault diagnosis model is proposed to achieve the integrating, sharing and reusing of fault diagnosis knowledge for loaders; (2) combined with ontology, CBR (case-based reasoning) is introduced to realize effective and accurate fault diagnoses following four steps (feature selection, case-retrieval, case-matching and case-updating); and (3) in order to cover the shortages of the CBR method due to the lack of concerned cases, ontology based RBR (rule-based reasoning) is put forward through building SWRL (Semantic Web Rule Language) rules. An application program is also developed to implement the above methods to assist in finding the fault causes, fault locations and maintenance measures of loaders. In addition, the program is validated through analyzing a case study.
Ontology-Based Method for Fault Diagnosis of Loaders
Liu, Xinhui; Chen, Wei; Zhou, Chen; Cao, Bingwei
2018-01-01
This paper proposes an ontology-based fault diagnosis method which overcomes the difficulty of understanding complex fault diagnosis knowledge of loaders and offers a universal approach for fault diagnosis of all loaders. This method contains the following components: (1) An ontology-based fault diagnosis model is proposed to achieve the integrating, sharing and reusing of fault diagnosis knowledge for loaders; (2) combined with ontology, CBR (case-based reasoning) is introduced to realize effective and accurate fault diagnoses following four steps (feature selection, case-retrieval, case-matching and case-updating); and (3) in order to cover the shortages of the CBR method due to the lack of concerned cases, ontology based RBR (rule-based reasoning) is put forward through building SWRL (Semantic Web Rule Language) rules. An application program is also developed to implement the above methods to assist in finding the fault causes, fault locations and maintenance measures of loaders. In addition, the program is validated through analyzing a case study. PMID:29495646
The effect of fragmentation on loader productivity
DOE Office of Scientific and Technical Information (OSTI.GOV)
McGill, M.D.; Freadrich, J.
1994-12-31
There are many factors which affect the productivity of a front end loader. One of the most obvious is the characteristics of the material being mined. Characteristics such as size distribution, swell factor or heave, and material hardness/abrasiveness will all effect the efficiency of the mucking cycle. The focus of this paper is to look specifically at the size distribution of blasted material, and quantify the effects on loader productivity.
Comparison of a Skidder and Front-End Loader for Primary Transport of Short-Rotation Trees
Raffaele Spinelli; Bruce R. Hartsough
1999-01-01
We time-studied a Cat 950F and a Cat 528 grapple skidder as extraction devices for moving bunched whole trees to a landing in a short rotation eucalyptus plantation. The front-end loader was 40 to 60% more productive than the grapple skidder, depending on extraction distance. Alternatively, the single loader could both extract trees and handle the landing duties such...
Detachable clamps for minimal access surgery.
Frank, T; Willetts, G J; Cuschieri, A
1995-01-01
A detachable clamp and applicator have been developed for use in minimal access surgical operations involving hollow visceral transection and anastomosis. The clamp has parallel jaws which ensure uniform distribution of the occlusive force. Following application on the bowel, the clamp is released from the applicator, thus freeing the access port. On completion of the anastomosis, the clamp is docked to the applicator, its jaws opened for release from the bowel and then closed prior to removal. The jaws of the clamp are kept closed by a pseudoelastic nickel-titanium (NiTi) alloy spring which imparts advantageous force characteristics when compared to stainless steel. The excellent holding and atraumatic characteristics of the detachable clamp have been confirmed by use in laparoscopic and thoracoscopic surgery on the gastrointestinal tract.
Structure of the active form of human origin recognition complex and its ATPase motor module
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tocilj, Ante; On, Kin Fan; Yuan, Zuanning
Binding of the Origin Recognition Complex (ORC) to origins of replication marks the first step in the initiation of replication of the genome in all eukaryotic cells. Here, we report the structure of the active form of human ORC determined by X-ray crystallography and cryo-electron microscopy. The complex is composed of an ORC1/4/5 motor module lobe in an organization reminiscent of the DNA polymerase clamp loader complexes. A second lobe contains the ORC2/3 subunits. The complex is organized as a double-layered shallow corkscrew, with the AAA+ and AAA+-like domains forming one layer, and the winged-helix domains (WHDs) forming a topmore » layer. CDC6 fits easily between ORC1 and ORC2, completing the ring and the DNA-binding channel, forming an additional ATP hydrolysis site. Analysis of the ATPase activity of the complex provides a basis for understanding ORC activity as well as molecular defects observed in Meier-Gorlin Syndrome mutations.« less
Khair, Lyne; Chang, Ya-Ting; Subramanian, Lakxmi; Russell, Paul; Nakamura, Toru M
2010-06-01
While telomeres must provide mechanisms to prevent DNA repair and DNA damage checkpoint factors from fusing chromosome ends and causing permanent cell cycle arrest, these factors associate with functional telomeres and play critical roles in the maintenance of telomeres. Previous studies have established that Tel1 (ATM) and Rad3 (ATR) kinases play redundant but essential roles for telomere maintenance in fission yeast. In addition, the Rad9-Rad1-Hus1 (911) and Rad17-RFC complexes work downstream of Rad3 (ATR) in fission yeast telomere maintenance. Here, we investigated how 911, Rad17-RFC and another RFC-like complex Ctf18-RFC contribute to telomere maintenance in fission yeast cells lacking Tel1 and carrying a novel hypomorphic allele of rad3 (DBD-rad3), generated by the fusion between the DNA binding domain (DBD) of the fission yeast telomere capping protein Pot1 and Rad3. Our investigations have uncovered a surprising redundancy for Rad9 and Hus1 in allowing Rad1 to contribute to telomere maintenance in DBD-rad3 tel1 cells. In addition, we found that Rad17-RFC and Ctf18-RFC carry out redundant telomere maintenance functions in DBD-rad3 tel1 cells. Since checkpoint sensor proteins are highly conserved, genetic redundancies uncovered here may be relevant to telomere maintenance and detection of DNA damage in other eukaryotes.
Khair, Lyne; Chang, Ya-Ting; Subramanian, Lakxmi; Russell, Paul; Nakamura, Toru M.
2011-01-01
While telomeres must provide mechanisms to prevent DNA repair and DNA damage checkpoint factors from fusing chromosome ends and causing permanent cell cycle arrest, these factors associate with functional telomeres and play critical roles in the maintenance of telomeres. Previous studies have established that Tel1 (ATM) and Rad3 (ATR) kinases play redundant but essential roles for telomere maintenance in fission yeast. In addition, the Rad9-Rad1-Hus1 (911) and Rad17-RFC complexes work downstream of Rad3 (ATR) in fission yeast telomere maintenance. Here, we investigated how 911, Rad17-RFC and another RFC-like complex Ctf18-RFC contribute to telomere maintenance in fission yeast cells lacking Tel1 and carrying a novel hypomorphic allele of rad3 (DBD-rad3), generated by the fusion between the DNA binding domain (DBD) of the fission yeast telomere capping protein Pot1 and Rad3. Our investigations have uncovered a surprising redundancy for Rad9 and Hus1 in allowing Rad1 to contribute to telomere maintenance in DBD-rad3 tel1Δ cells. In addition, we found that Rad17-RFC and Ctf18-RFC carry out redundant telomere maintenance functions in DBD-rad3 tel1Δ cells. Since checkpoint sensor proteins are highly conserved, genetic redundancies uncovered here may be relevant to telomere maintenance and detection of DNA damage in other eukaryotes. PMID:20505337
Zhu, Qingyuan; Xiao, Chunsheng; Hu, Huosheng; Liu, Yuanhui; Wu, Jinjin
2018-01-13
Articulated wheel loaders used in the construction industry are heavy vehicles and have poor stability and a high rate of accidents because of the unpredictable changes of their body posture, mass and centroid position in complex operation environments. This paper presents a novel distributed multi-sensor system for real-time attitude estimation and stability measurement of articulated wheel loaders to improve their safety and stability. Four attitude and heading reference systems (AHRS) are constructed using micro-electro-mechanical system (MEMS) sensors, and installed on the front body, rear body, rear axis and boom of an articulated wheel loader to detect its attitude. A complementary filtering algorithm is deployed for sensor data fusion in the system so that steady state margin angle (SSMA) can be measured in real time and used as the judge index of rollover stability. Experiments are conducted on a prototype wheel loader, and results show that the proposed multi-sensor system is able to detect potential unstable states of an articulated wheel loader in real-time and with high accuracy.
Xiao, Chunsheng; Liu, Yuanhui; Wu, Jinjin
2018-01-01
Articulated wheel loaders used in the construction industry are heavy vehicles and have poor stability and a high rate of accidents because of the unpredictable changes of their body posture, mass and centroid position in complex operation environments. This paper presents a novel distributed multi-sensor system for real-time attitude estimation and stability measurement of articulated wheel loaders to improve their safety and stability. Four attitude and heading reference systems (AHRS) are constructed using micro-electro-mechanical system (MEMS) sensors, and installed on the front body, rear body, rear axis and boom of an articulated wheel loader to detect its attitude. A complementary filtering algorithm is deployed for sensor data fusion in the system so that steady state margin angle (SSMA) can be measured in real time and used as the judge index of rollover stability. Experiments are conducted on a prototype wheel loader, and results show that the proposed multi-sensor system is able to detect potential unstable states of an articulated wheel loader in real-time and with high accuracy. PMID:29342850
Fuelcell-Hybrid Mine loader (LHD)
DOE Office of Scientific and Technical Information (OSTI.GOV)
James L Dippo; Tim Erikson; Kris Hess
2009-07-10
The fuel cell hybrid mine loader project, sponsored by a government-industry consortium, was implemented to determine the viability of proton exchange membrane (PEM) fuel cells in underground mining applications. The Department of Energy (DOE) sponsored this project with cost-share support from industry. The project had three main goals: (1) to develop a mine loader powered by a fuel cell, (2) to develop associated metal-hydride storage and refueling systems, and (3) to demonstrate the fuel cell hybrid loader in an underground mine in Nevada. The investigation of a zero-emissions fuel cell power plant, the safe storage of hydrogen, worker health advantagesmore » (over the negative health effects associated with exposure to diesel emissions), and lower operating costs are all key objectives for this project.« less
Code of Federal Regulations, 2014 CFR
2014-07-01
... particular piece of equipment. Front-end loaders shall be tested with the loader bucket empty. Equipment... speed the equipment is traveling except for equipment which is designed for the power train to be...
Code of Federal Regulations, 2011 CFR
2011-07-01
... particular piece of equipment. Front-end loaders shall be tested with the loader bucket empty. Equipment... speed the equipment is traveling except for equipment which is designed for the power train to be...
Code of Federal Regulations, 2013 CFR
2013-07-01
... particular piece of equipment. Front-end loaders shall be tested with the loader bucket empty. Equipment... speed the equipment is traveling except for equipment which is designed for the power train to be...
Code of Federal Regulations, 2012 CFR
2012-07-01
... particular piece of equipment. Front-end loaders shall be tested with the loader bucket empty. Equipment... speed the equipment is traveling except for equipment which is designed for the power train to be...
Device for remote operation of electrical disconnect
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coleman, Jody Rustyn; Bobbitt, III, John Thomas
Provided is a device for remote operation of an electrical disconnect. The device can include a handle clamp configured to be secured to an extending member of the electrical disconnect. The device can further include a case clamp configured to be secured to a rigid portion of the electrical disconnect. The device can further include a cable having an exterior sheath coaxially surrounding an inner cable. The inner cable can be coaxially slidable with respect to the exterior sheath. The inner cable can extend through an opening of the case clamp and be secured to the handle clamp. The devicemore » can further include an actuator configured to coaxially slide the inner cable such that the handle clamp is actuated towards the case clamp.« less
Lee, Taein; Cheng, Chun-Huai; Ficklin, Stephen; Yu, Jing; Humann, Jodi; Main, Dorrie
2017-01-01
Abstract Tripal is an open-source database platform primarily used for development of genomic, genetic and breeding databases. We report here on the release of the Chado Loader, Chado Data Display and Chado Search modules to extend the functionality of the core Tripal modules. These new extension modules provide additional tools for (1) data loading, (2) customized visualization and (3) advanced search functions for supported data types such as organism, marker, QTL/Mendelian Trait Loci, germplasm, map, project, phenotype, genotype and their respective metadata. The Chado Loader module provides data collection templates in Excel with defined metadata and data loaders with front end forms. The Chado Data Display module contains tools to visualize each data type and the metadata which can be used as is or customized as desired. The Chado Search module provides search and download functionality for the supported data types. Also included are the tools to visualize map and species summary. The use of materialized views in the Chado Search module enables better performance as well as flexibility of data modeling in Chado, allowing existing Tripal databases with different metadata types to utilize the module. These Tripal Extension modules are implemented in the Genome Database for Rosaceae (rosaceae.org), CottonGen (cottongen.org), Citrus Genome Database (citrusgenomedb.org), Genome Database for Vaccinium (vaccinium.org) and the Cool Season Food Legume Database (coolseasonfoodlegume.org). Database URL: https://www.citrusgenomedb.org/, https://www.coolseasonfoodlegume.org/, https://www.cottongen.org/, https://www.rosaceae.org/, https://www.vaccinium.org/
Code of Federal Regulations, 2014 CFR
2014-07-01
.... Front-end loaders shall be tested with the loader bucket empty. Equipment shall not be tested when... equipment which is designed for the power train to be disengaged during braking. (v) Testing speeds shall be...
Code of Federal Regulations, 2013 CFR
2013-07-01
.... Front-end loaders shall be tested with the loader bucket empty. Equipment shall not be tested when... equipment which is designed for the power train to be disengaged during braking. (v) Testing speeds shall be...
Code of Federal Regulations, 2011 CFR
2011-07-01
.... Front-end loaders shall be tested with the loader bucket empty. Equipment shall not be tested when... equipment which is designed for the power train to be disengaged during braking. (v) Testing speeds shall be...
Code of Federal Regulations, 2012 CFR
2012-07-01
.... Front-end loaders shall be tested with the loader bucket empty. Equipment shall not be tested when... equipment which is designed for the power train to be disengaged during braking. (v) Testing speeds shall be...
Automatic Test, Configuration, and Repair of Cellular Arrays
1975-06-01
one cell to loed any good cell that is not walled off by flawed cells. The loading Information which the computer sends to the array may select one...to loed that cell’s loader and function-specificatioi state bits. After the cell is loaded» it« loader state bits may specify which of the cell’s...Mechanism With Options FUNCTION-SPEC, STATE BITS D.OUT INO INI OUTO 0UT1 LOO LO PAGE 99 LOADER TIP BITS CHANGER ill LSTA S.U.IN S.R.IN
Fabrication and characterization of a piezoelectric energy harvester with clamped-clamped beams
NASA Astrophysics Data System (ADS)
Cui, Yan; Yu, Menglin; Gao, Shiqiao; Kong, Xiangxin; Gu, Wang; Zhang, Ran; Liu, Bowen
2018-05-01
This work presents a piezoelectric energy harvester with clamped-clamped beams, and it is fabricated with MEMS process. When excited by sinusoidal vibration, the energy harvester has a sharp jumping down phenomenon and the measured frequency responses of the clamped-clamped beams structure show a larger bandwidth which is about 56Hz, more efficient than that with cantilever beams. When the exciting acceleration ac is 12m/s2, the energy harvester achieves to a maximum open-circuit voltage of 94mV on one beam. The load voltage is proportional to the load resistance, and it increased with the increase of load resistance. Connected four beams in series, the output power reaches the maximum value of 730 nW and the optimal load is 15KΩ to one beam.
9. PHOTOCOPY, ARCHITECTURAL SECTIONS AND DETAIL DRAWING OF UNDERGROUND STORAGE ...
9. PHOTOCOPY, ARCHITECTURAL SECTIONS AND DETAIL DRAWING OF UNDERGROUND STORAGE MAGAZINES AND LAUNCHER-LOADER ASSEMBLIES. - NIKE Missile Base SL-40, Underground Storage Magazines & Launcher-Loader Assemblies, Southwesternmost end of launch area, Hecker, Monroe County, IL
An abstract class loader for the SSP and its implementation in TL.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wickstrom, Gregory Lloyd; Winter, Victor Lono; Fraij, Fares
2004-08-01
The SSP is a hardware implementation of a subset of the JVM for use in high consequence embedded applications. In this context, a majority of the activities belonging to class loading, as it is defined in the specification of the JVM, can be performed statically. Static class loading has the net result of dramatically simplifying the design of the SSP as well as increasing its performance. Due to the high consequence nature of its applications, strong evidence must be provided that all aspects of the SSP have been implemented correctly. This includes the class loader. This article explores the possibilitymore » of formally verifying a class loader for the SSP implemented in the strategic programming language TL. Specifically, an implementation of the core activities of an abstract class loader is presented and its verification in ACL2 is considered.« less
1917-08-01
To extract a cartridge or a cartridge case, put the rammer in the muzzle of gun and knock with the head of the rammer on the fuse of the projectile...or on the base of the case. If it is a cartridge which is being extracted ! the loader, standing at the breech, receives it in both hands. (f) Give...fuses and charges. They should be tried in the loading position (incline the gun slightly, open the breech gently, and extract the cartridge with
7. PHOTOCOPY, PLUMBING AND MECHANICAL PLAN AND DETAILS FOR UNDERGROUND ...
7. PHOTOCOPY, PLUMBING AND MECHANICAL PLAN AND DETAILS FOR UNDERGROUND STORAGE MAGAZINES AND LAUNCHER-LOADER ASSEMBLIES. - NIKE Missile Base SL-40, Underground Storage Magazines & Launcher-Loader Assemblies, Southwesternmost end of launch area, Hecker, Monroe County, IL
8. PHOTOCOPY, ARCHITECTURAL FLOOR PLAN AND DETAIL DRAWING OF UNDERGROUND ...
8. PHOTOCOPY, ARCHITECTURAL FLOOR PLAN AND DETAIL DRAWING OF UNDERGROUND STORAGE MAGAZINES AND LAUNCHER-LOADER ASSEMBLIES. - NIKE Missile Base SL-40, Underground Storage Magazines & Launcher-Loader Assemblies, Southwesternmost end of launch area, Hecker, Monroe County, IL
Fiber optic to integrated optical chip coupler
NASA Technical Reports Server (NTRS)
Pikulski, Joseph I. (Inventor); Ramer, O. Glenn (Inventor)
1987-01-01
Optical fibers are clamped by a block onto a substrate. Thereupon, metal is plated over the fibers to hold them in place upon the substrate. The clamp block is removed and the opening, resulting from the clamp block's presence, is then plated in. The built-up metallic body is a coupling which holds the fibers in position so that the ends can be polished for coupling to an integrated optical chip upon a coupling fixture.
Code of Federal Regulations, 2010 CFR
2010-01-01
... passenger by other parties. Ground support equipment means service and maintenance equipment used at an airport to support aeronautical operations and related activities. Baggage tugs, belt loaders, cargo loaders, forklifts, fuel trucks, lavatory trucks, and pushback tractors are among the types of vehicles...
Quality control mechanisms exclude incorrect polymerases from the eukaryotic replication fork
Schauer, Grant D.; O’Donnell, Michael E.
2017-01-01
The eukaryotic genome is primarily replicated by two DNA polymerases, Pol ε and Pol δ, that function on the leading and lagging strands, respectively. Previous studies have established recruitment mechanisms whereby Cdc45-Mcm2-7-GINS (CMG) helicase binds Pol ε and tethers it to the leading strand, and PCNA (proliferating cell nuclear antigen) binds tightly to Pol δ and recruits it to the lagging strand. The current report identifies quality control mechanisms that exclude the improper polymerase from a particular strand. We find that the replication factor C (RFC) clamp loader specifically inhibits Pol ε on the lagging strand, and CMG protects Pol ε against RFC inhibition on the leading strand. Previous studies show that Pol δ is slow and distributive with CMG on the leading strand. However, Saccharomyces cerevisiae Pol δ–PCNA is a rapid and processive enzyme, suggesting that CMG may bind and alter Pol δ activity or position it on the lagging strand. Measurements of polymerase binding to CMG demonstrate Pol ε binds CMG with a Kd value of 12 nM, but Pol δ binding CMG is undetectable. Pol δ, like bacterial replicases, undergoes collision release upon completing replication, and we propose Pol δ–PCNA collides with the slower CMG, and in the absence of a stabilizing Pol δ–CMG interaction, the collision release process is triggered, ejecting Pol δ on the leading strand. Hence, by eviction of incorrect polymerases at the fork, the clamp machinery directs quality control on the lagging strand and CMG enforces quality control on the leading strand. PMID:28069954
Structure of the active form of human origin recognition complex and its ATPase motor module
Tocilj, Ante; On, Kin Fan; Yuan, Zuanning; Sun, Jingchuan; Elkayam, Elad; Li, Huilin; Stillman, Bruce; Joshua-Tor, Leemor
2017-01-01
Binding of the Origin Recognition Complex (ORC) to origins of replication marks the first step in the initiation of replication of the genome in all eukaryotic cells. Here, we report the structure of the active form of human ORC determined by X-ray crystallography and cryo-electron microscopy. The complex is composed of an ORC1/4/5 motor module lobe in an organization reminiscent of the DNA polymerase clamp loader complexes. A second lobe contains the ORC2/3 subunits. The complex is organized as a double-layered shallow corkscrew, with the AAA+ and AAA+-like domains forming one layer, and the winged-helix domains (WHDs) forming a top layer. CDC6 fits easily between ORC1 and ORC2, completing the ring and the DNA-binding channel, forming an additional ATP hydrolysis site. Analysis of the ATPase activity of the complex provides a basis for understanding ORC activity as well as molecular defects observed in Meier-Gorlin Syndrome mutations. DOI: http://dx.doi.org/10.7554/eLife.20818.001 PMID:28112645
146. FUEL LINE TO SKID 2 (FUEL LOADER) IN FUEL ...
146. FUEL LINE TO SKID 2 (FUEL LOADER) IN FUEL CONTROL ROOM (215), LSB (BLDG. 751). LIQUID NITROGEN/HELIUM HEAT EXCHANGER ON RIGHT. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA
NASA Technical Reports Server (NTRS)
Becker, Jeffrey C.
1995-01-01
The Thinking Machines CM-5 platform was designed to run single program, multiple data (SPMD) applications, i.e., to run a single binary across all nodes of a partition, with each node possibly operating on different data. Certain classes of applications, such as multi-disciplinary computational fluid dynamics codes, are facilitated by the ability to have subsets of the partition nodes running different binaries. In order to extend the CM-5 system software to permit such applications, a multi-program loader was developed. This system is based on the dld loader which was originally developed for workstations. This paper provides a high level description of dld, and describes how it was ported to the CM-5 to provide support for multi-binary applications. Finally, it elaborates how the loader has been used to implement the CM-5 version of MPIRUN, a portable facility for running multi-disciplinary/multi-zonal MPI (Message-Passing Interface Standard) codes.
Blood, Ryan P; Rynell, Patrik W; Johnson, Peter W
2012-12-01
This study measured whole-body vibration (WBV) exposures in front-end loader operators, and evaluated the effects of traction chains and work tasks on their WBV exposures. WBV exposures were measured and compared across three different front-end loader tire configurations: (a) stock rubber tires, (b) rubber tires with ladder chains, and (c) rubber tires with basket chains. The operators completed three distinct standardized tasks: driving on a city street, simulated plowing, and a simulated scooping and dumping task. A portable data acquisition system collected tri-axial time weighted and raw WBV data per ISO 2631-1 and 2631-5 standards. In addition, Global Positioning System (GPS) data were collected in order to compare loader speeds across tire conditions and the standardized tasks. Relative to the stock rubber tires, both types of tire chains significantly increased WBV exposures with the ladder chains having substantially higher WBV exposures compared to basket chains. Additionally, there were task dependent differences in WBV exposures. During the driving task, the z-axis (up and down) was the predominant exposure; the plowing task had a more even distribution of exposure across all three axes; while during scooping and dumping task, the x-axis (fore and aft) had the highest WBV exposures. The GPS data indicated that there were significant speed differences across tasks but not between the basket and ladder chain conditions. Tires with ladder chains increased the front-end loader operators' exposure to WBV above the ISO 2631-1 recommended eight hour action limit increasing risk for adverse health effects. Although more expensive, basket chains are recommended over ladder chains since they substantially lowered the front-end loader operator's exposures and may ultimately reduce vibration related wear and tear on the vehicle. In order to reduce a heavy equipment vehicle (HEV) operator's chances for developing low back pain, this study provides information that health and safety professionals can use to reduce whole-body vibration (WBV) exposures when operating front-end wheel loaders with traction chains. Copyright © 2012 National Safety Council and Elsevier Ltd. All rights reserved.
Sound absorption by clamped poroelastic plates.
Aygun, H; Attenborough, K
2008-09-01
Measurements and predictions have been made of the absorption coefficient and the surface acoustic impedance of poroelastic plates clamped in a large impedance tube and separated from the rigid termination by an air gap. The measured and predicted absorption coefficient and surface impedance spectra exhibit low frequency peaks. The peak frequencies observed in the absorption coefficient are close to those predicted and measured in the deflection spectra of the clamped poroelastic plates. The influences of the rigidity of the clamping conditions and the width of the air gap have been investigated. Both influences are found to be important. Increasing the rigidity of clamping reduces the low frequency absorption peaks compared with those measured for simply supported plates or plates in an intermediate clamping condition. Results for a closed cell foam plate and for two open cell foam plates made from recycled materials are presented. For identical clamping conditions and width of air gap, the results for the different materials differ as a consequence mainly of their different elasticity, thickness, and cell structure.
2015-08-01
10 minutes. After this, the furnace was opened and the clamps were tightened to 6 in-lb of torque . At the end of the tests, we examined the specimens...to use a different procedure for tightening the clamps in the frequency sweep tests -- this is explained in the next section...procedure to tighten the clamps. This is described next. First, the test applies different frequencies at a large range of temperatures – from -110 C to 70
Drum ring removal/installation tool
Andrade, William Andrew [Livermore, CA
2006-11-14
A handheld tool, or a pair of such tools, such as for use in removing/installing a bolt-type clamping ring on a container barrel/drum, where the clamping ring has a pair of clamping ends each with a throughbore. Each tool has an elongated handle and an elongated lever arm transversely connected to one end of the handle. The lever arm is capable of being inserted into the throughbore of a selected clamping end and leveraged with the handle to exert a first moment on the selected clamping end. Each tool also has a second lever arm, such as a socket with an open-ended slot, which is suspended alongside the first lever arm. The second lever arm is capable of engaging the selected clamping end and being leveraged with the handle to exert a second moment which is orthogonal to the first moment. In this manner, the first and second moments operate to hold the selected clamping end fixed relative to the tool so that the selected clamping end may be controlled with the handle. The pair of clamping ends may also be simultaneously and independently controlled with the use of two handles/tools so as to contort the geometry of the drum clamping ring and enable its removal/installation.
John F. Kennedy Space Center's Wireless Hang Angle Instrumentation System
NASA Technical Reports Server (NTRS)
Kohler, Jeff
2009-01-01
The technology is a high-precision, wireless inclinometer. The system was designed for monitoring the suspension angle of the Orbiter vehicle during loading onto the Solid Rocket Boosters of the Space Shuttle. Originally, operators manually measured the alignment of the Orbiter with a hand-held inclinometer on a nonrigid surface. The measurement was open to interpretation by the loader. If the Orbiter is misaligned, it can crush ball joints and delay the loading while repairs are made. With this system, the Orbiter can be loaded without damage and without manual measurement.
Randomized clinical trial of stapler versus clamp-crushing transection in elective liver resection.
Rahbari, N N; Elbers, H; Koch, M; Vogler, P; Striebel, F; Bruckner, T; Mehrabi, A; Schemmer, P; Büchler, M W; Weitz, J
2014-02-01
Various devices have been developed to facilitate liver transection and reduce blood loss in liver resections. None of these has proven superiority compared with the classical clamp-crushing technique. This randomized clinical trial compared the effectiveness and safety of stapler transection with that of clamp-crushing during open liver resection. Patients admitted for elective open liver resection between January 2010 and October 2011 were assigned randomly to stapler transection or the clamp-crushing technique. The primary endpoint was the total amount of intraoperative blood loss. Secondary endpoints included transection time, duration of operation, complication rates and resection margins. A total of 130 patients were enrolled, 65 to clamp-crushing and 65 to stapler transection. There was no difference between groups in total intraoperative blood loss: median (i.q.r.) 1050 (525-1650) versus 925 (450-1425) ml respectively (P = 0·279). The difference in total intraoperative blood loss normalized to the transection surface area was not statistically significant (P = 0·092). Blood loss during parenchymal transection was significantly lower in the stapler transection group (P = 0·002), as were the parenchymal transection time (mean(s.d.) 30(21) versus 9(7) min for clamp-crushing and stapler transection groups respectively; P < 0·001) and total duration of operation (mean(s.d.) 221(86) versus 190(85) min; P = 0·047). There were no significant differences in postoperative morbidity (P = 0·863) or mortality (P = 0·684) between groups. Stapler transection is a safe technique but does not reduce intraoperative blood loss in elective liver resection compared with the clamp-crushing technique. NCT01049607 (http://www.clinicaltrials.gov). © 2014 BJS Society Ltd. Published by John Wiley & Sons Ltd.
Code of Federal Regulations, 2010 CFR
2010-07-01
... come within the exemption as a partial-duty loader. (Levinson v. Spector Motor Service, 330 U.S. 649... limited handling of them, that his activities will not come within the kind of “loading” which directly... it is light in weight, probably could not be loaded in a manner which would adversely affect “safety...
Code of Federal Regulations, 2011 CFR
2011-07-01
... come within the exemption as a partial-duty loader. (Levinson v. Spector Motor Service, 330 U.S. 649... limited handling of them, that his activities will not come within the kind of “loading” which directly... it is light in weight, probably could not be loaded in a manner which would adversely affect “safety...
25. FRONT END LOADERS MOMENTARILY IN REPOSE IN THE ORE ...
25. FRONT END LOADERS MOMENTARILY IN REPOSE IN THE ORE STORAGE YARD. AN ORE BRIDGE THAT FORMERLY TRANSFERRED ORE WITHIN THE STORAGE YARD WAS DESTROYED BY A BLIZZARD IN 1978. - Pennsylvania Railway Ore Dock, Lake Erie at Whiskey Island, approximately 1.5 miles west of Public Square, Cleveland, Cuyahoga County, OH
Safer methods of hauling coalface power loaders
DOE Office of Scientific and Technical Information (OSTI.GOV)
Whitworth, K.
1976-01-01
That power loader chains are a menace is evidenced by the Report of H. M. Chief Inspector of Mines and Quarries in Great Britain. In 1974, power loader haulage chains were responsible for 40 percent of all machinery accidents, with one person killed and 18 seriously injured compared with 23 seriously injured in 1973. Half the accidents occurred in the vicinity of the power loader sprockets when persons were struck by the end of a broken chain or were trapped between the chain and the sprocket. The present static haulage chain in tension along the whole length of face ismore » a continuing hazard and the most significant safety contribution that can be made is to design alternative means of haulage to eliminate the chain. Alternative means of haulage have or are being developed and equipment from six machinery manufacturers, from CERCHAR, the French research and development organization, and from the British National Coal Board were demonstrated at the National Coal Board's Swadlincote Test Site. A brief description of each item of equipment is given.« less
Measurement of Spindle Rigidity by using a Magnet Loader
NASA Astrophysics Data System (ADS)
Yamazaki, Taku; Matsubara, Atsushi; Fujita, Tomoya; Muraki, Toshiyuki; Asano, Kohei; Kawashima, Kazuyuki
The static rigidity of a rotating spindle in the radial direction is investigated in this research. A magnetic loading device (magnet loader) has been developed for the measurement. The magnet loader, which has coils and iron cores, generates the electromagnetic force and attracts a dummy tool attached to the spindle. However, the eddy current is generated in the dummy tool with the spindle rotation and reduces the attractive force at high spindle speed. In order to understand the magnetic flux and eddy current in the dummy tool, the electromagnetic field analysis by FEM was carried out. Grooves on the attraction surface of the dummy tool were designed to cut the eddy current flow. The dimension of the groove were decided based on the FEM analysis, and the designed tool were manufactured and tested. The test result shows that the designed tool successfully reduces the eddy current and recovers the attractive force. By using the magnet loader and the grooved tool, the spindle rigidity can be measured when the spindle rotates with a speed up to 10,000 min-1.
Sabbagh, Robert; Chawla, Arun; Tisdale, Britton; Kwan, Kevin; Chatterjee, Suman; Kwiecien, Jacek M.; Kapoor, Anil
2011-01-01
Background Thirty minutes has been considered as the threshold for tolerable warm ischemic time (WIT). Recent reports demonstrate recovery of renal function after longer WIT. We assessed renal histology according to different WIT in a 2-kidney porcine model. Methods Twelve female pigs were randomized to an open or laparoscopic group. Each pig was further randomized within each group to clamping the left renal artery for 5, 15, 30, 45, 60 or 180 minutes. Preclamping left renal biopsies were performed on each pig. The contralateral kidney in each animal was used as an individual control. On postoperative day 14, all animals underwent bilateral nephrectomies. Preclamping left renal biopsies and all renal specimens were evaluated by a blinded veterinary pathologist. Results One pig died in the open group after 180 minutes of clamping. Histopathology did not show any significant changes between the two groups and across clamp times from 5 to 60 minutes. After 180 minutes of laparoscopic clamping, there was evidence of diffuse necrosis. Interpretation Sixty minutes of ischemia did not show any permanent renal damage in both groups. Further studies are needed to verify these findings in humans. A prolonged ischemic time without permanent renal damage would be helpful in partial nephrectomy. Warm ischemic time of 180 minutes exceeded the renal ischemic burden based on histological features. PMID:21470513
Dregelid, Einar Børre; Lilleng, Peer Kåre
2016-01-01
When ischemic events ascribable to microembolization occur during open repair of proximal abdominal aortic aneurysms, a likely origin of atheroembolism is not always found. A 78-year old man with enlargement of the entire aorta underwent open repair for a pararenal abdominal aortic aneurysm using supraceliac aortic clamping for 20min. Then the graft was clamped, the supraceliac clamp was removed, and the distal and right renal anastomoses were also completed. The patient was stable throughout the operation with only transient drop in blood pressure on reperfusion. Postoperatively the patient developed ischemia, attributable to microembolization, in legs, small intestine, gall bladder and kidneys. He underwent fasciotomy, small bowel and gall bladder resections. Intestinal absorptive function did not recover adequately and he died after 4 months. Microscopic examination of hundreds of intestinal, juxtaintestinal mesenteric, and gall bladder arteries showed a few ones containing cholesterol emboli. It is unsure whether a few occluded small arteries out of several hundred could have caused the ischemic injury alone. There had been only moderate backbleeding from aortic branches above the proximal anastomosis while it was sutured. Inadvertently, remaining air in the graft, aorta, and aortic branches may have been whipped into the pulsating blood, resulting in air microbubbles, when the aortic clamp was removed. Although both atheromatous particles and air microbubbles are well-known causes of iatrogenic microembolization, the importance of air microembolization in open repair of pararenal aortic aneurysms is not known and need to be studied. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Lewis, Jacob S.; Spenkelink, Lisanne M.; Schauer, Grant D.; Hill, Flynn R.; Georgescu, Roxanna E.; O’Donnell, Michael E.; van Oijen, Antoine M.
2017-01-01
The replisome, the multiprotein system responsible for genome duplication, is a highly dynamic complex displaying a large number of different enzyme activities. Recently, the Saccharomyces cerevisiae minimal replication reaction has been successfully reconstituted in vitro. This provided an opportunity to uncover the enzymatic activities of many of the components in a eukaryotic system. Their dynamic behavior and interactions in the context of the replisome, however, remain unclear. We use a tethered-bead assay to provide real-time visualization of leading-strand synthesis by the S. cerevisiae replisome at the single-molecule level. The minimal reconstituted leading-strand replisome requires 24 proteins, forming the CMG helicase, the Pol ε DNA polymerase, the RFC clamp loader, the PCNA sliding clamp, and the RPA single-stranded DNA binding protein. We observe rates and product lengths similar to those obtained from ensemble biochemical experiments. At the single-molecule level, we probe the behavior of two components of the replication progression complex and characterize their interaction with active leading-strand replisomes. The Minichromosome maintenance protein 10 (Mcm10), an important player in CMG activation, increases the number of productive replication events in our assay. Furthermore, we show that the fork protection complex Mrc1–Tof1–Csm3 (MTC) enhances the rate of the leading-strand replisome threefold. The introduction of periods of fast replication by MTC leads to an average rate enhancement of a factor of 2, similar to observations in cellular studies. We observe that the MTC complex acts in a dynamic fashion with the moving replisome, leading to alternating phases of slow and fast replication. PMID:28923950
Comparison of mechanized systems for thinning Ponderosa pine and mixed conifer stands
Bruce R. Hartsough; Joseph F. McNeel; Thomas A. Durston; Bryce J. Stokes
1994-01-01
We studied three systems for thinning pine plantations and naturally-regenerated stands on the Stanislaus National Forest, California. All three produced small sawlogs and fuel chips. The whole tree system consisted of a feller buncher, skidder, stroke processor, loader and chipper. The cut-to-length system included a harvester, forwarder, loader and chipper. A hybrid...
Comparison of mechanized systems for thinning Ponderosa pine and mixed conifer stands
Bruce R. Hartsough; Joseph F. McNeel; Thomas A. Durston; Bryce J. Stokes
1994-01-01
Three systems for thinning pine plantations and naturally-regenerated stands were studied. All three produced small sawlogs and fuel chips. The whole-tree system consisted of a feller buncher, skidder, stroke processor, loader, and chipper. The cut-to-length system included a harvester, forwarder, loader, and chipper. A hybrid system combined a feller buncher,...
NASA Technical Reports Server (NTRS)
Robbins, John S.
1988-01-01
Unit removed with minimal disturbance. Valve inlet and outlet ports adjacent to each other on same side of valve body. Ports inserted into special manifold on fluid line. Valve body attached to manifold by four bolts or, alternatively, by toggle clamps. Electromechanical actuator moves in direction parallel to fluid line to open and close valve. When necessary to clean valve, removed simply by opening bolts or toggle clamps. No need to move or separate ports of fluid line. Valve useful where disturbance of fluid line detrimental or where fast maintenance essential - in oil and chemical industries, automotive vehicles, aircraft, and powerplants.
Correlation of open cell-attached and excised patch clamp techniques.
Filipovic, D; Hayslett, J P
1995-11-01
The excised patch clamp configuration provides a unique technique for some types of single channel analyses, but maintenance of stable, long-lasting preparations may be confounded by rundown and/or rapid loss of seal. Studies were performed on the amiloride-sensitive Na+ channel, located on the apical surface of A6 cells, to determine whether the nystatin-induced open cell-attached patch could serve as an alternative configuration. Compared to excised inside-out patches, stable preparations were achieved more readily with the open cell-attached patch (9% vs. 56% of attempts). In both preparations, the current voltage (I-V) relation was linear, current amplitudes were equal at opposite equivalent clamped voltages, and Erev was zero in symmetrical Na+ solutions, indicating similar Na+ activities on the cytosolic and external surfaces of the patch. Moreover, there was no evidence that nystatin altered channel activity in the patch because slope conductance (3-4pS) and Erev (75 mV), when the bath was perfused with a high K:low Na solution (ENa = 80 mV), were nearly equal in both patch configurations. Our results therefore indicate that the nystatin-induced open cell-attached patch can serve as an alternative approach to the excised inside-out patch when experiments require modulation of univalent ions in the cytosol.
Muller, Onno; Cohu, Christopher M; Stewart, Jared J; Protheroe, Johanna A; Demmig-Adams, Barbara; Adams, William W
2014-09-01
Foliar vascular anatomy and photosynthesis were evaluated for a number of summer annual species that either load sugars into the phloem via a symplastic route (Cucumis sativus L. cv. Straight Eight; Cucurbita pepo L. cv. Italian Zucchini Romanesco; Citrullus lanatus L. cv. Faerie Hybrid; Cucurbita pepo L. cv. Autumn Gold) or an apoplastic route (Nicotiana tabacum L.; Solanum lycopersicum L. cv. Brandywine; Gossypium hirsutum L.; Helianthus annuus L. cv. Soraya), as well as winter annual apoplastic loaders (Spinacia oleracea L. cv. Giant Nobel; Arabidopsis thaliana (L.) Heynhold Col-0, Swedish and Italian ecotypes). For all summer annuals, minor vein cross-sectional xylem area and tracheid number as well as the ratio of phloem loading cells to phloem sieve elements, each when normalized for foliar vein density (VD), was correlated with photosynthesis. These links presumably reflect (1) the xylem's role in providing water to meet foliar transpirational demand supporting photosynthesis and (2) the importance of the driving force of phloem loading as well as the cross-sectional area for phloem sap flux to match foliar photosynthate production. While photosynthesis correlated with the product of VD and cross-sectional phloem cell area among symplastic loaders, photosynthesis correlated with the product of VD and phloem cell number per vein among summer annual apoplastic loaders. Phloem cell size has thus apparently been a target of selection among symplastic loaders (where loading depends on enzyme concentration within loading cells) versus phloem cell number among apoplastic loaders (where loading depends on membrane transporter numbers). © 2014 Scandinavian Plant Physiology Society.
Training Effectiveness Study of Simulator Usage and Its Impact on Live Fire Armor Gunnery
2014-06-01
including artillery Round loading and reloading sounds Loader’s “UP” Main gun , M240, and M2 machine gun firing Track clatter Engine and...functional TC’s hatch will not open M2 machine gun is not replicated on the AGTS Not all circuit breakers are supported from the display panels 18...Driver’s and loader’s stations are not simulated Of the limitations listed above, three are of most concern: the lack of M2 machine gun
Production and Costs of the Chambers Delimbinator in First Thinning of Pine Plantations
Scott T. Mooney; Kevin D. Boston; W. Dale Greene
2000-01-01
Production and quality measures were collected and analyzed for a new chain-flail delimbing machine, Chambers Delimbinator, on two operations in central and southwestern Georgia. The first operation, Logger A, used two skidders and one loader while the second operation, Logger B, used two skidder and two loaders. Lobber B with the lower cycle time and larger piece...
ERIC Educational Resources Information Center
Poli, Bonnie; Fluker, Sam S.
Written in English and Spanish and completely illustrated, this manual provides basic safety information for pesticide workers. Mixers, loaders, and applicators work with pesticides at their greatest strength and have the highest risk of poisoning. Understanding the pesticide label is the first step to pesticide safety. The words…
Cutter-loader apparatus having overhung shearer drum
DOE Office of Scientific and Technical Information (OSTI.GOV)
Groger, H.; Harms, E.E.
1984-05-01
A longwall mining machine includes a drum cutter-loader and face conveyor wherein the drum cutter-loader is overhung and is supported by a support arm adjacent to the mine face. Nozzles direct high pressure liquid jets against the forward edge of the support arm to cut away the mining face and permit the face side support arm to advance as the mining machine advances. In one embodiment the nozzles are provided along an inclined cutting edge at the forward end of the support arm. Such nozzles may be fixed or oscillating. In an alternative embodiment the nozzles are provided in themore » cylindrical edge zone of the shearer drum and direct the high pressure fluid jets against the cutter edge at the forward end of the support arm.« less
Flange joint system for SRF cavities utilizing high force spring clamps for low particle generation
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
A flange joint system for SRF cavities. The flange joint system includes a set of high force spring clamps that produce high force on the simple flanges of Superconducting Radio Frequency (SRF) cavities to squeeze conventional metallic seals. The system establishes the required vacuum and RF-tight seal with minimum particle contamination to the inside of the cavity assembly. The spring clamps are designed to stay within their elastic range while being forced open enough to mount over the flange pair. Upon release, the clamps have enough force to plastically deform metallic seal surfaces and continue to a new equilibrium sprungmore » dimension where the flanges remain held against one another with enough preload such that normal handling will not break the seal.« less
Surendranath, V; Albrecht, V; Hayhurst, J D; Schöne, B; Robinson, J; Marsh, S G E; Schmidt, A H; Lange, V
2017-07-01
Recent years have seen a rapid increase in the discovery of novel allelic variants of the human leukocyte antigen (HLA) genes. Commonly, only the exons encoding the peptide binding domains of novel HLA alleles are submitted. As a result, the IPD-IMGT/HLA Database lacks sequence information outside those regions for the majority of known alleles. This has implications for the application of the new sequencing technologies, which deliver sequence data often covering the complete gene. As these technologies simplify the characterization of the complete gene regions, it is desirable for novel alleles to be submitted as full-length sequences to the database. However, the manual annotation of full-length alleles and the generation of specific formats required by the sequence repositories is prone to error and time consuming. We have developed TypeLoader to address both these facets. With only the full-length sequence as a starting point, Typeloader performs automatic sequence annotation and subsequently handles all steps involved in preparing the specific formats for submission with very little manual intervention. TypeLoader is routinely used at the DKMS Life Science Lab and has aided in the successful submission of more than 900 novel HLA alleles as full-length sequences to the European Nucleotide Archive repository and the IPD-IMGT/HLA Database with a 95% reduction in the time spent on annotation and submission when compared with handling these processes manually. TypeLoader is implemented as a web application and can be easily installed and used on a standalone Linux desktop system or within a Linux client/server architecture. TypeLoader is downloadable from http://www.github.com/DKMS-LSL/typeloader. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Tripal v1.1: a standards-based toolkit for construction of online genetic and genomic databases.
Sanderson, Lacey-Anne; Ficklin, Stephen P; Cheng, Chun-Huai; Jung, Sook; Feltus, Frank A; Bett, Kirstin E; Main, Dorrie
2013-01-01
Tripal is an open-source freely available toolkit for construction of online genomic and genetic databases. It aims to facilitate development of community-driven biological websites by integrating the GMOD Chado database schema with Drupal, a popular website creation and content management software. Tripal provides a suite of tools for interaction with a Chado database and display of content therein. The tools are designed to be generic to support the various ways in which data may be stored in Chado. Previous releases of Tripal have supported organisms, genomic libraries, biological stocks, stock collections and genomic features, their alignments and annotations. Also, Tripal and its extension modules provided loaders for commonly used file formats such as FASTA, GFF, OBO, GAF, BLAST XML, KEGG heir files and InterProScan XML. Default generic templates were provided for common views of biological data, which could be customized using an open Application Programming Interface to change the way data are displayed. Here, we report additional tools and functionality that are part of release v1.1 of Tripal. These include (i) a new bulk loader that allows a site curator to import data stored in a custom tab delimited format; (ii) full support of every Chado table for Drupal Views (a powerful tool allowing site developers to construct novel displays and search pages); (iii) new modules including 'Feature Map', 'Genetic', 'Publication', 'Project', 'Contact' and the 'Natural Diversity' modules. Tutorials, mailing lists, download and set-up instructions, extension modules and other documentation can be found at the Tripal website located at http://tripal.info. DATABASE URL: http://tripal.info/.
Tripal v1.1: a standards-based toolkit for construction of online genetic and genomic databases
Sanderson, Lacey-Anne; Ficklin, Stephen P.; Cheng, Chun-Huai; Jung, Sook; Feltus, Frank A.; Bett, Kirstin E.; Main, Dorrie
2013-01-01
Tripal is an open-source freely available toolkit for construction of online genomic and genetic databases. It aims to facilitate development of community-driven biological websites by integrating the GMOD Chado database schema with Drupal, a popular website creation and content management software. Tripal provides a suite of tools for interaction with a Chado database and display of content therein. The tools are designed to be generic to support the various ways in which data may be stored in Chado. Previous releases of Tripal have supported organisms, genomic libraries, biological stocks, stock collections and genomic features, their alignments and annotations. Also, Tripal and its extension modules provided loaders for commonly used file formats such as FASTA, GFF, OBO, GAF, BLAST XML, KEGG heir files and InterProScan XML. Default generic templates were provided for common views of biological data, which could be customized using an open Application Programming Interface to change the way data are displayed. Here, we report additional tools and functionality that are part of release v1.1 of Tripal. These include (i) a new bulk loader that allows a site curator to import data stored in a custom tab delimited format; (ii) full support of every Chado table for Drupal Views (a powerful tool allowing site developers to construct novel displays and search pages); (iii) new modules including ‘Feature Map’, ‘Genetic’, ‘Publication’, ‘Project’, ‘Contact’ and the ‘Natural Diversity’ modules. Tutorials, mailing lists, download and set-up instructions, extension modules and other documentation can be found at the Tripal website located at http://tripal.info. Database URL: http://tripal.info/ PMID:24163125
DOE Office of Scientific and Technical Information (OSTI.GOV)
Strassner, II, Bernd H.; Liedtke, Richard; McDonald, Jacob Jeremiah
The various technologies presented herein relate to utilizing a sealing layer of malleable material to seal gaps, etc., at a joint between edges of a waveguide channel formed in a first plate and a surface of a clamping plate. A compression pad is included in the surface of the clamping plate and is dimensioned such that the upper surface of the pad is less than the area of the waveguide channel opening on the first plate. The sealing layer is placed between the waveguide plate and the clamping plate, and during assembly of the waveguide module, the compression pad deformsmore » a portion of the sealing layer such that it ingresses into the waveguide channel opening. Deformation of the sealing layer results in the gaps, etc., to be filled, improving the operational integrity of the joint.« less
Actuator development for the Instrument Pointing System (IPS)
NASA Technical Reports Server (NTRS)
Suttner, K.
1984-01-01
The mechanisms of the instrument pointing system (IPS) are described. Particular emphasis is placed on the actuators which are necessary for operating the IPS. The actuators are described as follows: (1) two linear actuators that clamp the gimbals down during ascent and descent; (2) two linear actuators that attach the payload to the IPS during the mission, and release it into the payload clamps; (3) one rotational actuator that opens and closes the payload clamps; and (4) three identical drive units that represent the three orthogonal gimbal axes and are the prime movers for pointing. Design features, manufacturing problems, test performance, and results are presented.
1982-04-01
the gas particulate filter system MODULE L: OPERATE THE M250 BRENADE LAUNCHER 1L. Load the grenade launcher 2L. Unload the grenade launcher MODULE M...k Initia~ng Stimulus: Thei (11rdLr from the T.C. to load the M250 .p grenade launcher. J ACTION Loader will: 1L. Load the grenade launcher. 2L. Unload
Ross, John H; Hewitt, Andrew; Armitage, James; Solomon, Keith; Watkins, Deborah K; Ginevan, Michael E
2015-02-01
Using validated models and methods routinely employed by pesticide regulatory agencies, the absorbed dosages of Agent Orange (AO) herbicide contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were estimated for mixer/loaders, applicators, and individuals in the vicinity of applications of AO by C-123 aircraft during the Vietnam War. Resulting dosages of TCDD were then transformed to estimates of adipose residues, and compared to population biomonitoring of known mixer/loaders and applicators as well as ground troops in Vietnam and civilians in the U.S. Results demonstrate that mixer/loaders and applicators had the greatest exposures and their measured residues of TCDD in adipose were consistent with the estimated exposures. Further, the potentially exposed ground troops, including those who could have been directly sprayed during aerial defoliation, had measured adipose residues that were consistent with those in civilian U.S. populations with no defined source of exposure exposures and both of those cohorts had orders of magnitude less exposure than the mixer/loaders or applicators. Despite the availability of validated exposure modeling methods for decades, the quantitative TCDD dose estimates presented here are the first of their kind for the Vietnam conflict. Copyright © 2014 Elsevier B.V. All rights reserved.
The effects of a dynamic graphical model during simulation-based training of console operation skill
NASA Technical Reports Server (NTRS)
Farquhar, John D.; Regian, J. Wesley
1993-01-01
LOADER is a Windows-based simulation of a complex procedural task. The task requires subjects to execute long sequences of console-operation actions (e.g., button presses, switch actuations, dial rotations) to accomplish specific goals. The LOADER interface is a graphical computer-simulated console which controls railroad cars, tracks, and cranes in a fictitious railroad yard. We hypothesized that acquisition of LOADER performance skill would be supported by the representation of a dynamic graphical model linking console actions to goal and goal states in the 'railroad yard'. Twenty-nine subjects were randomly assigned to one of two treatments (i.e., dynamic model or no model). During training, both groups received identical text-based instruction in an instructional-window above the LOADER interface. One group, however, additionally saw a dynamic version of the bird's-eye view of the railroad yard. After training, both groups were tested under identical conditions. They were asked to perform the complete procedure without guidance and without access to either type of railroad yard representation. Results indicate that rather than becoming dependent on the animated rail yard model, subjects in the dynamic model condition apparently internalized the model, as evidenced by their performance after the model was removed.
AstroML: "better, faster, cheaper" towards state-of-the-art data mining and machine learning
NASA Astrophysics Data System (ADS)
Ivezic, Zeljko; Connolly, Andrew J.; Vanderplas, Jacob
2015-01-01
We present AstroML, a Python module for machine learning and data mining built on numpy, scipy, scikit-learn, matplotlib, and astropy, and distributed under an open license. AstroML contains a growing library of statistical and machine learning routines for analyzing astronomical data in Python, loaders for several open astronomical datasets (such as SDSS and other recent major surveys), and a large suite of examples of analyzing and visualizing astronomical datasets. AstroML is especially suitable for introducing undergraduate students to numerical research projects and for graduate students to rapidly undertake cutting-edge research. The long-term goal of astroML is to provide a community repository for fast Python implementations of common tools and routines used for statistical data analysis in astronomy and astrophysics (see http://www.astroml.org).
Micromachined patch-clamp apparatus
Okandan, Murat
2012-12-04
A micromachined patch-clamp apparatus is disclosed for holding one or more cells and providing electrical, chemical, or mechanical stimulation to the cells during analysis with the patch-clamp technique for studying ion channels in cell membranes. The apparatus formed on a silicon substrate utilizes a lower chamber formed from silicon nitride using surface micromachining and an upper chamber formed from a molded polymer material. An opening in a common wall between the chambers is used to trap and hold a cell for analysis using the patch-clamp technique with sensing electrodes on each side of the cell. Some embodiments of the present invention utilize one or more electrostatic actuators formed on the substrate to provide mechanical stimulation to the cell being analyzed, or to provide information about mechanical movement of the cell in response to electrical or chemical stimulation.
The Human Operator and System Effectiveness.
1984-06-01
required in some decision process (e. g., component selection). 14 le NWC TP 6541 3. Be clearly stated in the final study report, with the rationale...BICYC LES t 5 - : BUSRSTO %* -.-’. ... % .% % . . J . % ... ~ ,4~ V’ .- *’ .-.-. , -LOADER T 1 = 1 + t 2 + LARGEST OF (t 3, t 4, t5) ,’ .t 2 t 3...34’,"t OPEN I UNLOAD " "I t DOORS PASSENGERSHI H" "" I PARK" "B. I AT t 5 t 4 BU SO OPERATE UNLOAD • . _ P LO A D ER BICYC LES -’, ",T 1 t I + L A R G
GFU-6/E 30mm Ammunition Loader for GAU-8A Gun System
1975-12-01
dropped onto the conveyor (See Figure 17) and transferred to the aircraft on these elements through flexible chuting which interfaces directly with the...14. Dwell Linkage 19 15. Horizontal Conveyor - Flex Chute Interface 20 16. Element Turnaround Sprocket 21 17. Horizontal Conveyor 22 18. Load Head... conveyor element mechanism for transport to the GAU-8/A loader unit. d. The contractor shall design the automated loading system to accept unfired
Modernization of Deployable Airfield Debris Removal Equipment
2017-04-01
cleared the debris away from the crater by lowering the front bucket and setting the bottom blade at a 45-deg angle. The debris was pushed...the Komatsu WA 150 baseline loader. The crater clearing process involved the loader orienting the bucket blade at approximately 45 deg to the...wider than the track’s width (Figure 30). This caused debris to run under the track and lift the equipment, potentially throwing the operator. The final
The National Shipbuilding Research Program: Solid Waste Segregation and Recycling
1998-03-01
Shields , Recycling Coordinator D.C. Department of Public Works 65 K Street, NE Washington, DC 20002 202-727-5887 Task Three, Tab Three Page 42 George...SHEAR X FRONT END LOADERS = CONVEYORS X FORKLIFTS O WEIGHT SCALES X PROCESSING DROP-BALL BREAKAGE X CUTTING TORCHES GAS = PLASMA = POWDER = WATER-JET...Loaders Conveyors Forklifts Weight Scales Processing Drop-ball Breakage Cutting Torches Gas Plasma Powder Laser Water-jet Abrasive disk Shears Ferrous
Dynamic Clamp in Cardiac and Neuronal Systems Using RTXI
Ortega, Francis A.; Butera, Robert J.; Christini, David J.; White, John A.; Dorval, Alan D.
2016-01-01
The injection of computer-simulated conductances through the dynamic clamp technique has allowed researchers to probe the intercellular and intracellular dynamics of cardiac and neuronal systems with great precision. By coupling computational models to biological systems, dynamic clamp has become a proven tool in electrophysiology with many applications, such as generating hybrid networks in neurons or simulating channelopathies in cardiomyocytes. While its applications are broad, the approach is straightforward: synthesizing traditional patch clamp, computational modeling, and closed-loop feedback control to simulate a cellular conductance. Here, we present two example applications: artificial blocking of the inward rectifier potassium current in a cardiomyocyte and coupling of a biological neuron to a virtual neuron through a virtual synapse. The design and implementation of the necessary software to administer these dynamic clamp experiments can be difficult. In this chapter, we provide an overview of designing and implementing a dynamic clamp experiment using the Real-Time eXperiment Interface (RTXI), an open- source software system tailored for real-time biological experiments. We present two ways to achieve this using RTXI’s modular format, through the creation of a custom user-made module and through existing modules found in RTXI’s online library. PMID:25023319
Improved memory loading techniques for the TSRV display system
NASA Technical Reports Server (NTRS)
Easley, W. C.; Lynn, W. A.; Mcluer, D. G.
1986-01-01
A recent upgrade of the TSRV research flight system at NASA Langley Research Center retained the original monochrome display system. However, the display memory loading equipment was replaced requiring design and development of new methods of performing this task. This paper describes the new techniques developed to load memory in the display system. An outdated paper tape method for loading the BOOTSTRAP control program was replaced by EPROM storage of the characters contained on the tape. Rather than move a tape past an optical reader, a counter was implemented which steps sequentially through EPROM addresses and presents the same data to the loader circuitry. A cumbersome cassette tape method for loading the applications software was replaced with a floppy disk method using a microprocessor terminal installed as part of the upgrade. The cassette memory image was transferred to disk and a specific software loader was written for the terminal which duplicates the function of the cassette loader.
Improvement of loading and transport bodies of tunneling machines
NASA Astrophysics Data System (ADS)
Nosenko, A. S.; Isakov, V. S.; Domnitskiy, A. A.; Shemshura, E. A.; Zubov, V. V.
2017-10-01
The article discusses the use of sets of equipment for mining and construction of road tunnels with the use of a self-propelled vehicle and bunker loaders to transport the mined rock. A patented design of the tunneling combine loading body, which allows adjusting its performance and power consumption in the loading mode, is considered. Reducing stress in extreme situations will make it possible to avoid overloading the drive and increase the reliability of the combine as a whole. The scheme of one of the most promising variants of the wedge bunker loader with variable geometry of the conveying elements is presented. The proposed design solves the problem of “locking” the material in narrow parts of the conveying body or in places where loading and transport bodies of different width are connected, as well as in the blast-and-heap mode of the loader.
Wrapping SRS with CORBA: from textual data to distributed objects.
Coupaye, T
1999-04-01
Biological data come in very different shapes. Databanks are maintained and used by distinct organizations. Text is the de facto Standard exchange format. The SRS system can integrate heterogeneous textual databanks but it was lacking a way to structure the extracted data. This paper presents a CORBA interface to the SRS system which manages databanks in a flat file format. SRS Object Servers are CORBA wrappers for SRS. They allow client applications (visualisation tools, data mining tools, etc.) to access and query SRS servers remotely through an Object Request Broker (ORB). They provide loader objects that contain the information extracted from the databanks by SRS. Loader objects are not hard-coded but generated in a flexible way by using loader specifications which allow SRS administrators to package data coming from distinct databanks. The prototype may be available for beta-testing. Please contact the SRS group (http://srs.ebi.ac.uk).
ERIC Educational Resources Information Center
San Mateo County Office of Education, Redwood City, CA. Career Preparation Centers.
This fifteenth of fifteen sets of Adult Competency Education (ACE) Competency Based Job Descriptions in the ACE kit contains job descriptions for Bus Driver, General Loader, Forklift Operator, and Material Handler. Each begins with a fact sheet that includes this information: occupational title, D.O.T. code, ACE number, career ladder, D.O.T.…
Elan4/SPARC V9 Cross Loader and Dynamic Linker
DOE Office of Scientific and Technical Information (OSTI.GOV)
anf Fabien Lebaillif-Delamare, Fabrizio Petrini
2004-10-25
The Elan4/Sparc V9 Croos Loader and Liner is a part of the Linux system software that allows the dynamic loading and linking of user code in the network interface Quadrics QsNETII, also called as Elan4 Quadrics. Elan44 uses a thread processor that is based on the assembly instruction set of the Sparc V9. All this software is integrated as a Linux kernel module in the Linux 2.6.5 release.
Role of the pH in state-dependent blockade of hERG currents
NASA Astrophysics Data System (ADS)
Wang, Yibo; Guo, Jiqing; Perissinotti, Laura L.; Lees-Miller, James; Teng, Guoqi; Durdagi, Serdar; Duff, Henry J.; Noskov, Sergei Yu.
2016-10-01
Mutations that reduce inactivation of the voltage-gated Kv11.1 potassium channel (hERG) reduce binding for a number of blockers. State specific block of the inactivated state of hERG block may increase risks of drug-induced Torsade de pointes. In this study, molecular simulations of dofetilide binding to the previously developed and experimentally validated models of the hERG channel in open and open-inactivated states were combined with voltage-clamp experiments to unravel the mechanism(s) of state-dependent blockade. The computations of the free energy profiles associated with the drug block to its binding pocket in the intra-cavitary site display startling differences in the open and open-inactivated states of the channel. It was also found that drug ionization may play a crucial role in preferential targeting to the open-inactivated state of the pore domain. pH-dependent hERG blockade by dofetilie was studied with patch-clamp recordings. The results show that low pH increases the extent and speed of drug-induced block. Both experimental and computational findings indicate that binding to the open-inactivated state is of key importance to our understanding of the dofetilide’s mode of action.
Logic Design of a Shared Disk System in a Multi-Micro Computer Environment.
1983-06-01
overall system, is given. An exnaustive description of eacn device can De found in tne cited references. A. INTEL 80S5 Tne INTEL Be86 is a nign...eitner could De accomplished, it was necessary to understand ootn tne existing system arcnitecture ani software. Tne last cnapter addressed tnat...to De adapted: tne loader program and tne Doot ROP program. Tne loader program is a simplified version of CP/M-Bö and contains cniy encu^n file
Safety of minimally invasive mitral valve surgery without aortic cross-clamp.
Umakanthan, Ramanan; Leacche, Marzia; Petracek, Michael R; Kumar, Sathappan; Solenkova, Nataliya V; Kaiser, Clayton A; Greelish, James P; Balaguer, Jorge M; Ahmad, Rashid M; Ball, Stephen K; Hoff, Steven J; Absi, Tarek S; Kim, Betty S; Byrne, John G
2008-05-01
We developed a technique for open heart surgery through a small (5 cm) right-anterolateral thoracotomy without aortic cross-clamp. One hundred and ninety-five consecutive patients (103 male and 92 female), age 69 +/- 8 years, underwent surgery between January 2006 and July 2007. Mean preoperative New York Heart Association function class was 2.2 +/- 0.7. Thirty-five patients (18%) had an ejection fraction 0.35 or less. Cardiopulmonary bypass was instituted through femoral (176 of 195, 90%), axillary (18 of 195, 9%), or direct aortic (1 of 195, 0.5%) cannulation. Under cold fibrillatory arrest (mean temperature 28.2 degrees C) without aortic cross-clamp, mitral valve repair (72 of 195, 37%), mitral valve replacement (117 of 195, 60%), or other (6 of 195, 3%) procedures were performed. Concomitant procedures included maze (45 of 195, 23%), patent foramen ovale closure (42 of 195, 22%) and tricuspid valve repair (16 of 195, 8%), or replacement (4 of 195, 2%). Thirty-day mortality was 3% (6 of 195). Duration of fibrillatory arrest, cardiopulmonary bypass, and "skin to skin" surgery were 88 +/- 32, 118 +/- 52, and 280 +/- 78 minutes, respectively. Ten patients (5%) underwent reexploration for bleeding and 44% did not receive any blood transfusions. Six patients (3%) sustained a postoperative stroke, eight (4%) developed low cardiac output syndrome, and two (1%) developed renal failure requiring hemodialysis. Mean length of hospital stay was 7 +/- 4.8 days. This simplified technique of minimally invasive open heart surgery is safe and easily reproducible. Fibrillatory arrest without aortic cross-clamping, with coronary perfusion against an intact aortic valve, does not increase the risk of stroke or low cardiac output. It may be particularly useful in higher risk patients in whom sternotomy with aortic clamping is less desirable.
Chi, Feng; Zhou, Jun; Zhang, Qi; Wang, Yong; Huang, Panling
2017-01-01
The vibration control of a construction vehicle must be carried out in order to meet the aims of sustainable environmental development and to avoid the potential human health hazards. In this paper, based on market feedback, the driver seat vibration of a type of wheel loader in the left and right direction, is found to be significant over a certain speed range. In order to find abnormal vibration components, the order tracking technique (OTT) and transmission path analysis (TPA) were used to analyze the vibration sources of the wheel loader. Through this analysis, it can be seen that the abnormal vibration comes from the interaction between the tire tread and the road, and this is because the vibration was amplified by the cab mount, which was eventually transmitted to the cab seat. Finally, the seat vibration amplitudes were decreased by up to 50.8%, after implementing the vibration reduction strategy. PMID:28282849
Chi, Feng; Zhou, Jun; Zhang, Qi; Wang, Yong; Huang, Panling
2017-03-08
The vibration control of a construction vehicle must be carried out in order to meet the aims of sustainable environmental development and to avoid the potential human health hazards. In this paper, based on market feedback, the driver seat vibration of a type of wheel loader in the left and right direction, is found to be significant over a certain speed range. In order to find abnormal vibration components, the order tracking technique (OTT) and transmission path analysis (TPA) were used to analyze the vibration sources of the wheel loader. Through this analysis, it can be seen that the abnormal vibration comes from the interaction between the tire tread and the road, and this is because the vibration was amplified by the cab mount, which was eventually transmitted to the cab seat. Finally, the seat vibration amplitudes were decreased by up to 50.8%, after implementing the vibration reduction strategy.
A monolithic patch-clamping amplifier with capacitive feedback.
Prakash, J; Paulos, J J; Jensen, D N
1989-03-01
Patch-clamping is an established method for directly measuring ionic transport through cellular membranes with sufficient resolution to observe open/close transitions of individual channel molecules. This paper describes an alternative technique for patch-clamping which uses a capacitor as the transimpedance element. This approach eliminates bandwidth and saturation limitations experienced with resistive patch-clamping amplifiers. A complete monolithic design featuring an on-chip operational amplifier, a capacitor array with gain-ranging from 30 pF down to 0.03 pF, and reset and gain ranging switches has been fabricated using 5 microns CMOS technology. It is shown that the voltage noise of the CMOS operational amplifier limits the overall noise performance, but that performance competitive with conventional instruments can be achieved over a 10 kHz bandwidth, at least for small input capacitances (less than or equal to 5 pF). Results are presented along with an analysis and comparison of noise performance using both resistive and capacitive elements.
Apoplastic and symplastic phloem loading in Quercus robur and Fraxinus excelsior
Lohaus, Gertrud
2014-01-01
Whereas most of the research on phloem loading is performed on herbaceous plants, less is known about phloem loading strategies in trees. In this study, the phloem loading mechanisms of Quercus robur and Fraxinus excelsior were analysed. The following features were examined: the minor vein structure, the sugar concentrations in phloem sap by the laser–aphid–stylet technique, the distribution of photoassimilates in the mesophyll cells by non-aqueous fractionation, gradients of sugar concentrations and osmotic pressure, and the expression of sucrose transporters. The minor vein configurations of Q. robur and F. excelsior belong to the open type. Quercus robur contained companion cells in the minor veins whereas F. excelsior showed intermediary cells in addition to ordinary companion cells. The main carbon transport form in Q. robur was sucrose (~1M). In F. excelsior high amounts of raffinose and stachyose were also transported. However, in both tree species, the osmolality of phloem sap was higher than the osmolality of the mesophyll cells. The concentration gradients between phloem sap and the cytoplasm of mesophyll cells for sucrose were 16-fold and 14-fold for Q. robur and F. excelsior, respectively. Independent of the type of translocated sugars, sucrose transporter cDNAs were cloned from both species. The results indicate that phloem loading of sucrose and other metabolites must involve active loading steps in both tree species. Quercus robur seems to be an apoplastic phloem loader while F. excelsior shows indications of being a symplastic or mixed symplastic–apoplastic phloem loader. PMID:24591056
NASA Technical Reports Server (NTRS)
Ko, William L.
1999-01-01
Increasing use of curved sandwich panels as aerospace structure components makes it vital to fully understand their thermostructural behavior and identify key factors affecting the open-mode debonding failure. Open-mode debonding analysis is performed on a family of curved honeycomb-core sandwich panels with different radii of curvature. The curved sandwich panels are either simply supported or clamped, and are subjected to uniform heating on the convex side and uniform cryogenic cooling on the concave side. The finite-element method was used to study the effects of panel curvature and boundary condition on the open-mode stress (radial tensile stress) and displacement fields in the curved sandwich panels. The critical stress point, where potential debonding failure could initiate, was found to be at the midspan (or outer span) of the inner bonding interface between the sandwich core and face sheet on the concave side, depending on the boundary condition and panel curvature. Open-mode stress increases with increasing panel curvature, reaching a maximum value at certain high curvature, and then decreases slightly as the panel curvature continues to increase and approach that of quarter circle. Changing the boundary condition from simply supported to clamped reduces the magnitudes of open-mode stresses and the associated sandwich core depth stretching.
Use of Semi-Autonomous Tools for ISS Commanding and Monitoring
NASA Technical Reports Server (NTRS)
Brzezinski, Amy S.
2014-01-01
As the International Space Station (ISS) has moved into a utilization phase, operations have shifted to become more ground-based with fewer mission control personnel monitoring and commanding multiple ISS systems. This shift to fewer people monitoring more systems has prompted use of semi-autonomous console tools in the ISS Mission Control Center (MCC) to help flight controllers command and monitor the ISS. These console tools perform routine operational procedures while keeping the human operator "in the loop" to monitor and intervene when off-nominal events arise. Two such tools, the Pre-positioned Load (PPL) Loader and Automatic Operators Recorder Manager (AutoORM), are used by the ISS Communications RF Onboard Networks Utilization Specialist (CRONUS) flight control position. CRONUS is responsible for simultaneously commanding and monitoring the ISS Command & Data Handling (C&DH) and Communications and Tracking (C&T) systems. PPL Loader is used to uplink small pieces of frequently changed software data tables, called PPLs, to ISS computers to support different ISS operations. In order to uplink a PPL, a data load command must be built that contains multiple user-input fields. Next, a multiple step commanding and verification procedure must be performed to enable an onboard computer for software uplink, uplink the PPL, verify the PPL has incorporated correctly, and disable the computer for software uplink. PPL Loader provides different levels of automation in both building and uplinking these commands. In its manual mode, PPL Loader automatically builds the PPL data load commands but allows the flight controller to verify and save the commands for future uplink. In its auto mode, PPL Loader automatically builds the PPL data load commands for flight controller verification, but automatically performs the PPL uplink procedure by sending commands and performing verification checks while notifying CRONUS of procedure step completion. If an off-nominal condition occurs during procedure execution, PPL Loader notifies CRONUS through popup messages, allowing CRONUS to examine the situation and choose an option of how PPL loader should proceed with the procedure. The use of PPL Loader to perform frequent, routine PPL uplinks offloads CRONUS to better monitor two ISS systems. It also reduces procedure performance time and decreases risk of command errors. AutoORM identifies ISS communication outage periods and builds commands to lock, playback, and unlock ISS Operations Recorder files. Operation Recorder files are circular buffer files of continually recorded ISS telemetry data. Sections of these files can be locked from further writing, be played back to capture telemetry data that occurred during an ISS loss of signal (LOS) period, and then be unlocked for future recording use. Downlinked Operation Recorder files are used by mission support teams for data analysis, especially if failures occur during LOS. The commands to lock, playback, and unlock Operations Recorder files are encompassed in three different operational procedures and contain multiple user-input fields. AutoORM provides different levels of automation for building and uplinking the commands to lock, playback, and unlock Operations Recorder files. In its automatic mode, AutoORM automatically detects ISS LOS periods, then generates and uplinks the commands to lock, playback, and unlock Operations Recorder files when MCC regains signal with ISS. AutoORM also features semi-autonomous and manual modes which integrate CRONUS more into the command verification and uplink process. AutoORMs ability to automatically detect ISS LOS periods and build the necessary commands to preserve, playback, and release recorded telemetry data greatly offloads CRONUS to perform more high-level cognitive tasks, such as mission planning and anomaly troubleshooting. Additionally, since Operations Recorder commands contain numerical time input fields which are tedious for a human to manually build, AutoORM's ability to automatically build commands reduces operational command errors. PPL Loader and AutoORM demonstrate principles of semi-autonomous operational tools that will benefit future space mission operations. Both tools employ different levels of automation to perform simple and routine procedures, thereby offloading human operators to perform higher-level cognitive tasks. Because both tools provide procedure execution status and highlight off-nominal indications, the flight controller is able to intervene during procedure execution if needed. Semi-autonomous tools and systems that can perform routine procedures, yet keep human operators informed of execution, will be essential in future long-duration missions where the onboard crew will be solely responsible for spacecraft monitoring and control.
Solbu, Kasper; Daae, Hanne Line; Thorud, Syvert; Ellingsen, Dag Gunnar; Lundanes, Elsa; Molander, Paal
2010-12-01
This study describes the potential for occupational exposure to organophosphates (OPs) originating from turbine and hydraulic oils, among ground personnel within the aviation industry. The OPs tri-n-butyl phosphate (TnBP), dibutyl phenyl phosphate (DBPP), triphenyl phosphate (TPP) and tricresyl phosphate (TCP) have been emphasized due to their use in such oils. Oil aerosol/vapor and total volatile organic compounds (tVOCs) in air were also determined. In total, 228 and 182 OPs and oil aerosol/vapor samples from technician and loader work tasks during work on 42 and 21 aircrafts, respectively, were collected in pairs. In general, the measured exposure levels were below the limit of quantification (LOQ) for 84%/98% (oil aerosol) and 82%/90% (TCP) of the samples collected during technician/loader work tasks. The air concentration ranges for all samples related to technician work were
2012-01-01
Once the swine were anesthetized, left cervical cut downs were performed and a central venous polyethylene catheter was inserted into the external...open and the liver injury will be examined for evidence of re-bleeding. The venous and arterial pressures at which re-bleeding occur will be...Fig. 1) Figure 1. Clamp used for the pig liver injury model The clamp is placed centrally in the liver and it produces laceration of 1
Characterization of the IEC 61000-4-6 Electromagnetic Clamp for Conducted-Immunity Testing
NASA Astrophysics Data System (ADS)
Grassi, F.; Pignari, S. A.; Spadacini, G.; Toscani, N.; Pelissou, P.
2016-05-01
A multiconductor transmission line model (MTL) is used to investigate the operation of the IEC 61000-4-6 electromagnetic (EM) clamp in a conducted-immunity test setup for aerospace applications. Aspects of interest include the performance of such a coupling device at very high frequencies (up to 1 GHz), and for extreme values of the common-mode impedance of equipment (short circuits, open circuits). The MTL model is finally exploited to predict the frequency response of coupling and decoupling factors defined in the IEC 61000-4-6 standard.
Dokos, J.A.
1997-12-30
A drill bit loader is described for loading a tapered shank of a drill bit into a similarly tapered recess in the end of a drill spindle. The spindle has a transverse slot at the inner end of the recess. The end of the tapered shank of the drill bit has a transverse tang adapted to engage in the slot so that the drill bit will be rotated by the spindle. The loader is in the form of a cylinder adapted to receive the drill bit with the shank projecting out of the outer end of the cylinder. Retainer pins prevent rotation of the drill bit in the cylinder. The spindle is lowered to extend the shank of the drill bit into the recess in the spindle and the spindle is rotated to align the slot in the spindle with the tang on the shank. A spring unit in the cylinder is compressed by the drill bit during its entry into the recess of the spindle and resiliently drives the tang into the slot in the spindle when the tang and slot are aligned. 5 figs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dokos, James A.
A drill bit loader for loading a tapered shank of a drill bit into a similarly tapered recess in the end of a drill spindle. The spindle has a transverse slot at the inner end of the recess. The end of the tapered shank of the drill bit has a transverse tang adapted to engage in the slot so that the drill bit will be rotated by the spindle. The loader is in the form of a cylinder adapted to receive the drill bit with the shank projecting out of the outer end of the cylinder. Retainer pins prevent rotationmore » of the drill bit in the cylinder. The spindle is lowered to extend the shank of the drill bit into the recess in the spindle and the spindle is rotated to align the slot in the spindle with the tang on the shank. A spring unit in the cylinder is compressed by the drill bit during its entry into the recess of the spindle and resiliently drives the tang into the slot in the spindle when the tang and slot are aligned.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dokos, J.A.
A drill bit loader is described for loading a tapered shank of a drill bit into a similarly tapered recess in the end of a drill spindle. The spindle has a transverse slot at the inner end of the recess. The end of the tapered shank of the drill bit has a transverse tang adapted to engage in the slot so that the drill bit will be rotated by the spindle. The loader is in the form of a cylinder adapted to receive the drill bit with the shank projecting out of the outer end of the cylinder. Retainer pinsmore » prevent rotation of the drill bit in the cylinder. The spindle is lowered to extend the shank of the drill bit into the recess in the spindle and the spindle is rotated to align the slot in the spindle with the tang on the shank. A spring unit in the cylinder is compressed by the drill bit during its entry into the recess of the spindle and resiliently drives the tang into the slot in the spindle when the tang and slot are aligned. 5 figs.« less
Sasmal, Dibyendu Kumar; Yadav, Rajeev; Lu, H Peter
2016-07-20
N-methyl-d-aspartate (NMDA) receptor ion channel is activated by the binding of two pairs of glycine and glutamate along with the application of action potential. Binding and unbinding of ligands changes its conformation that plays a critical role in the open-close activities of NMDA receptor. Conformation states and their dynamics due to ligand binding are extremely difficult to characterize either by conventional ensemble experiments or single-channel electrophysiology method. Here we report the development of a new correlated technical approach, single-molecule patch-clamp FRET anisotropy imaging and demonstrate by probing the dynamics of NMDA receptor ion channel and kinetics of glycine binding with its ligand binding domain. Experimentally determined kinetics of ligand binding with receptor is further verified by computational modeling. Single-channel patch-clamp and four-channel fluorescence measurement are recorded simultaneously to get correlation among electrical on and off states, optically determined conformational open and closed states by FRET, and binding-unbinding states of the glycine ligand by anisotropy measurement at the ligand binding domain of GluN1 subunit. This method has the ability to detect the intermediate states in addition to electrical on and off states. Based on our experimental results, we have proposed that NMDA receptor gating goes through at least one electrically intermediate off state, a desensitized state, when ligands remain bound at the ligand binding domain with the conformation similar to the fully open state.
Prototyping Faithful Execution in a Java virtual machine.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tarman, Thomas David; Campbell, Philip LaRoche; Pierson, Lyndon George
2003-09-01
This report presents the implementation of a stateless scheme for Faithful Execution, the design for which is presented in a companion report, ''Principles of Faithful Execution in the Implementation of Trusted Objects'' (SAND 2003-2328). We added a simple cryptographic capability to an already simplified class loader and its associated Java Virtual Machine (JVM) to provide a byte-level implementation of Faithful Execution. The extended class loader and JVM we refer to collectively as the Sandia Faithfully Executing Java architecture (or JavaFE for short). This prototype is intended to enable exploration of more sophisticated techniques which we intend to implement in hardware.
Pahlavan, Pedram; Najarian, Siamak; Afshari, Elnaz; Moini, Majid
2013-01-01
Artificial palpation is one of the most valuable achievements of artificial tactile sensing approach that can be used in various fields of medicine and more specifically in surgery. These techniques cause different surgical maneuvers to be done more precisely and noninvasively. In this study, considering the present problems and limitations of cross-clamping an artery during laparoscopic vascular surgeries, a new tactile sensory system will be introduced.Having imitated surgeon's palpation during open vascular surgeries and modeled it conceptually, the optimal amount of the total angular displacement of each robot joint in order to cross-clamping an artery without damaging to the artery surrounding tissues will be calculated. The elastic governing equation of contact occurred between the tactile sensor placed on the first link of the robot and the surrounding tissues around the artery were developed. A finite element model is coupled with genetic algorithm optimization method so that the normal stress and displacements in contact surface of the robot and artery's surrounding tissues would be minimized. Thus, reliability and accuracy of artificial tactile sensing method in artery cross-clamping will be demonstrated. Finally, the functional principles of the new tactile system capable of cross-clamping an artery during laparoscopic surgeries will be presented.
NASA Astrophysics Data System (ADS)
Helm, P. Johannes; Reppen, Trond; Heggelund, Paul
2009-02-01
Multi Photon Laser Scanning Microscopy (MPLSM) appears today as one of the most powerful experimental tools in cellular neurophysiology, notably in studies of the functional dynamics of signal processing in single neurons. Simultaneous recording of fluorescence signals at high spatial and temporal resolution and electric signals by means of multi electrode patch clamp techniques have provided new paths for the systematic investigation of neuronal mechanisms. In particular, this approach has opened for direct studies of dendritic signal processing in neurons. We report about a setup optimized for simultaneous electrophysiological multi electrode patch clamp and multi photon laser scanning fluorescence microscopic experiments on brain slices. The microscopic system is based on a modified commercially available confocal scanning laser microscope (CLSM). From a technical and operational point of view, two developments are important: Firstly, in order to reduce the workload for the experimentalist, who in general is forced to concentrate on controlling the electrophysiological parameters during the recordings, a system of shutters has been installed together with dedicated electronic modules protecting the photo detectors against destructive light levels caused by erroneous opening or closing of microscopic light paths by the experimentalist. Secondly, the standard detection unit has been improved by installing the photomultiplier tubes (PMT) in a Peltier cooled thermal box shielding the detector from both room temperature and distortions caused by external electromagnetic fields. The electrophysiological system is based on an industrial standard multi patch clamp unit ergonomically arranged around the microscope stage. The electrophysiological and scanning processes can be time coordinated by standard trigger electronics.
Synergistic Effect of Light and Fusicoccin on Stomatal Opening 1
Assmann, Sarah M.; Schwartz, Amnon
1992-01-01
Upon incubation of epidermal peels of Commelina communis in 1 millimolar KCl, a synergistic effect of light and low fusicoccin (FC) concentrations on stomatal opening is observed. In 1 millimolar KCl, stomata remain closed even in the light. However, addition of 0.1 micromolar FC results in opening up to 12 micrometers. The same FC concentration stimulates less than 5 micrometers of opening in darkness. The synergistic effect (a) decreases with increasing FC or KCl concentrations; (b) is dark-reversible; (c) like stomatal opening in high KCl concentrations (120 millimolar) is partially inhibited by the K+ channel blocker, tetraethyl-ammonium+ (20 millimolar). In whole-cell patch-clamp experiments with guard cell protoplasts of Vicia faba, FC (1 or 10 micromolar) stimulates an increase in outward current that is essentially voltage independent between - 100 and +60 millivolts, and occurs even when the membrane potential is held at a voltage (−60 millivolts) at which K+ channels are inactivated. These results are indicative of FC activation of a H+ pump. FC effects on the magnitude of inward and outward K+ currents are not observed. Epidermal peel and patch clamp data are both consistent with the hypothesis that the plasma membrane H+ ATPase of guard cells is a primary locus for the FC effect on stomatal apertures. PMID:16668799
An analysis of injuries to front-end loader operators during ingress and egress.
Nasarwanji, Mahiyar F; Pollard, Jonisha; Porter, William
2018-05-01
Slips, trips, and falls from mobile mining equipment have been documented for decades. However, little research has been conducted to determine the events precipitating these incidents during ingress or egress. This study examined slips, trips, and falls sustained during ingress or egress from front-end loaders to determine the frequencies of factors that may contribute to injuries. Non-fatal injuries, when getting on or off of front-end wheel loaders specifically, were identified, coded, and analyzed from the Mine Safety and Health Administration's accidents, injuries, and illnesses database. Overall trends, events that precipitated the injury, injuries sustained, contributing factors, location of the individual, and equipment characteristics were analyzed. More incidents occurred during egress (63%); and egress is believed to be more hazardous than ingress. Foot slips were the most common event that precipitated the incident and the leading cause of these was contaminants on the equipment. Misstep, loss of footing, and step on/in related incidents were more common during egress and are likely due to the operator's reduced visibility when descending a ladder facing the equipment, limiting their ability to detect hazards. Egress also makes an operator less capable of avoiding unsafe ground conditions as indicated by the significant number of step on/in injuries occurring on the ground during egress. Most of the front-end loaders associated with the incidents were found to have bottom rungs with flexible rails, which may also increase fall risk during egress due to inconsistent rung heights and lengthy transition areas from the ground, through the flexible-railed rungs, to the rungs with rigid rails. Recommendations are provided to reduce the risk for slips, trips, and falls from mobile mining equipment.
A patch clamp study on reconstituted calcium permeable channels of human sperm plasma membranes.
Ma, X H; Shi, Y L
1999-10-01
Ionic flux is thought to be important in the initiating process of gamete interaction such as acrosome reaction. However, modern electrophysiological methods, intracellular recording and patch-clamping, are difficult to approach the ion channels in mammal sperm membrane of an intact sperm due to its small size. In this work, by reconstituting the channel protein into lipid bilayer, Ca2+ channels in human spermatozoa were investigated with voltage clamp technique. Membrane proteins isolated from human sperm of 12 healthy donors were incorporated into lipid bilayer via fusion. In a cis 50//trans 10 mmol/L CaCl2 solution system, two types of channel events with similar reversal potential near the value of a perfect Ca2+ electrode, and sensitive to nifedipine and verapamil, were observed. Their unit conductance was 40 and 25 pS respectively. Percentage of channel open time was not dependent to holding potential for the former. However, for the channels of 25 pS, the percentage increased when the holding potential was changed from -20 to 100 mV. Ca(2+)-permeable channels were also detected from the spermatozoon samples of two infertile donors. Abnormal open time of these channels indicates that there are some defects in the conformation of the channel protein of infertile sperm membrane.
Newton, Robert G.
1977-01-01
The intermediate heat transport system for a sodium-cooled fast breeder reactor includes a device for rapidly draining the sodium therefrom should a sodium-water reaction occur within the system. This device includes a rupturable member in a drain line in the system and means for cutting a large opening therein and for positively removing the sheared-out portion from the opening cut in the rupturable member. According to the preferred embodiment of the invention the rupturable member includes a solid head seated in the end of the drain line having a rim extending peripherally therearound, the rim being clamped against the end of the drain line by a clamp ring having an interior shearing edge, the bottom of the rupturable member being convex and extending into the drain line. Means are provided to draw the rupturable member away from the drain line against the shearing edge to clear the drain line for outflow of sodium therethrough.
Campagnola, Luke; Kratz, Megan B; Manis, Paul B
2014-01-01
The complexity of modern neurophysiology experiments requires specialized software to coordinate multiple acquisition devices and analyze the collected data. We have developed ACQ4, an open-source software platform for performing data acquisition and analysis in experimental neurophysiology. This software integrates the tasks of acquiring, managing, and analyzing experimental data. ACQ4 has been used primarily for standard patch-clamp electrophysiology, laser scanning photostimulation, multiphoton microscopy, intrinsic imaging, and calcium imaging. The system is highly modular, which facilitates the addition of new devices and functionality. The modules included with ACQ4 provide for rapid construction of acquisition protocols, live video display, and customizable analysis tools. Position-aware data collection allows automated construction of image mosaics and registration of images with 3-dimensional anatomical atlases. ACQ4 uses free and open-source tools including Python, NumPy/SciPy for numerical computation, PyQt for the user interface, and PyQtGraph for scientific graphics. Supported hardware includes cameras, patch clamp amplifiers, scanning mirrors, lasers, shutters, Pockels cells, motorized stages, and more. ACQ4 is available for download at http://www.acq4.org.
Morelli, Luca; Morelli, John; Palmeri, Matteo; D'Isidoro, Cristiano; Kauffmann, Emanuele Federico; Tartaglia, Dario; Caprili, Giovanni; Pisano, Roberta; Guadagni, Simone; Di Franco, Gregorio; Di Candio, Giulio; Mosca, Franco
2015-09-01
Robot-assisted partial nephrectomy has been proposed as a technique to overcome technical challenges of laparoscopic partial nephrectomy. We prospectively collected and analyzed data from 31 patients who underwent robotic partial nephrectomy with systematic use of hemostatic agents, between February 2009 and October 2014. Thirty-three renal tumors were treated in 31 patients. There were no conversions to open surgery, intraoperative complications, or blood transfusions. The mean size of the resected tumors was 27 mm (median 20 mm, range 5-40 mm). Twenty-seven of 33 lesions (82%) did not require vascular clamping and therefore were treated in the absence of ischemia. All margins were negative. The high partial nephrectomy success rate without vascular clamping suggests that robotic nephron-sparing surgery with systematic use of hemostatic agents may be a safe, effective method to completely avoid ischemia in the treatment of selected renal masses.
Modelling and study of active vibration control for off-road vehicle
NASA Astrophysics Data System (ADS)
Zhang, Junwei; Chen, Sizhong
2014-05-01
In view of special working characteristics and structure, engineering machineries do not have conventional suspension system typically. Consequently, operators have to endure severe vibrations which are detrimental both to their health and to the productivity of the loader. Based on displacement control, a kind of active damping method is developed for a skid-steer loader. In this paper, the whole hydraulic system for active damping method is modelled which include swash plate dynamics model, proportional valve model, piston accumulator model, pilot-operated check valve model, relief valve model, pump loss model, and cylinder model. A new road excitation model is developed for the skid-steer loader specially. The response of chassis vibration acceleration to road excitation is verified through simulation. The simulation result of passive accumulator damping is compared with measurements and the comparison shows that they are close. Based on this, parallel PID controller and track PID controller with acceleration feedback are brought into the simulation model, and the simulation results are compared with passive accumulator damping. It shows that the active damping methods with PID controllers are better in reducing chassis vibration acceleration and pitch movement. In the end, the test work for active damping method is proposed for the future work.
A One-Hand Nut and Bolt Assembly Tool
NASA Technical Reports Server (NTRS)
Spencer, J. M.
1984-01-01
Special wrench speeds nut and bolt assembly when insufficient room to hold nut behind bolthole with standard tool. C-clamp shaped box-andsocket-wrench assembly holds nut on blind side in alinement to receive bolt from open side.
Dendrimer-assisted patch-clamp sizing of nuclear pores
Bustamante, J.O.; Michelette, E.R.F.; Geibel, J.P.; Hanover, J.A.; McDonnell, T.J.; Dean, D.A.
2015-01-01
Macromolecular translocation (MMT) across the nuclear envelope (NE) occurs exclusively through the nuclear pore complex (NPC). Therefore, the diameter of the NPC aqueous/electrolytic channel (NPCC) is important for cellular structure and function. The NPCC diameter was previously determined to be ≅10 nm with electron microscopy (EM) using the translocation of colloidal gold particles. Here we present patch-clamp and fluorescence microscopy data from adult cardiomyocyte nuclei that demonstrate the use of patch-clamp for assessing NPCC diameter. Fluorescence microscopy with B-phycoerythrin (BPE, 240 kDa) conjugated to a nuclear localization signal (NLS) demonstrated that these nuclei were competent for NPC-mediated MMT (NPC-MMT). Furthermore, when exposed to an appropriate cell lysate, the nuclei expressed enhanced green fluorescence protein (EGFP) after 5–10 h of incubation with the plasmid for this protein (pEGFP, 3.1 MDa). Nucleus-attached patch-clamp showed that colloidal gold particles were not useful probes; they modified NPCC gating. As a result of this finding, we searched for an inert class of particles that could be used without irreversibly affecting NPCC gating and found that fluorescently labeled Star-burst dendrimers, a distinct class of polymers, were useful. Our patch-clamp and fluorescence microscopy data with calibrated dendrimers indicate that the cardiomyocyte NPCC diameter varies between 8 and 9 nm. These studies open a new direction in the investigation of live, continuous NPC dynamics under physiological conditions. PMID:10784359
Lewan, Michael D.; Birdwell, Justin E.; Baez, Luis; Beeney, Ken; Sonnenberg, Steve
2013-01-01
Understanding changes in petrophysical and geochemical parameters during source rock thermal maturation is a critical component in evaluating source-rock petroleum accumulations. Natural core data are preferred, but obtaining cores that represent the same facies of a source rock at different thermal maturities is seldom possible. An alternative approach is to induce thermal maturity changes by laboratory pyrolysis on aliquots of a source-rock sample of a given facies of interest. Hydrous pyrolysis is an effective way to induce thermal maturity on source-rock cores and provide expelled oils that are similar in composition to natural crude oils. However, net-volume increases during bitumen and oil generation result in expanded cores due to opening of bedding-plane partings. Although meaningful geochemical measurements on expanded, recovered cores are possible, the utility of the core for measuring petrophysical properties relevant to natural subsurface cores is not suitable. This problem created during hydrous pyrolysis is alleviated by using a stainless steel uniaxial confinement clamp on rock cores cut perpendicular to bedding fabric. The clamp prevents expansion just as overburden does during natural petroleum formation in the subsurface. As a result, intact cores can be recovered at various thermal maturities for the measurement of petrophysical properties as well as for geochemical analyses. This approach has been applied to 1.7-inch diameter cores taken perpendicular to the bedding fabric of a 2.3- to 2.4-inch thick slab of Mahogany oil shale from the Eocene Green River Formation. Cores were subjected to hydrous pyrolysis at 360 °C for 72 h, which represents near maximum oil generation. One core was heated unconfined and the other was heated in the uniaxial confinement clamp. The unconfined core developed open tensile fractures parallel to the bedding fabric that result in a 38 % vertical expansion of the core. These open fractures did not occur in the confined core, but short, discontinuous vertical fractures on the core periphery occurred as a result of lateral expansion.
NASA Technical Reports Server (NTRS)
Collins, J. Scott; Johnson, Eric R.
1989-01-01
Experiments were conducted to measure the three-dimensional static and free vibrational response of two graphite-epoxy, thin-walled, open section frames. The frames are semi-circular with a radius of three feet, and one specimen has an I cross section and the other has a channel cross section. The flexibility influence coefficients were measured in static tests for loads applied at midspan with the ends of the specimens clamped. Natural frequencies and modes were determined from vibrational tests for free and clamped end conditions. The experimental data is used to evaluate a new finite element which was developed specifically for the analysis of curved, thin-walled structures. The formulation of the element is based on a Vlasov-type, thin-walled, curved beam theory. The predictions from the finite element program generally correlated well with the experimental data for the symmetric I-specimen. Discrepancies in some of the data were found to be due to flexibility in the clamped end conditions. With respect to the data for the channel specimen, the correlation was less satisfactory. The finite element analysis predicted the out-of-plane response of the channel specimen reasonably well, but large discrepancies occurred between the predicted in-plane response and the experimental data. The analysis predicted a much more compliant in-plane response than was observed in the experiments.
Signal presequences increase mitochondrial permeability and open the multiple conductance channel.
Kushnareva, Y E; Campo, M L; Kinnally, K W; Sokolove, P M
1999-06-01
We have reported that the signal presequence of cytochrome oxidase subunit IV from Neurospora crassa increases the permeability of isolated rat liver mitochondria [P. M. Sokolove and K. W. Kinnally (1996) Arch. Biochem. Biophys. 336, 69] and regulates the behavior of the mutiple conductance channel (MCC) of yeast inner mitochondrial membrane [T. A. Lohret and K. W. Kinnally (1995) J. Biol. Chem. 270, 15950]. Here we examine in greater detail the action of a number of mitochondrial presequences from various sources and of several control peptides on the permeability of isolated rat liver mitochondria and on MCC activity monitored via patch-clamp techniques in both mammalian mitoplasts and a reconstituted yeast system. The data indicate that the ability to alter mitochondrial permeability is a property of most, but not all, signal peptides. Furthermore, it is clear that, although signal peptides are characterized by positive charge and the ability to form amphiphilic alpha helices, these two characteristics are not sufficient to guarantee mitochondrial effects. Finally, the results reveal a strong correlation between peptide effects on the permeability of isolated mitochondria and on MCC activity: peptides that induced swelling of mouse and rat mitochondria also activated the quiescent MCC of mouse mitoplasts and induced flickering of active MCC reconstituted from yeast mitochondrial membranes. Moreover, relative peptide efficacies were very similar for mitochondrial swelling and both types of patch-clamp experiments. We propose that patch-clamp recordings of MCC activity and the high-amplitude swelling induced by signal peptides reflect the opening of a single channel. Based on the selective responsiveness of that channel to signal peptides and the dependence of its opening in isolated mitochondria on membrane potential, we further suggest that the channel is involved in the mitochondrial protein import process. Copyright 1999 Academic Press.
Lindgren, Emma; Hägg, Sara; Giordano, Fosco; Björkegren, Johan; Ström, Lena
2014-01-01
Genome integrity is fundamental for cell survival and cell cycle progression. Important mechanisms for keeping the genome intact are proper sister chromatid segregation, correct gene regulation and efficient repair of damaged DNA. Cohesin and its DNA loader, the Scc2/4 complex have been implicated in all these cellular actions. The gene regulation role has been described in several organisms. In yeast it has been suggested that the proteins in the cohesin network would effect transcription based on its role as insulator. More recently, data are emerging indicating direct roles for gene regulation also in yeast. Here we extend these studies by investigating whether the cohesin loader Scc2 is involved in regulation of gene expression. We performed global gene expression profiling in the absence and presence of DNA damage, in wild type and Scc2 deficient G2/M arrested cells, when it is known that Scc2 is important for DNA double strand break repair and formation of damage induced cohesion. We found that not only the DNA damage specific transcriptional response is distorted after inactivation of Scc2 but also the overall transcription profile. Interestingly, these alterations did not correlate with changes in cohesin binding. PMID:25483075
Apparatus for unloading nuclear fuel pellets from a sintering boat
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bucher, G.D.; Raymond, T.E.
1987-02-10
An apparatus is described for unloading nuclear fuel pellets from a loaded sintering boat having an open top, comprising: (a) means for receiving the boat in an upright position with the pellets contained therein, the boat receiving means including a platform for supporting the loaded boat in the upright position, the boat supporting platform having first and second portions; (b) means for clamping the boat including a pair of plates disposed at lateral sides of the boat and being movable in a first direction relative to one another for applying clamping forces to the boat on the platform and inmore » a second direction relative to one another for releasing the clamping forces from the boat. The pair of plates have inner surfaces facing toward one another, the first and second platform portions of the boat supporting platform being mounted to the plates on the respective facing surfaces thereof and disposed in a common plane. One of the plates and one of the platform portions mounted thereto are disposed in a stationary position and the other of the plates and the other of the platform portions mounted thereto are movable relative thereto in the first and second directions for applying and releasing clamping forces to and from the boat while the boat is supported in the upright position by the platform portions; (c) means for transferring the clamped boat from the upright position to an inverted position and then back to the upright position; and (d) means of receiving the pellets from the clamped boat as the boat is being transferred from the upright position to the inverted position.« less
Kamiyama, Yoshihiro; Yamashita, Shinichi; Nakagawa, Atsuhiro; Fujii, Shinji; Mitsuzuka, Koji; Kaiho, Yasuhiro; Ito, Akihiro; Abe, Takaaki; Tominaga, Teiji; Arai, Yoichi
2017-09-01
In the setting of partial nephrectomy (PN) for renal cell carcinoma, postoperative renal dysfunction might be caused by surgical procedure. The aim of this study was to clarify the technical safety and renal damage after off-clamp laparoscopic PN (LPN) with a piezo actuator-driven pulsed water jet (ADPJ) system. Eight swine underwent off-clamp LPN with this surgical device, while off-clamp open PN was also performed with radio knife or soft coagulation. The length of the removed kidney was 40 mm, and the renal parenchyma was dissected until the renal calyx became clearly visible. The degree of renal degeneration from the resection surface was compared by Hematoxylin-Eosin staining and immunostaining for 1-methyladenosine, a sensitive marker for the ischemic tissue damage. The mRNA levels of neutrophil gelatinase-associated lipocalin (Ngal), a biomarker for acute kidney injury, were measured by quantitative real-time PCR. Off-clamp LPN with ADPJ system was successfully performed while preserving fine blood vessels and the renal calix with little bleeding. In contrast to other devices, the resection surface obtained with the ADPJ system showed only marginal degree of ischemic changes. Indeed, the expression level of Ngal mRNA was lower in the resection surface obtained with the ADPJ system than that with soft coagulation (p = 0.02). Furthermore, using the excised specimens of renal cell carcinoma, we measured the breaking strength at each site of the human kidney, suggesting the applicability of this ADPJ to clinical trials. In conclusion, off-clamp LPN with the ADPJ system could be safely performed with attenuated renal damage.
Wilson, John; Docherty, Paul; Stubbs, Richard; Chase, J Geoffrey; Krebs, Jeremy
2018-06-11
To compare the dynamic insulin secretion and sensitivity test (DISST) with the euglycaemic clamp in individuals undergoing open Roux-en-Y gastric bypass (RYGB) surgery prior-to and one month after surgery. Insulin sensitivity in individuals with obesity undergoing RYGB was studied with DISST and a euglycaemic hyperinsulinaemic clamp. Eleven participants, including nine females, mean(SD) age 51.2(12.1)yrs, with a preoperative BMI of 48.7(9.5)kg/m 2 were studied. Weight reduced from a mean(SD) of 133.8(29.8)kg to 123.8(28.9)kg post-surgery (p<0.001). The mean(SD) insulin sensitivity index (ISI-DISST) was 3.07×10 -4 (2.18)L.pmol -1 .min -1 preoperatively and 2.36 ×10 -4 (0.78)L.pmol -1 .min -1 postoperatively (p=0.37). The mean(SD) clamp ISI was 2.14 ×10 -2 (1.80)mg.L.kg -1 .min -1 .pmol -1 and 2.00×10 -2 .(0.76)mg.L.kg -1 .min -1 .pmol -1 postoperatively (p=0.86). Correlation between ISI-DISST and ISI-Clamp preoperatively was r=0.81(95%CI 0.37-0.95) and post-operatively r=0.47(95%CI 0-0.88). Bland-Altman analysis demonstrates systematic bias between the two tests, where DISST underestimated insulin sensitivity compared with the clamp by 0.96×10 -2 .mg.L.kg -1 .min -1 .pmol -1 (95%CI -2.24 to 0.32). There was a strong correlation between DISST and the clamp preoperatively and DISST can be used to estimate insulin sensitivity in individuals with morbid obesity. After RYGB surgery, DISST had a weaker correlation with the clamp suggesting the fundamental physiological determinants of insulin sensitivity being measured by each method change in different ways with changes in glucose homeostasis following RYGB surgery. © Georg Thieme Verlag KG Stuttgart · New York.
ACQ4: an open-source software platform for data acquisition and analysis in neurophysiology research
Campagnola, Luke; Kratz, Megan B.; Manis, Paul B.
2014-01-01
The complexity of modern neurophysiology experiments requires specialized software to coordinate multiple acquisition devices and analyze the collected data. We have developed ACQ4, an open-source software platform for performing data acquisition and analysis in experimental neurophysiology. This software integrates the tasks of acquiring, managing, and analyzing experimental data. ACQ4 has been used primarily for standard patch-clamp electrophysiology, laser scanning photostimulation, multiphoton microscopy, intrinsic imaging, and calcium imaging. The system is highly modular, which facilitates the addition of new devices and functionality. The modules included with ACQ4 provide for rapid construction of acquisition protocols, live video display, and customizable analysis tools. Position-aware data collection allows automated construction of image mosaics and registration of images with 3-dimensional anatomical atlases. ACQ4 uses free and open-source tools including Python, NumPy/SciPy for numerical computation, PyQt for the user interface, and PyQtGraph for scientific graphics. Supported hardware includes cameras, patch clamp amplifiers, scanning mirrors, lasers, shutters, Pockels cells, motorized stages, and more. ACQ4 is available for download at http://www.acq4.org. PMID:24523692
Command-line cellular electrophysiology for conventional and real-time closed-loop experiments.
Linaro, Daniele; Couto, João; Giugliano, Michele
2014-06-15
Current software tools for electrophysiological experiments are limited in flexibility and rarely offer adequate support for advanced techniques such as dynamic clamp and hybrid experiments, which are therefore limited to laboratories with a significant expertise in neuroinformatics. We have developed lcg, a software suite based on a command-line interface (CLI) that allows performing both standard and advanced electrophysiological experiments. Stimulation protocols for classical voltage and current clamp experiments are defined by a concise and flexible meta description that allows representing complex waveforms as a piece-wise parametric decomposition of elementary sub-waveforms, abstracting the stimulation hardware. To perform complex experiments lcg provides a set of elementary building blocks that can be interconnected to yield a large variety of experimental paradigms. We present various cellular electrophysiological experiments in which lcg has been employed, ranging from the automated application of current clamp protocols for characterizing basic electrophysiological properties of neurons, to dynamic clamp, response clamp, and hybrid experiments. We finally show how the scripting capabilities behind a CLI are suited for integrating experimental trials into complex workflows, where actual experiment, online data analysis and computational modeling seamlessly integrate. We compare lcg with two open source toolboxes, RTXI and RELACS. We believe that lcg will greatly contribute to the standardization and reproducibility of both simple and complex experiments. Additionally, on the long run the increased efficiency due to a CLI will prove a great benefit for the experimental community. Copyright © 2014 Elsevier B.V. All rights reserved.
A scalable database model for multiparametric time series: a volcano observatory case study
NASA Astrophysics Data System (ADS)
Montalto, Placido; Aliotta, Marco; Cassisi, Carmelo; Prestifilippo, Michele; Cannata, Andrea
2014-05-01
The variables collected by a sensor network constitute a heterogeneous data source that needs to be properly organized in order to be used in research and geophysical monitoring. With the time series term we refer to a set of observations of a given phenomenon acquired sequentially in time. When the time intervals are equally spaced one speaks of period or sampling frequency. Our work describes in detail a possible methodology for storage and management of time series using a specific data structure. We designed a framework, hereinafter called TSDSystem (Time Series Database System), in order to acquire time series from different data sources and standardize them within a relational database. The operation of standardization provides the ability to perform operations, such as query and visualization, of many measures synchronizing them using a common time scale. The proposed architecture follows a multiple layer paradigm (Loaders layer, Database layer and Business Logic layer). Each layer is specialized in performing particular operations for the reorganization and archiving of data from different sources such as ASCII, Excel, ODBC (Open DataBase Connectivity), file accessible from the Internet (web pages, XML). In particular, the loader layer performs a security check of the working status of each running software through an heartbeat system, in order to automate the discovery of acquisition issues and other warning conditions. Although our system has to manage huge amounts of data, performance is guaranteed by using a smart partitioning table strategy, that keeps balanced the percentage of data stored in each database table. TSDSystem also contains modules for the visualization of acquired data, that provide the possibility to query different time series on a specified time range, or follow the realtime signal acquisition, according to a data access policy from the users.
A multidisciplinary database for geophysical time series management
NASA Astrophysics Data System (ADS)
Montalto, P.; Aliotta, M.; Cassisi, C.; Prestifilippo, M.; Cannata, A.
2013-12-01
The variables collected by a sensor network constitute a heterogeneous data source that needs to be properly organized in order to be used in research and geophysical monitoring. With the time series term we refer to a set of observations of a given phenomenon acquired sequentially in time. When the time intervals are equally spaced one speaks of period or sampling frequency. Our work describes in detail a possible methodology for storage and management of time series using a specific data structure. We designed a framework, hereinafter called TSDSystem (Time Series Database System), in order to acquire time series from different data sources and standardize them within a relational database. The operation of standardization provides the ability to perform operations, such as query and visualization, of many measures synchronizing them using a common time scale. The proposed architecture follows a multiple layer paradigm (Loaders layer, Database layer and Business Logic layer). Each layer is specialized in performing particular operations for the reorganization and archiving of data from different sources such as ASCII, Excel, ODBC (Open DataBase Connectivity), file accessible from the Internet (web pages, XML). In particular, the loader layer performs a security check of the working status of each running software through an heartbeat system, in order to automate the discovery of acquisition issues and other warning conditions. Although our system has to manage huge amounts of data, performance is guaranteed by using a smart partitioning table strategy, that keeps balanced the percentage of data stored in each database table. TSDSystem also contains modules for the visualization of acquired data, that provide the possibility to query different time series on a specified time range, or follow the realtime signal acquisition, according to a data access policy from the users.
BioWarehouse: a bioinformatics database warehouse toolkit
Lee, Thomas J; Pouliot, Yannick; Wagner, Valerie; Gupta, Priyanka; Stringer-Calvert, David WJ; Tenenbaum, Jessica D; Karp, Peter D
2006-01-01
Background This article addresses the problem of interoperation of heterogeneous bioinformatics databases. Results We introduce BioWarehouse, an open source toolkit for constructing bioinformatics database warehouses using the MySQL and Oracle relational database managers. BioWarehouse integrates its component databases into a common representational framework within a single database management system, thus enabling multi-database queries using the Structured Query Language (SQL) but also facilitating a variety of database integration tasks such as comparative analysis and data mining. BioWarehouse currently supports the integration of a pathway-centric set of databases including ENZYME, KEGG, and BioCyc, and in addition the UniProt, GenBank, NCBI Taxonomy, and CMR databases, and the Gene Ontology. Loader tools, written in the C and JAVA languages, parse and load these databases into a relational database schema. The loaders also apply a degree of semantic normalization to their respective source data, decreasing semantic heterogeneity. The schema supports the following bioinformatics datatypes: chemical compounds, biochemical reactions, metabolic pathways, proteins, genes, nucleic acid sequences, features on protein and nucleic-acid sequences, organisms, organism taxonomies, and controlled vocabularies. As an application example, we applied BioWarehouse to determine the fraction of biochemically characterized enzyme activities for which no sequences exist in the public sequence databases. The answer is that no sequence exists for 36% of enzyme activities for which EC numbers have been assigned. These gaps in sequence data significantly limit the accuracy of genome annotation and metabolic pathway prediction, and are a barrier for metabolic engineering. Complex queries of this type provide examples of the value of the data warehousing approach to bioinformatics research. Conclusion BioWarehouse embodies significant progress on the database integration problem for bioinformatics. PMID:16556315
BioWarehouse: a bioinformatics database warehouse toolkit.
Lee, Thomas J; Pouliot, Yannick; Wagner, Valerie; Gupta, Priyanka; Stringer-Calvert, David W J; Tenenbaum, Jessica D; Karp, Peter D
2006-03-23
This article addresses the problem of interoperation of heterogeneous bioinformatics databases. We introduce BioWarehouse, an open source toolkit for constructing bioinformatics database warehouses using the MySQL and Oracle relational database managers. BioWarehouse integrates its component databases into a common representational framework within a single database management system, thus enabling multi-database queries using the Structured Query Language (SQL) but also facilitating a variety of database integration tasks such as comparative analysis and data mining. BioWarehouse currently supports the integration of a pathway-centric set of databases including ENZYME, KEGG, and BioCyc, and in addition the UniProt, GenBank, NCBI Taxonomy, and CMR databases, and the Gene Ontology. Loader tools, written in the C and JAVA languages, parse and load these databases into a relational database schema. The loaders also apply a degree of semantic normalization to their respective source data, decreasing semantic heterogeneity. The schema supports the following bioinformatics datatypes: chemical compounds, biochemical reactions, metabolic pathways, proteins, genes, nucleic acid sequences, features on protein and nucleic-acid sequences, organisms, organism taxonomies, and controlled vocabularies. As an application example, we applied BioWarehouse to determine the fraction of biochemically characterized enzyme activities for which no sequences exist in the public sequence databases. The answer is that no sequence exists for 36% of enzyme activities for which EC numbers have been assigned. These gaps in sequence data significantly limit the accuracy of genome annotation and metabolic pathway prediction, and are a barrier for metabolic engineering. Complex queries of this type provide examples of the value of the data warehousing approach to bioinformatics research. BioWarehouse embodies significant progress on the database integration problem for bioinformatics.
Batashev, Denis R.; Pakhomova, Marina V.; Razumovskaya, Anna V.; Voitsekhovskaja, Olga V.; Gamalei, Yuri V.
2013-01-01
The discovery of abundant plasmodesmata at the bundle sheath/phloem interface in Oleaceae (Gamalei, 1974) and Cucurbitaceae (Turgeon et al., 1975) raised the questions as to whether these plasmodesmata are functional in phloem loading and how widespread symplasmic loading would be. Analysis of over 800 dicot species allowed the definition of “open” and “closed” types of the minor vein phloem depending on the abundance of plasmodesmata between companion cells and bundle sheath (Gamalei, 1989, 1990). These types corresponded to potential symplasmic and apoplasmic phloem loaders, respectively; however, this definition covered a spectrum of diverse structures of phloem endings. Here, a review of detailed cytological analyses of minor veins in 320 species from the subclass Asteridae is presented, including data on companion cell types and their combinations which have not been reported previously. The percentage of Asteridae species with “open” minor vein cytology which also contain sieve-element-companion cell complexes with “closed” cytology, i.e., that show specialization for both symplasmic and apoplasmic phloem loading, was determined. Along with recent data confirming the dissimilar functional specialization of structurally different parts of minor vein phloem in the stachyose-translocating species Alonsoa meridionalis (Voitsekhovskaja et al., 2009), these findings suggest that apoplasmic loading is indispensable in a large group of species previously classified as putative symplasmic loaders. Altogether, this study provides formal classifications of companion cells and of minor veins, respectively, in 24 families of the Asteridae based on their structural features, opening the way to a close investigation of the relationship between structure and function in phloem loading. PMID:23970890
Dynamics of internal pore opening in KV channels probed by a fluorescent unnatural amino acid
Kalstrup, Tanja; Blunck, Rikard
2013-01-01
Atomic-scale models on the gating mechanism of voltage-gated potassium channels (Kv) are based on linear interpolations between static structures of their initial and final state derived from crystallography and molecular dynamics simulations, and, thus, lack dynamic structural information. The lack of information on dynamics and intermediate states makes it difficult to associate the structural with the dynamic functional data obtained with electrophysiology. Although voltage-clamp fluorometry fills this gap, it is limited to sites extracellularly accessible, when the key region for gating is located at the cytosolic side of the channels. Here, we solved this problem by performing voltage-clamp fluorometry with a fluorescent unnatural amino acid. By using an orthogonal tRNA-synthetase pair, the fluorescent unnatural amino acid was incorporated in the Shaker voltage-gated potassium channel at key regions that were previously inaccessible. Thus, we defined which parts act independently and which parts act cooperatively and found pore opening to occur in two sequential transitions. PMID:23630265
Besch, Stephen R; Suchyna, Thomas; Sachs, Frederick
2002-10-01
We built a high-speed, pneumatic pressure clamp to stimulate patch-clamped membranes mechanically. The key control element is a newly designed differential valve that uses a single, nickel-plated piezoelectric bending element to control both pressure and vacuum. To minimize response time, the valve body was designed with minimum dead volume. The result is improved response time and stability with a threefold decrease in actuation latency. Tight valve clearances minimize the steady-state air flow, permitting us to use small resonant-piston pumps to supply pressure and vacuum. To protect the valve from water contamination in the event of a broken pipette, an optical sensor detects water entering the valve and increases pressure rapidly to clear the system. The open-loop time constant for pressure is 2.5 ms for a 100-mmHg step, and the closed-loop settling time is 500-600 micros. Valve actuation latency is 120 micros. The system performance is illustrated for mechanically induced changes in patch capacitance.
NASA Astrophysics Data System (ADS)
Biały, Witold
2017-06-01
Failure frequency in the mining process, with a focus on the mining machine, has been presented and illustrated by the example of two coal-mines. Two mining systems have been subjected to analysis: a cutter-loader and a plough system. In order to reduce costs generated by failures, maintenance teams should regularly make sure that the machines are used and operated in a rational and effective way. Such activities will allow downtimes to be reduced, and, in consequence, will increase the effectiveness of a mining plant. The evaluation of mining machines' failure frequency contained in this study has been based on one of the traditional quality management tools - the Pareto chart.
US Army Armor Reference Data in Three Volumes. Volume II. Nondivisional Organizations.
1981-01-01
SQuat 1r) R 2 SGI IB20 (Team Ldr) R I SP4 19GIO (Loader/Gnr) P I SP5 19G20 (St Gunner) P 1 t,5 19G20 (Sr Gunner) P I SP4 IICII ()Carrrr Dv) P 2 SP4 11810...Sergeant 2 SP4 Mat Storage Sp 1 SIC Platoon SOT1 SPC Food Svc SGT 1 SP4 Supply Con & Acct Cik 1 SP4 Lt Veh DriverI SFC Motor Sergeant I SP4 Subsistence...PLATOON Ho-.-- Loader Scoop Type 2-1/2 CU YD .Platoon Leader Tank Fabric Fuel 10,000-Gal. 1 SPC Platoon SC? 1 PFlC Reports Clerk 0lRadio Set N/VRC-46
DETAIL VIEW OF TRAM BUCKET FRAME, SHOWING CLAMPING MECHANISM,WITHOUT ORE ...
DETAIL VIEW OF TRAM BUCKET FRAME, SHOWING CLAMPING MECHANISM,WITHOUT ORE BUCKET AND WHEELS. THE FRAME IS LYING ON ITS SIDE. THE ORE BUCKET WAS ATTACHED TO THE LEFT SIDE, AND TWO WHEELS WERE ATTACHED TO THE SPINDLE ON THE RIGHT. THE FRAME AND BUCKET ARE SUSPENDED FROM THE STATIONARY CABLE BY THE TWO WHEELS, WITH THE ORE BUCKET HANGING BELOW. THE WHEEL AND LEVER AT CENTER WERE ACTIVATED BY THE OPENING AND CLOSING MECHANISMS ON THE TRAM TERMINALS TO LOCK OR RELEASE THE BUCKET ONTO THE MOVING CABLE THAT RAN THROUGH THE SQUARE BLOCK AT CENTER. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA
Antagonism of Lidocaine Inhibition by Open-Channel Blockers That Generate Resurgent Na Current
Bant, Jason S.; Aman, Teresa K.; Raman, Indira M.
2013-01-01
Na channels that generate resurgent current express an intracellular endogenous open-channel blocking protein, whose rapid binding upon depolarization and unbinding upon repolarization minimizes fast and slow inactivation. Na channels also bind exogenous compounds, such as lidocaine, which functionally stabilize inactivation. Like the endogenous blocking protein, these use-dependent inhibitors bind most effectively at depolarized potentials, raising the question of how lidocaine-like compounds affect neurons with resurgent Na current. We therefore recorded lidocaine inhibition of voltage-clamped, tetrodotoxin-sensitive Na currents in mouse Purkinje neurons, which express a native blocking protein, and in mouse hippocampal CA3 pyramidal neurons with and without a peptide from the cytoplasmic tail of NaVβ4 (the β4 peptide), which mimics endogenous open-channel block. To control channel states during drug exposure, lidocaine was applied with rapid-solution exchange techniques during steps to specific voltages. Inhibition of Na currents by lidocaine was diminished by either the β4 peptide or the native blocking protein. In peptide-free CA3 cells, prolonging channel opening with a site-3 toxin, anemone toxin II, reduced lidocaine inhibition; this effect was largely occluded by open-channel blockers, suggesting that lidocaine binding is favored by inactivation but prevented by open-channel block. In constant 100 μM lidocaine, current-clamped Purkinje cells continued to fire spontaneously. Similarly, the β4 peptide reduced lidocaine-dependent suppression of spiking in CA3 neurons in slices. Thus, the open-channel blocking protein responsible for resurgent current acts as a natural antagonist of lidocaine. Neurons with resurgent current may therefore be less susceptible to use-dependent Na channel inhibitors used as local anesthetic, antiarrhythmic, and anticonvulsant drugs. PMID:23486968
30 CFR 77.1109 - Quantity and location of firefighting equipment.
Code of Federal Regulations, 2010 CFR
2010-07-01
... construction. (c)(1) Mobile equipment, including trucks, front-end loaders, bulldozers, portable welding units...) Fire extinguishers shall be provided at permanent electrical installations commensurate with the...
Osmotic mechanism of the loop extrusion process
NASA Astrophysics Data System (ADS)
Yamamoto, Tetsuya; Schiessel, Helmut
2017-09-01
The loop extrusion theory assumes that protein factors, such as cohesin rings, act as molecular motors that extrude chromatin loops. However, recent single molecule experiments have shown that cohesin does not show motor activity. To predict the physical mechanism involved in loop extrusion, we here theoretically analyze the dynamics of cohesin rings on a loop, where a cohesin loader is in the middle and unloaders at the ends. Cohesin monomers bind to the loader rather frequently and cohesin dimers bind to this site only occasionally. Our theory predicts that a cohesin dimer extrudes loops by the osmotic pressure of cohesin monomers on the chromatin fiber between the two connected rings. With this mechanism, the frequency of the interactions between chromatin segments depends on the loading and unloading rates of dimers at the corresponding sites.
The accident analysis of mobile mine machinery in Indian opencast coal mines.
Kumar, R; Ghosh, A K
2014-01-01
This paper presents the analysis of large mining machinery related accidents in Indian opencast coal mines. The trends of coal production, share of mining methods in production, machinery deployment in open cast mines, size and population of machinery, accidents due to machinery, types and causes of accidents have been analysed from the year 1995 to 2008. The scrutiny of accidents during this period reveals that most of the responsible factors are machine reversal, haul road design, human fault, operator's fault, machine fault, visibility and dump design. Considering the types of machines, namely, dumpers, excavators, dozers and loaders together the maximum number of fatal accidents has been caused by operator's faults and human faults jointly during the period from 1995 to 2008. The novel finding of this analysis is that large machines with state-of-the-art safety system did not reduce the fatal accidents in Indian opencast coal mines.
Excavating and loading equipment for peat mining
NASA Astrophysics Data System (ADS)
Mikhailov, A. V.; Zhigulskaya, A. I.; Yakonovskaya, T. B.
2017-10-01
Recently, the issues of sustainable development of Russian regions, related to ensuring energy security, are more urgent than ever. To achieve sustainable development, an integrated approach to the use of local natural resources is needed. Practically in all north regions of the Russian Federation, peat as a local natural resource is widespread, which has a practical application in the area of housing services. The paper presents the evaluation of technologies for open-pit peat mining, as well as analysis of technological equipment for peat production. Special attention is paid to a question of peat materials excavating and loading. The problem of equipment selection in a peat surface mine is complex. Many features, restrictions and criteria need to be considered. Use of low and ultra-low ground pressure excavators and low ground pressure front-end loaders with full-range tires to provide the necessary floatation in the peat bog environment is offered.
Jo, Chang Hwa; Kim, Junsoo; Han, Ah-reum; Park, Sam Yong; Hwang, Kwang Yeon; Nam, Ki Hyun
2016-03-01
Site-specific Xer recombination plays a pivotal role in reshuffling genetic information. Here, we report the 2.5 Å crystal structure of XerA from the archaean Thermoplasma acidophilum. Crystallographic data reveal a uniquely open conformational state, resulting in a C-shaped clamp with an angle of ~ 48° and a distance of 57 Å between the core-binding and the catalytic domains. The catalytic nucleophile, Tyr264, is positioned in cis-cleavage mode by XerA's C-term tail that interacts with the CAT domain of a neighboring monomer without DNA substrate. Structural comparisons of tyrosine recombinases elucidate the dynamics of Xer recombinase. © 2016 Federation of European Biochemical Societies.
Ferrari Engines, Bicycle Brakes
ERIC Educational Resources Information Center
Hallowell, Edward
2012-01-01
In this article, the author offers an advice to educators about how to help students with attention deficit hyperactivity disorder (ADHD) fulfill the potential of their powerful brains. It is a neurological fact that feeling safe opens up the brain, whereas feeling anxious and afraid clamps it down. So step one is to make sure all students feel as…
Breneman, Kathryn D; Highstein, Stephen M; Boyle, Richard D; Rabbitt, Richard D
2009-01-01
Somatic measurements of whole-cell capacitance are routinely used to understand physiologic events occurring in remote portions of cells. These studies often assume the intracellular space is voltage-clamped. We questioned this assumption in auditory and vestibular hair cells with respect to their stereocilia based on earlier studies showing that neurons, with radial dimensions similar to stereocilia, are not always isopotential under voltage-clamp. To explore this, we modeled the stereocilia as passive cables with transduction channels located at their tips. We found that the input capacitance measured at the soma changes when the transduction channels at the tips of the stereocilia are open compared to when the channels are closed. The maximum capacitance is felt with the transducer closed but will decrease as the transducer opens due to a length-dependent voltage drop along the stereocilium length. This potential drop is proportional to the intracellular resistance and stereocilium tip conductance and can produce a maximum capacitance error on the order of fF for single stereocilia and pF for the bundle.
Properties of Single K+ and Cl− Channels in Asclepias tuberosa Protoplasts 1
Schauf, Charles L.; Wilson, Kathryn J.
1987-01-01
Potassium and chloride channels were characterized in Asclepias tuberosa suspension cell derived protoplasts by patch voltage-clamp. Whole-cell currents and single channels in excised patches had linear instantaneous current-voltage relations, reversing at the Nernst potentials for K+ and Cl−, respectively. Whole cell K+ currents activated exponentially during step depolarizations, while voltage-dependent Cl− channels were activated by hyperpolarizations. Single K+ channel conductance was 40 ± 5 pS with a mean open time of 4.5 milliseconds at 100 millivolts. Potassium channels were blocked by Cs+ and tetraethylammonium, but were insensitive to 4-aminopyridine. Chloride channels had a single-channel conductance of 100 ± 17 picosiemens, mean open time of 8.8 milliseconds, and were blocked by Zn2+ and ethacrynic acid. Whole-cell Cl− currents were inhibited by abscisic acid, and were unaffected by indole-3-acetic acid and 2,4-dichlorophenoxyacetic acid. Since internal and external composition can be controlled, patch-clamped protoplasts are ideal systems for studying the role of ion channels in plant physiology and development. Images Fig. 5 PMID:16665712
Brinkmann, Saskia J H; Buijs, Nikki; Vermeulen, Mechteld A R; Oosterink, Efraim; Schierbeek, Henk; Beishuizen, Albertus; de Vries, Jean-Paul P M; Wisselink, Willem; van Leeuwen, Paul A M
2016-09-01
Postoperative renal failure is a common complication after open repair of an abdominal aortic aneurysm. The amino acid arginine is formed in the kidneys from its precursor citrulline, and citrulline is formed from glutamine in the intestines. Arginine enhances the function of the immune and cardiovascular systems, which is important for recovery after surgery. We hypothesized that renal arginine production is diminished after ischemia-reperfusion injury caused by clamping of the aorta during open abdominal aortic surgery and that parenteral glutamine supplementation might compensate for this impaired arginine synthesis. This open-label clinical trial randomized patients who underwent clamping of the aorta during open abdominal aortic surgery to receive a perioperative supplement of intravenous alanyl-glutamine (0.5 g·kg(-1)·day(-1); group A, n = 5) or no supplement (group B, n = 5). One day after surgery, stable isotopes and tracer methods were used to analyze the metabolism and conversion of glutamine, citrulline, and arginine. Whole body plasma flux of glutamine, citrulline, and arginine was significantly higher in group A than in group B (glutamine: 391 ± 34 vs. 258 ± 19 μmol·kg(-1)·h(-1), citrulline: 5.7 ± 0.4 vs. 2.8 ± 0.4 μmol·kg(-1)·h(-1), and arginine: 50 ± 4 vs. 26 ± 2 μmol·kg(-1)·h(-1), P < 0.01), as was the synthesis of citrulline from glutamine (4.8 ± 0.7 vs. 1.6 ± 0.3 μmol·kg(-1)·h(-1)), citrulline from arginine (2.3 ± 0.3 vs. 0.96 ± 0.1 μmol·kg(-1)·h(-1)), and arginine from glutamine (7.7 ± 0.4 vs. 2.8 ± 0.2 μmol·kg(-1)·h(-1)), respectively (P < 0.001 for all). In conclusion, the production of citrulline and arginine is severely reduced after clamping during aortic surgery. This study shows that an intravenous supplement of glutamine increases the production of citrulline and arginine and compensates for the inhibitory effect of ischemia-reperfusion injury. Copyright © 2016 the American Physiological Society.
Flying-patch patch-clamp study of G22E-MscL mutant under high hydrostatic pressure.
Petrov, Evgeny; Rohde, Paul R; Martinac, Boris
2011-04-06
High hydrostatic pressure (HHP) present in natural environments impacts on cell membrane biophysical properties and protein quaternary structure. We have investigated the effect of high hydrostatic pressure on G22E-MscL, a spontaneously opening mutant of Escherichia coli MscL, the bacterial mechanosensitive channel of large conductance. Patch-clamp technique combined with a flying-patch device and hydraulic setup allowed the study of the effects of HHP up to 90 MPa (as near the bottom of the Marianas Trench) on the MscL mutant channel reconstituted into liposome membranes, in addition to recording in situ from the mutant channels expressed in E. coli giant spheroplasts. In general, against thermodynamic predictions, hydrostatic pressure in the range of 0.1-90 MPa increased channel open probability by favoring the open state of the channel. Furthermore, hydrostatic pressure affected the channel kinetics, as manifested by the propensity of the channel to gate at subconducting levels with an increase in pressure. We propose that the presence of water molecules around the hydrophobic gate of the G22E MscL channel induce hydration of the hydrophobic lock under HHP causing frequent channel openings and preventing the channel closure in the absence of membrane tension. Furthermore, our study indicates that HHP can be used as a valuable experimental approach toward better understanding of the gating mechanism in complex channels such as MscL. Copyright © 2011 Biophysical Society. Published by Elsevier Inc. All rights reserved.
Time to aortic occlusion: It's all about access.
Romagnoli, Anna; Teeter, William; Pasley, Jason; Hu, Peter; Hoehn, Melanie; Stein, Deborah; Scalea, Thomas; Brenner, Megan
2017-12-01
Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a less invasive method of proximal aortic occlusion compared with resuscitative thoracotomy with aortic cross-clamping (RTACC). This study compared time to aortic occlusion with REBOA and RTACC, both including and excluding time required for common femoral artery (CFA) cannulation. This was a retrospective, single-institution review of REBOA or RTACC performed between February 2013 and January 2016. Time of skin incision to aortic cross-clamp for RTACC, time required for CFA cannulation by percutaneous and open methods, and time from guide-wire insertion to balloon inflation at Zone 1 for REBOA, were obtained from videographic recordings. Eighteen RTACC and 21 REBOAs were performed. Median (Q1, Q3) time from skin incision to aortic cross-clamping was 317 seconds (227, 551 seconds). Median (Q1, Q3) time from start of arterial access to Zone 1 balloon occlusion was 474 seconds (431, 572 seconds) (vs. RTACC, p = 0.01). All REBOA procedures were performed with the same device. The median time to complete CFA cannulation was 247 seconds (range, 164-343 seconds), with no difference between percutaneous or open procedures (p = 0.07). The median (Q1, Q3) time to aortic occlusion in REBOA once arterial access had been established was 245 seconds (179, 295.5 seconds), which was significantly shorter than RTACC (p = 0.003). Once CFA access is achieved, time to aortic occlusion is faster with REBOA. Time to aortic occlusion is less than the time required to cannulate the CFA either by percutaneous or open approaches, emphasizing the importance of accurate and expedient CFA access. Resuscitative endovascular balloon occlusion of the aorta may represent a feasible alternative to thoracotomy for aortic occlusion. Time to aortic occlusion will likely decrease with the advent of newer REBOA technology. The rate-limiting portion of REBOA continues to be obtaining CFA access. Therapeutic, level V.
Pottecher, Julien; Guillot, Max; Belaidi, Elise; Charles, Anne-Laure; Lejay, Anne; Gharib, Abdallah; Diemunsch, Pierre; Geny, Bernard
2013-04-01
By binding to cyclophilin D, cyclosporine A (CsA) inhibits mitochondrial permeability transition pore (mPTP) opening and prevents mitochondrial dysfunction and ultimately cell death after ischemia-reperfusion (IR) injury in cardiac muscle. This study tested whether CsA would decrease skeletal muscle oxidative stress and mitochondrial dysfunctions after aortic cross-clamping related IR. Forty-five Wistar rats were investigated. The sham group (n = 8) had aortic exposure but no ischemia, the IR group (n = 10) had aortic cross-clamping for 3 hours followed by 2 hours of reperfusion, and the IR+CsA group (n = 9) had two intraperitoneal injections of 10 mg of CsA at 90 and 150 minutes of ischemia before reperfusion. Mitochondrial coupling (acceptor control ratio) and mitochondrial respiratory chain complexes' activities were measured. Reactive oxygen species (ROS) production, cyclophilin D expression, and muscle inflammation were determined using dihydroethidium staining, Western blot, and immunohistochemistry, respectively. An additional 18 sham rats were investigated to determine CsA blood levels and the effects of CsA on mitochondrial respiration and calcium retention capacity, a marker of mPTP opening, both in myocardium and gastrocnemius with and without CsA. Compared with sham, IR decreased mitochondrial coupling (1.38 ± 0.06 vs 1.98 ± 0.20; P = .0092), increased ROS production (3992 ± 706 arbitrary units [AU] vs 1812 ± 322 AU; P = .033), was associated with macrophage infiltration, and decreased maximal oxidative capacity (V(max): 4.08 ± 0.38 μmol O(2)/min/g vs 5.98 ± 0.56 μmol O(2)/min/g; P = .015). Despite IR, CsA treatment totally restored mitochondrial coupling (1.93 ± 0.12; P = .023 vs IR), normalized ROS (1569 ± 348 AU; P = .0098 vs IR), and decreased inflammation. The V(max) was slightly enhanced (5.02 ± 0.39 μmol O(2)/min/g; P = .33 vs IR; P = .35 vs sham). Compared with myocardium, gastrocnemius muscle was characterized by a decreased cyclophilin D content (-50%) associated with an earlier opening of mPTP (calcium retention capacity increased from 10.85 ± 1.35 μM/mg dry weight [DW] to 12.11 ± 2.77 μM/mg DW; P = .65; and from 11.07 ± 1.67 to 37.65 ± 11.41 μM/mg DW; P = .0098 in gastrocnemius and heart, respectively). Cyclosporine A normalized ROS production, decreased inflammation, and restored mitochondrial coupling during aortic cross-clamping. Incomplete Vmax protection might be due to low cyclophilin D expression in gastrocnemius, preventing CsA from blocking mPTP opening. Copyright © 2013 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.
Sammoura, Firas; Smyth, Katherine; Kim, Sang-Gook
2013-09-01
An electric circuit model for a clamped circular bimorph piezoelectric micromachined ultrasonic transducer (pMUT) was developed for the first time. The pMUT consisted of two piezoelectric layers sandwiched between three thin electrodes. The top and bottom electrodes were separated into central and annular electrodes by a small gap. While the middle electrode was grounded, the central and annular electrodes were biased with two independent voltage sources. The strain mismatch between the piezoelectric layers caused the plate to vibrate and transmit a pressure wave, whereas the received echo generated electric charges resulting from plate deformation. The clamped pMUT plate was separated into a circular and an annular plate, and the respective electromechanical transformation matrices were derived. The force and velocity vectors were properly selected using Hamilton's principle and the necessary boundary conditions were invoked. The electromechanical transformation matrix for the clamped circular pMUT was deduced using simple matrix manipulation techniques. The pMUT performance under three biasing schemes was elaborated: 1) central electrode only, 2) central and annular electrodes with voltages of the same magnitude and polarity, and 3) central and annular electrodes with voltages of the same magnitude and opposite polarity. The circuit parameters of the pMUT were extracted for each biasing scheme, including the transformer ratio, the clamped electric impedance, and the open-circuit mechanical impedance. Each pMUT scheme was characterized under different acoustic loadings using the theoretically developed model, which was verified with finite element modeling (FEM) simulation. The electrode size was optimized to maximize the electromechanical transformer ratio. As such, the developed model could provide more insight into the design, optimization, and characterization of pMUTs and allow for performance comparison with their cMUT counterparts.
Kim, Ki-Young; Lee, Jung-Ju
2012-12-01
As there is a shortage of scrub nurses in many hospitals, automatic surgical tool exchanging mechanism without human labour has been studied. Minimally invasive robotic surgeries (MIRS) also require scrub nurses. A surgical tool loading mechanism without a scrub nurse's assistance for MIRS is proposed. Many researchers have developed minimally invasive surgical instruments with a wrist joint that can be movable inside the abdomen. However, implementation of a distal rolling joint on a gripper is rare. To implement surgical tool exchanging without a scrub nurse's assistance, a slave manipulator and a tool loader were developed to load and unload a surgical tool unit. A surgical tool unit with a roll-pitch-roll wrist was developed. Several experiments were performed to validate the effectiveness of the slave manipulator and the surgical tool unit. The slave manipulator and the tool loader were able to successfully unload and load the surgical tool unit without human assistance. The total duration of unloading and loading the surgical tool unit was 97 s. Motion tracking experiments of the distal rolling joint were performed. The maximum positioning error of the step input response was 2°. The advantage of the proposed slave manipulator and tool loader is that other robotic systems or human labour are not needed for surgical tool loading. The feasibility of the distal rolling joint in MIS is verified. Copyright © 2012 John Wiley & Sons, Ltd.
NASA Technical Reports Server (NTRS)
Girala, A. S. (Inventor)
1981-01-01
A self clamping cutting tool which includes a handle attached to a C-shaped housing is described. Rotatably mounted within the housing is a C-shaped tool body carrying a set of clamping rolls, two support rolls, and an edged cutting roll (64). The support rolls are disposed to one side of the axis of a pipe and the cutting roll is disposed to the other side of a pipe axis so that these rolls contact a pipe at three circumferential points. Cutter advancing apparatus advance the cutting roll toward the support rollers. The support rolls and cutting roll are rotatable independently of the C-shaped housing. A one way ratchet mechanism disposed between the C-shaped housing and the C-shaped tool body permits operation by movement in one rotational direction about the pipe axis.
Integrated multiple patch-clamp array chip via lateral cell trapping junctions
NASA Astrophysics Data System (ADS)
Seo, J.; Ionescu-Zanetti, C.; Diamond, J.; Lal, R.; Lee, L. P.
2004-03-01
We present an integrated multiple patch-clamp array chip by utilizing lateral cell trapping junctions. The intersectional design of a microfluidic network provides multiple cell addressing and manipulation sites for efficient electrophysiological measurements at a number of patch sites. The patch pores consist of openings in the sidewall of a main fluidic channel, and a membrane patch is drawn into a smaller horizontal channel. This device geometry not only minimizes capacitive coupling between the cell reservoir and the patch channel, but also allows simultaneous optical and electrical measurements of ion channel proteins. Evidence of the hydrodynamic placement of mammalian cells at the patch sites as well as measurements of patch sealing resistance is presented. Device fabrication is based on micromolding of polydimethylsiloxane, thus allowing inexpensive mass production of disposable high-throughput biochips.
1. MAGAZINE COMPLEX, O, P, AND Q. MAGAZINE P IN ...
1. MAGAZINE COMPLEX, O, P, AND Q. MAGAZINE P IN BACKGROUND, LOOKING NORTHEAST. - NIKE Missile Base C-84, Underground Storage Magazines & Launcher-Loader Assemblies, Easternmost portion of launch area, Barrington, Cook County, IL
Laparoscopic partial nephrectomy for renal tumor: Nagoya experience.
Yoshikawa, Yoko; Ono, Yoshinari; Hattori, Ryohei; Gotoh, Momokazu; Yoshino, Yasushi; Katsuno, Satoshi; Katoh, Masashi; Ohshima, Shinichi
2004-08-01
To clarify the indication for a vascular clamp during laparoscopic partial nephrectomy, the clinical results of 17 patients who underwent the procedure for small renal tumors were reviewed. Seventeen patients with renal tumors were enrolled in our laparoscopic partial nephrectomy program between October 1999 and November 2003. During laparoscopy, a vascular clamp was used to remove the tumor mass and suture the incised renal parenchyma and urinary collecting system in 8 patients who had less-than-1-cm-thick renal parenchyma between the mass and the renal sinus or calices. In the remaining 9 patients, who had 1-cm-or-more-thick renal parenchyma between the mass and sinus or calices, renal bleeding was controlled using ultrasonic scissors, gauze tampon, argon beam coagulator, and fibrin glue. Sixteen patients were successfully treated with laparoscopy; one required conversion to open surgery because of uncontrollable bleeding. The average operative time was 4.5 hours, and average estimated bleeding volume was 301 mL. In the 8 patients requiring vascular clamping by forceps, the average ischemic time was 25 minutes. In all patients, the tumor mass was completely removed with negative surgical margins, and renal function was preserved. Three patients had prolonged urinary leakage for a mean of 21 days. Laparoscopic partial nephrectomy offers many advantages, including surgery that is both nephron sparing and minimally invasive. A vascular clamp was indicated for patients with less-than-1-cm-thick renal parenchyma between the tumor mass and renal sinus or calices.
Code of Federal Regulations, 2013 CFR
2013-07-01
... of Steel Products (available at each Regional Office of the Occupational Safety and Health... Society of Automotive Engineers Recommended Practices: SAE J320a, Minimum Performance Criteria for Roll...
Code of Federal Regulations, 2014 CFR
2014-07-01
... of Steel Products (available at each Regional Office of the Occupational Safety and Health... Society of Automotive Engineers Recommended Practices: SAE J320a, Minimum Performance Criteria for Roll...
Code of Federal Regulations, 2010 CFR
2010-07-01
... of Steel Products (available at each Regional Office of the Occupational Safety and Health... Society of Automotive Engineers Recommended Practices: SAE J320a, Minimum Performance Criteria for Roll...
Code of Federal Regulations, 2011 CFR
2011-07-01
... of Steel Products (available at each Regional Office of the Occupational Safety and Health... Society of Automotive Engineers Recommended Practices: SAE J320a, Minimum Performance Criteria for Roll...
Code of Federal Regulations, 2012 CFR
2012-07-01
... of Steel Products (available at each Regional Office of the Occupational Safety and Health... Society of Automotive Engineers Recommended Practices: SAE J320a, Minimum Performance Criteria for Roll...
Cognitive simulation of incident risks in the structure of loading and transport enterprise
NASA Astrophysics Data System (ADS)
Shishkina, S. V.; Pristupa, Yu D.; Pavlova, L. D.; Fryanov, V. N.
2017-09-01
Organizational and technical system of a manufacturing enterprise was identified, which includes three subsystems: main production, industrial and social infrastructure. Based on the results of cognitive modeling, significant system concepts were identified that reduce the risks of incidents. The internal control influences formed in accordance with level of competence of heads of services, departments, sections, dispatchers, acting on the basis of regulations, job profiles. The second concept influencing the enterprise management system is personnel, which is assessed by the compliance of competencies of crane operators, loader operators, slingers, loaders, and acceptance/delivery agents to job responsibilities and labor functions. At a low level of professional competencies, the personnel does not fully comply with job duties and labor functions, the risk of an incident is maximal. The application of cognitive modeling allows us to identify the essential elements that ensure stable functioning of the system as a whole.
In-line drivetrain and four wheel drive work machine using same
Hoff, Brian
2008-08-05
A four wheel drive articulated mine loader is powered by a fuel cell and propelled by a single electric motor. The drivetrain has the first axle, second axle, and motor arranged in series on the work machine chassis. Torque is carried from the electric motor to the back differential via a pinion meshed with the ring gear of the back differential. A second pinion oriented in an opposite direction away from the ring gear is coupled to a drive shaft to transfer torque from the ring gear to the differential of the front axle. Thus, the ring gear of the back differential acts both to receive torque from the motor and to transfer torque to the forward axle. The in-line drive configuration includes a single electric motor and a single reduction gear to power the four wheel drive mine loader.
NASA Astrophysics Data System (ADS)
Aufdenkampe, A. K.; Mayorga, E.; Horsburgh, J. S.; Lehnert, K. A.; Zaslavsky, I.
2015-12-01
We have developed a family of solutions to the challenges of integrating diverse data from of biological and geological (BiG) disciplines for Critical Zone (CZ) science. These standards and software solutions have been developed around the new Observations Data Model version 2.0 (ODM2, http://ODM2.org), which was designed as a profile of the Open Geospatial Consortium's (OGC) Observations and Measurements (O&M) standard. The ODM2 standards and software ecosystem has at it's core an information model that balances specificity with flexibility to powerfully and equally serve the needs of multiple dataset types, from multivariate sensor-generated time series to geochemical measurements of specimen hierarchies to multi-dimensional spectral data to biodiversity observations. ODM2 has been adopted as the information model guiding the next generation of cyberinfrastructure development for the Interdisciplinary Earth Data Alliance (http://www.iedadata.org/) and the CUAHSI Water Data Center (https://www.cuahsi.org/wdc). Here we present several components of the ODM2 standards and software ecosystem that were developed specifically to help CZ scientists and their data managers to share and manage data through the national Critical Zone Observatory data integration project (CZOData, http://criticalzone.org/national/data/) and the bio integration with geo for critical zone science data project (BiG CZ Data, http://bigcz.org/). These include the ODM2 Controlled Vocabulary system (http://vocabulary.odm2.org), the YAML Observation Data Archive & exchange (YODA) File Format (https://github.com/ODM2/YODA-File) and the BiG CZ Toolbox, which will combine easy-to-install ODM2 databases (https://github.com/ODM2/ODM2) with a variety of graphical software packages for data management such as ODMTools (https://github.com/ODM2/ODMToolsPython) and the ODM2 Streaming Data Loader (https://github.com/ODM2/ODM2StreamingDataLoader).
Residual right portal branch flow after first-step ALPPS: artifact or homeostatic response?
De Carlis, Luciano; Sguinzi, Raffaella; De Carlis, Riccardo; Di Sandro, Stefano; Mangoni, Jacopo; Aseni, Paolo; Giacomoni, Alessandro; Vanzulli, Angelo
2014-09-01
Mutual interactions between portal vein and hepatic artery can be documented during hepatobiliary surgery. Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy (ALPPS) is a recently introduced surgical technique which can also represent a unique living human model to investigate intrahepatic blood circulation. We report three consecutive cases in which a residual right portal branch flow was clearly detectable after first-step ALPPS, and try to further investigate this unexpected finding with intraoperative clamping tests. Every patient was evaluated with CT scan 7 days after first-step ALPPS and Intraoperative Doppler Ultrasonography (IOUS) at both steps of the procedure. In every patient, CT scan and second-step IOUS demonstrated a clear hepatopetal flow distally to the divided right portal branch. The flow was present after right biliary duct clamping and stopped after right total hilar clamping as well as after right hepatic artery occlusion. Neither cross-portal circulation between the two hemilivers nor trans-sinusoidal backflow from the hepatic veins can explain these findings, which are rather consistent with a refilling of the occluded portal branch through the opening of intrahepatic arterioportal shunts (APS). APS could represent the simplest homeostatic mechanism that regulate intrahepatic blood flow.
Is early cord clamping, delayed cord clamping or cord milking best?
Vatansever, Binay; Demirel, Gamze; Ciler Eren, Elif; Erel, Ozcan; Neselioglu, Salim; Karavar, Hande Nur; Gundogdu, Semra; Ulfer, Gozde; Bahadir, Selcen; Tastekin, Ayhan
2018-04-01
To compare the antioxidant status of three cord clamping procedures (early clamping, delayed clamping and milking) by analyzing the thiol-disulfide balance. This randomized controlled study enrolled 189 term infants who were divided into three groups according to the cord clamping procedure: early clamping, delayed clamping and milking. Blood samples were collected from the umbilical arteries immediately after clamping, and the thiol/disulfide homeostasis was analyzed. The native and total thiol levels were significantly (p < .05) lower in the early cord clamping group compared with the other two groups. The disulfide/total thiol ratio was significantly (p = .026) lower in the delayed cord clamping and milking groups compared with the early clamping groups. Early cord clamping causes the production of more disulfide bonds and lower thiol levels, indicating that oxidation reactions are increased in the early cord clamping procedure compared with the delayed cord clamping and milking procedures. The oxidant capacity is greater with early cord clamping than with delayed clamping or cord milking. Delayed cord clamping or milking are beneficial in neonatal care, and we suggest that they be performed routinely in all deliveries.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dokos, J.A.
1996-12-31
A drill bit loader is described for loading a tapered shank of a drill bit into a similarly tapered recess in the end of a drill spindle. The spindle has a transverse slot at the inner end of the recess. The end of the tapered shank of the drill bit has a transverse tang adapted to engage in the slot so that the drill bit will be rotated by the spindle. The loader is in the form of a cylinder adapted to receive the drill bit with the shank projecting out of the outer end of the cylinder. Retainer pinsmore » prevent rotation of the drill bit in the cylinder. The spindle is lowered to extend the shank of the drill bit into the recess in the spindle and the spindle is rotated to align the slot in the spindle with the tang on the shank. A spring unit in the cylinder is compressed by the drill bit during its entry into the recess of the spindle and resiliently drives the tang into the slot in the spindle when the tang and slot are aligned. In typical remote drilling operations, whether in hot cells or water pits, drill bits have been held using a collet or end mill type holder with set screws. In either case, to load or change a drill bit required the use master-slave manipulators to position the bits and tighten the collet or set screws. This requirement eliminated many otherwise useful work areas because they were not equipped with slaves, particularly in water pits.« less
Melatonin mediates vasodilation through both direct and indirect activation of BKCa channels.
Zhao, T; Zhang, H; Jin, C; Qiu, F; Wu, Y; Shi, L
2017-10-01
Melatonin, synthesized primarily by the pineal gland, is a neuroendocrine hormone with high membrane permeability. The vascular effects of melatonin, including vasoconstriction and vasodilation, have been demonstrated in numerous studies. However, the mechanisms underlying these effects are not fully understood. Large-conductance Ca 2+ -activated K + (BK Ca ) channels are expressed broadly on smooth muscle cells and play an important role in vascular tone regulation. This study explored the mechanisms of myocyte BK Ca channels and endothelial factors underlying the action of melatonin on the mesenteric arteries (MAs). Vascular contractility and patch-clamp studies were performed on myocytes of MAs from Wistar rats. Melatonin induced significant vasodilation on MAs. In the presence of N ω -nitro-l-arginine methyl ester (l-NAME), a potent endothelial oxide synthase (eNOS) inhibitor, melatonin elicited concentration-dependent relaxation, with lowered pIC 50 The effect of melatonin was significantly attenuated in the presence of BK Ca channel blocker iberiotoxin or MT1/MT2 receptor antagonist luzindole in both (+) l-NAME and (-) l-NAME groups. In the (+) l-NAME group, iberiotoxin caused a parallel rightward shift of the melatonin concentration-relaxation curve, with pIC 50 lower than that of luzindole. Both inside-out and cell-attached patch-clamp recordings showed that melatonin significantly increased the open probability, mean open time and voltage sensitivity of BK Ca channels. In a cell-attached patch-clamp configuration, the melatonin-induced enhancement of BK Ca channel activity was significantly suppressed by luzindole. These findings indicate that in addition to the activation of eNOS, melatonin-induced vasorelaxation of MAs is partially attributable to its direct (passing through the cell membrane) and indirect (via MT1/MT2 receptors) activation of the BK Ca channels on mesenteric arterial myocytes. © 2017 Society for Endocrinology.
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PRN 2009-1: Establishment of Antimicrobial Exposure Assessment Task Force II
This PR notice announces the establishment of the Antimicrobial Exposure Assessment Task Force II, an industry-wide task force to develop mixer, loader, applicator and post-application exposure data for antimicrobial pesticides used in various settings.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Definitions. 158.3 Section 158.3 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRPORTS... airport to support aeronautical operations and related activities. Baggage tugs, belt loaders, cargo...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Definitions. 158.3 Section 158.3 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRPORTS... airport to support aeronautical operations and related activities. Baggage tugs, belt loaders, cargo...
High current capacity electrical connector
Bettis, Edward S.; Watts, Harry L.
1976-01-13
An electrical connector is provided for coupling high current capacity electrical conductors such as copper busses or the like. The connector is arranged in a "sandwiched" configuration in which a conductor plate contacts the busses along major surfaces thereof clamped between two stainless steel backing plates. The conductor plate is provided with a plurality of contact buttons affixed therein in a spaced array such that the caps of the buttons extend above the conductor plate surface to contact the busses. When clamping bolts provided through openings in the sandwiched arrangement are tightened, Belleville springs provided under the rim of each button cap are compressed and resiliently force the caps into contact with the busses' contacting surfaces to maintain a predetermined electrical contact area provided by the button cap tops. The contact area does not change with changing thermal or mechanical stresses applied to the coupled conductors.
PRN 2007-3: The Agricultural Handlers Exposure Task Force, L.L.C
This PR Notice discusses the Agricultural Handlers Exposure Task Force, an industry-wide task force formed to develop mixer, loader, and applicator exposure data for pesticides used in agricultural settings. It includes contacts for more information.
Xu, Shi-Zhou; Wang, Chun-Jie; Lin, Fang-Li; Li, Shi-Xiang
2017-10-31
The multi-device open-circuit fault is a common fault of ANPC (Active Neutral-Point Clamped) three-level inverter and effect the operation stability of the whole system. To improve the operation stability, this paper summarized the main solutions currently firstly and analyzed all the possible states of multi-device open-circuit fault. Secondly, an order-reduction optimal control strategy was proposed under multi-device open-circuit fault to realize fault-tolerant control based on the topology and control requirement of ANPC three-level inverter and operation stability. This control strategy can solve the faults with different operation states, and can works in order-reduction state under specific open-circuit faults with specific combined devices, which sacrifices the control quality to obtain the stability priority control. Finally, the simulation and experiment proved the effectiveness of the proposed strategy.
AstroML: Python-powered Machine Learning for Astronomy
NASA Astrophysics Data System (ADS)
Vander Plas, Jake; Connolly, A. J.; Ivezic, Z.
2014-01-01
As astronomical data sets grow in size and complexity, automated machine learning and data mining methods are becoming an increasingly fundamental component of research in the field. The astroML project (http://astroML.org) provides a common repository for practical examples of the data mining and machine learning tools used and developed by astronomical researchers, written in Python. The astroML module contains a host of general-purpose data analysis and machine learning routines, loaders for openly-available astronomical datasets, and fast implementations of specific computational methods often used in astronomy and astrophysics. The associated website features hundreds of examples of these routines being used for analysis of real astronomical datasets, while the associated textbook provides a curriculum resource for graduate-level courses focusing on practical statistics, machine learning, and data mining approaches within Astronomical research. This poster will highlight several of the more powerful and unique examples of analysis performed with astroML, all of which can be reproduced in their entirety on any computer with the proper packages installed.
McArthur removes AAA clamps and ducts inside the CHeCS Rack during Expedition 12
2005-12-09
ISS012-E-10817 (9 December 2005) --- Astronaut William S. (Bill) McArthur Jr., Expedition 12 commander and NASA space station science officer, opens the back panel of the Crew Health Care System (CHeCS) rack and removes the Avionics Air Assembly (AAA) air ducts during in-flight maintenance (IFM) in the Destiny laboratory of the International Space Station.
Triple bar, high efficiency mechanical sealer
Pak, Donald J.; Hawkins, Samantha A.; Young, John E.
2013-03-19
A clamp with a bottom clamp bar that has a planar upper surface is provided. The clamp may also include a top clamp bar connected to the bottom clamp bar, and a pressure distribution bar between the top clamp bar and the bottom clamp bar. The pressure distribution bar may have a planar lower surface in facing relation to the upper surface of the bottom clamp bar. An object is capable of being disposed in a clamping region between the upper surface and the lower surface. The width of the planar lower surface may be less than the width of the upper surface within the clamping region. Also, the pressure distribution bar may be capable of being urged away from the top clamp bar and towards the bottom clamp bar.
Pemp, Berthold; Polska, Elzbieta; Garhofer, Gerhard; Bayerle-Eder, Michaela; Kautzky-Willer, Alexandra; Schmetterer, Leopold
2010-09-01
To compare total retinal blood flow in diabetic patients with no or mild nonproliferative diabetic retinopathy and healthy control subjects and to investigate in patients whether there is a difference between retinal blood flow before morning insulin and under normoglycemic conditions using a glucose clamp. Twenty patients with type 1 diabetes with no or mild diabetic retinopathy were included in this open parallel-group study, and 20 healthy age- and sex-matched subjects were included as control subjects. Retinal blood flow was assessed by combining velocity measurements using laser Doppler velocimetry and diameter measurements using a commercially available dynamic vessel analyzer. Measurements were performed before and during a euglycemic clamp. Total retinal blood flow was higher in diabetic patients (53 +/- 16 microl/min) than in healthy subjects (43 +/- 16 microl/min; P = 0.034 between groups). When plasma glucose in diabetic patients was reduced from 9.3 +/- 1.7 to 5.3 +/- 0.5 mmol/l (P < 0.001) retinal blood flow decreased to 49 +/- 15 microl/min (P = 0.0003 vs. baseline). Total retinal blood flow during the glucose clamp was not significantly different from blood flow in normal control subjects (P = 0.161). Type 1 diabetic patients with no or only mild diabetic retinopathy have increased retinal blood flow before their morning insulin dosage. Blood flow is reduced toward normal during euglycemic conditions. Retinal blood flow may fluctuate significantly with fluctuating plasma glucose levels, which may contribute to the microvascular changes seen in diabetic retinopathy.
NASA Technical Reports Server (NTRS)
Ramsey, John K. (Inventor); Meyn, Erwin H. (Inventor)
1990-01-01
A pair of spaced collars are mounted at right angles on a clamp body by retaining rings which enable the collars to rotate with respect to the clamp body. Mounting posts extend through aligned holes in the collars and clamp body. Each collar can be clamped onto the inserted post while the clamp body remains free to rotate about the post and collar. The clamp body is selectively clamped onto each post.
Terrain - Umbra Package v. 1.0
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oppel, Fred; Hart, Brian; Rigdon, James Brian
This library contains modules that read terrain files (e.g., OpenFlight, Open Scene Graph IVE, GeoTIFF Image) and to read and manage ESRI terrain datasets. All data is stored and managed in Open Scene Graph (OSG). Terrain system accesses OSG and provides elevation data, access to meta-data such as soil types and enables linears, areals and buildings to be placed in a terrain, These geometry objects include boxes, point, path, and polygon (region), and sector modules. Utilities have been made available for clamping objects to the terrain and accessing LOS information. This assertion includes a managed C++ wrapper code (TerrainWrapper) tomore » enable C# applications, such as OpShed and UTU, to incorporate this library.« less
Characteristics of single Ca(2+) channel kinetics in feline hypertrophied ventricular myocytes.
Yang, Xiangjun; Hui, Jie; Jiang, Tingbo; Song, Jianping; Liu, Zhihua; Jiang, Wenping
2002-04-01
To explore the mechanism underlying the prolongation of action potential and delayed inactivation of the L-type Ca(2+) (I(Ca, L)) current in a feline model of left ventricular system hypertension and concomitant hypertrophy. Single Ca(2+) channel properties in myocytes isolated from normal and pressure overloaded cat left ventricles were studied, using patch-clamp techniques. Left ventricular pressure overload was induced by partial ligation of the ascending aorta for 4 - 6 weeks. The amplitude of single Ca(2+) channel current evoked by depolarizing pulses from -40 mV to 0 mV was 1.02 +/- 0.03 pA in normal cells and 1.05 +/- 0.03 pA in hypertrophied cells, and there was no difference in single channel current-voltage relationships between the groups since slope conductance was 26.2 +/- 1.0 pS in normal and hypertrophied cells, respectively. Peak amplitudes of the ensemble-averaged single Ca(2+) channel currents were not different between the two groups of cells. However, the amplitude of this averaged current at the end of the clamp pulse was significantly larger in hypertrophied cells than in normal cells. Open-time histograms revealed that open-time distribution was fitted by a single exponential function in channels of normal cells and by a two exponential function in channels of hypertrophied cells. The number of long-lasting openings was increased in channels of hypertrophied cells, and therefore the calculated mean open time of the channel was significantly longer compared to normal controls. Kinetic changes in the Ca(2+) channel may underlie both hypertrophy-associated delayed inactivation of the Ca(2+) current and, in part, the pressure overload-induced action potential lengthening in this cat model of ventricular left systolic hypertension and hypertrophy.
Kulshrestha, Vikas
2008-01-01
Background: A major drawback of conventional fixator system is the penetration of fixator pins into the medullary canal. The pins create a direct link between the medullary cavity and outer environment, leading to higher infection rates on conversion to intramedullary nailing. This disadvantage is overcome by the AO pinless fixator, in which the trocar points are clamped onto the outer cortex without penetrating it. This study was designed to evaluate the role of AO pinless fixators in primary stabilization of open diaphyseal tibial fractures that received staged treatment because of delayed presentation or poor general condition. We also analyzed the rate of infection on early conversion to intramedullary nail. Materials and Methods: This study is a retrospective review of 30 open diaphyseal fractures of tibia, which were managed with primary stabilization with pinless fixator and early exchange nailing. Outcome was evaluated in terms of fracture union and rate of residual infection. The data were compared with that available in the literature. Results: All the cases were followed up for a period of 2 years. The study includes Gustilo type 1 (n=10), 14 Gustilo type 2 (n=14), and type3 (n=6) cases. 6 cases (20%) had clamp site infection, 2 cases (6.7%) had deep infection, and in 28 cases (93%) the fracture healed and consolidated well. Conclusion: This study has highlighted the valuable role of pinless external fixator in the management of open tibial fractures in terms of safety and ease of application as well as the advantage of early conversion to intramedullary implant without the risk of deep infection. PMID:19753227
NASA Astrophysics Data System (ADS)
Fleury, Gérard; Mistrot, Pierre
2006-12-01
While driving off-road vehicles, operators are exposed to whole-body vibration acting in the fore-and-aft direction. Seat manufacturers supply products equipped with fore-and-aft suspension but only a few studies report on their performance. This work proposes a computational approach to design fore-and-aft suspensions for wheel loader seats. Field tests were conducted in a quarry to analyse the nature of vibration to which the driver was exposed. Typical input signals were recorded to be reproduced in the laboratory. Technical specifications are defined for the suspension. In order to evaluate the suspension vibration attenuation performance, a model of a sitting human body was developed and coupled to a seat model. The seat model combines the models of each suspension component. A linear two-degree-of-freedom model is used to describe the dynamic behaviour of the sitting driver. Model parameters are identified by fitting the computed apparent mass frequency response functions to the measured values. Model extensions are proposed to investigate postural effects involving variations in hands and feet positions and interaction of the driver's back with the backrest. Suspension design parameters are firstly optimized by computing the seat/man model response to sinusoidal acceleration. Four criteria including transmissibility, interaction force between the driver's back and the backrest and relative maximal displacement of the suspension are computed. A new suspension design with optimized features is proposed. Its performance is checked from calculations of the response of the seat/man model subjected to acceleration measured on the wheel loader during real work conditions. On the basis of the computed values of the SEAT factors, it is found possible to design a suspension that would increase the attenuation provided by the seat by a factor of two.
Henriksen, M; Hunter, D J; Dam, E B; Messier, S P; Andriacchi, T P; Lohmander, L S; Aaboe, J; Boesen, M; Gudbergsen, H; Bliddal, H; Christensen, R
2013-12-01
To investigate whether increased knee joint loading due to improved ambulatory function and walking speed following weight loss achieved over 16 weeks accelerates symptomatic and structural disease progression over a subsequent 1 year weight maintenance period in an obese population with knee osteoarthritis (OA). Data from a prospective study of weight loss in obese patients with knee OA (the CARtilage in obese knee OsteoarThritis (CAROT) study) were used to determine changes in knee joint compressive loadings (model estimated) during walking after a successful 16 week weight loss intervention. The participants were divided into 'Unloaders' (participants that reduced joint loads) and 'Loaders' (participants that increased joint loads). The primary symptomatic outcome was changes in knee symptoms, measured with the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire, during a subsequent 52 weeks weight maintenance period. The primary structural outcome was changes in tibiofemoral cartilage loss assessed semi-quantitatively (Boston Leeds Knee Osteoarthritis Score (BLOKS) from MRI after the 52 weight maintenance period. 157 participants (82% of the CAROT cohort) with medial and/or lateral knee OA were classified as Unloaders (n = 100) or Loaders (n = 57). The groups showed similar significant changes in symptoms (group difference: -2.4 KOOS points [95% CI -6.8:1.9]) and cartilage loss (group difference: -0.06 BLOKS points [95% CI -0.22:0.11) after 1 year, with no statistically significant differences between Loaders and Unloaders. For obese patients undergoing a significant weight loss, increased knee joint loading for 1 year was not associated with accelerated symptomatic and structural disease progression compared to a similar weight loss group that had reduced ambulatory compressive knee joint loads. NCT00655941. Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
Abdullah, Newaj; Rahbar, Haider; Barod, Ravi; Dalela, Deepansh; Larson, Jeff; Johnson, Michael; Mass, Alon; Zargar, Homayoun; Kaouk, Jihad; Allaf, Mohamad; Bhayani, Sam; Stifelman, Michael; Rogers, Craig
2017-03-01
A Satinsky clamp may be a backup option for hilar clamping during robotic partial nephrectomy (RPN) if there are challenges with application of bulldog clamps, but there are potential safety concerns. We evaluate outcomes of RPN using Satinsky vs. bulldog clamps, and provide tips for safe use of the Satinsky as a backup option. Using a multi-center database, we identified 1073 patients who underwent RPN between 2006 and 2013, and had information available about method of hilar clamping (bulldog clamp vs. Satinsky clamp). Patient baseline characteristics, tumor features, and perioperative outcomes were compared between the Satinsky and bulldog clamp groups. A Satinsky clamp was used for hilar clamping in 94 (8.8 %) RPN cases, and bulldog clamps were used in 979 (91.2 %) cases. The use of a Satinsky clamp was associated with greater operative time (198 vs. 175 min, p < 0.001), estimated blood loss (EBL, 200 vs. 100 ml, p < 0.001), warm ischemia time (WIT, 20 vs. 19 min, p = 0.036), transfusion rate (12.8 vs. 4.8 %, p = 0.001), and hospital stay (3 vs. 2 days, p < 0.001). Tumor characteristics and number of renal vessels were similar between groups. There were six intraoperative complications in the Satinsky clamp group, but none were directly related to the Satinsky clamp. On multivariable analysis, the use of the Satinsky clamp was not associated with increase in intraoperative or Clavien ≥3 postoperative complications, positive surgical margin rate or percentage change in estimated glomerular filtration rate. A Satinsky clamp can be a backup option for hilar clamping during challenging RPN cases, but requires careful technique, and was rarely necessary.
NASA Astrophysics Data System (ADS)
Crane, Nicole J.; Huffman, Scott W.; Alemozaffar, Mehrdad; Gage, Frederick A.; Levin, Ira W.; Elster, Eric A.
2013-03-01
Renal ischemia that occurs intraoperatively during procedures requiring clamping of the renal artery (such as renal procurement for transplantation and partial nephrectomy for renal cancer) is known to have a significant impact on the viability of that kidney. To better understand the dynamics of intraoperative renal ischemia and recovery of renal oxygenation during reperfusion, a visible reflectance imaging system (VRIS) was developed to measure renal oxygenation during renal artery clamping in both cooled and warm porcine kidneys. For all kidneys, normothermic and hypothermic, visible reflectance imaging demonstrated a spatially distinct decrease in the relative oxy-hemoglobin concentration (%HbO2) of the superior pole of the kidney compared to the middle or inferior pole. Mean relative oxy-hemoglobin concentrations decrease more significantly during ischemia for normothermic kidneys compared to hypothermic kidneys. VRIS may be broadly applicable to provide an indicator of organ ischemia during open and laparoscopic procedures.
Effect of sterilization on stiffness and dimensional stability of rubber-dam clamps.
Giebink, D L; Mathieu, G P; Hondrum, S O
1996-01-01
Simulated clinical conditions were used to test the effect of sterilization on rubber-dam clamp stiffness and dimension. Sixty Hygienic and Ivory W7 clamps were either steam or dry heat sterilized and compared to controls. Stiffness and dimensional change between Ivory clamp groups was significant (p<.0001); the sterilized clamps showed less change than the controls. Hygienic groups showed a significant different between the control and dry heat groups (p<.05); the sterilized clamps showed less change than the controls. The change in stiffness and interjaw width for all Ivory clamps compared to all Hygienic clamps was significant (p<.0001). The Hygienic clamps changes less than the Ivory clamps. The results indicate that steam and dry heat sterilization do not affect retention of rubber-dam clamps.
Real world duty cycles and utilization for construction equipment in North Carolina.
DOT National Transportation Integrated Search
2008-01-04
Field data for in-use fuel consumption and emission rates were collected for 15 nonroad vehicles using a portable emission : measurement system (PEMS). Each vehicle, including 5 backhoes, 4 front end loaders, and 6 motor graders, were tested : once o...
Comparison of simulator fidelity model predictions with in-simulator evaluation data
NASA Technical Reports Server (NTRS)
Parrish, R. V.; Mckissick, B. T.; Ashworth, B. R.
1983-01-01
A full factorial in simulator experiment of a single axis, multiloop, compensatory pitch tracking task is described. The experiment was conducted to provide data to validate extensions to an analytic, closed loop model of a real time digital simulation facility. The results of the experiment encompassing various simulation fidelity factors, such as visual delay, digital integration algorithms, computer iteration rates, control loading bandwidths and proprioceptive cues, and g-seat kinesthetic cues, are compared with predictions obtained from the analytic model incorporating an optimal control model of the human pilot. The in-simulator results demonstrate more sensitivity to the g-seat and to the control loader conditions than were predicted by the model. However, the model predictions are generally upheld, although the predicted magnitudes of the states and of the error terms are sometimes off considerably. Of particular concern is the large sensitivity difference for one control loader condition, as well as the model/in-simulator mismatch in the magnitude of the plant states when the other states match.
Volvo CE to expand driveline components and introduce new loader concept at bauma
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
2007-04-15
This suppliers news report includes a description of Volvo CE's Graphic wheel loader which uses an electric hybrid power sources and is almost emissions free. Simulator training technology is proving its usefulness in establishing higher safety levels in the mining industry. Immersive Technologies Advanced Equipment training simulators are being used to train students at the Academy for Mine Training and Energy Technology in West Virginia. Geo-Explorer core drills manufactured by Multi-Power Products Ltd. of Canada have been purchased by the Pan African Mining Corp. One is to be assigned to the company's coal program where an extensive exploration program ismore » underway in the Sakoa area in Madagascar. A joint venture agreement has been announced between iPackets International and China's Henan YongAn Investment Guarantee Co. and China Coal Information Institute. Under the name GuoAn Mine Safety Communication System, iPacket's wireless communications software and equipment will be deployed in China's mining industry. 3 photos.« less
Mayton, Alan G.; Jobes, Christopher C.; Gallagher, Sean
2015-01-01
To further assess vibration exposure on haul trucks (HTs) and front-end wheel loaders (FELs), follow-up investigations were conducted at two US crushed stone operations. The purpose was to: 1) evaluate factors such as load/no-load conditions, speed, load capacity, vehicle age, and seat transmissibility relative to vibration exposure; 2) compare exposure levels with existing ISO/ANSI and EUGPG guidelines. Increasing HT speed increased recorded vibration at the chassis and seat as expected. Neither vehicle load nor vehicle speed increased transmissibility. Increasing HT size and age did show transmissibility decreasing. HT dominant-axis wRMS levels (most often the y-axis, lateral or side-to-side direction) were predominantly within the health guidance caution zone (HGCZ). However, several instances showed vibration dose value (VDV) above the exposure limit value (ELV) for the ISO/ANSI guidelines. VDV levels (all dominant x-axis or fore-aft) were within and above the HGCZ for the EUGPG and above the HGCZ for ISO/ANSI guidelines. PMID:26361493
Design and performance tests of a distributed power-driven wheel loader
NASA Astrophysics Data System (ADS)
Jin, Xiaolin; Shi, Laide; Bian, Yongming
2010-03-01
An improved ZLM15B distributed power-driven wheel loader was designed, whose travel and brake system was accomplished by two permanent magnet synchronous motorized-wheels instead of traditional mechanical components, and whose hydraulic systems such as the working device system and steering system were both actuated by an induction motor. All above systems were flexibly coupled with 3-phase 380VAC electric power with which the diesel engine power is replaced. On the level cement road, traveling, braking, traction and steering tests were carried out separately under non-load and heavy-load conditions. Data show that machine speed is 5 km/h around and travel efficiency of motorized-wheels is above 95%; that machine braking deceleration is between 0.5 and 0.64 m/s2 but efficiency of motorized-wheels is less than 10%; that maximum machine traction is above 2t while efficiency of motorized-wheels is more than 90% and that adaptive differential steering can be smoothly achieved by motorized-wheels.
Design and performance tests of a distributed power-driven wheel loader
NASA Astrophysics Data System (ADS)
Jin, Xiaolin; Shi, Laide; Bian, Yongming
2009-12-01
An improved ZLM15B distributed power-driven wheel loader was designed, whose travel and brake system was accomplished by two permanent magnet synchronous motorized-wheels instead of traditional mechanical components, and whose hydraulic systems such as the working device system and steering system were both actuated by an induction motor. All above systems were flexibly coupled with 3-phase 380VAC electric power with which the diesel engine power is replaced. On the level cement road, traveling, braking, traction and steering tests were carried out separately under non-load and heavy-load conditions. Data show that machine speed is 5 km/h around and travel efficiency of motorized-wheels is above 95%; that machine braking deceleration is between 0.5 and 0.64 m/s2 but efficiency of motorized-wheels is less than 10%; that maximum machine traction is above 2t while efficiency of motorized-wheels is more than 90% and that adaptive differential steering can be smoothly achieved by motorized-wheels.
Clamping characteristics study on different types of clamping unit
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jiao, Zhiwei; Liu, Haichao; Xie, Pengcheng
2015-05-22
Plastic products are becoming more and more widely used in aerospace, IT, digital electronics and many other fields. With the development of technology, the requirement of product precision is getting higher and higher. However, type and working performance of clamping unit play a decisive role in product precision. Clamping characteristics of different types of clamping unit are discussed in this article, which use finite element numerical analysis method through the software ABAQUS to study the clamping uniformity, and detect the clamping force repeatability precision. The result shows that compared with toggled three-platen clamping unit, clamping characteristics of internal circulation two-platenmore » clamping unit are better, for instance, its mold cavity deformation and force that bars and mold parting surface suffered are more uniform, and its clamping uniformity and repeatability precision is also better.« less
Method of making dished ion thruster grids
NASA Technical Reports Server (NTRS)
Banks, B. A. (Inventor)
1975-01-01
A pair of flat grid blanks are clamped together at their edges with an impervious metal sheet on top. All of the blanks and sheets are dished simultaneously by forcing fluid to inflate an elastic sheet which contacts the bottom grid blank. A second impervious metal sheet is inserted between the two grid blanks if the grids have high percentage open areas. The dished grids are stress relieved simultaneously.
Air Bag Applies Uniform Bonding Pressure
NASA Technical Reports Server (NTRS)
Gillespie, C. A.
1982-01-01
Air-bag box applies constant uniform pressure to tiles and other objects undergoing adhesive bonding. Box is basically a compliant clamp with adjustable force and position. Can be used on irregular surfaces as well as on flat ones. Pressurized air is fed to bag through a tube so that it expands, filling the box and pressing against work. Bag adopts a contour that accommodates surface under open side of box.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ullah, Ghanim; Demuro, Angelo; Parker, Ian
Amyloid beta (Aβ) oligomers associated with Alzheimer’s disease (AD) form Ca 2+-permeable plasma membrane pores, leading to a disruption of the otherwise well-controlled intracellular calcium (Ca 2+) homeostasis. The resultant up-regulation of intracellular Ca 2+ concentration has detrimental implications for memory formation and cell survival. The gating kinetics and Ca 2+ permeability of Aβ pores are not well understood. We have used computational modeling in conjunction with the ability of optical patch-clamping for massively parallel imaging of Ca 2+ flux through thousands of pores in the cell membrane of Xenopus oocytes to elucidate the kinetic properties of Aβ pores. Themore » fluorescence time-series data from individual pores were idealized and used to develop data-driven Markov chain models for the kinetics of the Aβ pore at different stages of its evolution. Our study provides the first demonstration of developing Markov chain models for ion channel gating that are driven by optical-patch clamp data with the advantage of experiments being performed under close to physiological conditions. As a result, we demonstrate the up-regulation of gating of various Ca 2+ release channels due to Aβ pores and show that the extent and spatial range of such up-regulation increases as Aβ pores with low open probability and Ca 2+ permeability transition into those with high open probability and Ca 2+ permeability.« less
Newman, Jonathan P.; Zeller-Townson, Riley; Fong, Ming-Fai; Arcot Desai, Sharanya; Gross, Robert E.; Potter, Steve M.
2013-01-01
Single neuron feedback control techniques, such as voltage clamp and dynamic clamp, have enabled numerous advances in our understanding of ion channels, electrochemical signaling, and neural dynamics. Although commercially available multichannel recording and stimulation systems are commonly used for studying neural processing at the network level, they provide little native support for real-time feedback. We developed the open-source NeuroRighter multichannel electrophysiology hardware and software platform for closed-loop multichannel control with a focus on accessibility and low cost. NeuroRighter allows 64 channels of stimulation and recording for around US $10,000, along with the ability to integrate with other software and hardware. Here, we present substantial enhancements to the NeuroRighter platform, including a redesigned desktop application, a new stimulation subsystem allowing arbitrary stimulation patterns, low-latency data servers for accessing data streams, and a new application programming interface (API) for creating closed-loop protocols that can be inserted into NeuroRighter as plugin programs. This greatly simplifies the design of sophisticated real-time experiments without sacrificing the power and speed of a compiled programming language. Here we present a detailed description of NeuroRighter as a stand-alone application, its plugin API, and an extensive set of case studies that highlight the system’s abilities for conducting closed-loop, multichannel interfacing experiments. PMID:23346047
The 1990-1991 project summaries
NASA Technical Reports Server (NTRS)
1991-01-01
Project summaries for 1990-91 at the Georgia Institute of Technology are presented. The following research projects were studied: a lunar surface vehicle model; lunar loader/transporter; trenching and cable-laying device for the lunar surface; a lunar vehicle system for habitat transport and placement; and lunar storage facility.
Non-accident release of hazmat from railroad tank cars : training issues
DOT National Transportation Integrated Search
1999-07-01
This report presents the results of a study to determine the extent to which written materials used in training railroad tank car HAZMAT loaders are consistent with the reading skills of the trainees. Data from four case study sites was used to condu...
30 CFR 56.14106 - Falling object protection.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Falling object protection. 56.14106 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 57.14106 - Falling object protection.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Falling object protection. 57.14106 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 56.14106 - Falling object protection.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Falling object protection. 56.14106 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 57.14106 - Falling object protection.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Falling object protection. 57.14106 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 56.14106 - Falling object protection.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Falling object protection. 56.14106 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 57.14106 - Falling object protection.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Falling object protection. 57.14106 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 57.14106 - Falling object protection.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Falling object protection. 57.14106 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 57.14106 - Falling object protection.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Falling object protection. 57.14106 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 56.14106 - Falling object protection.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Falling object protection. 56.14106 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
30 CFR 56.14106 - Falling object protection.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Falling object protection. 56.14106 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14106 Falling object protection. (a) Fork-lift trucks, front-end loaders, and bulldozers shall be provided with falling object protective structures if...
Radiological tele-immersion for next generation networks.
Ai, Z; Dech, F; Rasmussen, M; Silverstein, J C
2000-01-01
Since the acquisition of high-resolution three-dimensional patient images has become widespread, medical volumetric datasets (CT or MR) larger than 100 MB and encompassing more than 250 slices are common. It is important to make this patient-specific data quickly available and usable to many specialists at different geographical sites. Web-based systems have been developed to provide volume or surface rendering of medical data over networks with low fidelity, but these cannot adequately handle stereoscopic visualization or huge datasets. State-of-the-art virtual reality techniques and high speed networks have made it possible to create an environment for clinicians geographically distributed to immersively share these massive datasets in real-time. An object-oriented method for instantaneously importing medical volumetric data into Tele-Immersive environments has been developed at the Virtual Reality in Medicine Laboratory (VRMedLab) at the University of Illinois at Chicago (UIC). This networked-VR setup is based on LIMBO, an application framework or template that provides the basic capabilities of Tele-Immersion. We have developed a modular general purpose Tele-Immersion program that automatically combines 3D medical data with the methods for handling the data. For this purpose a DICOM loader for IRIS Performer has been developed. The loader was designed for SGI machines as a shared object, which is executed at LIMBO's runtime. The loader loads not only the selected DICOM dataset, but also methods for rendering, handling, and interacting with the data, bringing networked, real-time, stereoscopic interaction with radiological data to reality. Collaborative, interactive methods currently implemented in the loader include cutting planes and windowing. The Tele-Immersive environment has been tested on the UIC campus over an ATM network. We tested the environment with 3 nodes; one ImmersaDesk at the VRMedLab, one CAVE at the Electronic Visualization Laboratory (EVL) on east campus, and a CT scan machine in UIC Hospital. CT data was pulled directly from the scan machine to the Tele-Immersion server in our Laboratory, and then the data was synchronously distributed by our Onyx2 Rack server to all the VR setups. Instead of permitting medical volume visualization at one VR device, by combining teleconferencing, tele-presence, and virtual reality, the Tele-Immersive environment will enable geographically distributed clinicians to intuitively interact with the same medical volumetric models, point, gesture, converse, and see each other. This environment will bring together clinicians at different geographic locations to participate in Tele-Immersive consultation and collaboration.
[Single channel analysis of aconitine blockade of calcium channels in rat myocardiocytes].
Chen, L; Ma, C; Cai, B C; Lu, Y M; Wu, H
1995-01-01
Ventricular myocardiocytes from neonatal Wistar rats were isolated and cultured. Aconitine, Ca2+ channel blocker verapamil or Ca2+ channel activator BAY K8644 were added to the bath solution separately. Using the cell-attached configuration of the patch clamp technique, the single channel activities of L type Ca2+ channel were recorded before and after addition of all three drugs. The results showed the blocking effect of aconitine (50 micrograms.ml-1) on L type Ca2+ channels. Its mechanism may be relevant to the decrease in both open state probability and the mean open time of Ca2+ channel. The difference was statistically significant compared with control group (P < 0.01). The amplitude of Ba2+ currents, which flow through open L type Ca2+ channel was unchanged.
Pemp, Berthold; Polska, Elżbieta; Garhofer, Gerhard; Bayerle-Eder, Michaela; Kautzky-Willer, Alexandra; Schmetterer, Leopold
2010-01-01
OBJECTIVE To compare total retinal blood flow in diabetic patients with no or mild nonproliferative diabetic retinopathy and healthy control subjects and to investigate in patients whether there is a difference between retinal blood flow before morning insulin and under normoglycemic conditions using a glucose clamp. RESEARCH DESIGN AND METHODS Twenty patients with type 1 diabetes with no or mild diabetic retinopathy were included in this open parallel-group study, and 20 healthy age- and sex-matched subjects were included as control subjects. Retinal blood flow was assessed by combining velocity measurements using laser Doppler velocimetry and diameter measurements using a commercially available dynamic vessel analyzer. Measurements were performed before and during a euglycemic clamp. RESULTS Total retinal blood flow was higher in diabetic patients (53 ± 16 μl/min) than in healthy subjects (43 ± 16 μl/min; P = 0.034 between groups). When plasma glucose in diabetic patients was reduced from 9.3 ± 1.7 to 5.3 ± 0.5 mmol/l (P < 0.001) retinal blood flow decreased to 49 ± 15 μl/min (P = 0.0003 vs. baseline). Total retinal blood flow during the glucose clamp was not significantly different from blood flow in normal control subjects (P = 0.161). CONCLUSIONS Type 1 diabetic patients with no or only mild diabetic retinopathy have increased retinal blood flow before their morning insulin dosage. Blood flow is reduced toward normal during euglycemic conditions. Retinal blood flow may fluctuate significantly with fluctuating plasma glucose levels, which may contribute to the microvascular changes seen in diabetic retinopathy. PMID:20585003
Biton, B; Sethuramanujam, S; Picchione, Kelly E; Bhattacharjee, A; Khessibi, N; Chesney, F; Lanneau, C; Curet, O; Avenet, P
2012-03-01
Sodium-activated potassium (K(Na)) channels have been suggested to set the resting potential, to modulate slow after-hyperpolarizations, and to control bursting behavior or spike frequency adaptation (Trends Neurosci 28:422-428, 2005). One of the genes that encodes K(Na) channels is called Slack (Kcnt1, Slo2.2). Studies found that Slack channels were highly expressed in nociceptive dorsal root ganglion neurons and modulated their firing frequency (J Neurosci 30:14165-14172, 2010). Therefore, Slack channel openers are of significant interest as putative analgesic drugs. We screened the library of pharmacologically active compounds with recombinant human Slack channels expressed in Chinese hamster ovary cells, by using rubidium efflux measurements with atomic absorption spectrometry. Riluzole at 500 μM was used as a reference agonist. The antipsychotic drug loxapine and the anthelmintic drug niclosamide were both found to activate Slack channels, which was confirmed by using manual patch-clamp analyses (EC(50) = 4.4 μM and EC(50) = 2.9 μM, respectively). Psychotropic drugs structurally related to loxapine were also evaluated in patch-clamp experiments, but none was found to be as active as loxapine. Loxapine properties were confirmed at the single-channel level with recombinant rat Slack channels. In dorsal root ganglion neurons, loxapine was found to behave as an opener of native K(Na) channels and to increase the rheobase of action potential. This study identifies new K(Na) channel pharmacological tools, which will be useful for further Slack channel investigations.
30 CFR 46.5 - New miner training.
Code of Federal Regulations, 2010 CFR
2010-07-01
... the recognition and avoidance of electrical hazards and other hazards present at the mine, such as traffic patterns and control, mobile equipment (e.g., haul trucks and front-end loaders), and loose or... aspects of an assigned task in paragraph (b)(4) of this section, if hazard recognition training specific...
30 CFR 46.5 - New miner training.
Code of Federal Regulations, 2011 CFR
2011-07-01
... the recognition and avoidance of electrical hazards and other hazards present at the mine, such as traffic patterns and control, mobile equipment (e.g., haul trucks and front-end loaders), and loose or... aspects of an assigned task in paragraph (b)(4) of this section, if hazard recognition training specific...
Hydrographic Service Royal Australian Navy
1993-01-01
relocation of the Hydrographic Office to Wollongong, NSW; "* A marked decline in chart production caused by workforce changes as a result of the impending...amalgamate the plans of Clinton Coal Loader Wharf and Auckland Point to Barney Point in one plan at scale 1:10 000. The chart now provides continuous
Index to Benet Weapons Laboratory (LCWSL) Technical Reports - 1979
1980-09-01
Breech Machanisms Breech Seals Breeches, Cannon Cadmium Sulfide Calibration Cannon Auto Loader Cannon Tube Chemical Vapor Deposition REPORT NUMBER...PAGE(Trh«n Data SntaracQ (Con1t from block #20) Three basic specimen geometries were studied: 1. A symetric specimen; 2. A specimen with +5% wall
Federal Workplace Literacy Project. Internal Evaluation Report.
ERIC Educational Resources Information Center
Matuszak, David J.
This report describes the following components of the Nestle Workplace Literacy Project: six job task analyses, curricula for six workplace basic skills training programs, delivery of courses using these curricula, and evaluation of the process. These six job categories were targeted for training: forklift loader/checker, BB's processing systems…
Standard Electronic Format Specification for Tank Characterization Data Loader Version 3.5
DOE Office of Scientific and Technical Information (OSTI.GOV)
ADAMS, M.R.
2001-01-31
The purpose of this document is to describe the standard electronic format for data files that will be sent for entry into the Tank Characterization Database (TCD). There are 2 different file types needed for each data load: (1) Analytical Results and (2) Sample Descriptions.
Low-Capital Systems for Thinning Pine Plantations
John Wilhoit; Qingyue Ling; Robert Rummer
1999-01-01
Highly mechanized systems utilizing rubber-tired skidders, feller-bunchers, and knuckleboom loaders are the predominant type of timber harvesting operation in the southern United States. These systems, which handle the wood in tree-length form, are highly productive and very efficient, especially for large tracts of timber. Thinnings constitute an increasing proportion...
Code of Federal Regulations, 2011 CFR
2011-07-01
... loaders. This machinery is also excluded when used with chains, slings or other rigging to lift suspended... that deliver material to a construction site when the crane is used to transfer building supply sheet goods or building supply packaged materials from the truck crane onto a structure, using a fork/cradle...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-26
... protective equipment to protect miners from harmful levels of noise that can result in hearing loss. However..., relies on drills, crushers, compressors, conveyors, trucks, loaders, and other heavy-duty equipment for the excavation, haulage, and processing of material. This equipment creates high sound levels...
77 FR 16865 - Proposed Extension of Existing Information Collection; Occupational Noise Exposure
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-22
..., administrative controls, and personal protective equipment to protect miners from harmful levels of noise that..., compressors, conveyors, trucks, loaders, and other heavy-duty equipment for the excavation, haulage, and processing of material. This equipment creates high sound levels, exposing machine operators as well as...
Automatic tracking of cells for video microscopy in patch clamp experiments
2014-01-01
Background Visualisation of neurons labeled with fluorescent proteins or compounds generally require exposure to intense light for a relatively long period of time, often leading to bleaching of the fluorescent probe and photodamage of the tissue. Here we created a technique to drastically shorten light exposure and improve the targeting of fluorescent labeled cells that is specially useful for patch-clamp recordings. We applied image tracking and mask overlay to reduce the time of fluorescence exposure and minimise mistakes when identifying neurons. Methods Neurons are first identified according to visual criteria (e.g. fluorescence protein expression, shape, viability etc.) and a transmission microscopy image Differential Interference Contrast (DIC) or Dodt contrast containing the cell used as a reference for the tracking algorithm. A fluorescence image can also be acquired later to be used as a mask (that can be overlaid on the target during live transmission video). As patch-clamp experiments require translating the microscope stage, we used pattern matching to track reference neurons in order to move the fluorescence mask to match the new position of the objective in relation to the sample. For the image processing we used the Open Source Computer Vision (OpenCV) library, including the Speeded-Up Robust Features (SURF) for tracking cells. The dataset of images (n = 720) was analyzed under normal conditions of acquisition and with influence of noise (defocusing and brightness). Results We validated the method in dissociated neuronal cultures and fresh brain slices expressing Enhanced Yellow Fluorescent Protein (eYFP) or Tandem Dimer Tomato (tdTomato) proteins, which considerably decreased the exposure to fluorescence excitation, thereby minimising photodamage. We also show that the neuron tracking can be used in differential interference contrast or Dodt contrast microscopy. Conclusion The techniques of digital image processing used in this work are an important addition to the set of microscopy tools used in modern electrophysiology, specially in experiments with neuron cultures and brain slices. PMID:24946774
Automatic tracking of cells for video microscopy in patch clamp experiments.
Peixoto, Helton M; Munguba, Hermany; Cruz, Rossana M S; Guerreiro, Ana M G; Leao, Richardson N
2014-06-20
Visualisation of neurons labeled with fluorescent proteins or compounds generally require exposure to intense light for a relatively long period of time, often leading to bleaching of the fluorescent probe and photodamage of the tissue. Here we created a technique to drastically shorten light exposure and improve the targeting of fluorescent labeled cells that is specially useful for patch-clamp recordings. We applied image tracking and mask overlay to reduce the time of fluorescence exposure and minimise mistakes when identifying neurons. Neurons are first identified according to visual criteria (e.g. fluorescence protein expression, shape, viability etc.) and a transmission microscopy image Differential Interference Contrast (DIC) or Dodt contrast containing the cell used as a reference for the tracking algorithm. A fluorescence image can also be acquired later to be used as a mask (that can be overlaid on the target during live transmission video). As patch-clamp experiments require translating the microscope stage, we used pattern matching to track reference neurons in order to move the fluorescence mask to match the new position of the objective in relation to the sample. For the image processing we used the Open Source Computer Vision (OpenCV) library, including the Speeded-Up Robust Features (SURF) for tracking cells. The dataset of images (n = 720) was analyzed under normal conditions of acquisition and with influence of noise (defocusing and brightness). We validated the method in dissociated neuronal cultures and fresh brain slices expressing Enhanced Yellow Fluorescent Protein (eYFP) or Tandem Dimer Tomato (tdTomato) proteins, which considerably decreased the exposure to fluorescence excitation, thereby minimising photodamage. We also show that the neuron tracking can be used in differential interference contrast or Dodt contrast microscopy. The techniques of digital image processing used in this work are an important addition to the set of microscopy tools used in modern electrophysiology, specially in experiments with neuron cultures and brain slices.
Transcription initiation complex structures elucidate DNA opening.
Plaschka, C; Hantsche, M; Dienemann, C; Burzinski, C; Plitzko, J; Cramer, P
2016-05-19
Transcription of eukaryotic protein-coding genes begins with assembly of the RNA polymerase (Pol) II initiation complex and promoter DNA opening. Here we report cryo-electron microscopy (cryo-EM) structures of yeast initiation complexes containing closed and open DNA at resolutions of 8.8 Å and 3.6 Å, respectively. DNA is positioned and retained over the Pol II cleft by a network of interactions between the TATA-box-binding protein TBP and transcription factors TFIIA, TFIIB, TFIIE, and TFIIF. DNA opening occurs around the tip of the Pol II clamp and the TFIIE 'extended winged helix' domain, and can occur in the absence of TFIIH. Loading of the DNA template strand into the active centre may be facilitated by movements of obstructing protein elements triggered by allosteric binding of the TFIIE 'E-ribbon' domain. The results suggest a unified model for transcription initiation with a key event, the trapping of open promoter DNA by extended protein-protein and protein-DNA contacts.
Cacciamani, Giovanni E; Medina, Luis G; Gill, Tania S; Mendelsohn, Alec; Husain, Fatima; Bhardwaj, Lokesh; Artibani, Walter; Sotelo, Renè; Gill, Inderbir S
2018-02-05
During robotic partial nephrectomy (RPN), various techniques of hilar control have been described, including on-clamp, early unclamping, selective/super-selective clamping, and completely-unclamped RPN. To evaluate the impact of various hilar control techniques on perioperative, functional, and oncological outcomes of RPN for tumors. We conducted a systematic literature review and meta-analysis of all comparative studies on various hilar control techniques during RPN using PubMed, Scopus, and Web of Science according to the Preferred Reporting Items for Systematic Review and Meta-analysis statement, and Methods and Guide for Effectiveness and Comparative Effectiveness Review of the Agency for Healthcare Research and Quality. Cumulative meta-analysis of comparative studies was conducted using Review Manager 5.3. Of 987 RPN publications in the literature, 19 qualified for this analysis. Comparison of off-clamp versus on-clamp RPN (n=9), selective clamping versus on-clamp RPN (n=3), super selective clamping versus on-clamp RPN (n=5), and early unclamped versus on-clamp (n=3) were reported. Patients undergoing RPN using off-clamp, selective/super selective, or early unclamp techniques had higher estimated blood loss compared with on-clamp RPN (weight mean difference [WMD]: 47.83, p=0.000, WMD: 41.06, p=0.02, and WMD: 37.50, p=0.47); however, this did not seem clinically relevant, since transfusion rates were similar (odds ratio [OR]: 0.98, p=0.95, OR: 0.72, p=0.7, and OR: 1.36, p=0.33, respectively). All groups appeared similar with regards to hospital stay, transfusions, overall and major complications, and positive cancer margin rates. Short- and long-term renal functional outcomes appeared superior in the off-clamp and super selective clamp groups compared with the on-clamp RPN cohort. Off-clamp, selective/super selective clamp, and early unclamp hilar control techniques are safe and feasible approaches for RPN surgery, with similar perioperative and oncological outcomes compared with on-clamp RPN. Minimizing global renal ischemia may provide superior renal function preservation. However, higher quality data are necessary for definitive conclusions in this regard. The objective of partial nephrectomy is to treat the cancer while maximizing renal function preservation. Clamping the main vessels is done primarily to reduce the blood loss during partial nephrectomy; however, vascular clamping can compromise kidney function. In order to avoid clamping, various techniques have been described. Our analysis showed that techniques that avoid main renal artery clamping during RPN are associated with better renal function preservation, yet deliver non-inferior perioperative and oncological outcomes as compared with robotic partial nephrectomy procedures that clamp the main vessels. Copyright © 2018 European Association of Urology. Published by Elsevier B.V. All rights reserved.
Clamp usable as jig and lifting clamp
Tsuyama, Yoshizo
1976-01-01
There is provided a clamp which is well suited for use as a lifting clamp for lifting and moving materials of assembly in a shipyard, etc. and as a pulling jig in welding and other operations. The clamp comprises a clamp body including a shackle for engagement with a pulling device and a slot for receiving an article, and a pair of jaws provided on the leg portions of the clamp body on the opposite sides of the slot to grip the article in the slot, one of said jaws consisting of a screw rod and the other jaw consisting of a swivel jaw with a spherical surface, whereby when the article clamped in the slot by the pair of jaws tends to slide in any direction with respect to the clamp body, the article is more positively gripped by the pair of jaws.
Split-tapered joint clamping device
Olsen, Max J.; Schwartz, Jr., John F.
1988-01-01
This invention relates to a clamping device for removably attaching a tool element to a bracket element wherein a bracket element is disposed in a groove in the tool and a clamping member is disposed in said groove and in engagement with a clamping face of the bracket and a wall of the groove and with the clamping member having pivot means engaging the bracket and about which the clamping member rotates.
Umul, M; Cal, A C; Turna, B; Oktem, G; Aydın, H H
2016-01-01
To evaluate the effect of temporary complete hilar versus only renal artery clamping with different duration of warm ischemia on renal functions, and possibly identify a "safe" clamping type and duration of renal ischemia. Fifty male rabbits have been incorporated to study. Rabbits were subjected to ischemia/reperfusion injury by temporary vascular clamping. Reagents were randomized to 3 experimental groups (only renal artery clamping, complete hilar clamping, sham surgery) and sub-groups were determined according to different clamping times (30 and 60 minutes). Median laparotomy and left renal hilus dissection were performed to sham group. Only artery or complete hilar clamping was performed for 30 or 60 minutes by microvascular bulldog clamps to other reagents. Rabbits were sacrificed 10 days after primary surgery and left nephrectomy performed. Nephrectomy materials were evaluated for the level of nitric-oxide synthase (NOS) immunoreactivity, malondialdehyde (MDA) level and superoxide dismutase (SOD) activity and an electron microscopic examination was performed. NOS immunoreactivity was correlated with the temporary clamping time. We also observed that complete hilar vascular clamping entails an increase on NOS immunoreactivity. MDA levels were similar for all experimental surgery groups (p = 0.42). The SOD activity was decreased among all subgroups compared with sham surgery. But the significant decrease occurred in 30 minutes only artery and 30 minutes complete hilar clamping groups in proportion to sham surgery (p = 0.026 and p = 0.019, respectively). This current study suggested that only renal artery clamping under 30 minutes is more appropriate during renal surgical procedures requiring temporary vascular clamping.
Environmental and economic analyses of waste disposal options for traditional markets in Indonesia.
Aye, Lu; Widjaya, E R
2006-01-01
Waste from traditional markets in Indonesia is the second largest stream of municipal solid waste after household waste. It has a higher organic fraction and may have greater potential to be managed on a business scale compared to household wastes. The attributed reason is that in general the wastes generated from traditional markets are more uniform, more concentrated and less hazardous than waste from other sources. This paper presents the results of environmental and economic assessments to compare the options available for traditional market waste disposal in Indonesia. The options compared were composting in labour intensive plants, composting in a centralised plant that utilised a simple wheel loader, centralised biogas production and landfill for electricity production. The current open dumping practice was included as the baseline case. A life cycle assessment (LCA) was used for environmental analysis. All options compared have lower environmental impacts than the current practice of open dumping. The biogas production option has the lowest environmental impacts. A cost-benefit analysis, which considered greenhouse gas savings, was used for the economic assessment. It was found that composting at a centralised plant is the most economically feasible option under the present Indonesian conditions. The approach reported in this study could be applied for 'a pre-feasibility first cut comparison' that includes environmental aspects in a decision-making framework for developing countries even though European emission factors were used.
Bailey, Damian M; Evans, Tom G; Thomas, Kate Gower; White, Richard D; Twine, Chistopher P; Lewis, Michael H; Williams, Ian M
2016-08-01
What is the central question of this study? To what extent focal abdominal aortic aneurysmal (AAA) disease is associated with systemic remodelling of the vascular tree remains unknown. The present study examined whether anatomical differences exist between distances of the intervisceral artery origins and AAA location/size in patients with disease compared with healthy patients. What is the main finding and its importance? Intervisceral artery distances were shown to be consistently greater in AAA patients, highlighting the systemic nature of AAA disease that extends proximally to the abdominal aorta and its branches. The anatomical description of the natural variation in visceral artery origins has implications for the design of stent grafts and planning complex open aortic surgery. The initial histopathology of abdominal aortic aneurysmal (AAA) disease is atherosclerotic, later diverting towards a distinctive dilating rather than occlusive aortic phenotype. To what extent focal AAA disease is associated with systemic remodelling of the vascular tree remains unknown. The present study examined whether anatomical differences exist between the intervisceral artery origins and AAA location/size in patients with AAA disease (AAA+) relative to those without (AAA-). Preoperative contrast-enhanced computerized tomograms were reviewed in 90 consecutive AAA+ patients scheduled for open repair who underwent an infrarenal (n = 45), suprarenal (n = 26) or supracoeliac clamp (n = 19). These were compared with 39 age-matched AAA- control patients. Craniocaudal measurements were recorded from the distal origin of the coeliac artery to the superior mesenteric artery and from the origin of the superior mesenteric artery to both renal artery origins. Serial blood samples were obtained for estimation of the glomerular filtration rate before and after surgery. Intervisceral artery origins were shown to be consistently greater in AAA+ patients (P < 0.05 versus AAA-), although unrelated to AAA diameter (P > 0.05). Postoperative renal function became progressively more impaired the more proximal the clamp placement (estimated glomerular filtration rate for supracoeliac < suprarenal < infrarenal clamps, P < 0.05). These findings highlight the systemic nature of AAA disease that extends proximally to the abdominal aorta and its branches. The anatomical description of the natural variation in visceral artery origins has implications for the design of stent grafts and planning complex open aortic surgery. © 2016 The Authors. Experimental Physiology © 2016 The Physiological Society.
Lifting clamp positively grips structural shapes
NASA Technical Reports Server (NTRS)
Reinhardt, E. C.
1966-01-01
Welded steel clamps securely grip structural shapes of various sizes for crane operations. The clamp has adjustable clamping jaws and screw-operated internal v-jaws and provides greater safety than hoisting slings presently used. The structural member can be rotated in any manner, angle, or direction without being released by the clamp.
30 CFR Appendix I to Subpart M of... - National Consensus Standards
Code of Federal Regulations, 2013 CFR
2013-07-01
... loaders and bulldozers Society of Automotive Engineers (SAE) minimum performance criteria for falling object protective structures (FOPS) SAE J231—January, 1981. Fork-lift trucks American National Standards Institute (ANSI) safety standard for low lift and high lift trucks, B 56.1, section 7.27—1983; or, American...
30 CFR Appendix I to Subpart M of... - National Consensus Standards
Code of Federal Regulations, 2014 CFR
2014-07-01
... loaders and bulldozers Society of Automotive Engineers (SAE) minimum performance criteria for falling object protective structures (FOPS) SAE J231—January, 1981. Fork-lift trucks American National Standards Institute (ANSI) safety standard for low lift and high lift trucks, B 56.1, section 7.27—1983; or, American...
30 CFR Appendix I to Subpart M of... - National Consensus Standards
Code of Federal Regulations, 2012 CFR
2012-07-01
... loaders and bulldozers Society of Automotive Engineers (SAE) minimum performance criteria for falling object protective structures (FOPS) SAE J231—January, 1981. Fork-lift trucks American National Standards Institute (ANSI) safety standard for low lift and high lift trucks, B 56.1, section 7.27—1983; or, American...
30 CFR Appendix I to Subpart M of... - National Consensus Standards
Code of Federal Regulations, 2013 CFR
2013-07-01
... loaders and bulldozers Society of Automotive Engineers (SAE) minimum performance criteria for falling object protective structures (FOPS) SAE J231—January, 1981. Fork-lift trucks American National Standards Institute (ANSI) safety standard for low lift and high lift trucks, B 56.1, section 7.27—1983; or American...
30 CFR Appendix I to Subpart M of... - National Consensus Standards
Code of Federal Regulations, 2012 CFR
2012-07-01
... loaders and bulldozers Society of Automotive Engineers (SAE) minimum performance criteria for falling object protective structures (FOPS) SAE J231—January, 1981. Fork-lift trucks American National Standards Institute (ANSI) safety standard for low lift and high lift trucks, B 56.1, section 7.27—1983; or American...
30 CFR Appendix I to Subpart M of... - National Consensus Standards
Code of Federal Regulations, 2014 CFR
2014-07-01
... loaders and bulldozers Society of Automotive Engineers (SAE) minimum performance criteria for falling object protective structures (FOPS) SAE J231—January, 1981. Fork-lift trucks American National Standards Institute (ANSI) safety standard for low lift and high lift trucks, B 56.1, section 7.27—1983; or American...
30 CFR 46.6 - Newly hired experienced miner training.
Code of Federal Regulations, 2010 CFR
2010-07-01
...) Instruction on the recognition and avoidance of electrical hazards and other hazards present at the mine, such as traffic patterns and control, mobile equipment (e.g., haul trucks and front-end loaders), and... health and safety aspects of an assigned task in paragraph (b)(4) of this section, if hazard recognition...
30 CFR 46.6 - Newly hired experienced miner training.
Code of Federal Regulations, 2011 CFR
2011-07-01
...) Instruction on the recognition and avoidance of electrical hazards and other hazards present at the mine, such as traffic patterns and control, mobile equipment (e.g., haul trucks and front-end loaders), and... health and safety aspects of an assigned task in paragraph (b)(4) of this section, if hazard recognition...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-22
...] Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting AGENCY: Food and... of Committee: Circulatory System Devices Panel of the Medical Devices Advisory Committee. General... also comes with a sheath, introducer, loader, dilator, balloon (used to pre-dilate the native annulus...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-27
...] Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting AGENCY: Food and... of Committee: Circulatory System Devices Panel of the Medical Devices Advisory Committee. General..., introducer, loader, dilator, balloon (used to pre-dilate the native annulus) and a crimper. FDA intends to...
40 CFR Table 9 to Subpart Wwww of... - Initial Compliance With Work Practice Standards
Code of Federal Regulations, 2014 CFR
2014-07-01
... compression/injection molding uncover, unwrap or expose only one charge per mold cycle per compression/injection molding machine. For machines with multiple molds, one charge means sufficient material to fill... cycle per compression/injection molding machine, or prior to the loader, hoppers are closed except when...
background-color: #e5e5e5; } h3 { line-height: 20px; padding-bottom: 10px; } #appheader { margin ; position: relative; text-align: center; font-size: 16pt; /*font-weight: bold;*/ /*color: rgb(165,180,212 );*/ color: rgb(62, 96, 163); background: url('../images/ajax-loader.gif') 50% 50% no-repeat; } .container
The Impact of Wireless Technology on Loading Trucks at an Auto Parts Distribution Center
ERIC Educational Resources Information Center
Goomas, David T.
2012-01-01
An intervention was introduced for truck loaders that used wireless vehicle mount computers that included auditory, visual feedback, and immediate data delivery. The implementation reliably reduced pallets from being loaded out of sequence for all outbound trucks in multistop routes. The role of the organizational behavior management (OBM)…
NASA Astrophysics Data System (ADS)
Nguyen, K. L.; Gabov, V. V.; Zadkov, D. A.; Le, T. B.
2018-03-01
This paper analyzes the processes of removing coal from the area of its dislodging and loading the disintegrated mass onto face conveyors by auger heads of shearer-loader machines. The loading process is assumed to consist of four subprocesses: dislodging coal, removal of the disintegrated mass by auger blades from the crushing area, passive transportation of the disintegrated mass, and forming the load flow on the bearing surface of a face conveyor. Each of the considered subprocesses is different in its physical nature, the number of factors influencing it, and can be complex or multifactor. Possibilities of improving the efficiency of loading coal onto a face conveyor are addressed. The selected criteria of loading efficiency are load rate, specific energy consumption, and coal size reduction. Efficiency is improved by reducing the resistance to movement of the disintegrated mass during loading by increasing the area of the loading window section and the volume of the loading area on the conveyor, as well as by coordination of intensity of flows related to the considered processes in local areas.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robitaille, H.A.
1983-09-01
The M-744 APFSDS anti-tank round contains a depleted-uranium penetrator of 3.4 kgram mass. Since depleted uranium is naturally radioactive, the storage of a substantial number of these rounds inside a Leopard C-1 main battle tank creates a gamma radiation field within the vehicle. Gamma-ray exposure rates have been measured using a sodium-iodide spectrometer at each of the four crew-member locations and for two turret orientations, with 59 rounds stowed in the vehicle. In all cases the measured gamma-ray dose rates were less than a maximum of 0.17 millirad per hour observed at the loader's position. Assuming the loader spent anmore » entire week (168 hours) at his station, his integrated dose would amount to 29 mRad - approximately a factor of 4 lower than the maximum currently allowed by Canadian Forces regulations. It is therefore concluded that the M774 round does not represent a significant gamma radiation hazard to Leopard C1 crewmembers.« less
Selective Arterial Clamping Versus Hilar Clamping for Minimally Invasive Partial Nephrectomy.
Yezdani, Mona; Yu, Sue-Jean; Lee, David I
2016-05-01
Partial nephrectomy has become an accepted treatment of cT1 renal masses as it provides improved long-term renal function compared to radical nephrectomy (Campbell et al. J Urol. 182:1271-9, 2009). Hilar clamping is utilized to help reduce bleeding and improve visibility during tumor resection. However, concern over risk of kidney injury with hilar clamping has led to new techniques to reduce length of warm ischemia time (WIT) during partial nephrectomy. These techniques have progressed over the years starting with early hilar unclamping, controlled hypotension during tumor resection, selective arterial clamping, minimal margin techniques, and off-clamp procedures. Selective arterial clamping has progressed significantly over the years. The main question is what are the exact short- and long-term renal effects from increasing clamp time. Moreover, does it make sense to perform these more time-consuming or more complex procedures if there is no long-term preservation of kidney function? More recent studies have shown no difference in renal function 6 months from surgery when selective arterial clamping or even hilar clamping is employed, although there is short-term improved decline in estimated glomerular filtration rate (eGFR) with selective clamping and off-clamp techniques (Komninos et al. BJU Int. 115:921-8, 2015; Shah et al. 117:293-9, 2015; Kallingal et al. BJU Int. doi: 10.1111/bju.13192, 2015). This paper reviews the progression of total hilar clamping to selective arterial clamping (SAC) and the possible difference its use makes on long-term renal function. SAC may be attempted based on surgeon's decision-making, but may be best used for more complex, larger, more central or hilar tumors and in patients who have renal insufficiency at baseline or a solitary kidney.
Upadhye, Kalpesh V.; Candiello, Joseph E.; Davidson, Lance A.; Lin, Hai
2011-01-01
Patch clamp is a powerful tool for studying the properties of ion-channels and cellular membrane. In recent years, planar patch clamp chips have been fabricated from various materials including glass, quartz, silicon, silicon nitride, polydimethyl-siloxane (PDMS), and silicon dioxide. Planar patch clamps have made automation of patch clamp recordings possible. However, most planar patch clamp chips have limitations when used in combination with other techniques. Furthermore, the fabrication methods used are often expensive and require specialized equipments. An improved design as well as fabrication and characterization of a silicon-based planar patch clamp chip are described in this report. Fabrication involves true batch fabrication processes that can be performed in most common microfabrication facilities using well established MEMS techniques. Our planar patch clamp chips can form giga-ohm seals with the cell plasma membrane with success rate comparable to existing patch clamp techniques. The chip permits whole-cell voltage clamp recordings on variety of cell types including Chinese Hamster Ovary (CHO) cells and pheochromocytoma (PC12) cells, for times longer than most available patch clamp chips. When combined with a custom microfluidics chamber, we demonstrate that it is possible to perfuse the extra-cellular as well as intra-cellular buffers. The chamber design allows integration of planar patch clamp with atomic force microscope (AFM). Using our planar patch clamp chip and microfluidics chamber, we have recorded whole-cell mechanosensitive (MS) currents produced by directly stimulating human keratinocyte (HaCaT) cells using an AFM cantilever. Our results reveal the spatial distribution of MS ion channels and temporal details of the responses from MS channels. The results show that planar patch clamp chips have great potential for multi-parametric high throughput studies of ion channel proteins. PMID:22174731
Ullah, Ghanim; Demuro, Angelo; Parker, Ian; ...
2015-09-08
Amyloid beta (Aβ) oligomers associated with Alzheimer’s disease (AD) form Ca 2+-permeable plasma membrane pores, leading to a disruption of the otherwise well-controlled intracellular calcium (Ca 2+) homeostasis. The resultant up-regulation of intracellular Ca 2+ concentration has detrimental implications for memory formation and cell survival. The gating kinetics and Ca 2+ permeability of Aβ pores are not well understood. We have used computational modeling in conjunction with the ability of optical patch-clamping for massively parallel imaging of Ca 2+ flux through thousands of pores in the cell membrane of Xenopus oocytes to elucidate the kinetic properties of Aβ pores. Themore » fluorescence time-series data from individual pores were idealized and used to develop data-driven Markov chain models for the kinetics of the Aβ pore at different stages of its evolution. Our study provides the first demonstration of developing Markov chain models for ion channel gating that are driven by optical-patch clamp data with the advantage of experiments being performed under close to physiological conditions. As a result, we demonstrate the up-regulation of gating of various Ca 2+ release channels due to Aβ pores and show that the extent and spatial range of such up-regulation increases as Aβ pores with low open probability and Ca 2+ permeability transition into those with high open probability and Ca 2+ permeability.« less
Method of making a catalytic reactor for automobile
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vroman, W.R.
1976-09-07
A catalytic reactor is made by providing a generally cylindrical catalytic substrate of oval transverse section and clamping the same between paired housing shells to form a housing of oval section spaced from the substrate by means of a pair of wire mesh ropes seated within a corresponding pair of grooves extending around the periphery of the substrate at axially spaced locations. Each rope is compacted from a matrix of multiple layers of resilient stainless steel knitted wire and is interlocked with the housing by means of a pair of inwardly opening channels of the housing spaced axially by anmore » inwardly projecting rib of the housing. The grooves in the substrate are pressed radially into the latter while the same is in a plastic uncured condition, thereby to compact and reinforce the grooves to withstand the localized compressional force of the ropes seated therein after the substrate is cured and hardened and clamped between the housing shells.« less
Huynh, Hai; Elkouri, Stephane; Beaudoin, Nathalie; Bruneau, Luc; Guimond, Cathie; Daniel, Véronique; Blair, Jean-François
2007-01-01
This study evaluated the learning curve for a second-year general surgery resident and compared 2 totally laparoscopic aortic surgery techniques in 10 pigs: the transretroperitoneal apron approach and the transperitoneal retrocolic approach. Five end points were compared: success rate, percentage of conversion, time required, laparoscopic anastomosis quality, and learning curve. The first 3 interventions required an open conversion. The last 7 were done without complications. Mean dissection time was significantly higher with the apron approach compared with the retrocolic approach. The total times for operation, clamping, and arteriotomy time were similar. All laparoscopic anastomoses were patent and without stenosis. The initial learning curve for laparoscopic anastomosis was relatively short for a second-year surgery resident. Both techniques resulted in satisfactory exposure of the aorta and similar mean operative and clamping time. Training on an ex vivo laparoscopic box trainer and on an animal model seems to be complementary to decrease laparoscopic anastomosis completion time.
The dark side of the ring: role of the DNA sliding surface of PCNA.
De March, Matteo; De Biasio, Alfredo
2017-12-01
The proliferating cell nuclear antigen (PCNA) sliding clamp lies at the heart of the accurate duplication of eukaryotic genomes. While the outer surface of the PCNA ring interacts with polymerases and other factors, the role of the inner wall facing the DNA is elusive. Recent evidence shows that conserved basic residues in the PCNA central channel create a specific surface that recognizes the DNA backbone and enables the clamp to slide by rotationally tracking the DNA helix. The sliding surface can be modulated (i) through lysine acetylation, which triggers PCNA degradation during nucleotide excision repair (NER) and stimulates repair by homologous recombination (HR) or (ii) through binding of the protein factor p15 PAF , which turns off DNA lesion bypass. Thus, the inner surface of PCNA is unexpectedly highly regulated to control resistance to DNA damage. From a structural viewpoint, we reflect on these findings that open a new perspective on PCNA function and offer opportunities to develop tools to manipulate the DNA damage response in cancer treatment.
One-channel Cell-attached Patch-clamp Recording
Maki, Bruce A.; Cummings, Kirstie A.; Paganelli, Meaghan A.; Murthy, Swetha E.; Popescu, Gabriela K.
2014-01-01
Ion channel proteins are universal devices for fast communication across biological membranes. The temporal signature of the ionic flux they generate depends on properties intrinsic to each channel protein as well as the mechanism by which it is generated and controlled and represents an important area of current research. Information about the operational dynamics of ion channel proteins can be obtained by observing long stretches of current produced by a single molecule. Described here is a protocol for obtaining one-channel cell-attached patch-clamp current recordings for a ligand gated ion channel, the NMDA receptor, expressed heterologously in HEK293 cells or natively in cortical neurons. Also provided are instructions on how to adapt the method to other ion channels of interest by presenting the example of the mechano-sensitive channel PIEZO1. This method can provide data regarding the channel’s conductance properties and the temporal sequence of open-closed conformations that make up the channel’s activation mechanism, thus helping to understand their functions in health and disease. PMID:24961614
USDA-ARS?s Scientific Manuscript database
To compare beta-cell function relative to insulin sensitivity, disposition index (DI), calculated from two clamps (2cDI, insulin sensitivity from the hyperinsulinemic-euglycemic clamp and first-phase insulin from the hyperglycemic clamp) with the DI calculated from the hyperglycemic clamp alone (hcD...
21 CFR 882.4460 - Neurosurgical head holder (skull clamp).
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Neurosurgical head holder (skull clamp). 882.4460... holder (skull clamp). (a) Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures. (b...
Microchip amplifier for in vitro, in vivo, and automated whole cell patch-clamp recording
Kolb, Ilya; Kodandaramaiah, Suhasa B.; Chubykin, Alexander A.; Yang, Aimei; Bear, Mark F.; Boyden, Edward S.; Forest, Craig R.
2014-01-01
Patch clamping is a gold-standard electrophysiology technique that has the temporal resolution and signal-to-noise ratio capable of reporting single ion channel currents, as well as electrical activity of excitable single cells. Despite its usefulness and decades of development, the amplifiers required for patch clamping are expensive and bulky. This has limited the scalability and throughput of patch clamping for single-ion channel and single-cell analyses. In this work, we have developed a custom patch-clamp amplifier microchip that can be fabricated using standard commercial silicon processes capable of performing both voltage- and current-clamp measurements. A key innovation is the use of nonlinear feedback elements in the voltage-clamp amplifier circuit to convert measured currents into logarithmically encoded voltages, thereby eliminating the need for large high-valued resistors, a factor that has limited previous attempts at integration. Benchtop characterization of the chip shows low levels of current noise [1.1 pA root mean square (rms) over 5 kHz] during voltage-clamp measurements and low levels of voltage noise (8.2 μV rms over 10 kHz) during current-clamp measurements. We demonstrate the ability of the chip to perform both current- and voltage-clamp measurement in vitro in HEK293FT cells and cultured neurons. We also demonstrate its ability to perform in vivo recordings as part of a robotic patch-clamping system. The performance of the patch-clamp amplifier microchip compares favorably with much larger commercial instrumentation, enabling benchtop commoditization, miniaturization, and scalable patch-clamp instrumentation. PMID:25429119
Mittan, Margaret Birmingham [Oakland, CA; Miros, Robert H. J. [Fairfax, CA; Brown, Malcolm P [San Francisco, CA; Stancel, Robert [Loss Altos Hills, CA
2012-06-05
A photovoltaic panel clamp includes an upper and lower section. The interface between the assembled clamp halves and the module edge is filled by a flexible gasket material, such as EPDM rubber. The gasket preferably has small, finger like protrusions that allow for easy insertion onto the module edge while being reversed makes it more difficult to remove them from the module once installed. The clamp includes mounting posts or an integral axle to engage a bracket. The clamp also may include a locking tongue to secure the clamp to a bracket.
Brown, Malcolm P.; Mittan, Margaret Birmingham; Miros, Robert H. J.; Stancel, Robert
2013-03-19
A photovoltaic panel clamp includes an upper and lower section. The interface between the assembled clamp halves and the module edge is filled by a flexible gasket material, such as EPDM rubber. The gasket preferably has small, finger like protrusions that allow for easy insertion onto the module edge while being reversed makes it more difficult to remove them from the module once installed. The clamp includes mounting posts or an integral axle to engage a bracket. The clamp also may include a locking tongue to secure the clamp to a bracket.
Sinusoidal voltage protocols for rapid characterisation of ion channel kinetics.
Beattie, Kylie A; Hill, Adam P; Bardenet, Rémi; Cui, Yi; Vandenberg, Jamie I; Gavaghan, David J; de Boer, Teun P; Mirams, Gary R
2018-03-24
Ion current kinetics are commonly represented by current-voltage relationships, time constant-voltage relationships and subsequently mathematical models fitted to these. These experiments take substantial time, which means they are rarely performed in the same cell. Rather than traditional square-wave voltage clamps, we fitted a model to the current evoked by a novel sum-of-sinusoids voltage clamp that was only 8 s long. Short protocols that can be performed multiple times within a single cell will offer many new opportunities to measure how ion current kinetics are affected by changing conditions. The new model predicts the current under traditional square-wave protocols well, with better predictions of underlying currents than literature models. The current under a novel physiologically relevant series of action potential clamps is predicted extremely well. The short sinusoidal protocols allow a model to be fully fitted to individual cells, allowing us to examine cell-cell variability in current kinetics for the first time. Understanding the roles of ion currents is crucial to predict the action of pharmaceuticals and mutations in different scenarios, and thereby to guide clinical interventions in the heart, brain and other electrophysiological systems. Our ability to predict how ion currents contribute to cellular electrophysiology is in turn critically dependent on our characterisation of ion channel kinetics - the voltage-dependent rates of transition between open, closed and inactivated channel states. We present a new method for rapidly exploring and characterising ion channel kinetics, applying it to the hERG potassium channel as an example, with the aim of generating a quantitatively predictive representation of the ion current. We fitted a mathematical model to currents evoked by a novel 8 second sinusoidal voltage clamp in CHO cells overexpressing hERG1a. The model was then used to predict over 5 minutes of recordings in the same cell in response to further protocols: a series of traditional square step voltage clamps, and also a novel voltage clamp comprising a collection of physiologically relevant action potentials. We demonstrate that we can make predictive cell-specific models that outperform the use of averaged data from a number of different cells, and thereby examine which changes in gating are responsible for cell-cell variability in current kinetics. Our technique allows rapid collection of consistent and high quality data, from single cells, and produces more predictive mathematical ion channel models than traditional approaches. © 2018 The Authors. The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.
NASA Technical Reports Server (NTRS)
Belrose, Charles R. (Inventor)
1994-01-01
A saddle clamp assembly is presented. The assembly is comprised of a hollow cylindrical body centered about a longitudinal axis and being diametrically split into semicircular top and bottom sections. Each section has a pair of connection flanges, at opposite ends, that project radially outward. A pair of bolts are retained on the top section flanges and are threadable into nuts retained on the bottom section flanges. A base member is anchored to a central underside portion of the bottom clamp body section and has a pair of connection tabs positioned beneath the bottom clamp body section connection flanges on opposite sides of the clamp axis. A pair of bolts are retained on the base member connection tabs and are threadable into a pair of nuts retainable on a support structure. The connection tab and connection flanges on each side of the clamp body are axially offset in a manner permitting downward installation/removable tool access to the lower bolts past the connection flanges. An elongated retention tether is used to connect the top clamp body section to the balance of the clamp assembly. This prevents loss of the top clamp body section when it is removed from the bottom clamp body section.
46 CFR 128.420 - Keel cooler installations.
Code of Federal Regulations, 2013 CFR
2013-10-01
...-metallic hose-clamps may be used at machinery connections if— (1) The clamps are of a corrosion-resistant material; (2) The clamps do not depend on spring tension for their holding power; and (3) Two of the clamps...
High throughput ion-channel pharmacology: planar-array-based voltage clamp.
Kiss, Laszlo; Bennett, Paul B; Uebele, Victor N; Koblan, Kenneth S; Kane, Stefanie A; Neagle, Brad; Schroeder, Kirk
2003-02-01
Technological advances often drive major breakthroughs in biology. Examples include PCR, automated DNA sequencing, confocal/single photon microscopy, AFM, and voltage/patch-clamp methods. The patch-clamp method, first described nearly 30 years ago, was a major technical achievement that permitted voltage-clamp analysis (membrane potential control) of ion channels in most cells and revealed a role for channels in unimagined areas. Because of the high information content, voltage clamp is the best way to study ion-channel function; however, throughput is too low for drug screening. Here we describe a novel breakthrough planar-array-based HT patch-clamp technology developed by Essen Instruments capable of voltage-clamping thousands of cells per day. This technology provides greater than two orders of magnitude increase in throughput compared with the traditional voltage-clamp techniques. We have applied this method to study the hERG K(+) channel and to determine the pharmacological profile of QT prolonging drugs.
2016-06-06
the widely used lead zirconate titanate ceramics which have a typical piezoelectric coefficient d31 of ~- 200pC/N, PMN-PT single crystals used in...substrate clamping effect, therefore, a relatively giant tunability can be obtained. However, the normally large roughness of piezoelectric layer...is the saturation magnetostriction constant, Y the Young’s modulus of the magnetic film, deff the effective piezoelectric coefficient, E
Feasibility Study of a Precision Cast Loading Machine for Small Ammunition Items
1975-05-01
distribution unlimited. READ INStRUCTIONS BEFORE COMPLETING FORM 1. RECIPIENT’S CATALOG NUMBER S. TYRE OF REPORT « PERIOD COVERED S. PCRFORMINO ORO...through a short length rubber hose into the hemisphere. A clamp actuated by an air cylinder can close or open the rubber hose. Because of unknown... rubber hose in the recess on the face of the fixture, exposing opposite hole for observation by the TV monitor through the TV camera. 8. Release table
M60 Tank Personnel Heater Comparison Test, Fort Carson, Colorado
1983-05-01
A study should be made considering the logisites and cost implications of developing a kit to upgrade the Model "C" heater to include self ...l f L Summary of Questionnaire Respose -for BLU (Model "A" with Engine Filter/Heat Tape) System Driver Loader Gunner TC’* " # % # % * % # 9 12. Heat
29 CFR 782.8 - Special classes of carriers.
Code of Federal Regulations, 2013 CFR
2013-07-01
..., and ice) to railroad, docks, etc., for use of trains and steamships is not such transportation as is... cases cited in § 782.7(c), and see Mitchell v. Independent Ice Co., 294 F. 2d 186 (C.A. 5), certiorari..., driver's helpers, loaders, and mechanics employed by companies engaged in such activities are covered by...
29 CFR 782.8 - Special classes of carriers.
Code of Federal Regulations, 2014 CFR
2014-07-01
..., and ice) to railroad, docks, etc., for use of trains and steamships is not such transportation as is... cases cited in § 782.7(c), and see Mitchell v. Independent Ice Co., 294 F. 2d 186 (C.A. 5), certiorari..., driver's helpers, loaders, and mechanics employed by companies engaged in such activities are covered by...
29 CFR 782.8 - Special classes of carriers.
Code of Federal Regulations, 2012 CFR
2012-07-01
..., and ice) to railroad, docks, etc., for use of trains and steamships is not such transportation as is... cases cited in § 782.7(c), and see Mitchell v. Independent Ice Co., 294 F. 2d 186 (C.A. 5), certiorari..., driver's helpers, loaders, and mechanics employed by companies engaged in such activities are covered by...
Chapter 5: Loosening compacted soils on mined lands
B. Strahm; R. Sweigard; J. Burger; D. Graves; C. Zipper; C. Barton; J. Skousen; P. Angel
2017-01-01
Successful surface coal mining businesses must move earth materials efficiently, so mining operations today depend on large and heavy equipment (Fig. 5-1). Track dozers and haul trucks used for mining can weigh more than 100 tons each. Wheel loaders and loaded haul trucks often exceed 200 tons. The mining industry has learned that successful reforestation of reclaimed...
2008-09-24
Aeronautics Technical Seminar series: Pilot Force Measurement with Inertia and Gravity Compensation by Rodger A. Mueller (offering an interesting behind-the-scenes look at some of the research that goes into creating high-fedelity, pilot-control loader simulation experiences for pilots and astronauts using the world renowned NASA Ames Vertical Motion Simulator) Series audio on file in Ames Library
2008-09-24
Aeroanutics Technical Seminar series: Pilot Force Measurement with Inertia and Gravity Compensation by Rodger A. Mueller (offering an interesting behind-the-scenes look at some of the research that goes into creating high-fedelity, pilot-control loader simulation experiences for pilots and astronauts using the world renowned NASA Ames Vertical Motion Simulator) Series audio on file in Ames Library
2008-09-24
Aeroanutics Technical Seminar series: Pilot Force Measurement with Inertia and Gravity Compensation by Rodger A. Mueller (offering an interesting behind-the-scenes look at some of the research that goes into creating high-fedelity, pilot-control loader simulation experiences for pilots and astronauts using the world renowned NASA Ames Vertical Motion Simulator) Series audio on file in Ames Library
76 FR 37795 - Notice of Availability of Government-Owned Inventions; Available for Licensing
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-28
... DEPARTMENT OF DEFENSE Department of the Navy Notice of Availability of Government-Owned Inventions....S. Patent No. 7,316,194: Rudders for High-Speed Ships//U.S. Patent No. 7,322,786: Mobile Loader for Transfer of Containers Between Delivery Vehicles and Marine Terminal Cranes//U.S. Patent No. 7,324,016...
Department of Defense In-House RDT&E Activities
1981-10-30
DISEASES*.’......*......... 43 MISSILE LABORATORY ................................................. 44 MOBILITY EQUIPMENT R&D COMMAND...HELICOPTER INFLIGHT MONITORING SYS WITH INSTRUMENTED RANGE; ANECHOIC AND REVERBERATION CHAMBERS; MOBILE -’ ACCOUSTICS LAB; EYE MOVEMENT MEASURING...IN- CLUDES: LIGHTWEIGIHT OPTICAL TRACKING SYSTEM, 25-TON CRANE, 2 20-TON MOBILE CRANES, 5-TON WRECKER, 40,000 LB ACFT LOADER, THREE T-28B ACFT, 1 UH
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-12
... counterbalanced lift truck is a rigid framed, engine- powered machine with lift arms that has additional weight...; \\7\\ (2) construction vehicles and equipment, including earthmover articulated dump products, rigid frame haul trucks,\\8\\ front end loaders,\\9\\ dozers,\\10\\ lift trucks, straddle carriers,\\11\\ graders,\\12...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morris, John; Gilchrist, Phillip Charles
Processes, systems, devices, and articles of manufacture are provided. Each may include adapting micro-inverters initially configured for frame-mounting to mounting on a frameless solar panel. This securement may include using an adaptive clamp or several adaptive clamps secured to a micro-inverter or its components, and using compressive forces applied directly to the solar panel to secure the adaptive clamp and the components to the solar panel. The clamps can also include compressive spacers and safeties for managing the compressive forces exerted on the solar panels. Friction zones may also be used for managing slipping between the clamp and the solarmore » panel during or after installation. Adjustments to the clamps may be carried out through various means and by changing the physical size of the clamps themselves.« less
A novel high performance ESD power clamp circuit with a small area
NASA Astrophysics Data System (ADS)
Zhaonian, Yang; Hongxia, Liu; Li, Li; Qingqing, Zhuo
2012-09-01
A MOSFET-based electrostatic discharge (ESD) power clamp circuit with only a 10 ns RC time constant for a 0.18-μm process is proposed. A diode-connected NMOSFET is used to maintain a long delay time and save area. The special structure overcomes other shortcomings in this clamp circuit. Under fast power-up events, the gate voltage of the clamp MOSFET does not rise as quickly as under ESD events, the special structure can keep the clamp MOSFET thoroughly off. Under a falsely triggered event, the special structure can turn off the clamp MOSFET in a short time. The clamp circuit can also reject the power supply noise effectively. Simulation results show that the clamp circuit avoids fast false triggering events such as a 30 ns/1.8 V power-up, maintains a 1.2 μs delay time and a 2.14 μs turn-off time, and reduces to about 70% of the RC time constant. It is believed that the proposed clamp circuit can be widely used in high-speed integrated circuits.
NASA Technical Reports Server (NTRS)
Young, Ken (Inventor); Hindle, Timothy (Inventor); Barber, Tim Daniel (Inventor)
2016-01-01
Mounting systems for structural members, fastening assemblies thereof, and vibration isolation systems including the same are provided. Mounting systems comprise a pair of mounting brackets, each clamped against a fastening assembly forming a mounting assembly. Fastening assemblies comprise a spherical rod end comprising a spherical member having a through opening and an integrally threaded shaft, first and second seating members on opposite sides of the spherical member and each having a through opening that is substantially coaxial with the spherical member through opening, and a partially threaded fastener that threadably engages each mounting bracket forming the mounting assembly. Structural members have axial end portions, each releasably coupled to a mounting bracket by the integrally threaded shaft. Axial end portions are threaded in opposite directions for permitting structural member rotation to adjust a length thereof to a substantially zero strain position. Structural members may be vibration isolator struts in vibration isolation systems.
Battery with modular air cathode and anode cage
Niksa, Marilyn J.; Pohto, Gerald R.; Lakatos, Leslie K.; Wheeler, Douglas J.; Niksa, Andrew J.; Schue, Thomas J.
1987-01-01
A battery assembly of the consumable metal anode type has now been constructed for ready assembly as well as disassembly. In a non-conductive and at least substantially inert cell body, space is provided for receiving an open-structured, non-consumable anode cage. The cage has an open top for facilitating insertion of an anode. A modular cathode is used, comprising a peripheral current conductor frame clamped about a grid reinforced air cathode in sheet form. The air cathode may be double gridded. The cathode frame can be sealed, during assembly, with electrolyte-resistant-sealant as well as with adhesive. The resulting cathode module can be assembled outside the cell body and readily inserted therein, or can later be easily removed therefrom.
Battery with modular air cathode and anode cage
Niksa, Marilyn J.; Pohto, Gerald R.; Lakatos, Leslie K.; Wheeler, Douglas J.; Niksa, Andrew J.; Schue, Thomas J.; Turk, Thomas R.
1988-01-01
A battery assembly of the consumable metal anode type has now been constructed for ready assembly as well as disassembly. In a non-conductive and at least substantially inert cell body, space is provided for receiving an open-structured, non-consumable anode cage. The cage has an open top for facilitating insertion of an anode. A modular cathode is used, comprising a peripheral current conductor frame clamped about a grid reinforced air cathode in sheet form. The air cathode may be double gridded. The cathode frame can be sealed, during assembly, with electrolyte-resistant-sealant as well as with adhesive. The resulting cathode module can be assembled outside the cell body and readily inserted therein, or can later be easily removed therefrom.
Method of making a unitized electrode assembly
Niksa, Marilyn J.; Pohto, Gerald R.; Lakatos, Leslie K.; Wheeler, Douglas J.; Solomon, Frank; Niksa, Andrew J.; Schue, Thomas J.; Genodman, Yury; Turk, Thomas R.; Hagel, Daniel P.
1988-01-01
A battery assembly of the consumable metal anode type has now been constructed for ready assembly as well as disassembly. In a non-conductive and at least substantially inert cell body, space is provided for receiving an open-structured, non-consumable anode cage. The cage has an open top for facilitating insertion of an anode. A modular cathode is used, comprising a peripheral current conductor frame clamped about a grid reinforced air cathode in sheet form. The air cathode may be double gridded. The cathode frame can be sealed, during assembly, with electrolyte-resistant-sealant as well as with adhesive. The resulting cathode module can be assembled outside the cell body and readily inserted therein, or can later be easily removed therefrom.
Method of making a unitized electrode assembly
Niksa, M.J.; Pohto, G.R.; Lakatos, L.K.; Wheeler, D.J.; Solomon, F.; Niksa, A.J.; Schue, T.J.; Genodman, Y.; Turk, T.R.; Hagel, D.P.
1988-12-06
A battery assembly of the consumable metal anode type has now been constructed for ready assembly as well as disassembly. In a non-conductive and at least substantially inert cell body, space is provided for receiving an open-structured, non-consumable anode cage. The cage has an open top for facilitating insertion of an anode. A modular cathode is used, comprising a peripheral current conductor frame clamped about a grid reinforced air cathode in sheet form. The air cathode may be double gridded. The cathode frame can be sealed, during assembly, with electrolyte-resistant-sealant as well as with adhesive. The resulting cathode module can be assembled outside the cell body and readily inserted therein, or can later be easily removed therefrom. 6 figs.
Kawakami, Hironori; Su'etsugu, Masayuki; Katayama, Tsutomu
2006-10-01
In Escherichia coli, a complex consisting of Hda and the DNA-loaded clamp-subunit of the DNA polymerase III holoenzyme promotes hydrolysis of DnaA-ATP. The resultant ADP-DnaA is inactive for initiation of chromosomal DNA replication, thereby repressing excessive initiations. As the cellular content of the clamp is 10-100 times higher than that of Hda, most Hda molecules might be complexed with the clamp in vivo. Although Hda predominantly forms irregular aggregates when overexpressed, in the present study we found that co-overexpression of the clamp with Hda enhances Hda solubility dramatically and we efficiently isolated the Hda-clamp complex. A single molecule of the complex appears to consist of two Hda molecules and a single clamp. The complex is competent in DnaA-ATP hydrolysis and DNA replication in the presence of DNA and the clamp deficient subassembly of the DNA polymerase III holoenzyme (pol III*). These findings indicate that the clamp contained in the complex is loaded onto DNA through an interaction with the pol III* and that the Hda activity is preserved in these processes. The complex consisting of Hda and the DNA-unloaded clamp may play a specific role in a process proceeding to the DnaA-ATP hydrolysis in vivo.
Harty, Niall J; Laskey, Daniel H; Moinzadeh, Alireza; Flacke, Sebastian; Benn, James A; Villani, Rosanna; Kalra, Aarti; Libertino, John A; Madras, Peter N
2012-09-01
What's known on the subject? and What does the study add? Lumagel™ is a reverse thermosensitive polymer (RTP) that has previously been described in the literature as providing temporary vascular occlusion to allow for bloodless partial nephrectomy (PN) while maintaining blood flow to the untargeted portion of the kidney. At body temperature, Lumagel™ has the consistency of a viscous gel but upon cooling rapidly converts to a liquid state and does not reconstitute thereafter. This property has allowed for it to be used in situations requiring temporary vascular occlusion. Previous experience with similar RTPs in coronary arteries proved successful, with no detectable adverse events. We have previously described our technique for temporary vascular occlusion of the main renal artery, as well as segmental and sub-segmental renal branches, to allow for bloodless PN in either an open or minimally invasive approach. These experiments were performed in the acute setting. This study is a two-armed survival trial to assess whether this RTP is as safe as hilar clamping for bloodless PN. Surviving animals showed normal growth after using the RTP, absence of toxicity, no organ dysfunction, and no pathological changes attributable to the RTP. We conclude that Lumagel™ is as safe as conventional PN with hilar clamping, while adding the advantage of uninterrupted perfusion during renal resection. To examine whether randomly selected regions of the kidney could undergo temporary flow interruption with a reverse thermosensitive polymer (RTP), Lumagel™ (Pluromed, Inc., Woburn, MA, USA), followed by partial nephrectomy (PN), without adding risks beyond those encountered in the same procedure with the use of hilar clamping. A two-armed (RTP vs hilar clamp), 6-week swine survival study was performed. Four swine underwent PN using hilar clamps, while six underwent PN with flow interruption using the RTP. The RTP, administered angiographically, was used for intraluminal occlusion of segmental or subsegmental arteries and was compared with main renal artery clamping with hilar clamps. The resection site was randomized for each swine. Laboratory studies were performed preoperatively, and at weeks 1, 3 and 6. Before killing the swine, repeat angiography was performed with emphasis on the site of previous flow interruption. Gross and microscopic examination of kidney, liver, lung, heart, skeletal muscle was later performed, and the vessel that had supported the previous plug was examined. All animals survived. No abnormal chemistry or haematology results were encountered over the 6 weeks. There were no surgical complications in either group. Using angiography we found 100% patency of vessels that had been occluded with the polymer 6 weeks previously for PN. The only gross or microscopic abnormalities were related to the renal resection and scar formation, and were similar in the two groups. Targeted flow interruption with the RTP added no additional risk to PN while allowing bloodless resection and uninterrupted flow to untargeted renal tissue. © 2012 THE AUTHORS. BJU INTERNATIONAL © 2012 BJU INTERNATIONAL.
Aeroelastic deformation of a perforated strip
NASA Astrophysics Data System (ADS)
Guttag, M.; Karimi, H. H.; Falcón, C.; Reis, P. M.
2018-01-01
We perform a combined experimental and numerical investigation into the static deformation of perforated elastic strips under uniform aerodynamic loading at high-Reynolds-number conditions. The static shape of the porous strips, clamped either horizontally or vertically, is quantified as they are deformed by wind loading, induced by a horizontal flow. The experimental profiles are compared to numerical simulations using a reduced model that takes into account the normal drag force on the deformed surface. For both configurations (vertical and horizontal clamping), we compute the drag coefficient of the strip, by fitting the experimental data to the model, and find that it decreases as a function of porosity. Surprisingly, we find that, for every value of porosity, the drag coefficients for the horizontal configuration are larger than those of the vertical configuration. For all data in both configurations, with the exception of the continuous strip clamped vertically, a linear relation is found between the porosity and drag. Making use of this linearity, we can rescale the drag coefficient in a way that it becomes constant as a function of the Cauchy number, which relates the force due to fluid loading on the elastic strip to its bending rigidity, independently of the material properties and porosity of the strip and the flow speed. Our findings on flexible strips are contrasted to previous work on rigid perforated plates. These results highlight some open questions regarding the usage of reduced models to describe the deformation of flexible structures subjected to aerodynamic loading.
Welding fixture for joining bar-wound stator conductors
DOE Office of Scientific and Technical Information (OSTI.GOV)
De Souza, Urban J.; Rhoads, Frederick W.; Hanson, Justin
A fixture assembly for welding a plurality of stator wire end pairs may include an anvil, a movable clamp configured to translate between an unclamped state and a clamped state, a first grounding electrode, and a second grounding electrode. The movable clamp may be configured to urge the plurality of stator wire ends against the anvil when in the clamped state. The moveable clamp includes a separator feature that generally extends toward the anvil. Each of the first grounding electrode and second grounding electrodes may be configured to translate between a clamped state and an unclamped state. When in themore » clamped state, each of the first and second grounding electrodes is configured to urge a pair of the plurality of stator wire end pairs against the separator feature.« less
M-currents and other potassium currents in bullfrog sympathetic neurones
Adams, P. R.; Brown, D. A.; Constanti, A.
1982-01-01
1. Bullfrog lumbar sympathetic neurones were voltage-clamped in vitro through twin micro-electrodes. Four different outward (K+) currents could be identified: (i) a large sustained voltage-sensitive delayed rectifier current (IK) activated at membrane potentials more positive than -25 mV; (ii) a calcium-dependent sustained outward current (IC) activated at similar positive potentials and peaking at +20 to +60 mV; (iii) a transient current (IA) activated at membrane potentials more positive than -60 mV after a hyperpolarizing pre-pulse, but which was rapidly and totally inactivated at all potentials within its activation range; and (iv) a new K+ current, the M-current (IM). 2. IM was detected as a non-inactivating current with a threshold at -60 mV. The underlying conductance GM showed a sigmoidal activation curve between -60 and -10 mV, with half-activation at -35 mV and a maximal value (ḠM) of 84±14 (S.E.M.) nS per neurone. The voltage sensitivity of GM could be expressed in terms of a simple Boltzmann distribution for a single multivalent gating particle. 3. IM activated and de-activated along an exponential time course with a time constant uniquely dependent upon voltage, maximizing at ≃ 150 ms at -35 mV at 22 °C. 4. Instantaneous current—voltage (I/V) curves were approximately linear in the presence of IM, suggesting that the M-channels do not show appreciable rectification. However, the time- and voltage-dependent opening of the M-channels induced considerable rectification in the steady-state I/V curves recorded under both voltage-clamp and current-clamp modes between -60 and -25 mV. Both time- and voltage-dependent rectification in the voltage responses to current injection over this range could be predicted from the kinetic properties of IM. 5. It is suggested that IM exerts a strong potential-clamping effect on the behaviour of these neurones at membrane potentials subthreshold to excitation. PMID:6294290
Tryon, David; Myklak, Kristene; Alsyouf, Muhannad; Conceicao, Carol; Peplinski, Brandon; Arenas, Javier L; Faaborg, Daniel; Ruckle, Herbert C; Baldwin, D Duane
2016-03-01
Previous benchtop studies have shown that robotic bulldog clamps provide incomplete vascular control of a Penrose drain. We determined the efficacy of robotic and laparoscopic bulldog clamps to ensure hemostasis on the human renal artery. The effect of clamp position on vascular control was also examined. Fresh human cadaveric renal arteries were used to determine the leak point pressure of 7 bulldog clamps from a total of 3 manufacturers. Five trials were performed per clamp at 4 locations, including the fulcrum, proximal, middle and distal positions. Comparison was done using the Kruskal-Wallis test with p <0.05 considered significant. None of the bulldog clamps leaked at a pressure less than 215 mm Hg when applied at the proximal, middle or distal position. In general leak point pressure decreased as the artery was positioned more distal along the clamp. The exception was when the vessel was placed at the fulcrum position. At that position 80% to 100% of trials with the Klein laparoscopic, 100% with the Klein robotic (Klein Robotic, San Antonio, Texas) and 60% to 80% with the Scanlan robotic (Scanlan International, Saint Paul, Minnesota) clamp leaked at pressure below 215 mm Hg. Each vascular clamp adequately occluded flow at physiological pressure when placed at the proximal, middle or distal position. Furthermore, these results demonstrate that there is leakage at physiological pressure when the artery is placed at the fulcrum of certain clamp types. These results suggest that applying a bulldog clamp at the fulcrum could potentially lead to inadequate vessel occlusion and intraoperative bleeding. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Saad, M F; Anderson, R L; Laws, A; Watanabe, R M; Kades, W W; Chen, Y D; Sands, R E; Pei, D; Savage, P J; Bergman, R N
1994-09-01
An insulin-modified frequently sampled intravenous glucose tolerance test (FSIGTT) with minimal model analysis was compared with the glucose clamp in 11 subjects with normal glucose tolerance (NGT), 20 with impaired glucose tolerance (IGT), and 24 with non-insulin-dependent diabetes mellitus (NIDDM). The insulin sensitivity index (SI) was calculated from FSIGTT using 22- and 12-sample protocols (SI(22) and SI(12), respectively). Insulin sensitivity from the clamp was expressed as SI(clamp) and SIP(clamp). Minimal model parameters were similar when calculated with SI(22) and SI(12). SI could not be distinguished from 0 in approximately 50% of diabetic patients with either protocol. SI(22) correlated significantly with SI(clamp) in the whole group (r = 0.62), and in the NGT (r = 0.53), IGT (r = 0.48), and NIDDM (r = 0.41) groups (P < 0.05 for each). SI(12) correlated significantly with SI(clamp) in the whole group (r = 0.55, P < 0.001) and in the NGT (r = 0.53, P = 0.046) and IGT (r = 0.58, P = 0.008) but not NIDDM (r = 0.30, P = 0.085) groups. When SI(22), SI(clamp), and SIP(clamp) were expressed in the same units, SI(22) was 66 +/- 5% (mean +/- SE) and 50 +/- 8% lower than SI(clamp) and SIP(clamp), respectively. Thus, minimal model analysis of the insulin-modified FSIGTT provides estimates of insulin sensitivity that correlate significantly with those from the glucose clamp. The correlation was weaker, however, in NIDDM. The insulin-modified FSIGTT can be used as a simple test for assessment of insulin sensitivity in population studies involving nondiabetic subjects. Additional studies are needed before using this test routinely in patients with NIDDM.
Arterial waves in humans during peripheral vascular surgery.
Khir, A W; Henein, M Y; Koh, T; Das, S K; Parker, K H; Gibson, D G
2001-12-01
The purpose of this study was to investigate the effect of aortic clamping on arterial waves during peripheral vascular surgery. We measured pressure and velocity simultaneously in the ascending aorta, in ten patients (70+/-5 years) with aortic-iliac disease intra-operatively. Pressure was measured using a catheter tip manometer, and velocity was measured using Doppler ultrasound. Data were collected before aortic clamping, during aortic clamping and after unclamping. Hydraulic work in the aortic root was calculated from the measured data, the reflected waves were determined by wave-intensity analysis and wave speed was determined by the PU-loop (pressure-velocity-loop) method; a new technique based on the 'water-hammer' equation. The wave speed is approx. 32% (P<0.05) higher during clamping than before clamping. Although the peak intensity of the reflected wave does not alter with clamping, it arrives 30 ms (P<0.05) earlier and its duration is 25% (P<0.05) longer than before clamping. During clamping, left ventricule (LV) hydraulic systolic work and the energy carried by the reflected wave increased by 27% (P<0.05) and 20% (P<0.05) respectively, compared with before clamping. The higher wave speed during clamping explains the earlier arrival of the reflected waves suggesting an increase in the afterload, since the LV has to overcome earlier reflected compression waves. The longer duration of the reflected wave during clamping is associated with an increase in the total energy carried by the wave, which causes an increase in hydraulic work. Increased hydraulic work during clamping may increase LV oxygen consumption, provoke myocardial ischaemia and hence contribute to the intra-operative impairment of LV function known in patients with peripheral vascular disease.
Liu, Lilly Y; Feinglass, Joe M; Khan, Janine Y; Gerber, Susan E; Grobman, William A; Yee, Lynn M
2017-05-01
To evaluate adherence to a delayed cord clamping protocol for preterm births in the first 2 years after its introduction, perform a quality improvement assessment, and determine neonatal outcomes associated with protocol implementation and adherence. This is a retrospective cohort study of women delivering singleton neonates at 23-32 weeks of gestation in the 2 years before (preprotocol) and 2 years after (postprotocol) introduction of a 30-second delayed cord clamping protocol at a large-volume academic center. This policy was communicated to obstetric and pediatric health care providers and nurses and reinforced with intermittent educational reviews. Barriers to receiving delayed cord clamping were assessed using χ tests and multivariable logistic regression. Neonatal outcomes then were compared between all neonates in the preprotocol period and all neonates in the postprotocol period and between all neonates in the preprotocol period and neonates receiving delayed cord clamping in the postprotocol period using multivariable linear and logistic regression analyses. Of the 427 eligible neonates, 187 were born postprotocol. Of these, 53.5% (n=100) neonates received delayed cord clamping according to the protocol. The rate of delayed cord clamping preprotocol was 0%. Protocol uptake and frequency of delayed cord clamping increased over the 2 years after its introduction. In the postprotocol period, cesarean delivery was the only factor independently associated with failing to receive delayed cord clamping (adjusted odds ratio [OR] 0.49, 95% confidence interval [CI] 0.25-0.96). In comparison with the preprotocol period, those who received delayed cord clamping in the postprotocol period had significantly higher birth hematocrit (β=2.46, P=.007) and fewer blood transfusions in the first week of life (adjusted OR 0.49, 95% CI 0.25-0.96). After introduction of an institutional delayed cord clamping protocol followed by continued health care provider education and quality feedback, the frequency of delayed cord clamping progressively increased. Compared with historical controls, performing delayed cord clamping in eligible preterm neonates was associated with improved neonatal hematologic indices, demonstrating the effectiveness of delayed cord clamping in a large-volume maternity unit.
A clamped rectangular plate containing a crack
NASA Technical Reports Server (NTRS)
Tang, R.; Erdogan, F.
1985-01-01
The general problem of a rectangular plate clamped along two parallel sides and containing a crack parallel to the clamps is considered. The problem is formulated in terms of a system of singular integral equations and the asymptotic behavior of the stress state near the corners is investigated. Numerical examples are considered for a clamped plate without a crack and with a centrally located crack, and the stress intensity factors and the stresses along the clamps are calculated.
NASA Technical Reports Server (NTRS)
Nunnelee, Mark (Inventor)
2004-01-01
A precision clamp that accurately measures force over a wide range of conditions is described. Using a full bridge or other strain gage configuration. the elastic deformation of the clamp is measured or detected by the strain gages. Thc strain gages transmit a signal that corresponds to the degree of stress upon the clamp. Thc strain gage signal is converted to a numeric display. Calibration is achieved by ero and span potentiometers which enable accurate measurements by the force-measuring clamp.
Allan, David S; Scrivens, Nicholas; Lawless, Tiffany; Mostert, Karen; Oppenheimer, Lawrence; Walker, Mark; Petraszko, Tanya; Elmoazzen, Heidi
2016-03-01
Public banking of umbilical cord blood units (CBUs) containing higher numbers of cells ensures timely engraftment after transplantation for increasing numbers of patients. Delayed clamping of the umbilical cord after birth may benefit some infants by preventing iron deficiency. Implications of delayed cord clamping for public cord blood banking remains unclear. CBUs collected by Canadian Blood Services at one collection site between November 1, 2014, and March 17, 2015, were analyzed. The delay in cord clamping after birth was timed and classified as "no delay," 20 to 60 seconds, more than 60 seconds, or more than 120 seconds. Of 367 collections, 100 reported no delay in clamping while clamping was delayed by 20 to 60 seconds (n = 69), more than 60 seconds (n = 98), or more than 120 seconds (n = 100) in the remaining cases. The mean volume and total nucleated cells (TNCs) in units with no delay in clamping were significantly greater than mean volumes for all categories of delayed clamping (Tukey's test, p < 0.05 for each comparison). The proportion of units with more than 1.5 × 10(9) TNCs was significantly reduced when clamping was delayed (p = 5.5 × 10(-8) ). The difference was most marked for cords that were clamped more than 120 seconds after delivery (6.2% compared with 39%). Delayed cord clamping greatly diminishes the volume and TNC count of units collected for a public cord blood bank. Creating an inventory of CBUs with high TNC content may take more time than expected. © 2015 AABB.
Kovac, Jason R; Luke, Patrick P
2010-01-01
Excision of renal cell carcinoma (RCC) with corresponding vena cava thrombus is a technical challenge requiring open resection and vascular clamping. A 58 year old male with a right kidney tumor presented with a thrombus extending 1 cm into the vena cava. Using a hand-assisted transperitoneal approach through a 7 cm gel-port, the right kidney was dissected and the multiple vascular collaterals supplying the tumor were identified and isolated. The inferior vena cava was mobilized 4 cm cephalad and 4 cm caudal to the right renal vein. Lateral manual traction was applied to the right kidney allowing the tumor thrombus to be retracted into the renal vein, clear of the vena cava. After laparoscopic ultrasonographic confirmation of the location of the tip of the tumor thrombus, an articulating laparoscopic vascular stapler was used to staple the vena cava at the ostium of the right renal vein. This allowed removal of the tumor thrombus without the need for a Satinsky clamp. The surgery was completed in 243 minutes with no intra-operative complications. The entire kidney and tumor thrombus was removed with negative surgical margins. Estimated blood loss was 300 cc. We present a laparoscopic resection of a renal mass with associated level II thrombus using a hand-assisted approach. In patients with minimal caval involvement, our surgical approach presents an option to the traditional open resection of a renal mass.
Palestro, Pablo; Enrique, Nicolas; Goicoechea, Sofia; Villalba, María Luisa; Sabatier, Laureano Leonel; Martin, Pedro; Milesi, Veronica; Bruno-Blanch, Luis E; Gavernet, Luciana
2018-06-05
The purpose of this investigation is to contribute to the development of new anticonvulsant drugs to treat patients with refractory epilepsy. We applied a virtual screening protocol that involved the search into molecular databases of new compounds and known drugs to find small molecules that interact with the open conformation of the Nav1.2 pore. As the 3D structure of human Nav1.2 is not available, we first assembled 3D models of the target, in closed and open conformations. After the virtual screening, the resulting candidates were submitted to a second virtual filter, to find compounds with better chances of being effective for the treatment of P-glycoprotein (P-gp) mediated resistant epilepsy. Again, we built a model of the 3D structure of human P-gp and we validated the docking methodology selected to propose the best candidates, which were experimentally tested on Nav1.2 channels by patch clamp techniques and in vivo by MES-test. Patch clamp studies allowed us to corroborate that our candidates, drugs used for the treatment of other pathologies like Ciprofloxacin, Losartan and Valsartan, exhibit inhibitory effects on Nav1.2 channel activity. Additionally, a compound synthesized in our lab, N,N´-diphenethylsulfamide, interacts with the target and also triggers significant Na1.2 channel inhibitory action. Finally, in-vivo studies confirmed the anticonvulsant action of Valsartan, Ciprofloxacin and N.N´-diphenethylsulfamide.
30 CFR 75.605 - Clamping of trailing cables to equipment.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clamping of trailing cables to equipment. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.605 Clamping of trailing cables to equipment. [Statutory Provisions] Trailing cables shall be clamped to...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-07
...-steer loaders are four-wheel drive vehicles with the left-side drive wheels independent of the right... exporter can demonstrate that it is sufficiently independent so as to be entitled to a separate rate.\\28... separate rate analysis is not necessary to determine whether it is independent from government control.\\29...
Environmental Assessment: Anti-Terrorism/Force Protection McConnell Air Force Base, Kansas
2003-09-01
handled, stored, transported, disposed, or recycled in accordance with these regulations. The potential for hazardous waste generation from gate...Loader (rubber tire) Concrete Truck Concrete Finisher Crane Asphalt Spreader Roller Flat Bed Truck (18 wheel) Scraper Trenching Machine 1...plastics, and lumber. These materials would be placed in the appropriate construction materials landfill or recycled when possible. These wastes
The Weak Link HP-41C hand-held calculator program
Ross A. Phillips; Penn A. Peters; Gary D. Falk
1982-01-01
The Weak Link hand-held calculator program (HP-41C) quickly analyzes a system for logging production and costs. The production equations model conventional chain saw, skidder, loader, and tandemaxle truck operations in eastern mountain areas. Production of each function of the logging system may be determined so that the system may be balanced for minimum cost. The...
Comparison of two thinning systems. Part 1. Stand and site impacts
Bobby L. Lanford; Bryce J. Stokes
1995-01-01
During the winter of 1991, a side-by-side comparison was made between two popular thinning systems:a feller-buncher, grapple skidder, loader/slasher system and a harvester, forwarder system. A first commercial thinning was conducted in an 18-year-old loblolly pine stand Test areas were cruised prior to thinning and remeasured after operations were completed The target...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ruff, T.M.
1992-01-01
A prototype mucking machine designed to operate in narrow vein stopes was developed by Foster-Miller, Inc., Waltham, MA, under contract with the U.S. Bureau of Mines. The machine, called a compact loader/trammer, or minimucker, was designed to replace slusher muckers in narrow-vein underground mines. The minimucker is a six-wheel-drive, skid-steered, load-haul-dump machine that loads muck at the front with a novel slide-bucket system and ejects it out the rear so that the machine does not have to be turned around. To correct deficiencies of the tether remote control system, a computer-based, radio remote control was retrofitted to the minimucker. Initialmore » tests indicated a need to assist the operator in guiding the machine in narrow stopes and an automatic guidance system that used ultrasonic ranging sensors and a wall-following algorithm was installed. Additional tests in a simulated test stope showed that these changes improved the operation of the minimucker. The design and functions of the minimucker and its computer-based, remote control system are reviewed, and an ultrasonic, sensor-based guidance system is described.« less
Development of the Los Alamos National Laboratory Cryogenic Pressure Loader
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ebey, Peter S.; Dole, James M.; Hoffer, James K.
2003-05-15
Targets for inertial fusion research and ignition at OMEGA, the National Ignition Facility, LMJ, and future facilities rely on beta-radiation-driven layering of spherical cryogenic DT ice layers contained within plastic or metal shells. Plastic shells will be permeation filled at room temperature then cooled to cryogenic temperatures before removal of the overpressure. The cryogenic pressure loader (CPL) was recently developed at Los Alamos National Laboratory as a testbed for studying the filling and layering of plastic target shells with DT. A technical description of the CPL is provided. The CPL consists of a cryostat, which contains a high-pressure permeation cell,more » and has optical access for investigating beta layering. The cryostat is housed within a tritium glovebox that contains manifolds for supplying high-pressure DT. The CPL shares some design elements with the cryogenic target handling system at the OMEGA facility to allow testing of tritium issues related to that system. The CPL has the capability to fill plastic targets by permeation to pressures up to 100 MPa and to cool them to 15 K. The CPL will accommodate a range of targets and may be modified for future experiments.« less
Ayling, Pete; Hill, Robert; Jassam, Nuthar; Kallner, Anders; Khatami, Zahra
2017-11-01
Background A logical consequence of the introduction of robotics and high-capacity analysers has seen a consolidation to larger units. This requires new structures and quality systems to ensure that laboratories deliver consistent and comparable results. Methods A spreadsheet program was designed to accommodate results from up to 12 different instruments/laboratories and present IQC data, i.e. Levey-Jennings and Youden plots and comprehensive numerical tables of the performance of each item. Input of data was made possible by a 'data loader' by which IQC data from the individual instruments could be transferred to the spreadsheet program on line. Results A set of real data from laboratories is used to populate the data loader and the networking software program. Examples are present from the analysis of variance components, the Levey-Jennings and Youden plots. Conclusions This report presents a software package that allows the simultaneous management and detailed monitoring of the performance of up to 12 different instruments/laboratories in a fully interactive mode. The system allows a quality manager of networked laboratories to have a continuous updated overview of the performance. This software package has been made available at the ACB website.
Environmental and economic analyses of waste disposal options for traditional markets in Indonesia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aye, Lu; Widjaya, E.R.
2006-07-01
Waste from traditional markets in Indonesia is the second largest stream of municipal solid waste after household waste. It has a higher organic fraction and may have greater potential to be managed on a business scale compared to household wastes. The attributed reason is that in general the wastes generated from traditional markets are more uniform, more concentrated and less hazardous than waste from other sources. This paper presents the results of environmental and economic assessments to compare the options available for traditional market waste disposal in Indonesia. The options compared were composting in labour intensive plants, composting in amore » centralised plant that utilised a simple wheel loader, centralised biogas production and landfill for electricity production. The current open dumping practice was included as the baseline case. A life cycle assessment (LCA) was used for environmental analysis. All options compared have lower environmental impacts than the current practice of open dumping. The biogas production option has the lowest environmental impacts. A cost-benefit analysis, which considered greenhouse gas savings, was used for the economic assessment. It was found that composting at a centralised plant is the most economically feasible option under the present Indonesian conditions. The approach reported in this study could be applied for 'a pre-feasibility first cut comparison' that includes environmental aspects in a decision-making framework for developing countries even though European emission factors were used.« less
Wettwer, Erich; Himmel, Herbert M; Amos, Gregory J; Li, Qi; Metzger, Franz; Ravens, Ursula
1998-01-01
Tedisamil is a new antiarrhythmic drug with predominant class III action. The aim of the present study was to investigate the blocking pattern of the compound on the transient outward current (Ito) in human subepicardial myocytes isolated from explanted left ventricles. Using the single electrode whole cell voltage clamp technique, Ito was analysed after appropriate voltage inactivation of sodium current and block of calcium current.Tedisamil reduced the amplitude of peak Ito, but did not affect the amplitude of non-inactivating outward current. The drug accelerated the apparent rate of Ito inactivation. The reduction in time constant of Ito inactivation depended on drug concentration, the apparent IC50 value was 4.4 μM.Tedisamil affected Ito amplitude in a use-dependent manner. After 2 min at −80 mV, maximum block of Ito was reached after 4–5 clamp steps either at the frequency of 0.2 or 2 Hz, indicating that the block was not frequency-dependent in an experimentally relevant range. Recovery from block was very slow and proceeded with a time constant of 12.1±1.8 s. Also in the presence of drug, a fraction of channels recovered from inactivation with a similar time constant as in control myocytes (i.e. 81±40 ms and 51±8 ms, respectively, n.s.).From the onset of fractional block of Ito by tedisamil during the initial 60 ms of a clamp step, we calculated k1=9×106 mol−1 s−1 for the association rate constant, and k2=23 s−1 for the dissociation rate constant. The resulting apparent KD was 2.6 μM and is similar to the IC50 value.The effects of tedisamil on Ito could be simulated by assuming a four state channel model where the drug binds to the channel in an open (activated) conformation. It is concluded that in human subepicardial myocytes tedisamil is an open channel blocker of Ito and that this effect probably contributes to the antiarrhythmic potential of this drug. PMID:9831899
Mechanical support of a ceramic gas turbine vane ring
Shi, Jun; Green, Kevin E.; Mosher, Daniel A.; Holowczak, John E.; Reinhardt, Gregory E.
2010-07-27
An assembly for mounting a ceramic turbine vane ring onto a turbine support casing comprises a first metal clamping ring and a second metal clamping ring. The first metal clamping ring is configured to engage with a first side of a tab member of the ceramic turbine vane ring. The second metal clamping ring is configured to engage with a second side of the tab member such that the tab member is disposed between the first and second metal clamping rings.
Active energy recovery clamping circuit to improve the performance of power converters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Whitaker, Bret; Barkley, Adam
2017-05-09
A regenerative clamping circuit for a power converter using clamping diodes to transfer charge to a clamping capacitor and a regenerative converter to transfer charge out of the clamping capacitor back to the power supply input connection. The regenerative converter uses a switch connected to the midpoint of a series connected inductor and capacitor. The ends of the inductor and capacitor series are connected across the terminals of the power supply to be in parallel with the power supply.
NASA Technical Reports Server (NTRS)
Young, Ken (Inventor); Hindle, Timothy (Inventor)
2014-01-01
A payload launch lock mechanism includes a base, a preload clamp, a fastener, and a shape memory alloy (SMA) actuator. The preload clamp is configured to releasibly restrain a payload. The fastener extends, along an axis, through the preload clamp and into the base, and supplies a force to the preload clamp sufficient to restrain the payload. The SMA actuator is disposed between the base and the clamp. The SMA actuator is adapted to receive electrical current and is configured, upon receipt of the electrical current, to supply a force that causes the fastener to elongate without fracturing. The preload clamp, in response to the fastener elongation, either rotates or pivots to thereby release the payload.
21 CFR 876.5160 - Urological clamp for males.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Urological clamp for males. 876.5160 Section 876...) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5160 Urological clamp for males. (a) Identification. A urological clamp for males is a device used to close the urethra of a male to...
Experimental Modal Analysis of Rectangular and Circular Beams
ERIC Educational Resources Information Center
Emory, Benjamin H.; Zhu, Wei Dong
2006-01-01
Analytical and experimental methods are used to determine the natural frequencies and mode shapes of Aluminum 6061-T651 beams with rectangular and circular cross-sections. A unique test stand is developed to provide the rectangular beam with different boundary conditions including clamped-free, clamped-clamped, clamped-pinned, and pinned-pinned.…
Solutions for transients in arbitrarily branching cables: III. Voltage clamp problems.
Major, G
1993-07-01
Branched cable voltage recording and voltage clamp analytical solutions derived in two previous papers are used to explore practical issues concerning voltage clamp. Single exponentials can be fitted reasonably well to the decay phase of clamped synaptic currents, although they contain many underlying components. The effective time constant depends on the fit interval. The smoothing effects on synaptic clamp currents of dendritic cables and series resistance are explored with a single cylinder + soma model, for inputs with different time courses. "Soma" and "cable" charging currents cannot be separated easily when the soma is much smaller than the dendrites. Subtractive soma capacitance compensation and series resistance compensation are discussed. In a hippocampal CA1 pyramidal neurone model, voltage control at most dendritic sites is extremely poor. Parameter dependencies are illustrated. The effects of series resistance compound those of dendritic cables and depend on the "effective capacitance" of the cell. Plausible combinations of parameters can cause order-of-magnitude distortions to clamp current waveform measures of simulated Schaeffer collateral inputs. These voltage clamp problems are unlikely to be solved by the use of switch clamp methods.
Dynamic analysis of clamp band joint system subjected to axial vibration
NASA Astrophysics Data System (ADS)
Qin, Z. Y.; Yan, S. Z.; Chu, F. L.
2010-10-01
Clamp band joints are commonly used for connecting circular components together in industry. Some of the systems jointed by clamp band are subjected to dynamic load. However, very little research on the dynamic characteristics for this kind of joint can be found in the literature. In this paper, a dynamic model for clamp band joint system is developed. Contact and frictional slip between the components are accommodated in this model. Nonlinear finite element analysis is conducted to identify the model parameters. Then static experiments are carried out on a scaled model of the clamp band joint to validate the joint model. Finally, the model is adopted to study the dynamic characteristics of the clamp band joint system subjected to axial harmonic excitation and the effects of the wedge angle of the clamp band joint and the preload on the response. The model proposed in this paper can represent the nonlinearity of the clamp band joint and be used conveniently to investigate the effects of the structural and loading parameters on the dynamic characteristics of this type of joint system.
Gómez-González, J F; Destexhe, A; Bal, T
2014-10-01
Electrophysiological recordings of single neurons in brain tissues are very common in neuroscience. Glass microelectrodes filled with an electrolyte are used to impale the cell membrane in order to record the membrane potential or to inject current. Their high resistance induces a high voltage drop when passing current and it is essential to correct the voltage measurements. In particular, for voltage clamping, the traditional alternatives are two-electrode voltage-clamp technique or discontinuous single electrode voltage-clamp (dSEVC). Nevertheless, it is generally difficult to impale two electrodes in a same neuron and the switching frequency is limited to low frequencies in the case of dSEVC. We present a novel fully computer-implemented alternative to perform continuous voltage-clamp recordings with a single sharp-electrode. To reach such voltage-clamp recordings, we combine an active electrode compensation algorithm (AEC) with a digital controller (AECVC). We applied two types of control-systems: a linear controller (proportional plus integrative controller) and a model-based controller (optimal control). We compared the performance of the two methods to dSEVC using a dynamic model cell and experiments in brain slices. The AECVC method provides an entirely digital method to perform continuous recording and smooth switching between voltage-clamp, current clamp or dynamic-clamp configurations without introducing artifacts.
Schlosser, O; Huyard, A; Rybacki, D; Do Quang, Z
2012-06-01
Microbial quality of air inside vehicle cabs is a major occupational health risk management issue in composting facilities. Large differences and discrepancies in protection factors between vehicles and between biological agents have been reported. This study aimed at estimating the mean protection efficiency of the vehicle cab environment against bioaerosols with higher precision. In-cab measurement results were also analysed to ascertain whether or not these protection systems reduce workers' exposure to tolerable levels. Five front-end loaders, one mobile mixer and two agricultural tractors pulling windrow turners were investigated. Four vehicles were fitted with a pressurisation and high efficiency particulate air (HEPA) filtration system. The four others were only equipped with pleated paper filter without pressurisation. Bacteria, fungi and endotoxins were measured in 72 pairs of air samples, simultaneously collected inside the cab and on the outside of the cab with a CIP 10-M sampler. A front-end loader, purchased a few weeks previously, fitted with a pressurisation and high efficiency particulate air (HEPA) filtration system, and with a clean cab, exhibited a mean protection efficiency of between 99.47% CI 95% [98.58-99.97%] and 99.91% [99.78-99.98%] depending on the biological agent. It is likely that the lower protection efficiency demonstrated in other vehicles was caused by penetration through the only moderately efficient filters, by the absence of pressurisation, by leakage in the filter-sealing system, and by re-suspension of particles which accumulated in dirty cabs. Mean protection efficiency in regards to bacteria and endotoxins ranged between 92.64% [81.87-97.89%] and 98.61% [97.41-99.38%], and between 92.68% [88.11-96.08%] and 98.43% [97.44-99.22%], respectively. The mean protection efficiency was the lowest when confronted with fungal spores, from 59.76% [4.19-90.75%] to 94.71% [91.07-97.37%]. The probability that in-cab exposure to fungi exceeded the benchmark value for short-term respiratory effects suggests that front-end loaders and mobile mixers in composting facilities should be fitted with a pressurisation and HEPA filtration system, regardless of whether or not the facility is indoors or outdoors. Regarding the tractors, exposure inside the cabs was not significantly reduced. However, in this study, there was a less than 0.01% risk of exceeding the bench mark value associated with fungi related short-term respiratory effects during an 1-h per day windrow turning operation. Pressurisation and a HEPA filtration system can provide safe working conditions inside loaders and mobile mixer with regard to airborne bacteria, fungi and endotoxins in composting facilities. However, regular thorough cleaning of the vehicle cab, as well as overalls and shoes cleaning, and mitigation of leakage in the filter-sealing system are necessary to achieve high levels of protection efficiency. Copyright © 2012 Elsevier Ltd. All rights reserved.
2010-11-08
celiac aortic clamping (n=6), direct vascular control (n=6), and endovascular aortic occlusion n=6). This study presents a large animal model of class...including thoracic aortic clamping, supra- celiac aortic clamping, direct vascular control, and proximal endovascular balloon occlusion. Following vascular...subsequently underwent non-compressible hemorrhage with thoracic aortic clamping (n=6), supra- celiac aortic clamping (n=6), direct vascular control (n=6
Attebery, H. R.; Finegold, S. M.
1969-01-01
A double-closured method introduced for Hungate tubes eliminates clamps or special racks to hold the rubber stoppers in place while the tubes are being processed. The system prevents stoppers from being dislodged by gas-producing anaerobes and keeps the stoppers sterile so that the closed system of transfer can be conveniently utilized. Open and closed systems for handling a gas-producing anaerobe were compared. Ten tubes containing Clostridium perfringens were opened; the organism was detected in the air by use of an impingement collector. The gloved hand of the operator also revealed the test organism. A similar trial with culture material removed by the closed system (syringe transfer) resulted in no detectable contamination of the environment. Images PMID:4312921
Attebery, H R; Finegold, S M
1969-10-01
A double-closured method introduced for Hungate tubes eliminates clamps or special racks to hold the rubber stoppers in place while the tubes are being processed. The system prevents stoppers from being dislodged by gas-producing anaerobes and keeps the stoppers sterile so that the closed system of transfer can be conveniently utilized. Open and closed systems for handling a gas-producing anaerobe were compared. Ten tubes containing Clostridium perfringens were opened; the organism was detected in the air by use of an impingement collector. The gloved hand of the operator also revealed the test organism. A similar trial with culture material removed by the closed system (syringe transfer) resulted in no detectable contamination of the environment.
Core-coat conductor of lipid bilayer and micromachined silicon.
Fromherz, P; Klingler, J
1991-02-11
We have etched a groove into a (110) plane of silicon and have covered it with a bilayer of glycerol monooleate. We have varied the depth of the groove, the concentration of salt in the electrolyte and the density of gramicidin in the membrane. We have clamped one end of the groove at a constant voltage with respect to the bath keeping the other end sealed or electrically open with respect to the bath. We have measured (i) the voltage at the center of the groove and at the sealed distal end and (ii) the current through the system in sealed and open configuration. We have found that the spread of voltage is in quantitative agreement with the stationary solutions of Kelvin's equation for a homogeneous cable.
Na+ current in presynaptic terminals of the crayfish opener cannot initiate action potentials.
Lin, Jen-Wei
2016-01-01
Action potential (AP) propagation in presynaptic axons of the crayfish opener neuromuscular junction (NMJ) was investigated by simultaneously recording from a terminal varicosity and a proximal branch. Although orthodromically conducting APs could be recorded in terminals with amplitudes up to 70 mV, depolarizing steps in terminals to -20 mV or higher failed to fire APs. Patch-clamp recordings did detect Na(+) current (INa) in most terminals. The INa exhibited a high threshold and fast activation rate. Local perfusion of Na(+)-free saline showed that terminal INa contributed to AP waveform by slightly accelerating the rising phase and increasing the peak amplitude. These findings suggest that terminal INa functions to "touch up" but not to generate APs. Copyright © 2016 the American Physiological Society.
Sigworth, F J
1985-05-01
The random passage of ions through an open channel is expected to result in shot noise fluctuations in the channel current. The patch-clamp technique now allows fluctuations of this size to be observed in single-channel currents. In the experiments reported here the acetylcholine-induced currents in cultured rat muscle cells were analyzed; fluctuations were found that were considerably larger than expected for shot noise. A low-frequency component, which was fitted with a Lorentzian, was examined in detail; it appears to arise from fluctuations in channel conductance of approximately 3% on a time scale of 1 ms. The characteristic relaxation time is voltage dependent and temperature dependent (Q10 approximately equal to 3) suggesting that the fluctuations arise from conformational fluctuations in the channel protein.
Pierce, Eric T; Kumar, Vikram; Zheng, Hui; Peterfreund, Robert A
2013-03-01
Gravity-driven micro-drip infusion sets allow control of medication dose delivery by adjusting drops per minute. When the roller clamp is fully open, flow in the drip chamber can be a continuous fluid column rather than discrete, countable, drops. We hypothesized that during this "wide-open" state, drug delivery becomes dependent on factors extrinsic to the micro-drip set and is therefore difficult to predict. We conducted laboratory experiments to characterize volume delivery under various clinically relevant conditions of wide-open flow in an in vitro laboratory model. A micro-drip infusion set, plugged into a bag of normal saline, was connected to a high-flow stopcock at the distal end. Vertically oriented IV catheters (gauges 14-22) were connected to the stopcock. The fluid meniscus height in the bag was fixed (60-120 cm) above the outflow point. The roller clamp on the infusion set was in fully open position for all experiments resulting in a continuous column of fluid in the drip chamber. Fluid volume delivered in 1 minute was measured 4 times with each condition. To model resistive effects of carrier flow, volumetric infusion pumps were used to deliver various flow rates of normal saline through a carrier IV set into which a micro-drip infusion was "piggybacked." We also compared delivery by micro-drip infusion sets from 3 manufacturers. The volume of fluid delivered by gravity-driven infusion under wide-open conditions (continuous fluid column in drip chamber) varied 2.9-fold (95% confidence interval, 2.84-2.96) depending on catheter size and fluid column height. Total model resistance of the micro-drip with stopcock and catheter varied with flow rate. Volume delivered by the piggybacked micro-drip decreased up to 29.7% ± 0.8% (mean ± SE) as the carrier flow increased from 0 to 1998 mL/min. Delivery characteristics of the micro-drip infusion sets from 3 different manufacturers were similar. Laboratory simulation of clinical situations with gravity-driven micro-drip infusion sets under wide-open flow conditions revealed that infusion rate (drug and/or volume delivery) can vary widely depending on extrinsic factors including catheter size, fluid column height, and carrier flow. The variable resistance implies nonlaminar flow in the micro-drip model that cannot be easily predicted mathematically. These findings support the use of mechanical pumps instead of gravity-driven micro-drips to enhance the precision and safety of IV infusions, especially for vasoactive drugs.
Mini-invasive aortic surgery: personal experience.
Spinelli, Francesco; Stilo, Francesco; La Spada, Michele; Benedetto, Filippo; De Caridi, Giovanni; Barillà, David; Giardina, Massimiliano; David, Antonio
2014-01-01
In this study, we retrospectively evaluated our experience in minilaparotomy (MINI) and compared the results with conventional open repair (OPEN). From January 2005 to December 2012, we surgically treated 234 consecutive patients with elective infrarenal abdominal aortic aneurysms, 195 men and 39 women, with a mean age of 74 years. Inclusion criteria for MINI were not ruptured abdominal aortic aneurysm, increased surgical risk, anatomical limits for endovascular repair, no previous surgical invasion of the abdominal cavity, and no requirement for concomitant abdominal surgical invasion. Surgical treatment was OPEN in 113 patients (48.3%) and MINI through an 8- to 14-cm incision in 121 patients (51.7%). Epidural anesthesia has been added in 26.5% and in 19.3% of the MINI and OPEN patients, respectively. Mortality, complications, aortic clamping time, operative time, need for postoperative morphine therapy, time to solid diet, and length of hospital stay were registered. The MINI has been performed in all patients selected, with 72 aortoaortic grafts and 49 aortobisiliac grafts. Early mortality was 1.6% versus 3.5% (P > 0.5); 1-, 3-, and 5-year mortality were 7% versus 9%, 19% versus 22%, and 29% versus 34% (P > 0.5); complications were 12.2% versus 26.6% (P > 0.05); mean (SD) clamping time was 48 (12) versus 44 (14) minutes (P > 0.5); mean (SD) operative time was 218.72 (41.95) versus 191.44 (21.73) minutes (P > 0.025); mean (SD) estimated intraoperative blood loss was 425.64 (85.95) versus 385.30 (72.41) mL (P > 0.1); mean (SD) morphine consumption in the group given epidural and the group not given epidural was 0 (2) and 2 (2) mg intravenously (IV) versus 2 (4) (P < 0.5) and 4 (3) mg IV (P > 0.1); mean (SD) ambulation was 2.1 (0.6) versus 4.1 (2.7) (P < 0.5); mean (SD) time to solid diet was 2.1 (0.4) versus 3.5 (1.6) (P < 0.5); and mean (SD) length of hospital stay was 4.9 (1.64) versus 7.35 (1.95) days (P > 0.05), in the MINI and OPEN groups, respectively. Postoperative hernia at 3 years was 18% versus 23% in the MINI and OPEN groups (P < 0.5), respectively. The MINI gives the patients a significantly shorter period of recovery with the quality and safety of the OPEN. This experience suggested extending the indication to all surgical candidates without local limitations.
24. BUILDING NO. 452, ORDNANCE FACILITY (BAG CHARGE FILLING PLANT), ...
24. BUILDING NO. 452, ORDNANCE FACILITY (BAG CHARGE FILLING PLANT), INTERIOR VIEW LOOKING WEST AT NORTH END OF CENTRAL CORRIDOR (ROOM 3). STAIRWAY WORKBENCH WITH COMPRESSED-AIR POWERED CARTRIDGE LOADER. ARMORED PASS-THROUGH OF TRANSFER BOX FOR PASSING EXPLOSIVES MATERIALS THROUGH TO NEXT ROOM TO THE NORTH. - Picatinny Arsenal, 400 Area, Gun Bag Loading District, State Route 15 near I-80, Dover, Morris County, NJ
ERIC Educational Resources Information Center
Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.
The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…
Code of Federal Regulations, 2012 CFR
2012-07-01
... parte Nos. MC-2 and MC-3, 28 M.C.C. 125, 133, 134, 139), is an employee of a carrier subject to section... U.S. 649; Pyramid Motor Freight Corp. v. Ispass, 330 U.S. 695; Walling v. Gordon's Transport (W.D...; Walling v. Huber & Huber Motor Express, 67 F. Supp. 855; Ex parte Nos. MC-2 and MC-3, 28 M.C.C. 125, 133...
Code of Federal Regulations, 2013 CFR
2013-07-01
... parte Nos. MC-2 and MC-3, 28 M.C.C. 125, 133, 134, 139), is an employee of a carrier subject to section... U.S. 649; Pyramid Motor Freight Corp. v. Ispass, 330 U.S. 695; Walling v. Gordon's Transport (W.D...; Walling v. Huber & Huber Motor Express, 67 F. Supp. 855; Ex parte Nos. MC-2 and MC-3, 28 M.C.C. 125, 133...
Code of Federal Regulations, 2014 CFR
2014-07-01
... parte Nos. MC-2 and MC-3, 28 M.C.C. 125, 133, 134, 139), is an employee of a carrier subject to section... U.S. 649; Pyramid Motor Freight Corp. v. Ispass, 330 U.S. 695; Walling v. Gordon's Transport (W.D...; Walling v. Huber & Huber Motor Express, 67 F. Supp. 855; Ex parte Nos. MC-2 and MC-3, 28 M.C.C. 125, 133...
NASA Technical Reports Server (NTRS)
Wade, Randall S.; Jones, Bailey
2009-01-01
A computer program loads configuration code into a Xilinx field-programmable gate array (FPGA), reads back and verifies that code, reloads the code if an error is detected, and monitors the performance of the FPGA for errors in the presence of radiation. The program consists mainly of a set of VHDL files (wherein "VHDL" signifies "VHSIC Hardware Description Language" and "VHSIC" signifies "very-high-speed integrated circuit").
A structural and mechanistic study of π-clamp-mediated cysteine perfluoroarylation.
Dai, Peng; Williams, Jonathan K; Zhang, Chi; Welborn, Matthew; Shepherd, James J; Zhu, Tianyu; Van Voorhis, Troy; Hong, Mei; Pentelute, Bradley L
2017-08-11
Natural enzymes use local environments to tune the reactivity of amino acid side chains. In searching for small peptides with similar properties, we discovered a four-residue π-clamp motif (Phe-Cys-Pro-Phe) for regio- and chemoselective arylation of cysteine in ribosomally produced proteins. Here we report mutational, computational, and structural findings directed toward elucidating the molecular factors that drive π-clamp-mediated arylation. We show the significance of a trans conformation prolyl amide bond for the π-clamp reactivity. The π-clamp cysteine arylation reaction enthalpy of activation (ΔH ‡ ) is significantly lower than a non-π-clamp cysteine. Solid-state NMR chemical shifts indicate the prolyl amide bond in the π-clamp motif adopts a 1:1 ratio of the cis and trans conformation, while in the reaction product Pro3 was exclusively in trans. In two structural models of the perfluoroarylated product, distinct interactions at 4.7 Å between Phe1 side chain and perfluoroaryl electrophile moiety are observed. Further, solution 19 F NMR and isothermal titration calorimetry measurements suggest interactions between hydrophobic side chains in a π-clamp mutant and the perfluoroaryl probe. These studies led us to design a π-clamp mutant with an 85-fold rate enhancement. These findings will guide us toward the discovery of small reactive peptides to facilitate abiotic chemistry in water.
Combination Space Station Handrail Clamp and Pointing Device
NASA Technical Reports Server (NTRS)
Hughes, Stephen J. (Inventor)
1999-01-01
A device for attaching an experiment carrier to a space station handrail is provided. The device has two major components, a clamping mechanism for attachment to a space station handrail, and a pointing carrier on which an experiment package can be mounted and oriented. The handrail clamp uses an overcenter mechanism and the carrier mechanism uses an adjustable preload ball and socket for carrier positioning. The handrail clamp uses a stack of disk springs to provide a spring loaded button. This configuration provides consistent clamping force over a range of possible handrail thicknesses. Three load points are incorporated in the clamping mechanism thereby spreading the clamping load onto three separate points on the handrail. A four bar linkage is used to provide for a single actuation lever for all three load points. For additional safety, a secondary lock consisting of a capture plate and push lock keeps the clamp attached to the handrail in the event of main clamp failure. For the carrier positioning mechanism, a ball in a spring loaded socket uses friction to provide locking torque; however. the ball and socket are torque limited so that the ball ran slip under kick loads (125 pounds or greater). A lead screw attached to disk spring stacks is used to provide an adjustable spring force on the socket. A locking knob is attached to the lead screw to allow for hand manipulation of the lead screw.
Cardiovascular transition at birth: a physiological sequence.
Hooper, Stuart B; Te Pas, Arjan B; Lang, Justin; van Vonderen, Jeroen J; Roehr, Charles Christoph; Kluckow, Martin; Gill, Andrew W; Wallace, Euan M; Polglase, Graeme R
2015-05-01
The transition to newborn life at birth involves major cardiovascular changes that are triggered by lung aeration. These include a large increase in pulmonary blood flow (PBF), which is required for pulmonary gas exchange and to replace umbilical venous return as the source of preload for the left heart. Clamping the umbilical cord before PBF increases reduces venous return and preload for the left heart and thereby reduces cardiac output. Thus, if ventilation onset is delayed following cord clamping, the infant is at risk of superimposing an ischemic insult, due to low cardiac output, on top of an asphyxic insult. Much debate has centered on the timing of cord clamping at birth, focusing mainly on the potential for a time-dependent placental to infant blood transfusion. This has prompted recommendations for delayed cord clamping for a set time after birth in infants not requiring resuscitation. However, recent evidence indicates that ventilation onset before cord clamping mitigates the adverse cardiovascular consequences caused by immediate cord clamping. This indicates that the timing of cord clamping should be based on the infant's physiology rather than an arbitrary period of time and that delayed cord clamping may be of greatest benefit to apneic infants.
Planar patch clamp for neuronal networks--considerations and future perspectives.
Bosca, Alessandro; Martina, Marzia; Py, Christophe
2014-01-01
The patch-clamp technique is generally accepted as the gold standard for studying ion channel activity allowing investigators to either "clamp" membrane voltage and directly measure transmembrane currents through ion channels, or to passively monitor spontaneously occurring intracellular voltage oscillations. However, this resulting high information content comes at a price. The technique is labor-intensive and requires highly trained personnel and expensive equipment. This seriously limits its application as an interrogation tool for drug development. Patch-clamp chips have been developed in the last decade to overcome the tedious manipulations associated with the use of glass pipettes in conventional patch-clamp experiments. In this chapter, we describe some of the main materials and fabrication protocols that have been developed to date for the production of patch-clamp chips. We also present the concept of a patch-clamp chip array providing high resolution patch-clamp recordings from individual cells at multiple sites in a network of communicating neurons. On this chip, the neurons are aligned with the aperture-probes using chemical patterning. In the discussion we review the potential use of this technology for pharmaceutical assays, neuronal physiology and synaptic plasticity studies.
Zhao, Hongwei; Fu, Lu; Ren, Luquan; Huang, Hu; Fan, Zunqiang; Li, Jianping; Qu, Han
2013-01-01
In this paper, a novel piezo-driven rotary actuator with the changeable clamping radius is developed based on the inchworm principle. This actuator mainly utilizes three piezoelectric actuators, a flexible gripper, a clamping block, and a rotor to achieve large stroke rotation with high resolution. The design process of the flexible gripper consisting of the driving unit and the clamping unit is described. Lever-type mechanisms were used to amplify the micro clamping displacements. The amplifying factor and parasitic displacement of the lever-type mechanism in the clamping unit was analyzed theoretically and experimentally. In order to investigate the rotation characteristics of the actuator, a series of experiments was carried out. Experimental results indicate that the actuator can rotate at a speed of 77,488 μrad/s with a driving frequency of 167 Hz. The rotation resolution and maximum load torque of the actuator are 0.25 μrad and 37 N mm, respectively. The gripper is movable along the z direction based on an elevating platform, and the clamping radius can change from 10.6 mm to 25 mm. Experimental results confirm that the actuator can achieve different rotation speeds by changing the clamping radius.
Clinical aspects of incorporating cord clamping into stabilisation of preterm infants.
Knol, Ronny; Brouwer, Emma; Vernooij, Alex S N; Klumper, Frans J C M; DeKoninck, Philip; Hooper, Stuart B; Te Pas, Arjan B
2018-04-21
Fetal to neonatal transition is characterised by major pulmonary and haemodynamic changes occurring in a short period of time. In the international neonatal resuscitation guidelines, comprehensive recommendations are available on supporting pulmonary transition and delaying clamping of the cord in preterm infants. Recent experimental studies demonstrated that the pulmonary and haemodynamic transition are intimately linked, could influence each other and that the timing of umbilical cord clamping should be incorporated into the respiratory stabilisation. We reviewed the current knowledge on how to incorporate cord clamping into stabilisation of preterm infants and the physiological-based cord clamping (PBCC) approach, with the infant's transitional status as key determinant of timing of cord clamping. This approach could result in optimal timing of cord clamping and has the potential to reduce major morbidities and mortality in preterm infants. © 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.
Zijlstra, Eric; Heinemann, Lutz; Fischer, Annelie; Kapitza, Christoph
2016-01-01
Background: The objective was to evaluate the performance (in terms of accuracy, precision, and trueness) of 5 CE-certified and commercially available blood glucose (BG) systems (meters plus test strips) using an innovative clinical-experimental study design with a 3-step glucose clamp approach and frequent capillary BG measurements. Methods: Sixteen subjects with type 1 diabetes participated in this open label, single center trial. BG was clamped at 3 levels for 60 minutes each: 60-100-200 mg/dL. Medical staff performed regular finger pricks (up to 10 per BG level) to obtain capillary blood samples for paired BG measurements with the 5 BG systems and a laboratory method as comparison. Results: Three BG systems displayed significantly lower mean absolute relative deviations (MARD) (ACCU-Chek® Aviva Nano [5.4%], BGStar® [5.1%], iBGStar® [5.3%]) than 2 others (FreeStyle InsuLinx® [7.7%], OneTouch Verio®IQ [10.3%]). The measurement precision of all BG systems was comparable, but relative bias was also lower for the 3 systems with lower MARD (ACCU-Chek [1.3%], BGStar [–0.9%], iBGStar [1.0%]) compared with the 2 others (FreeStyle [–7.2%], OneTouch [8.9%]). Conclusions: This 3 range glucose clamp approach enables a systematic performance evaluation of BG systems under controlled and reproducible conditions. The random error of the tested BG systems was comparable, but some showed a lower systematic error than others. These BG systems allow an accurate glucose measurement at low, normal and high BG levels. PMID:27605592
Zijlstra, Eric; Heinemann, Lutz; Fischer, Annelie; Kapitza, Christoph
2016-11-01
The objective was to evaluate the performance (in terms of accuracy, precision, and trueness) of 5 CE-certified and commercially available blood glucose (BG) systems (meters plus test strips) using an innovative clinical-experimental study design with a 3-step glucose clamp approach and frequent capillary BG measurements. Sixteen subjects with type 1 diabetes participated in this open label, single center trial. BG was clamped at 3 levels for 60 minutes each: 60-100-200 mg/dL. Medical staff performed regular finger pricks (up to 10 per BG level) to obtain capillary blood samples for paired BG measurements with the 5 BG systems and a laboratory method as comparison. Three BG systems displayed significantly lower mean absolute relative deviations (MARD) (ACCU-Chek® Aviva Nano [5.4%], BGStar® [5.1%], iBGStar® [5.3%]) than 2 others (FreeStyle InsuLinx® [7.7%], OneTouch Verio®IQ [10.3%]). The measurement precision of all BG systems was comparable, but relative bias was also lower for the 3 systems with lower MARD (ACCU-Chek [1.3%], BGStar [-0.9%], iBGStar [1.0%]) compared with the 2 others (FreeStyle [-7.2%], OneTouch [8.9%]). This 3 range glucose clamp approach enables a systematic performance evaluation of BG systems under controlled and reproducible conditions. The random error of the tested BG systems was comparable, but some showed a lower systematic error than others. These BG systems allow an accurate glucose measurement at low, normal and high BG levels. © 2016 Diabetes Technology Society.
Hristov, Kiril L.; Smith, Amy C.; Parajuli, Shankar P.; Malysz, John
2013-01-01
Large-conductance voltage- and Ca2+-activated K+ (BK) channels are critical regulators of detrusor smooth muscle (DSM) excitability and contractility. PKC modulates the contraction of DSM and BK channel activity in non-DSM cells; however, the cellular mechanism regulating the PKC-BK channel interaction in DSM remains unknown. We provide a novel mechanistic insight into BK channel regulation by PKC in DSM. We used patch-clamp electrophysiology, live-cell Ca2+ imaging, and functional studies of DSM contractility to elucidate BK channel regulation by PKC at cellular and tissue levels. Voltage-clamp experiments showed that pharmacological activation of PKC with PMA inhibited the spontaneous transient BK currents in native freshly isolated guinea pig DSM cells. Current-clamp recordings revealed that PMA significantly depolarized DSM membrane potential and inhibited the spontaneous transient hyperpolarizations in DSM cells. The PMA inhibitory effects on DSM membrane potential were completely abolished by the selective BK channel inhibitor paxilline. Activation of PKC with PMA did not affect the amplitude of the voltage-step-induced whole cell steady-state BK current or the single BK channel open probability (recorded in cell-attached mode) upon inhibition of all major Ca2+ sources for BK channel activation with thapsigargin, ryanodine, and nifedipine. PKC activation with PMA elevated intracellular Ca2+ levels in DSM cells and increased spontaneous phasic and nerve-evoked contractions of DSM isolated strips. Our results support the concept that PKC activation leads to a reduction of BK channel activity in DSM via a Ca2+-dependent mechanism, thus increasing DSM contractility. PMID:24352333
Double arch mirror study. Part 1: Preliminary engineering report
NASA Technical Reports Server (NTRS)
Vukobratovich, D.; Hillman, D.
1983-01-01
In the proposed design, the NASA AMES 20-in double arch mirror is supported by three clamp and flexure assemblies. The mirror clamp consists of a T-shaped Invar-36 member that goes into a similarly shaped socket in the back of the mirror. The mirror socket is made oversize and contacts the clamp only along the conical surface. The clamp is preloaded by a spring washer and pulls the mirror into contact with the flexure. The clamp is then inserted into the mirror socket through a cutout, is rotated 90 deg, and is then pinned in place. Loading conditions considered in socket design are discussed as well as stress in the socket and clamp. Flexure geometry and stress are examined as well as the effects of flexure error and of mirror cell error.
Benavides, G.L.; Burt, J.D.
1994-07-12
The invention relates to a clamp mechanism that can be used to attach or temporarily support objects inside of tubular goods. The clamp mechanism can also be modified so that it grips objects. The clamp has a self-centering feature to accommodate out-of-roundness or other internal defections in tubular objects such as pipe. A plurality of clamping shoes are expanded by a linkage which is preferably powered by a motor to contact the inside of a pipe. The motion can be reversed and jaw elements can be connected to the linkage so as to bring the jaws together to grab an object. 12 figs.
Benavides, Gilbert L.; Burt, Jack D.
1994-01-01
The invention relates to a clamp mechanism that can be used to attach or temporarily support objects inside of tubular goods. The clamp mechanism can also be modified so that it grips objects. The clamp has a self-centering feature to accommodate out-of-roundness or other internal defections in tubular objects such as pipe. A plurality of clamping shoes are expanded by a linkage which is preferably powered by a motor to contact the inside of a pipe. The motion can be reversed and jaw elements can be connected to the linkage so as to bring the jaws together to grab an object.
Advanced motor driven clamped borehole seismic receiver
Engler, Bruce P.; Sleefe, Gerard E.; Striker, Richard P.
1993-01-01
A borehole seismic tool including a borehole clamp which only moves perpendicular to the borehole. The clamp is driven by an electric motor, via a right angle drive. When used as a seismic receiver, the tool has a three part housing, two of which are hermetically sealed. Accelerometers or geophones are mounted in one hermetically sealed part, the electric meter in the other hermetically sealed part, and the clamp and right angle drive in the third part. Preferably the tool includes cable connectors at both ends. Optionally a shear plate can be added to the clamp to extend the range of the tool.
Smith, Karl H.
2002-01-01
A radial wedge flange clamp comprising a pair of flanges each comprising a plurality of peripheral flat wedge facets having flat wedge surfaces and opposed and mating flat surfaces attached to or otherwise engaged with two elements to be joined and including a series of generally U-shaped wedge clamps each having flat wedge interior surfaces and engaging one pair of said peripheral flat wedge facets. Each of said generally U-shaped wedge clamps has in its opposing extremities apertures for the tangential insertion of bolts to apply uniform radial force to said wedge clamps when assembled about said wedge segments.
Wohl, P; Krusinová, E; Klementová, M; Wohl, P; Kratochvílová, S; Pelikánová, T
2008-01-01
The hyperinsulinemic euglycemic clamp (HEC) combined with indirect calorimetry (IC) is used for estimation of insulin-stimulated substrate utilization. Calculations are based on urinary urea nitrogen excretion (UE), which is influenced by correct urine collection. The aims of our study were to improve the timing of urine collection during the clamp and to test the effect of insulin on UE in patients with type 1 diabetes (DM1; n=11) and healthy subjects (C; n=11). Urine samples were collected (a) over 24 h divided into 3-h periods and (b) before and during two-step clamp (1 and 10 mIU.kg(-1).min(-1); period 1 and period 2) combined with IC. The UE during the clamp was corrected for changes in urea pool size (UEc). There were no significant differences in 24-h UE between C and DM1 and no circadian variation in UE in either group. During the clamp, serum urea decreased significantly in both groups (p<0.01). Therefore, UEc was significantly lower as compared to UE not adjusted for changes in urea pool size both in C (p<0.001) and DM1 (p<0.001). While UE did not change during the clamp, UEc decreased significantly in both groups (p<0.01). UEc during the clamp was significantly higher in DM1 compared to C both in period 1 (p<0.05) and period 2 (p<0.01). The UE over 24 h and UEc during the clamp were statistically different in both C and DM1. We conclude that urine collection performed during the clamp with UE adjusted for changes in urea pool size is the most suitable technique for measuring substrate utilization during the clamp both in DM1 and C. Urine collections during the clamp cannot be replaced either by 24-h sampling (periods I-VII) or by a single 24-h urine collection. Attenuated insulin-induced decrease in UEc in DM1 implicates the impaired insulin effect on proteolysis.
Zhang, Yan; Zhang, Jun-Wei; Wang, Bao-Hua
2017-06-01
Perioperative blood loss is still an unsolved problem in total knee arthroplasty (TKA). The efficacy of the preoperative use of tranexamic acid (TXA) plus drain-clamping to reduce blood loss in TKA has been debated. This meta-analysis aimed to illustrate the efficacy of TXA plus drain-clamping to reduce blood loss in patients who underwent a TKA. In February 2017, a systematic computer-based search was conducted in PubMed, EMBASE, Web of Science, the Cochrane Database of Systematic Reviews, and Google Scholar. Data from patients prepared for TKA in studies that compared TXA plus drain-clamping versus TXA alone, drain-clamping alone, or controls were retrieved. The primary endpoint was the need for transfusion. The secondary outcomes were total blood loss, blood loss in drainage, the decrease in hemoglobin, and the occurrence of deep venous thrombosis. After testing for publication bias and heterogeneity between studies, data were aggregated for random-effects models when necessary. Ultimately, 5 clinical studies with 618 patients (TXA plus drain-clamping group = 249, control group = 130, TXA-alone group = 60, and drain-clamping group = 179) were included. TXA plus drain-clamping could decrease the need for transfusion, total blood loss, blood loss in drainage, and the decrease in hemoglobin than could the control group, the TXA-alone group, and the drain-clamping group (P < .05). There was no significant difference between the occurrence of deep venous thrombosis between the included groups (P > .05). TXA plus drain-clamping can achieve the maximum effects of hemostasis in patients prepared for primary TKA. Because the number and the quality of the included studies were limited, more high-quality randomized controlled trials are needed to identify the optimal dose of TXA and the clamping hours in patients prepared for TKA.
Efficacy of tranexamic acid plus drain-clamping to reduce blood loss in total knee arthroplasty
Zhang, Yan; Zhang, Jun-Wei; Wang, Bao-Hua
2017-01-01
Abstract Background: Perioperative blood loss is still an unsolved problem in total knee arthroplasty (TKA). The efficacy of the preoperative use of tranexamic acid (TXA) plus drain-clamping to reduce blood loss in TKA has been debated. This meta-analysis aimed to illustrate the efficacy of TXA plus drain-clamping to reduce blood loss in patients who underwent a TKA. Methods: In February 2017, a systematic computer-based search was conducted in PubMed, EMBASE, Web of Science, the Cochrane Database of Systematic Reviews, and Google Scholar. Data from patients prepared for TKA in studies that compared TXA plus drain-clamping versus TXA alone, drain-clamping alone, or controls were retrieved. The primary endpoint was the need for transfusion. The secondary outcomes were total blood loss, blood loss in drainage, the decrease in hemoglobin, and the occurrence of deep venous thrombosis. After testing for publication bias and heterogeneity between studies, data were aggregated for random-effects models when necessary. Results: Ultimately, 5 clinical studies with 618 patients (TXA plus drain-clamping group = 249, control group = 130, TXA-alone group = 60, and drain-clamping group = 179) were included. TXA plus drain-clamping could decrease the need for transfusion, total blood loss, blood loss in drainage, and the decrease in hemoglobin than could the control group, the TXA-alone group, and the drain-clamping group (P < .05). There was no significant difference between the occurrence of deep venous thrombosis between the included groups (P > .05). Conclusions: TXA plus drain-clamping can achieve the maximum effects of hemostasis in patients prepared for primary TKA. Because the number and the quality of the included studies were limited, more high-quality randomized controlled trials are needed to identify the optimal dose of TXA and the clamping hours in patients prepared for TKA. PMID:28658157
Frändberg, Sofia; Waldner, Berit; Konar, Jan; Rydberg, Lennart; Fasth, Anders; Holgersson, Jan
2016-09-01
The National Swedish Cord Blood Bank (NS-CBB) is altruistic and publicly funded. Herein we describe the status of the bank and the impact of delayed versus early clamping on cell number and volume. Cord Blood Units (CBUs) were collected at two University Hospitals in Sweden. Collected volume and nucleated cell content (TNC) were investigated in 146 consecutive Cord Blood (CB) collections sampled during the first quarter of 2012 and in 162 consecutive CB collections done in the first quarter of 2013, before and after clamping practices were changed from immediate to late (60 s) clamping. NS-CBB now holds close to 5000 units whereof 30 % are from non-Caucasian or mixed origins. Delayed clamping had no major effect on collection efficiency. The volume collected was slightly reduced (mean difference, 8.1 ml; 95 % CI, 1.3-15.0 ml; p = 0.02), while cell recovery was not (p = 0.1). The proportion of CBUs that met initial total TNC banking criteria was 60 % using a TNC threshold of 12.5 × 10(8), and 47 % using a threshold of 15 × 10(8) for the early clamping group and 52 and 37 % in the late clamping group. Following implementation of delayed clamping practices at NS-CBB; close to 40 % of the collections in the late clamping group still met the high TNC banking threshold and were eligible for banking, implicating that that cord blood banking is feasible with delayed clamping practices.
Sui, Hongshu; Yi, Yaling; Yao, Jianrong; Liang, Bo; Sun, Xingshen; Hu, Shanming; Uc, Aliye; Nelson, Deborah J.; Ode, Katie Larson; Philipson, Louis H.; Engelhardt, John F.; Norris, Andrew W.
2014-01-01
Ferrets are an important emerging model of cystic fibrosis related diabetes. However, there is little documented experience in the use of advanced techniques to quantify aspects of diabetes pathophysiology in the ferret. Glycemic clamps are the gold standard technique to assess both insulin sensitivity and insulin secretion in humans and animal models of diabetes. We therefore sought to develop techniques for glycemic clamps in ferrets. To assess insulin sensitivity, we performed euglycemic hyperinsulinemic clamps in 5–6 week old ferrets in the anesthetized and conscious states. To assess insulin secretion, we performed hyperglycemic clamps in conscious ferrets. To evaluate responsiveness of ferret islet and entero-insular hormones to low glucose, a portion of the hyperglycemic clamps were followed by a hypoglycemic clamp. The euglycemic hyperinsulinemic clamps demonstrated insulin responsiveness in ferrets similar to that previously observed in humans and rats. The anesthetic isoflurane induced marked insulin resistance, whereas lipid emulsion induced mild insulin resistance. In conscious ferrets, glucose appearance was largely suppressed at 4 mU/kg/min insulin infusion, whereas glucose disposal was progressively increased at 4 and 20 mU/kg/min insulin. Hyperglycemic clamp induced first phase insulin secretion. Hypoglycemia induced a rapid diminishment of insulin, as well as a rise in glucagon and pancreatic polypeptide levels. The incretins GLP-1 and GIP were affected minimally by hyperglycemic and hypoglycemic clamp. These techniques will prove useful in better defining the pathophysiology in ferrets with cystic fibrosis related diabetes. PMID:24594704
Yajuan, Xiao; Xin, Liang; Zhiyuan, Li
2012-01-01
The patch clamp technique is commonly used in electrophysiological experiments and offers direct insight into ion channel properties through the characterization of ion channel activity. This technique can be used to elucidate the interaction between a drug and a specific ion channel at different conformational states to understand the ion channel modulators’ mechanisms. The patch clamp technique is regarded as a gold standard for ion channel research; however, it suffers from low throughput and high personnel costs. In the last decade, the development of several automated electrophysiology platforms has greatly increased the screen throughput of whole cell electrophysiological recordings. New advancements in the automated patch clamp systems have aimed to provide high data quality, high content, and high throughput. However, due to the limitations noted above, automated patch clamp systems are not capable of replacing manual patch clamp systems in ion channel research. While automated patch clamp systems are useful for screening large amounts of compounds in cell lines that stably express high levels of ion channels, the manual patch clamp technique is still necessary for studying ion channel properties in some research areas and for specific cell types, including primary cells that have mixed cell types and differentiated cells that derive from induced pluripotent stem cells (iPSCs) or embryonic stem cells (ESCs). Therefore, further improvements in flexibility with regard to cell types and data quality will broaden the applications of the automated patch clamp systems in both academia and industry. PMID:23346269
MATLAB implementation of a dynamic clamp with bandwidth >125 KHz capable of generating INa at 37°C
Clausen, Chris; Valiunas, Virginijus; Brink, Peter R.; Cohen, Ira S.
2012-01-01
We describe the construction of a dynamic clamp with bandwidth >125 KHz that utilizes a high performance, yet low cost, standard home/office PC interfaced with a high-speed (16 bit) data acquisition module. High bandwidth is achieved by exploiting recently available software advances (code-generation technology, optimized real-time kernel). Dynamic-clamp programs are constructed using Simulink, a visual programming language. Blocks for computation of membrane currents are written in the high-level matlab language; no programming in C is required. The instrument can be used in single- or dual-cell configurations, with the capability to modify programs while experiments are in progress. We describe an algorithm for computing the fast transient Na+ current (INa) in real time, and test its accuracy and stability using rate constants appropriate for 37°C. We then construct a program capable of supplying three currents to a cell preparation: INa, the hyperpolarizing-activated inward pacemaker current (If), and an inward-rectifier K+ current (IK1). The program corrects for the IR drop due to electrode current flow, and also records all voltages and currents. We tested this program on dual patch-clamped HEK293 cells where the dynamic clamp controls a current-clamp amplifier and a voltage-clamp amplifier controls membrane potential, and current-clamped HEK293 cells where the dynamic clamp produces spontaneous pacing behavior exhibiting Na+ spikes in otherwise passive cells. PMID:23224681
Sui, Hongshu; Yi, Yaling; Yao, Jianrong; Liang, Bo; Sun, Xingshen; Hu, Shanming; Uc, Aliye; Nelson, Deborah J; Ode, Katie Larson; Philipson, Louis H; Engelhardt, John F; Norris, Andrew W
2014-01-01
Ferrets are an important emerging model of cystic fibrosis related diabetes. However, there is little documented experience in the use of advanced techniques to quantify aspects of diabetes pathophysiology in the ferret. Glycemic clamps are the gold standard technique to assess both insulin sensitivity and insulin secretion in humans and animal models of diabetes. We therefore sought to develop techniques for glycemic clamps in ferrets. To assess insulin sensitivity, we performed euglycemic hyperinsulinemic clamps in 5-6 week old ferrets in the anesthetized and conscious states. To assess insulin secretion, we performed hyperglycemic clamps in conscious ferrets. To evaluate responsiveness of ferret islet and entero-insular hormones to low glucose, a portion of the hyperglycemic clamps were followed by a hypoglycemic clamp. The euglycemic hyperinsulinemic clamps demonstrated insulin responsiveness in ferrets similar to that previously observed in humans and rats. The anesthetic isoflurane induced marked insulin resistance, whereas lipid emulsion induced mild insulin resistance. In conscious ferrets, glucose appearance was largely suppressed at 4 mU/kg/min insulin infusion, whereas glucose disposal was progressively increased at 4 and 20 mU/kg/min insulin. Hyperglycemic clamp induced first phase insulin secretion. Hypoglycemia induced a rapid diminishment of insulin, as well as a rise in glucagon and pancreatic polypeptide levels. The incretins GLP-1 and GIP were affected minimally by hyperglycemic and hypoglycemic clamp. These techniques will prove useful in better defining the pathophysiology in ferrets with cystic fibrosis related diabetes.
NASA Astrophysics Data System (ADS)
Banerjee, J.; Verma, M. K.; Manna, S.; Ghosh, S.
2006-02-01
Noise profile of Voltage Dependent Anion Channel (VDAC) is investigated in open channel state. Single-channel currents through VDAC from mitochondria of rat brain reconstituted into a planar lipid bilayer are recorded under different voltage clamped conditions across the membrane. Power spectrum analysis of current indicates power law noise of 1/f nature. Moreover, this 1/f nature of the open channel noise is seen throughout the range of applied membrane potential from -30 to +30 mV. It is being proposed that 1/f noise in open ion channel arises out of obstruction in the passage of ions across the membrane. The process is recognised as a phenomenon of self-organized criticality (SOC) like sandpile avalanche and other physical systems. Based on SOC it has been theoretically established that the system of ion channel follows power law noise as observed in our experiments. We also show that the first-time return probability of current fluctuations obeys a power law distribution.
Dynamic assembly of Hda and the sliding clamp in the regulation of replication licensing.
Kim, Jin S; Nanfara, Michael T; Chodavarapu, Sundari; Jin, Kyeong S; Babu, Vignesh M P; Ghazy, Mohamed A; Chung, Scisung; Kaguni, Jon M; Sutton, Mark D; Cho, Yunje
2017-04-20
Regulatory inactivation of DnaA (RIDA) is one of the major regulatory mechanisms of prokaryotic replication licensing. In RIDA, the Hda-sliding clamp complex loaded onto DNA directly interacts with adenosine triphosphate (ATP)-bound DnaA and stimulates the hydrolysis of ATP to inactivate DnaA. A prediction is that the activity of Hda is tightly controlled to ensure that replication initiation occurs only once per cell cycle. Here, we determined the crystal structure of the Hda-β clamp complex. This complex contains two pairs of Hda dimers sandwiched between two β clamp rings to form an octamer that is stabilized by three discrete interfaces. Two separate surfaces of Hda make contact with the β clamp, which is essential for Hda function in RIDA. The third interface between Hda monomers occludes the active site arginine finger, blocking its access to DnaA. Taken together, our structural and mutational analyses of the Hda-β clamp complex indicate that the interaction of the β clamp with Hda controls the ability of Hda to interact with DnaA. In the octameric Hda-β clamp complex, the inability of Hda to interact with DnaA is a novel mechanism that may regulate Hda function. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.
Dynamic assembly of Hda and the sliding clamp in the regulation of replication licensing
Kim, Jin S.; Nanfara, Michael T.; Chodavarapu, Sundari; Jin, Kyeong S.; Babu, Vignesh M. P.; Ghazy, Mohamed A.; Chung, Scisung
2017-01-01
Abstract Regulatory inactivation of DnaA (RIDA) is one of the major regulatory mechanisms of prokaryotic replication licensing. In RIDA, the Hda–sliding clamp complex loaded onto DNA directly interacts with adenosine triphosphate (ATP)-bound DnaA and stimulates the hydrolysis of ATP to inactivate DnaA. A prediction is that the activity of Hda is tightly controlled to ensure that replication initiation occurs only once per cell cycle. Here, we determined the crystal structure of the Hda–β clamp complex. This complex contains two pairs of Hda dimers sandwiched between two β clamp rings to form an octamer that is stabilized by three discrete interfaces. Two separate surfaces of Hda make contact with the β clamp, which is essential for Hda function in RIDA. The third interface between Hda monomers occludes the active site arginine finger, blocking its access to DnaA. Taken together, our structural and mutational analyses of the Hda–β clamp complex indicate that the interaction of the β clamp with Hda controls the ability of Hda to interact with DnaA. In the octameric Hda–β clamp complex, the inability of Hda to interact with DnaA is a novel mechanism that may regulate Hda function. PMID:28168278
Minimizing blood loss at cesarean-hysterectomy for placenta previa percreta.
Belfort, Michael A; Shamshiraz, Alireza A; Fox, Karin
2017-01-01
Preventing blood loss at the time of a cesarean delivery during a scheduled, nonemergent cesarean hysterectomy for placenta percreta may reduce the need for crystalloid and blood product transfusion. Commonly a classical hysterotomy is created and this can result in as much as a 500-800 mL blood loss before the hysterotomy is closed. Our technique involves placement of 4 full-thickness interrupted sutures in a box pattern to create an unperfused area of upper uterine segment. Diathermy is used to open the uterus to the membranes in the center of the "box" without blood loss. A finger is then inserted between the membranes and uterus to create a space into which 1 side of an 80-mm linear cutting stapler is introduced. The other side of the stapler is then attached and clamped closed, and the stapler is activated. Forward motion of the lever lays down 2 rows of staples, and backward movement of the lever divides the uterine muscle between the 2 staple lines. The stapler is removed and reloaded and reintroduced 1 or 2 times as needed to create an avascular hysterotomy large enough to atraumatically deliver the baby. The membranes are then opened and the baby is delivered. Following this the umbilical cord is clamped and cut without any attempt to remove the placenta, replaced in the uterine cavity, and the hysterotomy is closed with a running locked suture that incorporates the membrane edges. The hysterectomy then proceeds. In most cases there is minimal blood loss (usually <20 mL) from the cesarean delivery. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Hashemi, Ali Saadatmand; Sattarvand, Javad
2015-03-01
Using simulation modeling, different management systems of the open pit mining equipment including non-dispatching, dispatching and blending solutions have been studied for the Sungun copper mine. Developed model has the capability of considering detailed features of both loading and hauling equipment. Productivity assessment scenarios have been established on the constructed model and the outputs revealed the noteworthy impact of the match factor of the trucks to the loaders on the production rate by over 40%. A dispatching simulation model with the objective function of minimizing truck waiting times have been developed and 7.8% improvement obtained by applying a flexible assignment of the trucks for the loaders compared to the fixed assignment system. Finally ore grade blending control unit has been introduced into the model. Getting the advantages of the newly added module it became possible to monitor the portion of material excavated from different operating benches and control truck dispatching rules for keeping the overall ore grade exactly at desired value.
Spectral infrared hemispherical reflectance measurements for LDEF tray clamps
NASA Technical Reports Server (NTRS)
Cromwell, B. K.; Shepherd, S. D.; Pender, C. W.; Wood, B. E.
1993-01-01
Infrared hemispherical reflectance measurements that were made on 58 chromic acid anodized tray clamps from LDEF are described. The measurements were made using a hemiellipsoidal mirror reflectometer with interferometer for wavelengths between 2-15 microns. The tray clamps investigated were from locations about the entire spacecraft and provided the opportunity for comparing the effects of atomic oxygen at each location. Results indicate there was essentially no dependence on atomic oxygen fluence for the surfaces studied, but there did appear to be a slight dependence on solar radiation exposure. The reflectances of the front sides of the tray clamps consistently were slightly higher than for the protected rear tray clamp surfaces.
Advanced motor driven clamped borehole seismic receiver
Engler, B.P.; Sleefe, G.E.; Striker, R.P.
1993-02-23
A borehole seismic tool is described including a borehole clamp which only moves perpendicular to the borehole. The clamp is driven by an electric motor, via a right angle drive. When used as a seismic receiver, the tool has a three part housing, two of which are hermetically sealed. Accelerometers or geophones are mounted in one hermetically sealed part, the electric motor in the other hermetically sealed part, and the clamp and right angle drive in the third part. Preferably the tool includes cable connectors at both ends. Optionally a shear plate can be added to the clamp to extend the range of the tool.
Llinás, R; Sugimori, M; Lin, J W; Cherksey, B
1989-01-01
A Ca2+-channel blocker derived from funnel-web spider toxin (FTX) has made it possible to define and study the ionic channels responsible for the Ca2+ conductance in mammalian Purkinje cell neurons and the preterminal in squid giant synapse. In cerebellar slices, FTX blocked Ca2+-dependent spikes in Purkinje cells, reduced the spike afterpotential hyperpolarization, and increased the Na+-dependent plateau potential. In the squid giant synapse, FTX blocked synaptic transmission without affecting the presynaptic action potential. Presynaptic voltage-clamp results show blockage of the inward Ca2+ current and of transmitter release. FTX was used to isolate channels from cerebellum and squid optic lobe. The isolated product was incorporated into black lipid membranes and was analyzed by using patch-clamp techniques. The channel from cerebellum exhibited a 10- to 12-pS conductance in 80 mM Ba2+ and 5-8 pS in 100 mM Ca2+ with voltage-dependent open probabilities and kinetics. High Ba2+ concentrations at the cytoplasmic side of the channel increased the average open time from 1 to 3 msec to more than 1 sec. A similar channel was also isolated from squid optic lobe. However, its conductance was higher in Ba2+, and the maximum opening probability was about half of that derived from cerebellar tissue and also was sensitive to high cytoplasmic Ba2+. Both channels were blocked by FTX, Cd2+, and Co2+ but were not blocked by omega-conotoxin or dihydropyridines. These results suggest that one of the main Ca2+ conductances in mammalian neurons and in the squid preterminal represents the activation of a previously undefined class of Ca2+ channel. We propose that it be termed the "P" channel, as it was first described in Purkinje cells. Images PMID:2537980
Llinás, R; Sugimori, M; Lin, J W; Cherksey, B
1989-03-01
A Ca2+-channel blocker derived from funnel-web spider toxin (FTX) has made it possible to define and study the ionic channels responsible for the Ca2+ conductance in mammalian Purkinje cell neurons and the preterminal in squid giant synapse. In cerebellar slices, FTX blocked Ca2+-dependent spikes in Purkinje cells, reduced the spike afterpotential hyperpolarization, and increased the Na+-dependent plateau potential. In the squid giant synapse, FTX blocked synaptic transmission without affecting the presynaptic action potential. Presynaptic voltage-clamp results show blockage of the inward Ca2+ current and of transmitter release. FTX was used to isolate channels from cerebellum and squid optic lobe. The isolated product was incorporated into black lipid membranes and was analyzed by using patch-clamp techniques. The channel from cerebellum exhibited a 10- to 12-pS conductance in 80 mM Ba2+ and 5-8 pS in 100 mM Ca2+ with voltage-dependent open probabilities and kinetics. High Ba2+ concentrations at the cytoplasmic side of the channel increased the average open time from 1 to 3 msec to more than 1 sec. A similar channel was also isolated from squid optic lobe. However, its conductance was higher in Ba2+, and the maximum opening probability was about half of that derived from cerebellar tissue and also was sensitive to high cytoplasmic Ba2+. Both channels were blocked by FTX, Cd2+, and Co2+ but were not blocked by omega-conotoxin or dihydropyridines. These results suggest that one of the main Ca2+ conductances in mammalian neurons and in the squid preterminal represents the activation of a previously undefined class of Ca2+ channel. We propose that it be termed the "P" channel, as it was first described in Purkinje cells.
Anterior dental microwear textures show habitat-driven variability in Neandertal behavior.
Krueger, Kristin L; Ungar, Peter S; Guatelli-Steinberg, Debbie; Hublin, Jean-Jacques; Pérez-Pérez, Alejandro; Trinkaus, Erik; Willman, John C
2017-04-01
The causes of Neandertal anterior tooth wear patterns, including labial rounding, labial scratches, and differential anterior-posterior wear, have been debated for decades. The most common explanation is the "stuff-and-cut" hypothesis, which describes Neandertals clamping down on a piece of meat and slicing a portion close to their lips. "Stuff-and-cut" has been accepted as a general aspect of Neandertal behavior without fully assessing its variability. This study analyzes anterior dental microwear textures across habitats, locations, and time intervals to discern possible variation in Neandertal anterior tooth-use behavior. Forty-five Neandertals from 24 sites were analyzed, represented by high-resolution replicas of permanent anterior teeth. The labial surface was scanned for antemortem microwear using a white-light confocal profiler. The resultant 3D-point clouds, representing 204 × 276 μm for each specimen, were uploaded into SSFA software packages for texture characterization. Statistical analyses, including MANOVAs, ANOVAs, and pairwise comparisons, were completed on ranked microwear data. Neandertal descriptive statistics were also compared to 10 bioarchaeological samples of known or inferred dietary and behavioral regimes. The Neandertal sample varied significantly by habitat, suggesting this factor was a principal driving force for differences in Neandertal anterior tooth-use behaviors. The Neandertals from open habitats showed significantly lower anisotropy and higher textural fill volume than those inhabiting more closed, forested environments. The texture signature from the open-habitat Neandertals was most similar to that of the Ipiutak and Nunavut, who used their anterior teeth for intense clamping and grasping behaviors related to hide preparation. Those in more closed habitats were most similar to the Arikara, who did not participate in non-dietary behaviors. These Neandertal individuals had a broad range of texture values consistent with non-dietary and dietary behaviors, suggesting they varied more in anterior tooth-use behaviors and exploited a wider variety of plant and animal resources than did those from open habitats. Copyright © 2017 Elsevier Ltd. All rights reserved.
Isotani, Shuji; Shimoyama, Hirofumi; Yokota, Isao; China, Toshiyuki; Hisasue, Shin-ichi; Ide, Hisamitsu; Muto, Satoru; Yamaguchi, Raizo; Ukimura, Osamu; Horie, Shigeo
2015-05-01
To evaluate the feasibility and accuracy of virtual partial nephrectomy analysis, including a color-coded three-dimensional virtual surgical planning and a quantitative functional analysis, in predicting the surgical outcomes of robot-assisted partial nephrectomy. Between 2012 and 2014, 20 patients underwent virtual partial nephrectomy analysis before undergoing robot-assisted partial nephrectomy. Virtual partial nephrectomy analysis was carried out with the following steps: (i) evaluation of the arterial branch for selective clamping by showing the vascular-supplied area; (ii) simulation of the optimal surgical margin in precise segmented three-dimensional model for prediction of collecting system opening; and (iii) detailed volumetric analyses and estimates of postoperative renal function based on volumetric change. At operation, the surgeon identified the targeted artery and determined the surgical margin according to the virtual partial nephrectomy analysis. The surgical outcomes between the virtual partial nephrectomy analysis and the actual robot-assisted partial nephrectomy were compared. All 20 patients had negative cancer surgical margins and no urological complications. The tumor-specific renal arterial supply areas were shown in color-coded three-dimensional model visualization in all cases. The prediction value of collecting system opening was 85.7% for sensitivity and 100% for specificity. The predicted renal resection volume was significantly correlated with actual resected specimen volume (r(2) = 0.745, P < 0.001). The predicted estimated glomerular filtration rate was significantly correlated with actual postoperative estimated glomerular filtration rate (r(2) = 0.736, P < 0.001). Virtual partial nephrectomy analysis is able to provide the identification of tumor-specific renal arterial supply, prediction of collecting system opening and prediction of postoperative renal function. This technique might allow urologists to compare various arterial clamping methods and resection margins with surgical outcomes in a non-invasive manner. © 2015 The Japanese Urological Association.
Lishko, Polina; Clapham, David E.; Navarro, Betsy; Kirichok, Yuriy
2014-01-01
Sperm intracellular pH and calcium concentration ([Ca2+]i) are two central factors that control sperm activity within the female reproductive tract. As such, the ion channels of the sperm plasma membrane that alter intracellular sperm [Ca2+] and pH play important roles in sperm physiology and the process of fertilization. Indeed, sperm ion channels regulate sperm motility, control sperm chemotaxis toward the egg in some species, and may trigger the acrosome reaction. Until recently, our understanding of these important molecules was rudimentary due to the inability to patch-clamp spermatozoa and directly record the activity of these ion channels under voltage clamp. Recently, we overcame this technical barrier and developed a method for reproducible application of the patch-clamp technique to mouse and human spermatozoa. This chapter covers important aspects of application of the patch-clamp technique to spermatozoa, such as selection of the electrophysiological equipment, isolation of spermatozoa for patch-clamp experiments, formation of the gigaohm seal with spermatozoa, and transition into the whole-cell mode of recording. We also discuss potential pitfalls in application of the patch-clamp technique to flagellar ion channels. PMID:23522465
USSR Report, International Affairs
1987-02-11
shown that the cycle "A New Development—Assimilation in Production " has accelerated to practically twice its original speed thanks to these forms of... new production capacities to manufacture hydrodynamic transmissions for scrapers and loaders, and in doing so, will be assisted by a partner—the...creation of new forms of production through joint efforts. Of primary importance in achieving these new forms are mobile and flexible contacts that are in
Conceptual Design of a Robotic Loader System for Remote Missile Launchers.
1985-09-01
artifcial intelligence were sur- veyed in order to assess their space applicability and to identify areas which can be developed/adapted to European...such data bases as NTIS and COMPENDEX. The second computer aided search was done through the U. S. Army information services at Redstone Arsenal...Lockheed Corporation. The first DIALOG data base explored was NTIS (National Technical Information Services, U.S. Dept. of Commerce), which contains
2002-01-01
TS, Manley SA, Olopade OI, Cummings S, Garber JE, Bernhardt B, Antman K, Russo D, Wood ME, Mullineau L, Isaacs C, Peshkin B, Buys S, Venne V, Rowley... Antman K, Russo D, Wood ME, Mullineau L, Isaacs C, Peshkin B, Buys S, Venne V, Rowley PT, Loader S, Offit K, Robson M, Hampel H, Brener D, Winer EP
2006-09-01
tank with adjacent training structure and hoist for inflatable boat training. An indoor climbing wall, a weight/fitness room, and staff and student...climbing; rappelling/litter evacuation; Tyrolean traverses; suspended harness parachuting emergency procedures; aircraft hoist infiltration...characteristics in common. Bulldozers, backhoes, and front-end loaders would be on site throughout periods of excavation and/or site preparation. Dump
Expedient Repair of Structural Facilities (ERSF). Volume 1. ERSF System Development
1992-01-01
slabs, will require a different vehicle for transportation; for example a flatbed truck. Specialized equipment, such as the shotcrete machine described in...1) glued, laminated timber (glulam) column insertion and (2) mechanical shoring jack insertion. Both systems were ranked essentially equally after...gage wire mesh; - (optional) 100 rebar ties; and - in some cases, a bulldozer, front-end loader, and flatbed truck. c. Training Since a new piece of
Interpretive computer simulator for the NASA Standard Spacecraft Computer-2 (NSSC-2)
NASA Technical Reports Server (NTRS)
Smith, R. S.; Noland, M. S.
1979-01-01
An Interpretive Computer Simulator (ICS) for the NASA Standard Spacecraft Computer-II (NSSC-II) was developed as a code verification and testing tool for the Annular Suspension and Pointing System (ASPS) project. The simulator is written in the higher level language PASCAL and implented on the CDC CYBER series computer system. It is supported by a metal assembler, a linkage loader for the NSSC-II, and a utility library to meet the application requirements. The architectural design of the NSSC-II is that of an IBM System/360 (S/360) and supports all but four instructions of the S/360 standard instruction set. The structural design of the ICS is described with emphasis on the design differences between it and the NSSC-II hardware. The program flow is diagrammed, with the function of each procedure being defined; the instruction implementation is discussed in broad terms; and the instruction timings used in the ICS are listed. An example of the steps required to process an assembly level language program on the ICS is included. The example illustrates the control cards necessary to assemble, load, and execute assembly language code; the sample program to to be executed; the executable load module produced by the loader; and the resulting output produced by the ICS.
Raffler, Nastaran; Hermanns, Ingo; Sayn, Detlef; Göres, Benno; Ellegast, Rolf; Rissler, Jörg
2010-01-01
The drivers of ten vehicles (tram, helicopter, saloon car, van, forklift, two mobile excavators, wheel loader, tractor, elevating platform truck) were studied with regard to the combined exposures of whole-body vibration and awkward posture during occupational tasks. Seven degrees of freedom (DOFs), or body angles, were recorded as a function of time by means of the CUELA measuring system (Computer-assisted registration and long-term analysis of musculoskeletal workloads) for the purpose of posture assessment. The vibrational exposure is expressed as the vector sum of the frequency-weighted accelerations in the three Cartesian coordinates; these were recorded simultaneously with the posture measurement. Based upon the percentage of working time spent under different workloads, a scheme is proposed for classification of the two exposures into three categories. In addition, a risk of adverse health effects classified as low, possible or high can be assigned to the combination of the two exposures. With regard to posture, the most severe exposure was measured for the drivers of the wheel loader and for the tractor driver, whereas the lowest exposure was measured for the helicopter pilots and van drivers. With regard to the combination of whole-body and posture exposures, the tractor driver and the elevating platform truck driver exhibited the highest workloads.
Cell-Detection Technique for Automated Patch Clamping
NASA Technical Reports Server (NTRS)
McDowell, Mark; Gray, Elizabeth
2008-01-01
A unique and customizable machinevision and image-data-processing technique has been developed for use in automated identification of cells that are optimal for patch clamping. [Patch clamping (in which patch electrodes are pressed against cell membranes) is an electrophysiological technique widely applied for the study of ion channels, and of membrane proteins that regulate the flow of ions across the membranes. Patch clamping is used in many biological research fields such as neurobiology, pharmacology, and molecular biology.] While there exist several hardware techniques for automated patch clamping of cells, very few of those techniques incorporate machine vision for locating cells that are ideal subjects for patch clamping. In contrast, the present technique is embodied in a machine-vision algorithm that, in practical application, enables the user to identify good and bad cells for patch clamping in an image captured by a charge-coupled-device (CCD) camera attached to a microscope, within a processing time of one second. Hence, the present technique can save time, thereby increasing efficiency and reducing cost. The present technique involves the utilization of cell-feature metrics to accurately make decisions on the degree to which individual cells are "good" or "bad" candidates for patch clamping. These metrics include position coordinates (x,y) in the image plane, major-axis length, minor-axis length, area, elongation, roundness, smoothness, angle of orientation, and degree of inclusion in the field of view. The present technique does not require any special hardware beyond commercially available, off-the-shelf patch-clamping hardware: A standard patchclamping microscope system with an attached CCD camera, a personal computer with an imagedata- processing board, and some experience in utilizing imagedata- processing software are all that are needed. A cell image is first captured by the microscope CCD camera and image-data-processing board, then the image data are analyzed by software that implements the present machine-vision technique. This analysis results in the identification of cells that are "good" candidates for patch clamping (see figure). Once a "good" cell is identified, a patch clamp can be effected by an automated patchclamping apparatus or by a human operator. This technique has been shown to enable reliable identification of "good" and "bad" candidate cells for patch clamping. The ultimate goal in further development of this technique is to combine artificial-intelligence processing with instrumentation and controls in order to produce a complete "turnkey" automated patch-clamping system capable of accurately and reliably patch clamping cells with a minimum intervention by a human operator. Moreover, this technique can be adapted to virtually any cellular-analysis procedure that includes repetitive operation of microscope hardware by a human.
Modulation of inward rectifier potassium channel by toosendanin, a presynaptic blocker.
Wang, Z F; Shi, Y L
2001-07-01
The effect of toosendanin, a presynaptic blocker, on the inward rectifier potassium channel (K(Kir)) of hippocampal CA1 pyramidal neurons of rats was studied by the single-channel patch-clamp technique. The results showed that toosendanin had an inhibitory effect on K(Kir) in an excised inside-out patch of the neuron under a symmetrical 150 mM K(+) condition. By decreasing the slower open time constant and increasing the slower close time constant, toosendanin (1x10(-6)-1x10(-4) g/ml) significantly reduced the open probability of the channel in a concentration-dependent manner. Meanwhile, a dose-dependent reduction in unitary conductance of the channel was also detected after toosendanin application. These data offer an explanation for toosendanin-induced facilitation of neurotransmitter release and antibotulismic effect of the drug.
Lotus birth, a holistic approach on physiological cord clamping.
Zinsser, Laura A
2018-04-01
The positive effects of delayed cord clamping (DCC) has been extensively researched. DCC means: waiting at least one minute after birth before clamping and cutting the cord or till the pulsation has stopped. With physiological clamping and cutting (PCC) the clamping and cutting can happen at the earliest after the pulsation has stopped. With a Lotus birth, no clamping and cutting of the cord is done. A woman called Clair Lotus Day imitated the holistic approach of PCC from an anthropoid ape in 1974. The chimpanzee did not separate the placenta from the newborn. The aim of this case report is to discuss and learn a different approach in the third stage of labour. Three cases of Lotus birth by human beings were observed. All three women gave birth in an out-of-hospital setting and had ambulant postnatal care. The placenta was washed, salted and herbs were put on 2-3h post partum. The placenta was wrapped in something that absorbs the moisture. The salting was repeated with a degreasing frequency depending on moistness of the placenta. On life day six all three Lotus babies experiences a natural separation of the cord. All three Lotus birth cases were unproblematic, no special incidence occurred. One should differentiate between early cord clamping (ECC), delayed cord clamping (DCC) and physiological cord clamping (PCC). Lotus birth might lead to an optimisation of the bonding and attachment. Research is needed in the areas of both PCC and Lotus birth. Copyright © 2017 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.
Su'etsugu, Masayuki; Takata, Makoto; Kubota, Toshio; Matsuda, Yusaku; Katayama, Tsutomu
2004-06-01
In Escherichia coli, the ATP-DnaA protein initiates chromosomal replication. After the DNA polymerase III holoenzyme is loaded on to DNA, DnaA-bound ATP is hydrolysed in a manner depending on Hda protein and the DNA-loaded form of the DNA polymerase III sliding clamp subunit, which yields ADP-DnaA, an inactivated form for initiation. This regulatory DnaA-inactivation represses extra initiation events. In this study, in vitro replication intermediates and structured DNA mimicking replicational intermediates were first used to identify structural prerequisites in the process of DnaA-ATP hydrolysis. Unlike duplex DNA loaded with sliding clamps, primer RNA-DNA heteroduplexes loaded with clamps were not associated with DnaA-ATP hydrolysis, and duplex DNA provided in trans did not rescue this defect. At least 40-bp duplex DNA is competent for the DnaA-ATP hydrolysis when a single clamp was loaded. The DnaA-ATP hydrolysis was inhibited when ATP-DnaA was tightly bound to a DnaA box-bearing oligonucleotide. These results imply that the DnaA-ATP hydrolysis involves the direct interaction of ATP-DnaA with duplex DNA flanking the sliding clamp. Furthermore, Hda protein formed a stable complex with the sliding clamp. Based on these, we suggest a mechanical basis in the DnaA-inactivation that ATP-DnaA interacts with the Hda-clamp complex with the aid of DNA binding. Copyright Blackwell Publishing Limited
Mechanical coupling for a rotor shaft assembly of dissimilar materials
Shi, Jun [Glastonbury, CT; Bombara, David [New Hartford, CT; Green, Kevin E [Broad Brook, CT; Bird, Connic [Rocky Hill, CT; Holowczak, John [South Windsor, CT
2009-05-05
A mechanical coupling for coupling a ceramic disc member to a metallic shaft includes a first wedge clamp and a second wedge clamp. A fastener engages a threaded end of a tie-bolt to sandwich the ceramic disc between the wedge clamps. An axial spring is positioned between the fastener and the second wedge clamp to apply an axial preload along the longitudinal axis. Another coupling utilizes a rotor shaft end of a metallic rotor shaft as one wedge clamp. Still another coupling includes a solid ceramic rotor disc with a multiple of tie-bolts radially displaced from the longitudinal axis to exert the preload on the solid ceramic rotor disc.
Launch Lock Assemblies with Reduced Preload and Spacecraft Isolation Systems Including the Same
NASA Technical Reports Server (NTRS)
Barber, Tim Daniel (Inventor); Young, Ken (Inventor); Hindle, Timothy (Inventor)
2016-01-01
Launch lock assemblies with reduced preload are provided. The launch lock assembly comprises first and second mount pieces, a releasable clamp device, and a pair of retracting assemblies. Each retracting assembly comprises a pair of toothed members having interacting toothed surfaces. The releasable clamp device normally maintains the first and second mount pieces in clamped engagement. When the releasable clamp device is actuated, the first and second mount pieces are released from clamped engagement and one toothed member of each retracting assembly moves in an opposite direction relative to the other one toothed member of the other retracting assembly to define an axial gap on each side of the first mount piece.
Vaughn, Mark R.; Hafenrichter, Everett S.; Chapa, Agapito C.; Harris, Steven M.; Martinez, Marcus J.; Baty, Roy S.
2006-02-28
A system for clamping two tubular members together in an end-to-end relationship uses a split ring with a V-shaped outer rim that can engage a clamping surface on each member. The split ring has a relaxed closed state where the ends of the ring are adjacent and the outside diameter of the split ring is less than the minimum inside diameter of the members at their ends. The members are clamped when the split ring is spread into an elastically stretched position where the ring rim is pressed tightly against the interior surfaces of the members. Mechanisms are provided for removing the spreader so the split ring will return to the relaxed state, releasing the clamped members.
Pollono, Louis P.
1979-01-01
A pipe support for high temperature, thin-walled piping runs such as those used in nuclear systems. A section of the pipe to be supported is encircled by a tubular inner member comprised of two walls with an annular space therebetween. Compacted load-bearing thermal insulation is encapsulated within the annular space, and the inner member is clamped to the pipe by a constant clamping force split-ring clamp. The clamp may be connected to pipe hangers which provide desired support for the pipe.
Self-aligning fixture used in lathe chuck jaw refacing
NASA Technical Reports Server (NTRS)
Linn, C. C.
1965-01-01
Self-aligning tool positions and rigidly holds lathe chuck jaws for refacing and truing of the clamping surface. The jaws clamp the fixture in the manner of clamping a workpiece. The fixture can be modified to accommodate four-jawed checks.
Park, Joo Hyun; Choi, Sung Wook; Shin, Eun Ho; Park, Myung Hoon; Kim, Myung Ku
2017-01-01
Although intraarticular tranexamic acid (IA-TXA) administration or drainage clamping are popular methods used to reduce blood loss after total knee replacement (TKR), the protocol remains controversial. We aimed (1) to establish new protocols through investigating whether two methods, that is, low-dose (500 mg) IA-TXA plus 30-min drain clamping and drainage clamping for the first 3 h without IA-TXA, can reduce blood loss and blood transfusion after unilateral TKR and (2) to make recommendations related to clinical application. This study, conducted from September 2014 to June 2016 related to enrolled 95 patients with primary osteoarthritis who were to have a unilateral cemented TKR, was nonrandomized and retrospective. In group A, the drain was released following tourniquet deflation. In group B, 500-mg TXA was injected into the knee joint via a drain tube after fascia closure and the drain was clamped for the first 30 min to prevent leakage. In group C, the drain was clamped for the first 3-h postoperation. Demographic characteristics and clinical data were collected, including the levels of hematocrit (Hct), the total blood loss (TBL), drained blood volume (BV), the amount of blood transfused, and any complications that developed. We found a significantly lower postoperative TBL, drained BV, decreasing Hct level, and less transfused BV in the IA-TXA injection group (group B) and the 3-h drainage clamping group (group C) compared to the conventional negative drainage group (group A; p < 0.001). There was no significant difference between groups B and C ( p = 0.99). The drainage clamping method can be safer than IA-TXA administration in patients with risk factor of venous thromboembolic complication. Furthermore, the IA-TXA administration can be more optimal than drainage clamping in patients with high bleeding tendency or lateral retinacular release during TKR, who would be concerned about postoperative wound complication.
Atomistic Simulations of Complex DNA DSBs and the Interactions with Ku70/80 Heterodimer
NASA Technical Reports Server (NTRS)
Hu, Shaowen; Cucinotta, Francis A.
2011-01-01
Compared to DNA with simple DSBs, the complex lesions can enhance the hydrogen bonds opening rate at the DNA terminus, and increase the mobility of the whole duplex. Binding of Ku drastically reduces the structural disruption and flexibility caused by the complex lesions. In all complex DSBs systems, the binding of DSB terminus with Ku70 is softened while the binding of the middle duplex with Ku80 is tightened. Binding of Ku promotes the rigidity of DNA duplexes, due to the clamp structure of the inner surface of the rings of Ku70/80.
Measurement of Single Channel Currents from Cardiac Gap Junctions
NASA Astrophysics Data System (ADS)
Veenstra, Richard D.; Dehaan, Robert L.
1986-08-01
Cardiac gap junctions consist of arrays of integral membrane proteins joined across the intercellular cleft at points of cell-to-cell contact. These junctional proteins are thought to form pores through which ions can diffuse from cytosol to cytosol. By monitoring whole-cell currents in pairs of embryonic heart cells with two independent patch-clamp circuits, the properties of single gap junction channels have been investigated. These channels had a conductance of about 165 picosiemens and underwent spontaneous openings and closings that were independent of voltage. Channel activity and macroscopic junctional conductance were both decreased by the uncoupling agent 1-octanol.
Yadav, Yad Ram; Parihar, Vijay; Agarwal, Moneet; Bhatele, Pushp Raj
2012-01-01
The management of intraoperative bleeding during removal of a large hyper vascular meningioma is crucial for safe and efficient surgery. Preoperative embolization of meningioma is the best way to reduce vascularity of meningiomas but this technique is not readily available, costly and has its own limitations. The study is aimed to evaluate the use of temporary clamping of external carotid artery to reduce blood loss and operating time during excision of large convexity, parasagittal or temporal base meningiomas. A prospective study of 115 consecutively operated meningiomas of size 5 cms or more were operated from January 2002 to December2010. Temporary clamping of external carotid artery was done in 61 while 51 cases were managed without clamping. There was significant reduction of blood loss, operative time and blood transfusion given in the temporary clipping group compared to non clipping group. There was stitch abscess in two patients each in clamping, and non clamping group. There was no scalp necrosis or mortality in any of the group. Temporary clamping of external carotid artery is a safe, simple and cost-effective alternative to embolization for the surgery of large meningiomas. This can be practiced at all the centers.
Qin, Qingquan; Xu, Feng; Cao, Yongqing; Ro, Paul I; Zhu, Yong
2012-08-20
The effect of clamping on resonance frequency and thus measured Young's modulus of nanowires (NWs) is systematically investigated via a combined experimental and simulation approach. ZnO NWs are used in this work as an example. The resonance tests are performed in situ inside a scanning electron microscope and the NWs are cantilevered on a tungsten probe by electron-beam-induced deposition (EBID) of hydrocarbon. EBID is repeated several times to deposit more hydrocarbons at the same location. The resonance frequency increases with the increasing clamp size until approaching that under the "fixed" boundary condition. The critical clamp size is identified as a function of NW diameter and NW Young's modulus. This work: 1) exemplifies the importance of considering the effect of clamping in measurements of Young's modulus using the resonance method, and 2) demonstrates that the true Young's modulus can be measured if the critical clamp size is reached. Design guidelines on the critical clamp size are provided. Such design guidelines can be extended to other one-dimensional nanostructures such as carbon nanotubes. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Force-controlled patch clamp of beating cardiac cells.
Ossola, Dario; Amarouch, Mohamed-Yassine; Behr, Pascal; Vörös, János; Abriel, Hugues; Zambelli, Tomaso
2015-03-11
From its invention in the 1970s, the patch clamp technique is the gold standard in electrophysiology research and drug screening because it is the only tool enabling accurate investigation of voltage-gated ion channels, which are responsible for action potentials. Because of its key role in drug screening, innovation efforts are being made to reduce its complexity toward more automated systems. While some of these new approaches are being adopted in pharmaceutical companies, conventional patch-clamp remains unmatched in fundamental research due to its versatility. Here, we merged the patch clamp and atomic force microscope (AFM) techniques, thus equipping the patch-clamp with the sensitive AFM force control. This was possible using the FluidFM, a force-controlled nanopipette based on microchanneled AFM cantilevers. First, the compatibility of the system with patch-clamp electronics and its ability to record the activity of voltage-gated ion channels in whole-cell configuration was demonstrated with sodium (NaV1.5) channels. Second, we showed the feasibility of simultaneous recording of membrane current and force development during contraction of isolated cardiomyocytes. Force feedback allowed for a gentle and stable contact between AFM tip and cell membrane enabling serial patch clamping and injection without apparent cell damage.
Peptide- and proton-driven allosteric clamps catalyze anthrax toxin translocation across membranes
Das, Debasis; Krantz, Bryan A.
2016-01-01
Anthrax toxin is an intracellularly acting toxin in which sufficient information is available regarding the structure of its transmembrane channel, allowing for detailed investigation of models of translocation. Anthrax toxin, comprising three proteins—protective antigen (PA), lethal factor (LF), and edema factor—translocates large proteins across membranes. Here we show that the PA translocase channel has a transport function in which its catalytic active sites operate allosterically. We find that the phenylalanine clamp (ϕ-clamp), the known conductance bottleneck in the PA translocase, gates as either a more closed state or a more dilated state. Thermodynamically, the two channel states have >300-fold different binding affinities for an LF-derived peptide. The change in clamp thermodynamics requires distant α-clamp and ϕ-clamp sites. Clamp allostery and translocation are more optimal for LF peptides with uniform stereochemistry, where the least allosteric and least efficiently translocated peptide had a mixed stereochemistry. Overall, the kinetic results are in less agreement with an extended-chain Brownian ratchet model but, instead, are more consistent with an allosteric helix-compression model that is dependent also on substrate peptide coil-to-helix/helix-to-coil cooperativity. PMID:27506790
Plasma Chamber Restraints in Ignitor and Relevant Disruption Analysis
NASA Astrophysics Data System (ADS)
Gasparotto, M.; Cucchiaro, A.; Capriccioli, A.; Celentano, G.; Rita, C.; Roccella, M.; Macco, B.; Micheli, I.; Ferrari, G.; Orlandi, S.; Coppi, B.
2000-10-01
The plasmas chamber (PC) of Ignitor is made of 12 D-shaped toroidal sectors of Inconel 625 welded together by automatic remote equipment. The thickness of the inboard wall is 17 mm while the middle and outboard walls are 26 mm thick. The PC is supported through the ports by the C-Clamp structure of the toroidal magnet. The main function of the PC supports is to resist the vertical and radial electromagnetic loads and to allow for free movement under thermal loads while providing electrical insulation from the C-Clamps and cryostat. The largest estimated loads are due to a Vertical Displacement Event (VDE) disruption that is followed by a thermal quench and then by the current quench. The vertical supports involve a connection of each radial port to the C-Clamp structure by a link system that withstands the calculated loads. The radial supports resist, with high stiffness, the centripetal and centrifugal forces. The end flange of each radial port is connected to the C-Clamp structure by a clamping sleeve device. The clamping sleeves are hydraulically operated to provide locking during discharge. The clamping sleeves of the radial support system have been validated by an appropriate series of tests.
Diverter bop system and method for a bottom supported offshore drilling rig
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roche, J. R.; Alexander, G. G.; Carbaugh, W. L.
1985-06-25
A system and method for installing a fluid flow controller and telescoping spools beneath an offshore bottom supported drilling rig rotary table is disclosed. Upper and lower telescoping spools are provided for initially connecting a Diverter/BOP convertible fluid flow controller between structural casing in the well and a permanent housing beneath the drilling rig rotary table. Clamp means are provided for clamping the rig vent line to an opening in the housing wall of the fluid flow controller during drilling of the borehole through the structural casing in preparation for setting and cementing the conductor casing. In that mode, themore » system is adapted as a diverter system. After the well is drilled for the conductor casing and the conductor casing is cemented and cut off at its top, a mandrel is fitted at the top of the conductor casing to which the lower end of the lower spool may be connected. The system may be used in this configuration as a diverter system, or after removal of the vent line and connection of a kill line to the housing outlet, the system may be used as a low pressure blowout preventer system.« less
Double-arterial cannulation for aortic valve replacement with porcelain aorta.
De Paulis, Ruggero; Maselli, Daniele; Scaffa, Raffaele; Nardella, Saverio
2009-10-01
We describe a new technique of aortic valve replacement (AVR) in patients with porcelain aorta. Three patients (mean age 75 years) were treated. The cardiopulmonary bypass (CPB) was established after side-graft right axillary artery and direct femoral artery cannulation. Venous drainage was obtained by atrio-caval cannulation. The procedures were performed in mild hypothermia (30 degrees C). Cerebral perfusion was carried out by clamping the innominate artery and all epiaortic vessels. The aorta was endoclamped by a Foley balloon inserted into the isthmus. The aorta was then opened longitudinally for 10 cm to expose and replace the aortic valve. Near-infra-red spectroscopy (NIRS) and bilateral radial artery pressure were used to monitor effective cerebral perfusion. Operative mortality was absent. The mean time of CPB was 73 min. NIRS-derived tissue oxygenation was maintained above 55%. Postoperative course was uneventful. This technique has several advantages: first, the cannulation of right axillary and the common femoral artery allows simultaneous cerebral and systemic perfusion. Second, any form of cross-clamp is avoided and the aorta is occluded away from the epiaortic vessels. Third, there is an increased freedom to choose the best place for aortotomy.
Acute Pelvic Fractures: II. Principles of Management.
Tile
1996-05-01
The past two decades have seen many advances in pelvic-trauma surgery. Provisional fixation of unstable pelvic-ring disruptions and open-book fractures with a pelvic clamp or an external frame with a supracondylar pin has proved markedly beneficial in the resuscitative phase of management. In the completely unstable pelvis, external clamps and frames can act only as provisional fixation and should be combined with skeletal traction. The traction pin is usually used only until a definitive form of stabilization can be applied to keep the pelvic ring in a reduced position. If the patient is too ill to allow operative intervention, the traction pin can remain in place with the external frame as definitive treatment. Symphyseal disruptions and medial ramus fractures should be plated at the time of laparotomy. Lateral ramus fractures can usually be controlled with external frames. A role has been suggested for percutaneous retrograde fixation of the superior pubic ramus; however, the benefits to be gained may not be enough to outweigh the serious risks of penetrating the hip, and this technique should therefore be used only by surgeons trained in its performance. The techniques for posterior fixation are becoming more standardized, but all still carry significant risks, especially to neurologic structures.
Cheong, Hyeonsook; Paudyal, Dilli Parasad; Jun, Jae Yeoul; Yeum, Cheol Ho; Yoon, Pyung Jin; Park, Chan Guk; Kim, Man Yoo; So, Insuk; Kim, Ki Whan; Choi, Seok
2005-10-31
Extracts of pine needles (Pinus densiflora Sieb. et Zucc.) have diverse physiological and pharmacological actions. In this study we show that pine needle extract alters pacemaker currents in interstitial cells of Cajal (ICC) by modulating ATP-sensitive K+ channels and that this effect is mediated by prostaglandins. In whole cell patches at 30 degrees , ICC generated spontaneous pacemaker potentials in the current clamp mode (I = 0), and inward currents (pacemaker currents) in the voltage clamp mode at a holding potential of -70 mV. Pine needle extract hyperpolarized the membrane potential, and in voltage clamp mode decreased both the frequency and amplitude of the pacemaker currents, and increased the resting currents in the outward direction. It also inhibited the pacemaker currents in a dose-dependent manner. Because the effects of pine needle extract on pacemaker currents were the same as those of pinacidil (an ATP-sensitive K+ channel opener) we tested the effect of glibenclamide (an ATP-sensitive K+ channels blocker) on ICC exposed to pine needle extract. The effects of pine needle extract on pacemaker currents were blocked by glibenclamide. To see whether production of prostaglandins (PGs) is involved in the inhibitory effect of pine needle extract on pacemaker currents, we tested the effects of naproxen, a non-selective cyclooxygenase (COX-1 and COX-2) inhibitor, and AH6809, a prostaglandin EP1 and EP2 receptor antagonist. Naproxen and AH6809 blocked the inhibitory effects of pine needle extract on ICC. These results indicate that pine needle extract inhibits the pacemaker currents of ICC by activating ATP-sensitive K+ channels via the production of PGs.
NASA Technical Reports Server (NTRS)
Calco, Frank S. (Inventor)
1991-01-01
A quick release toggle clamp that utilizes a spring that requires a deliberate positive action for disengagement is presented. The clamp has a sliding bolt that provides a latching mechanism. The bolt is moved by a handle that tends to remain in an engaged position while under tension.
Cutburth, Ronald W.; Smauley, David A.
1987-01-01
A clamp or dog is disclosed which preferably comprises a slotted stepped cylindrical body which is inserted into a hole in a workpiece and then fastened to a base or fixture using a screw which is inserted through the slot. The stepped configuration provides an annular clamping surface which securely clamps the workpiece against the base or fixture. The slotted cylindrical configuration permits adjustment of the workpiece and retaining clamp in any direction, i.e., over 360.degree., relative to the mounting position of the screw in the base or fixture.
SiC-Based Miniature High-Temperature Cantilever Anemometer
NASA Technical Reports Server (NTRS)
Okojie, Robert S.; Fralick, Gustave; Saad, George J.
2004-01-01
The figure depicts a miniature cantilever-type anemometer that has been developed as a prototype of compact, relatively nonintrusive anemometers that can function at temperatures up to 600 C and that can be expected to be commercially mass-producible at low cost. The design of this anemometer, and especially the packaging aspect of the design, is intended to enable measurement of turbulence in the high-temperature, high-vibration environment of a turbine engine or in any similar environment. The main structural components of the anemometer include a single-crystal SiC cantilever and two polycrystalline SiC clamping plates, all made from chemical-vapor-deposited silicon carbide. Fabrication of these components from the same basic material eliminates thermal-expansion mismatch, which has introduced spurious thermomechanical stresses in cantilever-type anemometers of prior design. The clamping plates are heavily oxidized to improve electrical insulation at high temperature. A cavity that serves as a receptacle for the clamped end of the cantilever is etched into one end of one clamping plate. Trenches that collectively constitute a socket for a multipin electrical plug (for connection to external electronic circuitry) are etched into the opposite end of this clamping plate. Metal strips for electrical contact are deposited on one face of the other clamping plate. Piezoresistive single-crystal SiC thin-film strain gauges are etched in the n-type SiC epilayer in a Wheatstone-bridge configuration. Metal contact pads on the cantilever that extend into the clamping-receptacle area, are obtained by deposition and patterning using standard semiconductor photolithography and etching methods. The cantilever and the two clamping plates are assembled into a sandwich structure that is then clamped in a stainless-steel housing. The Wheatstone- bridge carrying SiC cantilever with the metal contact pads on the piezoresistors is slid into the receptacle in the bottom clamping plate. The top clamping plate is brought into contact with the bottom plate so that the narrow section of the metal strips on the top clamp plate aligns with the metal contact pads on the cantilever. When the parts are clamped together, the metal strips provide electrical connections between the Wheatstone-bridge contact points and the sides the trenches that constitute the socket for the multipin electrical plug. Hence, to connect the Wheatstone bridge to external circuitry for processing of the anemometer readout, one need only insert the plug in the socket. In operation, the cantilever end of the stainless-steel housing is mounted flush with an engine wall and the unclamped portion of the cantilever is exposed into the flow. The cantilever is deflected in direct proportion to the force induced by component of flow parallel to the engine wall and perpendicular to the broad exposed face of the cantilever. The maximum strain on the cantilever occurs at the clamped edge and is measured by the piezoresistors, which are located there. The corresponding changes in resistance manifest themselves in the output of the Wheatstone bridge.
Mechanics of wafer bonding: Effect of clamping
NASA Astrophysics Data System (ADS)
Turner, K. T.; Thouless, M. D.; Spearing, S. M.
2004-01-01
A mechanics-based model is developed to examine the effects of clamping during wafer bonding processes. The model provides closed-form expressions that relate the initial geometry and elastic properties of the wafers to the final shape of the bonded pair and the strain energy release rate at the interface for two different clamping configurations. The results demonstrate that the curvature of bonded pairs may be controlled through the use of specific clamping arrangements during the bonding process. Furthermore, it is demonstrated that the strain energy release rate depends on the clamping configuration and that using applied loads usually leads to an undesirable increase in the strain energy release rate. The results are discussed in detail and implications for process development and bonding tool design are highlighted.
1980-08-01
DESIGN GROUP I GROUP II GROUP III (XMl Tank) (Chrysler UCOFT) (GE UCOFT) Pretest ...training plan design are that: 1. Tank Commanders and Gunners will have been transition trained on the "MI prior to assign- mint to a test group . Cuirrent...posttests on the XMI for each group . Also, Loaders and Drivers are required for the Group I device pretest , gunnery portion of the
Automated Gun Laying System for Self-Propelled Artillery Weapons.
1980-05-30
model designed specifically to the requirements of a test bed system. The system configuration and characteristics were specified through a series of...proposed by the contractor was further defined, utilizing the M109 component information provided by the COTR. Math models were developed to predict system...data. The model used for the TB-I program did not have the capability for a remote reset function, hence it was necessary to instruct the crew (loader
The CRRES Langmuir Probe and Fluxgate Magnetometer Instrument
1989-05-09
Gbntract tenager Branch Chief i r FOR THE COWhbDER RITA C. SAGALYN Division Director Qualified requestors may obtain additional copies from the... Computations 73 2.9 Sawtooth Generation 80 2.10 Bias Sweeps 84 2.11 Main Program Loader 96 2.12 Boom Deployment 98 2.13 General Utilities...separated by 100 meters. The other pair of conductors are cylindrical wire boom elements also in the spin plane that are separated by an effective
Apple App Store as a Business Model Supporting U.S. Navy Requirements
2011-10-25
credit card identity information for charging the required $99/year fee. Actual payment of the fee is handled by putting the developer program...required for the App Store. Applications are submitted via iTunes Connect (http://itunesconnect.apple.com). Table 1 gives a list of the...still being processed by the iTunes Connect system. Invalid Binary—Appears when a binary is received through the Application Loader and has been
Radiation Dose Assessment for Military Personnel of the Enewetak Atoll Cleanup Project (1977-1980)
2018-04-13
population are detailed. 2.1 Enewetak Atoll Setting Enewetak Atoll (Figure 2) is approximately 23 by 17 statute miles with the long axis running ...Survey and stake the boundaries of soil excision areas; • Remove excess brush; • Excise (scrape surface with bulldozer blade ) the area and...JTGJ-2 and FRST members Survey instruments, soil sampling tools, dump trucks, bucket and backhoe loaders, water tank trucks, scrape blades
2012 ENFORCE. Project Manager Force Projection Briefing to ENFORCE
2012-04-16
M-ATV Logistics MRAP Vehicle Systems (Joint Program) •Navistar MaxxPro •GDLS RG-31 •BAE-TVS Caiman •BAE RG-33 SOCOM •BAE RG-33 SOCOM AUV...Handling Equipment • Container Handling Equipment •Loaders • Cranes •Dozers •Excavators Force Sustainment Systems •Cargo Airdrop Systems...Boruff DPM: Mr. Dennis Mazurek Mine Resistant Ambush Protected Vehicles PM: Mr. Carl Owens DPM: COL Jeffrey Carr Tactical
INTERIOR VIEW, NORTH QUARRY, LOOKING WEST. IN THE FOREGROUND ON ...
INTERIOR VIEW, NORTH QUARRY, LOOKING WEST. IN THE FOREGROUND ON THE FIRST BENCH, POWDER HILLS ARE PRIMED FOR DOLOMITE EXTRACTION. ON THE SECOND BENCH, THE DRILL TEAM IS LAYING OUT THE NEXT SHOTS. ON THE TOP BENCH, A 245 CATERPILLAR LOADER FILLS A 55-TON CATERPILLAR ROCK TRUCK WITH EXTRACTED DOLOMITE FOR TRANSPORT TO THE DOLOMITE CRUSHING AND SCREENING PLANT. - Wade Sand & Gravel Company, North Quarry, State Highway 78, Thomas, Jefferson County, AL
Explicit frequency equations of free vibration of a nonlocal Timoshenko beam with surface effects
NASA Astrophysics Data System (ADS)
Zhao, Hai-Sheng; Zhang, Yao; Lie, Seng-Tjhen
2018-02-01
Considerations of nonlocal elasticity and surface effects in micro- and nanoscale beams are both important for the accurate prediction of natural frequency. In this study, the governing equation of a nonlocal Timoshenko beam with surface effects is established by taking into account three types of boundary conditions: hinged-hinged, clamped-clamped and clamped-hinged ends. For a hinged-hinged beam, an exact and explicit natural frequency equation is obtained. However, for clamped-clamped and clamped-hinged beams, the solutions of corresponding frequency equations must be determined numerically due to their transcendental nature. Hence, the Fredholm integral equation approach coupled with a curve fitting method is employed to derive the approximate fundamental frequency equations, which can predict the frequency values with high accuracy. In short, explicit frequency equations of the Timoshenko beam for three types of boundary conditions are proposed to exhibit directly the dependence of the natural frequency on the nonlocal elasticity, surface elasticity, residual surface stress, shear deformation and rotatory inertia, avoiding the complicated numerical computation.
Non-invasive method and apparatus for measuring pressure within a pliable vessel
NASA Technical Reports Server (NTRS)
Shimizu, M. (Inventor)
1983-01-01
A non-invasive method and apparatus is disclosed for measuring pressure within a pliable vessel such as a blood vessel. The blood vessel is clamped by means of a clamping structure having a first portion housing a pressure sensor and a second portion extending over the remote side of the blood vessel for pressing the blood vessel into engagement with the pressure sensing device. The pressure sensing device includes a flat deflectable diaphragm portion arranged to engage a portion of the blood vessel flattened against the diaphragm by means of the clamp structure. In one embodiment, the clamp structure includes first and second semicylindrical members held together by retaining rings. In a second embodiment the clamp structure is of one piece construction having a solid semicylindrical portion and a hollow semicylindrical portion with a longitudinal slot in the follow semicylindrical portion through which a slip the blood vessel. In a third embodiment, an elastic strap is employed for clamping the blood vessel against the pressure sensing device.
Term babies with delayed cord clamping: an approach in preventing anemia (.).
Ertekin, Arif Aktug; Nihan Ozdemir, Nilufer; Sahinoglu, Zeki; Gursoy, Tugba; Erbil, Nazan; Kaya, Erdal
2016-09-01
We investigated the effects of delayed and early clamping of the cord on the hematologic status of the baby at birth and at the end of second month. Umbilical cord of 74 babies were clamped in the first 30 s (Group 1) and 76 were clamped at 90-120 s (Group 2). Levels of hemoglobin, hematocrit, iron and ferritin were analyzed from the umbilical cord blood at birth and from the venous samples at the end of second month. Hemoglobin, hematocrit, iron and ferritin levels of cord blood were similar in both groups. However, their levels other than ferritin were higher in Group 2 at the end of second month. Two babies had respiratory distress and twelve neonates received phototherapy in Group 2 whereas only five neonates received phototherapy in Group 1. Term babies to whom delayed cord clamping was performed had improved hematological parameters at the end of second month. Therefore, delaying cord clamping in these babies may be a favorible approach in preventing anemia.
Vibration mode analysis of the proton exchange membrane fuel cell stack
NASA Astrophysics Data System (ADS)
Liu, B.; Liu, L. F.; Wei, M. Y.; Wu, C. W.
2016-11-01
Proton exchange membrane fuel cell (PEMFC) stacks usually undergo vibration during packing, transportation, and serving time, in particular for those used in the automobiles or portable equipment. To study the stack vibration response, based on finite element method (FEM), a mode analysis is carried out in the present paper. Using this method, we can distinguish the local vibration from the stack global modes, predict the vibration responses, such as deformed shape and direction, and discuss the effects of the clamping configuration and the clamping force magnitude on vibration modes. It is found that when the total clamping force remains the same, increasing the bolt number can strengthen the stack resistance to vibration in the clamping direction, but cannot obviously strengthen stack resistance to vibration in the translations perpendicular to clamping direction and the three axis rotations. Increasing the total clamping force can increase both of the stack global mode and the bolt local mode frequencies, but will decrease the gasket local mode frequency.
Tensil Film Clamps And Mounting Block For Viscoelastometers
NASA Technical Reports Server (NTRS)
Stoakley, Diane M.; St. Clair, Anne K.; Little, Bruce D.
1989-01-01
Set of clamps and mounting block developed for use in determining tensile moduli and damping properties of films in manually operated or automated commercial viscoelastometer. These clamps and block provide uniformity of sample gripping and alignment in instrument. Dependence on operator and variability of data greatly reduced.
Combined effects of VX-770 and VX-809 on several functional abnormalities of F508del-CFTR channels.
Kopeikin, Z; Yuksek, Z; Yang, H-Y; Bompadre, S G
2014-09-01
The most common cystic fibrosis-associated mutation, the deletion of phenylalanine 508 (F508del), results in channels with poor membrane expression and impaired function. VX-770, a clinically approved drug for treatment of CF patients carrying the G551D mutation, and VX-809, a corrector shown in vitro to increase membrane expression of mutant channels, are currently undergoing clinical trials, but functional data at the molecular level is still lacking. The effect of VX-770 and VX-809 on the multiple functional defects of F508del-CFTR was assessed via excised inside-out patch-clamp experiments. VX-770 completely restores the low opening-rate of F508del-CFTR, with smaller open-time increase, in temperature-corrected and VX-809-treated channels. The shorter locked-open time of hydrolysis-deficient F508del-CFTR is also prolonged by VX-770. VX-809 does not improve channel function by itself as previously reported. The results from these studies can be interpreted as an equilibrium shift toward the open-channel conformation of F508del-CFTR channels. Copyright © 2014 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.
Intraoperative IR imaging in the cardiac operating room
NASA Astrophysics Data System (ADS)
Szabo, Tamas; Fazekas, Levente; Horkay, Ferenc; Geller, Laslu; Gyongy, Tibor; Juhasz-Nagy, Alexander
1999-07-01
The high blood flow rate and the considerable metabolic activity render the myocardium a possible candidate for IR imaging. The study was aimed to test cardiothermography in evaluating arterial bypass graft patency and in assessing myocardial protection during open-heart surgery. Ten patients underwent arterial bypass grafting. Thermograms were obtained immediately before and after opening the grafts. As the bypasses were opened in hypothermia the warmer blood coming from the extracorporeal circulation readily delineated graft and coronary anatomy. By the end of the 5 min observation period, the revascularized area exhibited a temperature increase of 5.9 +/- 0.7 degrees C. The affectivity of antegrade cardioplegia was monitored in 38 patients undergoing either valve implantations or aorto- coronary bypass surgery. Thermographic imags were taken after sternotomy, before aortic cross-clamping and after administrating the 4 degrees C cardioplegic solution. Most of the patients displayed adequate myocardial cooling, moreover the bypass-group exhibited a more profound temperature-decrease. In conclusion, cardiothermography can visualize arterial grafts, recipient coronaries and collaterals seconds after opening by bypass, thus it properly evaluated arterial bypass graft patency. The obtained images could easily be analyzed for qualitative flow- and quantitative temperature changes. Myocardial protection could also be safely assessed with thermography.
Fuel cell assembly unit for promoting fluid service and electrical conductivity
Jones, Daniel O.
1999-01-01
Fluid service and/or electrical conductivity for a fuel cell assembly is promoted. Open-faced flow channel(s) are formed in a flow field plate face, and extend in the flow field plate face between entry and exit fluid manifolds. A resilient gas diffusion layer is located between the flow field plate face and a membrane electrode assembly, fluidly serviced with the open-faced flow channel(s). The resilient gas diffusion layer is restrained against entering the open-faced flow channel(s) under a compressive force applied to the fuel cell assembly. In particular, a first side of a support member abuts the flow field plate face, and a second side of the support member abuts the resilient gas diffusion layer. The support member is formed with a plurality of openings extending between the first and second sides of the support member. In addition, a clamping pressure is maintained for an interface between the resilient gas diffusion layer and a portion of the membrane electrode assembly. Preferably, the support member is spikeless and/or substantially flat. Further, the support member is formed with an electrical path for conducting current between the resilient gas diffusion layer and position(s) on the flow field plate face.
30 CFR 77.603 - Clamping of trailing cables to equipment.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clamping of trailing cables to equipment. 77.603 Section 77.603 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... UNDERGROUND COAL MINES Trailing Cables § 77.603 Clamping of trailing cables to equipment. Trailing cables...
Code of Federal Regulations, 2014 CFR
2014-10-01
... (2) Nonmetallic flexible hose is acceptable but must— (i) Not be used in lengths of more than 30... reinforced with wire braid. (iv) Be fitted with suitable, corrosion resistant, compression fittings; and (v) Be installed with two clamps at each end of the hose, if designed for use with clamps. Clamps must...
Code of Federal Regulations, 2010 CFR
2010-10-01
... (2) Nonmetallic flexible hose is acceptable but must— (i) Not be used in lengths of more than 30... reinforced with wire braid. (iv) Be fitted with suitable, corrosion resistant, compression fittings; and (v) Be installed with two clamps at each end of the hose, if designed for use with clamps. Clamps must...
Code of Federal Regulations, 2012 CFR
2012-10-01
... (2) Nonmetallic flexible hose is acceptable but must— (i) Not be used in lengths of more than 30... reinforced with wire braid. (iv) Be fitted with suitable, corrosion resistant, compression fittings; and (v) Be installed with two clamps at each end of the hose, if designed for use with clamps. Clamps must...
Code of Federal Regulations, 2013 CFR
2013-10-01
... (2) Nonmetallic flexible hose is acceptable but must— (i) Not be used in lengths of more than 30... reinforced with wire braid. (iv) Be fitted with suitable, corrosion resistant, compression fittings; and (v) Be installed with two clamps at each end of the hose, if designed for use with clamps. Clamps must...
An ideal clamping analysis for a cross-ply laminate
NASA Technical Reports Server (NTRS)
Valisetty, R. R.; Murthy, P. L. N.; Rehfield, L. W.
1988-01-01
Different elementary clamping models are discussed for a three layer crossply laminate to study the sensitivity of clamping to the definition of cross-sectional rotation. All of these models leave a considerable residual warping at the edges. Using a complimentary energy principle and principle of superposition, an analysis is conducted to reduce this residual warping. This led to the identification of exact interior solution corresponding to the ideal clamping. This study also suggests a presence of stress singularities at the corners and between different layers near the fixed edge.
Clamp force and alignment checking device
Spicer, John Patrick; Cai, Wayne W.; Chakraborty, Debejyo; Mink, Keith
2017-04-11
A check fixture measures a total clamp force applied by a welder device. The welder device includes a welding horn having a plurality of weld pads and welding anvil having a plurality of weld pads. The check fixture includes a base member operatively supporting a plurality of force sensors. The base member and the force sensors are received between the weld pads of the welding horn and the anvil pads of the welding anvil. Each force sensor is configured to measure an individual clamp force applied thereto by corresponding weld and anvil pads when the base member is received between the welding horn and the welding anvil and the welder device is in the clamped position. The individual clamp forces are used to determine whether the weld and/or anvil pads are worn or misaligned.
Acoustic plane waves incident on an oblique clamped panel in a rectangular duct
NASA Technical Reports Server (NTRS)
Unz, H.; Roskam, J.
1980-01-01
The theory of acoustic plane waves incident on an oblique clamped panel in a rectangular duct was developed from basic theoretical concepts. The coupling theory between the elastic vibrations of the panel (plate) and the oblique incident acoustic plane wave in infinite space was considered in detail, and was used for the oblique clamped panel in the rectangular duct. The partial differential equation which governs the vibrations of the clamped panel (plate) was modified by adding to it stiffness (spring) forces and damping forces. The Transmission Loss coefficient and the Noise Reduction coefficient for oblique incidence were defined and derived in detail. The resonance frequencies excited by the free vibrations of the oblique finite clamped panel (plate) were derived and calculated in detail for the present case.
NASA Astrophysics Data System (ADS)
Frohn, Peter; Engel, Bernd; Groth, Sebastian
2018-05-01
Kinematic forming processes shape geometries by the process parameters to achieve a more universal process utilizations regarding geometric configurations. The kinematic forming process Incremental Swivel Bending (ISB) bends sheet metal strips or profiles in plane. The sequence for bending an arc increment is composed of the steps clamping, bending, force release and feed. The bending moment is frictionally engaged by two clamping units in a laterally adjustable bending pivot. A minimum clamping force hindering the material from slipping through the clamping units is a crucial criterion to achieve a well-defined incremental arc. Therefore, an analytic description of a singular bent increment is developed in this paper. The bending moment is calculated by the uniaxial stress distribution over the profiles' width depending on the bending pivot's position. By a Coulomb' based friction model, necessary clamping force is described in dependence of friction, offset, dimensions of the clamping tools and strip thickness as well as material parameters. Boundaries for the uniaxial stress calculation are given in dependence of friction, tools' dimensions and strip thickness. The results indicate that changing the bending pivot to an eccentric position significantly affects the process' bending moment and, hence, clamping force, which is given in dependence of yield stress and hardening exponent. FE simulations validate the model with satisfactory accordance.
Liang, Cunman; Wang, Fujun; Tian, Yanling; Zhao, Xingyu; Zhang, Hongjie; Cui, Liangyu; Zhang, Dawei; Ferreira, Placid
2015-04-01
A novel monolithic piezoelectric actuated wire clamp is presented in this paper to achieve fast, accurate, and robust microelectronic device packaging. The wire clamp has compact, flexure-based mechanical structure and light weight. To obtain large and robust jaw displacements and ensure parallel jaw grasping, a two-stage amplification composed of a homothetic bridge type mechanism and a parallelogram leverage mechanism was designed. Pseudo-rigid-body model and Lagrange approaches were employed to conduct the kinematic, static, and dynamic modeling of the wire clamp and optimization design was carried out. The displacement amplification ratio, maximum allowable stress, and natural frequency were calculated. Finite element analysis (FEA) was conducted to evaluate the characteristics of the wire clamp and wire electro discharge machining technique was utilized to fabricate the monolithic structure. Experimental tests were carried out to investigate the performance and the experimental results match well with the theoretical calculation and FEA. The amplification ratio of the clamp is 20.96 and the working mode frequency is 895 Hz. Step response test shows that the wire clamp has fast response and high accuracy and the motion resolution is 0.2 μm. High speed precision grasping operations of gold and copper wires were realized using the wire clamper.
Double-stator electromagnetic pump having alignment ring and spine assembly
Fanning, Alan Wayne; Olich, Eugene Ellsworth; Dahl, Leslie Roy; Patel, Mahadeo Ratilal
1997-01-01
A support structure for clamping the inner coils and inner lamination rings of an inner stator column of an electromagnetic induction pump to prevent damaging vibration. A spine assembly, including a base plate, a center post and a plurality of ribs, serves as the structural frame for the inner stator. Stacked alignment rings provide structure to the lamination rings and locate them concentrically around the spine assembly central axis. The alignment rings are made of a material having a high thermal expansion coefficient to compensate for the lower expansion of the lamination rings and, overall, provide an approximate match to the expansion of the inner flow duct. The net result is that the radial clamping provided by the duct around the stator iron is maintained (approximately) over a range of temperatures and operating conditions. Axial clamping of the inner stator structure is achieved via tie rods which run through grooves in the ribs and engage the base plate at the bottom of the inner stator and engage a clamping plate at the top. Slender tie rods and a flexible clamping plate are used to provide compliance in the axial clamping system to accommodate differential thermal growth (axially) between the tie rods and lamination ring elements without losing clamping force.
Double-stator electromagnetic pump having alignment ring and spine assembly
Fanning, A.W.; Olich, E.E.; Dahl, L.R.; Patel, M.R.
1997-06-24
A support structure for clamping the inner coils and inner lamination rings of an inner stator column of an electromagnetic induction pump to prevent damaging vibration is disclosed. A spine assembly, including a base plate, a center post and a plurality of ribs, serves as the structural frame for the inner stator. Stacked alignment rings provide structure to the lamination rings and locate them concentrically around the spine assembly central axis. The alignment rings are made of a material having a high thermal expansion coefficient to compensate for the lower expansion of the lamination rings and, overall, provide an approximate match to the expansion of the inner flow duct. The net result is that the radial clamping provided by the duct around the stator iron is maintained (approximately) over a range of temperatures and operating conditions. Axial clamping of the inner stator structure is achieved via tie rods which run through grooves in the ribs and engage the base plate at the bottom of the inner stator and engage a clamping plate at the top. Slender tie rods and a flexible clamping plate are used to provide compliance in the axial clamping system to accommodate differential thermal growth (axially) between the tie rods and lamination ring elements without losing clamping force. 12 figs.
[Analysis of brain hemometabolism behavior during carotid endarterectomy with temporary clamping.].
Duval Neto, Gastão Fernandes; Niencheski, Augusto H
2004-04-01
Carotid endarterectomy with temporary clamping changes cerebral blood flow and cerebral metabolic oxygen demand ratio with consequent oligemic hypoxia or hemometabolic uncoupling. This study aimed at identifying changes in brain hemometabolism, evaluated through changes in oxyhemoglobin saturation in internal jugular vein bulb (SvjO2) during carotid endarterectomy with clamping, and at correlating these changes with potentially interfering factors, mainly end tidal CO2 pressure (P ET CO2) and cerebral perfusion pressure (CPP). Sixteen patients with unilateral carotid stenotic disease scheduled to carotid endarterectomy with carotid arterial clamping were enrolled in this study. Parameters including internal jugular bulb oxyhemoglobin saturation, stump pressure and end tidal CO2 pressure were measured at the following moments: M1 - pre-clamping; M2 - 3 minutes after clamping; M3 - pre-unclamping; M4 - post-unclamping). The comparison among SvjO2 (%, mean +/- SD) in all studied periods has shown differences between those recorded in moments M1 (52.25 +/- 7.87) and M2 (47.43 +/- 9.19). This initial decrease stabilized during temporary clamping, showing decrease in the comparison between M2 and M3 (46.56 +/- 9.25), without statistical significance (p = ns). At post-unclamping, M4 (47.68 +/- 9.12), SvjO2 was increased as compared to M2 and M3 clamping stages, however it was still lower than that of pre-clamping stage M1.(M4 x M1 - p < 0.04) This SvjO2 decrease was followed by significant cerebral perfusion pressure (stump pressure) decrease. Factors influencing this brain hemometabolic uncoupling trend were correlated to P ET CO2. The comparison between CPP and SvjO2 showed weak correlation devoid of statistical significance. In the conditions of our study, SvjO2 measurement is a fast and effective way of clinically monitoring changes in CBF/CMRO2 ratio. Temporary carotid clamping implies in a trend towards brain hemometabolic uncoupling and, as a consequence, to oligemic ischemia; cerebral perfusion pressure does not assesses brain hemometabolic status (CBF and CMRO2 ratio); hypocapnia, may lead to brain hemometabolic uncoupling; P ET CO2 monitoring is an innocuous and efficient way to indirectly monitor PaCO2 preventing inadvertent hypocapnia and its deleterious effects on CBF/CMRO2 ratio during temporary carotid clamping.
Diadenosine tetraphosphate-gating of recombinant pancreatic ATP-sensitive K(+) channels.
Jovanovic, S; Jovanovic, A
2001-02-01
Diadenosine tetraphosphate (Ap4A) has been recently discovered in the pancreatic beta cells where targets ATP-sensitive K(+) (K(ATP)) channels, depolarizes the cell membrane and induces insulin secretion. However, whether Ap4A inhibit pancreatic K(ATP) channels by targeting protein channel complex itself was unknown. Therefore, we coexpressed pancreatic K(ATP) channel subunits, Kir6.2 and SUR1, in COS-7 cells and examined the effect of Ap4A on the single channel behavior using the inside-out configuration of the patch-clamp technique. Ap4A inhibited channel opening in a concentration-dependent manner. Analysis of single channels demonstrated that Ap4A did not change intraburst kinetic behavior of K(ATP) channels, but rather decreased burst duration and increased between-burst duration. It is concluded that Ap4A antagonizes K(ATP) channel opening by targeting channel subunits themselves and by keeping channels longer in closed interburst states.
Gas turbine vane platform element
Campbell, Christian X [Oviedo, FL; Schiavo, Anthony L [Oviedo, FL; Morrison, Jay A [Oviedo, FL
2012-08-28
A gas turbine CMC shroud plate (48A) with a vane-receiving opening (79) that matches a cross-section profile of a turbine vane airfoil (22). The shroud plate (48A) has first and second curved circumferential sides (73A, 74A) that generally follow the curves of respective first and second curved sides (81, 82) of the vane-receiving opening. Walls (75A, 76A, 77A, 78A, 80, 88) extend perpendicularly from the shroud plate forming a cross-bracing structure for the shroud plate. A vane (22) may be attached to the shroud plate by pins (83) or by hoop-tension rings (106) that clamp tabs (103) of the shroud plate against bosses (105) of the vane. A circular array (20) of shroud plates (48A) may be assembled to form a vane shroud ring in which adjacent shroud plates are separated by compressible ceramic seals (93).
Lin, L; Zheng, Y; Qu, J; Bao, G
2000-06-01
Observe the effect of tumor necrosis factor-alpha (TNF-alpha) on calcium-activated potassium channel in ECV304 and the possible involvement of G-protein mediation in the action of TNF-alpha. Using the cell-attached configuration of patch clamp technique. (1) the activity of high-conductance calcium-activated potassium channel (BKca) was recorded. Its conductance is (202.54 +/- 16.62) pS; (2) the activity of BKca was potentiated by 200 U/ml TNF-alpha; (3) G-protein would intensify this TNF-alpha activation. TNF-alpha acted on vascular endothelial cell ECV304 could rapidly activate the activity of BKca. Opening of BKca resulted in membrane hyper-polarization which could increase electro-chemical gradient for the resting Ca2+ influx and open leakage calcium channel, thus resting cytoplasmic free Ca2+ concentration could be elevated. G-protein may exert an important regulation in this process.
Metal-to-ceramic attachment device
Pavelka, Edwin A.; Grindstaff, Quirinus G.; Scheppele, Stuart E.
1985-01-01
A metal-to-ceramic fastening device is disclosed for securing a metal member to a ceramic member with respective confronting surfaces thereon clamped together, comprising a threaded bolt adapted to extend through a bolt hole in the metal member and into an aligned opening in the ceramic member, a rod nut threadedly receiving the bolt and adapted to span the opening in the ceramic member, and a pressure limiting member received on the bolt between the nut and the confronting surface of the metal member for limiting the movement of the nut toward the metal member when the bolt is tightened, so as to limit the pressure applied by the nut to the ceramic member to avoid damage thereto. The fastening device also prevents damage to the ceramic member due to thermal stresses. The pressure limiting member may have a shallow dish-shaped depression facing the rod nut to assist in accommodating thermal stresses.
Timing and efficacy of Ca2+ channel activation in hippocampal mossy fiber boutons.
Bischofberger, Josef; Geiger, Jörg R P; Jonas, Peter
2002-12-15
The presynaptic Ca2+ signal is a key determinant of transmitter release at chemical synapses. In cortical synaptic terminals, however, little is known about the kinetic properties of the presynaptic Ca2+ channels. To investigate the timing and magnitude of the presynaptic Ca2+ inflow, we performed whole-cell patch-clamp recordings from mossy fiber boutons (MFBs) in rat hippocampus. MFBs showed large high-voltage-activated Ca(2+) currents, with a maximal amplitude of approximately 100 pA at a membrane potential of 0 mV. Both activation and deactivation were fast, with time constants in the submillisecond range at a temperature of approximately 23 degrees C. An MFB action potential (AP) applied as a voltage-clamp command evoked a transient Ca2+ current with an average amplitude of approximately 170 pA and a half-duration of 580 microsec. A prepulse to +40 mV had only minimal effects on the AP-evoked Ca2+ current, indicating that presynaptic APs open the voltage-gated Ca2+ channels very effectively. On the basis of the experimental data, we developed a kinetic model with four closed states and one open state, linked by voltage-dependent rate constants. Simulations of the Ca2+ current could reproduce the experimental data, including the large amplitude and rapid time course of the current evoked by MFB APs. Furthermore, the simulations indicate that the shape of the presynaptic AP and the gating kinetics of the Ca2+ channels are tuned to produce a maximal Ca2+ influx during a minimal period of time. The precise timing and high efficacy of Ca2+ channel activation at this cortical glutamatergic synapse may be important for synchronous transmitter release and temporal information processing.
Zheng, Yong; Gu, Qiang; Chen, Hong-Wu; Peng, Huai-Ming; Jia, Dong-Yu; Zhou, Yu; Xiang, Mei-Xiang
The relative preventative efficacy of amiodarone and lidocaine for ventricular fibrillation (VF) after release of an aortic cross-clamp (ACC) during open heart surgery has not been determined. This meta-analysis was designed to systematically evaluate the influence of amiodarone, lidocaine, or placebo on the incidence of VF after ACC. Prospective randomized controlled trials (RCTs) that compared the VF-preventative effects of amiodarone with lidocaine, or amiodarone or lidocaine with placebo were included. PubMed, EMBASE, and the Cochrane Library were searched for relevant RCTs. Fixed or randomized effect models were applied according to the heterogeneity of the data from the selected studies. We included eight RCTs in the analysis. Pooled results suggested that the preventative effects of amiodarone and lidocaine were comparable (relative risk (RR)=1.12, 95% confidence interval (CI): 0.70 to 1.80, P=0.63), but both were superior to the placebo (amiodarone, RR=0.71, 95% CI: 0.51 to 1.00, P=0.05; lidocaine, RR=0.63, 95% CI: 0.46 to 0.88, P=0.006). The percentage of patients requiring electric defibrillation counter shocks (DCSs) did not differ significantly among patients administered amiodarone (RR=0.21, 95% CI: 0.04 to 1.19, P=0.08), lidocaine (RR=2.44, 95% CI: 0.13 to 44.02, P=0.55), or the placebo (RR=0.56, 95% CI: 0.25 to 1.25, P=0.16). Amiodarone and lidocaine are comparably effective in preventing VF after ACC, but the percentage of patients who subsequently require DCSs does not differ among those administered amiodarone, lidocaine, or placebo.
The effect of tensile stress on the conformational free energy landscape of disulfide bonds.
Anjukandi, Padmesh; Dopieralski, Przemyslaw; Ribas-Arino, Jordi; Marx, Dominik
2014-01-01
Disulfide bridges are no longer considered to merely stabilize protein structure, but are increasingly recognized to play a functional role in many regulatory biomolecular processes. Recent studies have uncovered that the redox activity of native disulfides depends on their C-C-S-S dihedrals, χ2 and χ'2. Moreover, the interplay of chemical reactivity and mechanical stress of disulfide switches has been recently elucidated using force-clamp spectroscopy and computer simulation. The χ2 and χ'2 angles have been found to change from conformations that are open to nucleophilic attack to sterically hindered, so-called closed states upon exerting tensile stress. In view of the growing evidence of the importance of C-C-S-S dihedrals in tuning the reactivity of disulfides, here we present a systematic study of the conformational diversity of disulfides as a function of tensile stress. With the help of force-clamp metadynamics simulations, we show that tensile stress brings about a large stabilization of the closed conformers, thereby giving rise to drastic changes in the conformational free energy landscape of disulfides. Statistical analysis shows that native TDi, DO and interchain Ig protein disulfides prefer open conformations, whereas the intrachain disulfide bridges in Ig proteins favor closed conformations. Correlating mechanical stress with the distance between the two a-carbons of the disulfide moiety reveals that the strain of intrachain Ig protein disulfides corresponds to a mechanical activation of about 100 pN. Such mechanical activation leads to a severalfold increase of the rate of the elementary redox S(N)2 reaction step. All these findings constitute a step forward towards achieving a full understanding of functional disulfides.
2012-01-01
Background In the scientific biodiversity community, it is increasingly perceived the need to build a bridge between molecular and traditional biodiversity studies. We believe that the information technology could have a preeminent role in integrating the information generated by these studies with the large amount of molecular data we can find in bioinformatics public databases. This work is primarily aimed at building a bioinformatic infrastructure for the integration of public and private biodiversity data through the development of GIDL, an Intelligent Data Loader coupled with the Molecular Biodiversity Database. The system presented here organizes in an ontological way and locally stores the sequence and annotation data contained in the GenBank primary database. Methods The GIDL architecture consists of a relational database and of an intelligent data loader software. The relational database schema is designed to manage biodiversity information (Molecular Biodiversity Database) and it is organized in four areas: MolecularData, Experiment, Collection and Taxonomy. The MolecularData area is inspired to an established standard in Generic Model Organism Databases, the Chado relational schema. The peculiarity of Chado, and also its strength, is the adoption of an ontological schema which makes use of the Sequence Ontology. The Intelligent Data Loader (IDL) component of GIDL is an Extract, Transform and Load software able to parse data, to discover hidden information in the GenBank entries and to populate the Molecular Biodiversity Database. The IDL is composed by three main modules: the Parser, able to parse GenBank flat files; the Reasoner, which automatically builds CLIPS facts mapping the biological knowledge expressed by the Sequence Ontology; the DBFiller, which translates the CLIPS facts into ordered SQL statements used to populate the database. In GIDL Semantic Web technologies have been adopted due to their advantages in data representation, integration and processing. Results and conclusions Entries coming from Virus (814,122), Plant (1,365,360) and Invertebrate (959,065) divisions of GenBank rel.180 have been loaded in the Molecular Biodiversity Database by GIDL. Our system, combining the Sequence Ontology and the Chado schema, allows a more powerful query expressiveness compared with the most commonly used sequence retrieval systems like Entrez or SRS. PMID:22536971
Laitinen, Juha; Koponen, Hanna; Sippula, Olli; Korpijärvi, Kirsi; Jumpponen, Mika; Laitinen, Sirpa; Aatamila, Marjaleena; Tissari, Jarkko; Karhunen, Tommi; Ojanen, Kari; Jokiniemi, Jorma; Korpinen, Leena
2017-10-01
Fly and bottom ashes are collected at power plants to reduce the environmental effects of energy production. However, handling the ashes causes health problems for operators, maintenance workers and truck drivers at the power plants. Hence, we evaluated ash loaders' peak inhalation exposures to the chemical components of ash and diesel exhausts in open and closed ash loading stations at biomass-fuelled combined heat and power plants. We also carried out chemical and morphological analyses of the ashes to evaluate their health hazard potential in order to find practical technical measures to reduce workers' exposure. On the basis of X-ray diffraction analyses, the main respirable crystalline ash compounds were SiO 2 , CaSO 4 , CaO, Ca 2 Al 2 SiO 7 , NaCl and Ca 3 Al 2 O 6 in the fly ashes and SiO 2 , KAlSi 3 O 8 , NaAlSi 3 O 8 and Ca 2 Al 2 SiO 7 in the bottom ashes. The short-term exposure levels of respirable crystalline silica, inhalable inorganic dust, Cr, Mn, Ni and nitric oxide exceeded their Finnish eight hours occupational exposure limit values in the closed ash loading station. According to our observations, more attention should be paid to the ash-moistening process, the use of tank trucks instead of open cassette flatbed trucks, and the sealing of the loading line from the silo to the truck which would prevent spreading the ash into the air. The idling time of diesel trucks should also be limited, and ash loading stations should be equipped with exhaust gas ventilators. If working conditions make it impossible to keep to the OEL values, workers must use respirators and protect their eyes and skin. Copyright © 2017 Elsevier Ltd. All rights reserved.
Spectral infrared hemispherical reflectance measurements for LDEF tray clamps
NASA Technical Reports Server (NTRS)
Wood, Bobby E.; Cromwell, Brian K.; Pender, Charles W.; Shepherd, Seth D.
1992-01-01
This paper describes infrared hemispherical reflectance measurements (2-15 microns) that were made on 58 chromic acid anodized tray clamps retrieved from the LDEF spacecraft. These clamps were used for maintaining the experiments in place and were located at various locations about the spacecraft. Changes in reflectance of the tray clamps at these locations were compared with atomic oxygen fluxes at the same locations. A decrease in absorption band depth was seen for the surfaces exposed to space indicating that there was some surface layer erosion. In all of the surfaces measured, little evidence of contamination was observed and none of the samples showed evidence of the brown nicotine stain that was so prominent in other experiments. Total emissivity values were calculated for both exposed and unexposed tray clamp surfaces. Only small differences, usually less than 1 percent, were observed. The spectral reflectances were measured using a hemi-ellipsoidal mirror reflectometer matched with an interferometer spectrometer. The rapid scanning capability of the interferometer allowed the reflectance measurements to be made in a timely fashion. The ellipsoidal mirror has its two foci separated by 2 inches and located on the major axis. A blackbody source was located at one focus while the tray clamp samples were located at the conjugate focus. The blackbody radiation was modulated and then focused by the ellipsoid onto the tray clamps. Radiation reflected from the tray clamp was sampled by the interferometer by viewing through a hole in the ellipsoid. A gold mirror (reflectance approximately 98 percent) was used as the reference surface.
Cerebral hemodynamic changes and electroencephalography during carotid endarterectomy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Algotsson, L.; Messeter, K.; Rehncrona, S.
Some patients undergoing endarterectomy for occlusive carotid artery disease run a risk of brain ischemia during cross-clamping of the artery. The present study of 15 patients was undertaken to evaluate changes in cerebral blood flow (CBF), as measured with an intravenous (IV) tracer (133Xenon) technique, and to relate CBF changes to changes in the electroencephalogram (EEG). CBF was measured before and after induction of anesthesia, during cross-clamping of the carotid artery, after release of the clamps, and at 24 hours after the operation. All the patients were anesthetized with methohexitone, fentanyl, and nitrous oxide and oxygen. EEG was continuously recordedmore » during the operation. Carotid artery shunts were not used. In 8 patients, cross-clamping of the carotid artery did not influence the EEG. In this group of patients, induction of anesthesia caused a 38% decrease in CBF, which presumably reflects the normal reaction to the anesthetic agent given. There were no further changes in CBF during cross-clamping. In 7 patients, the EEG showed signs of deterioration during the intraoperative vascular occlusion. In these patients, anesthesia did not cause any CBF change, whereas cross-clamping the artery induced a 33% decrease in CBF. In individual patients, the severity of EEG changes correlated with the decrease in CBF. The absence of a change in CBF by anesthesia and a decrease due to cross-clamping of the carotid artery may be explained by the presence of a more advanced cerebrovascular disease and an insufficiency to maintain CBF during cross-clamping.« less
Design and Construction of a Small Whole Body Inhalation Chamber
2010-07-30
by 12 7/8 inch high) were solvent welded onto this base using Weldon 4 (Ridout Plastics, San Diego CA). On the inside of each side wall a 2 inch...together using one inch spring clamps (Just Clamps, model 616,Atlanta Ga) on their respective flanges. These clamps were spaced evenly around the
Radiator debris removing apparatus and work machine using same
Martin, Kevin L [Washburn, IL; Elliott, Dwight E [Chillicothe, IL
2008-09-02
A radiator assembly includes a finned radiator core and a debris removing apparatus having a compressed air inlet and at least one compressed air outlet configured to direct compressed air through the radiator core. A work machine such as a wheel loader includes a radiator and a debris removing apparatus coupled with on-board compressed air and having at least one pressurized gas outlet configured to direct a gas toward the face of the radiator.
Yeongwan Seo; Han-Sup Han; Edward M. (Ted) Bilek; Jungkee Choi; Dusong Cha; Jungsoo Lee
2017-01-01
Economic analysis was conducted on the feasibility of operating a small-sized (500kW/hour) gasification power plant producing heat and electricity in a rural town surrounded by forests in the Republic of Korea. Cost factors that were considered over the plantâs 20-year life included wood procurement, a wood grab loader, a chipper, a chip dryer, a gasifier, a generator...
Unit Reference Sheet (URS) Cost Methodology.
1980-08-01
LAUNCHER MONORAIL GUIDED MISSILE: W/E (NIKE-HERCULES) L45740 LAUNCHER TUBULAR GUIDED MISSILE: (TOW) L45757 LAUNCHER ZERO LENGTH GUIDED MISSILE: (IMP-HAWK...L76762 LOADER TRANSPORTER GUIDED MISSILE: W/E (HAWK) M57503 MOBILE TARGET TRACKING SYSTEM: USED TO SUPPORT MQM 34 ( FIRE BEE) M57549 MOBILITY KIT GUIDED...HIGH RATE THREE BARREL W/E J96479 GUN AUTOMATIC 20 MILLIMETER: GAS OPERATED MANUAL OR ELECT FIRED J96481 GUN AUTOMATIC 20 MILLIMETER: ELECTRIC J96694 GUN
NASA Technical Reports Server (NTRS)
Bernhard, Ronald P.; Zolensky, Michael E.
1994-01-01
The Long Duration Exposure Facility (LDEF) was placed in low-Earth orbit (LEO) in 1984 and recovered 5.7 years later. The LDEF was host to several individual experiments specifically designed to characterize critical aspects of meteoroid and debris environment in LEO. However, it was realized from the beginning that the most efficient use of the satellite would be to examine the entire surface for impact features. In this regard, particular interest centered on common exposed materials that faced in all LDEF pointing directions. Among the most important of these materials was the tray clamps. Therefore, in an effort to better understand the nature of particulates in LEO and their effects on spacecraft hardware, residues found in impact features on LDEF tray clamp surfaces are being analyzed. This catalog presents all data from clamps from Bay B of the LDEF. NASA Technical Memorandum 104759 has cataloged impacts that occurred on Bay B (published March 1993). Subsequent catalogs will include clamps from succeeding bays of the satellite.
Micromolded PDMS planar electrode allows patch clamp electrical recordings from cells.
Klemic, Kathryn G; Klemic, James F; Reed, Mark A; Sigworth, Fred J
2002-06-01
The patch clamp method measures membrane currents at very high resolution when a high-resistance 'gigaseal' is established between the glass microelectrode and the cell membrane (Pflugers Arch. 391 (1981) 85; Neuron 8 (1992) 605). Here we describe the first use of the silicone elastomer, poly(dimethylsiloxane) (PDMS), for patch clamp electrodes. PDMS is an attractive material for patch clamp recordings. It has low dielectric loss and can be micromolded (Annu. Rev. Mat. Sci. 28 (1998) 153) into a shape that mimics the tip of the glass micropipette. Also, the surface chemistry of PDMS may be altered to mimic the hydrophilic nature of glass (J. Appl. Polym. Sci. 14 (1970) 2499; Annu. Rev. Mat. Sci. 28 (1998) 153), thereby allowing a high-resistance seal to a cell membrane. We present a planar electrode geometry consisting of a PDMS partition with a small aperture sealed between electrode and bath chambers. We demonstrate that a planar PDMS patch electrode, after oxidation of the elastomeric surface, permits patch clamp recording on Xenopus oocytes. Our results indicate the potential for high-throughput patch clamp recording with a planar array of PDMS electrodes.
Linear ultrasonic motor for absolute gravimeter.
Jian, Yue; Yao, Zhiyuan; Silberschmidt, Vadim V
2017-05-01
Thanks to their compactness and suitability for vacuum applications, linear ultrasonic motors are considered as substitutes for classical electromagnetic motors as driving elements in absolute gravimeters. Still, their application is prevented by relatively low power output. To overcome this limitation and provide better stability, a V-type linear ultrasonic motor with a new clamping method is proposed for a gravimeter. In this paper, a mechanical model of stators with flexible clamping components is suggested, according to a design criterion for clamps of linear ultrasonic motors. After that, an effect of tangential and normal rigidity of the clamping components on mechanical output is studied. It is followed by discussion of a new clamping method with sufficient tangential rigidity and a capability to facilitate pre-load. Additionally, a prototype of the motor with the proposed clamping method was fabricated and the performance tests in vertical direction were implemented. Experimental results show that the suggested motor has structural stability and high dynamic performance, such as no-load speed of 1.4m/s and maximal thrust of 43N, meeting the requirements for absolute gravimeters. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Wang, Jixin; Wang, Zhenyu; Yu, Xiangjun; Yao, Mingyao; Yao, Zongwei; Zhang, Erping
2012-09-01
Highly versatile machines, such as wheel loaders, forklifts, and mining haulers, are subject to many kinds of working conditions, as well as indefinite factors that lead to the complexity of the load. The load probability distribution function (PDF) of transmission gears has many distributions centers; thus, its PDF cannot be well represented by just a single-peak function. For the purpose of representing the distribution characteristics of the complicated phenomenon accurately, this paper proposes a novel method to establish a mixture model. Based on linear regression models and correlation coefficients, the proposed method can be used to automatically select the best-fitting function in the mixture model. Coefficient of determination, the mean square error, and the maximum deviation are chosen and then used as judging criteria to describe the fitting precision between the theoretical distribution and the corresponding histogram of the available load data. The applicability of this modeling method is illustrated by the field testing data of a wheel loader. Meanwhile, the load spectra based on the mixture model are compiled. The comparison results show that the mixture model is more suitable for the description of the load-distribution characteristics. The proposed research improves the flexibility and intelligence of modeling, reduces the statistical error and enhances the fitting accuracy, and the load spectra complied by this method can better reflect the actual load characteristic of the gear component.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ebey, Peter S.; Dole, James M.; Geller, Drew A.
2005-11-15
Beta-layering, the process of beta-decay heat-driven mass redistribution, has been demonstrated in a deuterium-tritium (D-T)-filled polymer sphere of the type required for fusion ignition experiments at the National Ignition Facility. This is the first report, to the best of the authors' knowledge, of a D-T layer formed in a permeation-filled sphere. The 2-mm-diam sphere was filled with D-T by permeation; cooled to cryogenic temperatures while in the high-pressure permeation vessel; and, while cold, removed to an optical axis where the D-T was frozen, melted, and beta-layered in a series of experiments over several weeks' time. This work was performed inmore » the Los Alamos National Laboratory cryogenic pressure loader system. The beta-layering time constant was 24.0 {+-} 2.5 min, less than the theoretical value of 26.8 min, and not showing the significant increase due to build-up of {sup 3}He often observed in beta-layered samples. Supercooling of the liquid D-T was observed. Neither the polymer target nor its tenting material showed visual signs of degradation after 5 weeks of exposure to D-T. Small external thermal gradients were used to shift the D-T material back and forth within the sphere.« less
Slickenside formation by surface melting during the mechanical excavation of rock
NASA Astrophysics Data System (ADS)
Spray, John G.
This work discusses the nature and origin of slickensides generated by the impingement of high-carbon steel teeth on sandstone during the mechanical excavation of boulders by back shovel and front loader. The slickensides show a number of morphological features that can be related to the direction and sense of tooth displacement, including striations, carrot-shaped grooves, curved fractures and steps. Scanning and transmission electron microscopy reveal that the slickensides comprise a layer of Fe-enriched, glass-bonded gouge (≤150 μm thick). The estimated shear stresses and velocities realized at the tooth-rock interface (175 MPa at 1 m s -1 for the back shovel and 100 MPa at 2 m s -1 for the front loader) indicate that a heat production of 150-200 MW m -2 and mean surface temperature of 1400-1700°C were achieved. XRF and microprobe analyses confirm that localized bulk melting and Fe-enrichment of the surface occurred during slip. The excavator-generated slickensides provide an analogue for the effects of a single co-seismic event in the evolution of a shallow, relatively dry fault surface. From a simple consideration of energetics under these conditions, it is apparent that localized surface melting should be commonplace. Such an analogue may be useful as a guide for recognizing melt features in natural slickensides, features that would otherwise tend to be obscured during lengthier periods of interseismic surface modification.
Nilius, B; Reichenbach, A
1988-06-01
Radial glial (Müller) cells were isolated from rabbit retinae by papaine and mechanical dissociation. Regional membrane properties of these cells were studied by using the patch-clamp technique. In the course of our experiments, we found three distinct types of large K+ conducting channels. The vitread process membrane was dominated by high conductance inwardly rectifying (HCR) channels which carried, in the open state, inward currents along a conductance of about 105 pS (symmetrical solutions with 140 mM K+) but almost no outward currents. In the membrane of the soma and the proximal distal process, we found low conductance inwardly rectifying (LCR) channels which had an open state-conductance of about 60 pS and showed rather weak rectification. The endfoot membrane, on the other hand, was found to contain non-rectifying very high conductance (VHC) channels with an open state-conductance of about 360 pS (same solutions). These results suggest that mammalian Müller cells express regional membrane specializations which are optimized to carry spatial buffering currents of excess K+ ions.
A dual switch controls bacterial enhancer-dependent transcription
Wiesler, Simone C.; Burrows, Patricia C.; Buck, Martin
2012-01-01
Bacterial RNA polymerases (RNAPs) are targets for antibiotics. Myxopyronin binds to the RNAP switch regions to block structural rearrangements needed for formation of open promoter complexes. Bacterial RNAPs containing the major variant σ54 factor are activated by enhancer-binding proteins (bEBPs) and transcribe genes whose products are needed in pathogenicity and stress responses. We show that (i) enhancer-dependent RNAPs help Escherichia coli to survive in the presence of myxopyronin, (ii) enhancer-dependent RNAPs partially resist inhibition by myxopyronin and (iii) ATP hydrolysis catalysed by bEBPs is obligatory for functional interaction of the RNAP switch regions with the transcription start site. We demonstrate that enhancer-dependent promoters contain two barriers to full DNA opening, allowing tight regulation of transcription initiation. bEBPs engage in a dual switch to (i) allow propagation of nucleated DNA melting from an upstream DNA fork junction and (ii) complete the formation of the transcription bubble and downstream DNA fork junction at the RNA synthesis start site, resulting in switch region-dependent RNAP clamp closure and open promoter complex formation. PMID:22965125
Yan, Shi; Wang, Xing; Wang, Yaqi; Lv, Chao; Wang, Yuzhao; Wang, Jia; Yang, Yue; Wu, Nan
2017-12-01
Postoperative pleural drainage markedly influences the length of hospital stay and the financial costs of medical care. The safety of chest tube clamping before removal has been documented. This study aims to determine if intermittent chest tube clamping shortens the duration of chest tube drainage and hospital stay after lung cancer surgery. We retrospectively analyzed 285 consecutive patients with operable lung cancer treated using lobectomy and systematic mediastinal lymphadenectomy. The chest tube management protocol in our institution was changed in January 2014, and thus, 222 patients (clamping group) were managed with intermittent chest tube clamping, while 63 patients (control group) were managed with a traditional protocol. Propensity score matching at a 1:1 ratio was applied to balance variables potentially affecting the duration of chest tube drainage. Analyses were performed to compare drainage duration and postoperative hospital stay between the two groups in the matched cohort. Multivariate logistic regression analyses were performed to predict the factors associated with chest tube drainage duration. The rates of thoracocentesis after chest tube removal were similar between the clamping and control groups in the whole cohort (0.5% vs. 1.6%, P=0.386). The rates of pyrexia were also comparable in the two groups (2.3% vs. 3.2%, P=0.685). After propensity score matching, 61 cases remained in each group. Both chest tube drainage duration (3.9 vs. 4.8 days, P=0.001) and postoperative stay (5.7 vs. 6.4 days, P=0.025) were significantly shorter in the clamping group than in the control group. Factors significantly associated with shorter chest tube drainage duration were female sex, chest tube clamping, left lobectomy, and video-assisted thoracoscopic surgery (VATS) (P<0.05). Intermittent postoperative chest tube clamping may decrease the duration of chest tube drainage and postoperative hospital stay while maintaining patient safety.
Majewski, Wacław; Krzyminiewski, Ryszard; Stanisić, Michał; Iskra, Maria; Krasiński, Zbigniew; Nowak, Marek; Dobosz, Bernadeta
2014-11-27
Aortic cross-clamping during abdominal aortic aneurysm (AAA) open repair leads to development of ischemia-reperfusion injury. Electron paramagnetic resonance spectroscopy (EPR) spin-trapping is a valuable method of direct measurement of free radicals. The objective of the study was to evaluate the results of EPR as a direct method of free radical measurement and degree of inflammatory response in open operative treatment of patients with AAA and aorto-iliac occlusive disease (AIOD). The study was performed on a group of 32 patients with AAA and 25 patients with AIOD scheduled for open repair. Peripheral venous blood for EPR spectroscopy and for SOD, GPx, ox-LDL, Il-6, TNF-alfa, CRP, and HO-1 were harvested. Selected parameters were established accordingly to specified EPR and immunohistochemical methods and analyzed between groups by Mann-Whitney U test and Wilcoxon matched-pairs signed-ranks test with Bonferroni correction. Free radicals level was correlated with the time of the aortic cross-clamping after the reperfusion of he first and second leg in AAA (r=0.7; r=0.47). ox-LDL in AAA decreased 5 min after reperfusion of the first leg (32.99 U/L, range: 14.09-77.12) and 5 min after reperfusion of the second leg (26.75 U/L, range: 11.56-82.12) and 24 h after the operation (25.85 U/L, range: 14.29-49.70). HO-1 concentration increased to above the level before intervention 24 h after surgery. The activities of GPx and SOD decreased 5 min after the first-leg reperfusion in AAA. Twenty-four hours after surgery, inflammatory markers increased in AAA to CRP was 14.76 ml/l (0.23-38.55), IL-6 was 141.22 pg/ml (84.3-591.03), TNF-alfa was 6.82 pg/ml (1.76-80.01) and AIOD: CRP was 18.44 mg/l (2.56-33.14), IL-6: 184.1 pg/ml (128.46-448.03), TNF-alfa was 7.74 pg/ml (1.74-74.74). EPR spin-trapping demonstrates temporarily elevated level of free radicals in early phase of reperfusion, leading to decrease antioxidants in AAA. Elevated free radical levels decreased 24 h after surgery due to various endogenous antioxidants and therapies.
Greenberg, Michael R
2009-09-01
Public and political opposition have made finding locations for new nuclear power plants, waste management, and nuclear research and development facilities a challenge for the U.S. government and the nuclear industry. U.S. government-owned properties that already have nuclear-related activities and commercial nuclear power generating stations are logical locations. Several studies and utility applications to the Nuclear Regulatory Commission suggest that concentrating locations at major plants (CLAMP) has become an implicit siting policy. We surveyed 2,101 people who lived within 50 miles of 11 existing major nuclear sites and 600 who lived elsewhere in the United States. Thirty-four percent favored CLAMP for new nuclear power plants, 52% for waste management facilities, and 50% for new nuclear laboratories. College educated, relatively affluent male whites were the strongest CLAMP supporters. They disproportionately trusted those responsible for the facilities and were not worried about existing nuclear facilities or other local environmental issues. Notably, they were concerned about continuing coal use. Not surprisingly, CLAMP proponents tended to be familiar with their existing local nuclear site. In short, likely CLAMP sites have a large and politically powerful core group to support a CLAMP policy. The challenge to proponents of nuclear technologies will be to sustain this support and expand the base among those who clearly are less connected and receptive to new nearby sites.
Zhang, H; Bolton, T B
1995-01-01
1. Single-channel recordings were made from cell-attached and isolated patches, and whole-cell currents were recorded under voltage clamp from single smooth muscle cells obtained by enzymic digestion of a small branch of the rat mesenteric artery. 2. In single voltage-clamped cells 1 mM uridine diphosphate (UDP) or guanidine diphosphate (GDP) added to the pipette solution, or pinacidil (100 microM) a K-channel opener (KCO) applied in the bathing solution, evoked an outward current of up to 100pA which was blocked by glibenclamide (10 microM). In single cells from which recordings were made by the 'perforated patch' (nystatin pipette) technique, metabolic inhibition by 1 mM NaCN and 10 mM 2-deoxy-glucose also evoked a similar glibenclamide-sensitive current. 3. Single K-channel activity was observed in cell-attached patches only infrequently unless the metabolism of the cell was inhibited, whereupon channel activity blocked by glibenclamide was seen; pinacidil applied to the cell evoked similar glibenclamide-sensitive channel activity. If the patch was pulled off the cell to form an isolated inside-out patch, similar glibenclamide-sensitive single-channel currents were observed in the presence of UDP and/or pinacidil to those seen in cell-attached mode; channel conductance was 20 pS (60:130 K-gradient) and openings showed no voltage-dependence and noisy inward currents, typical of the nucleoside diphosphate (NDP) activated K-channel (KNDP) seen previously in rabbit portal vein. 4. Formation of an isolated inside-out patch into an ATP-free solution did not increase the probability of channel opening which declined with time even when some single-channel activity had occurred in the cell-attached mode before detachment. However, application of 1 mM UDP or GDP, but not ATP, to inside-out patches evoked single-channel activity. Application of ATP-free solution to isolated patches, previously exposed to ATP and in which channel activity had been seen, did not evoke channel activity. 5. It is concluded that small conductance K-channels (KNDP) open in smooth muscle cells from this small artery in response to UDP or GDP acting from the inside, or pinacidil acting from the outside; the same channels open during inhibition of metabolism presumably mainly due to the rise in nucleoside diphosphates, but a fall in the ATP concentration on the inside of the channel did not by itself evoke channel activity.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:7735693
Tensile film clamps and mounting block for the rheovibron and autovibron viscoelastometer
NASA Technical Reports Server (NTRS)
Stoakley, Diane M. (Inventor); St.clair, Anne K. (Inventor); Little, Bruce D. (Inventor)
1989-01-01
A set of film clamps and a mounting block for use in the determination of tensile modulus and damping properties of films in a manually operated or automated Rheovibron is diagrammed. These clamps and mounting block provide uniformity of sample gripping and alignment in the instrument. Operator dependence and data variability are greatly reduced.
Plastic Clamp Retains Clevis Pin
NASA Technical Reports Server (NTRS)
Cortes, R. G.
1983-01-01
Plastic clamp requires no special installation or removal tools. Clamp slips easily over end of pin. Once engaged in groove, holds pin securely. Installed and removed easily without special tools - screwdriver or putty knife adequate for prying out of groove. Used to retain bearings, rollers pulleys, other parts that rotate. Applications include slowly and intermittently rotating parts in appliances.
The ac power line protection for an IEEE 587 Class B environment
NASA Technical Reports Server (NTRS)
Roehr, W. D.; Clark, O. M.
1984-01-01
The 587B series of protectors are unique, low clamping voltage transient suppressors to protect ac-powered equipment from the 6000V peak open-circuit voltage and 3000A short circuit current as defined in IEEE standard 587 for Category B transients. The devices, which incorporate multiple-stage solid-state protector components, were specifically designed to operate under multiple exposures to maximum threat levels in this severe environment. The output voltage peaks are limited to 350V under maximum threat conditions for a 120V ac power line, thus providing adequate protection to vulnerable electronic equipment. The principle of operation and test performance data is discussed.
A silicon micromachined resonant pressure sensor
NASA Astrophysics Data System (ADS)
Tang, Zhangyang; Fan, Shangchun; Cai, Chenguang
2009-09-01
This paper describes the design, fabrication and test of a silicon micromachined resonant pressure sensor. A square membrane and a doubly clamped resonant beam constitute a compound structure. The former senses the pressure directly, while the latter changes its resonant frequency according to deformation of the membrane. The final output relation between the resonant frequency and the applied pressure is deducted according to the structure mechanical properties. Sensors are fabricated by micromachining technology, and then sealed in vaccum. These sensors are tested by open-loop and close-loop system designed on purpose. The experiment results demonstrate that the sensor has a sensitivity of 49.8Hz/kPa and repeatability of 0.08%.
Cacho, J; Sevillano, J; de Castro, J; Herrera, E; Ramos, M P
2008-11-01
Insulin resistance plays a role in the pathogenesis of diabetes, including gestational diabetes. The glucose clamp is considered the gold standard for determining in vivo insulin sensitivity, both in human and in animal models. However, the clamp is laborious, time consuming and, in animals, requires anesthesia and collection of multiple blood samples. In human studies, a number of simple indexes, derived from fasting glucose and insulin levels, have been obtained and validated against the glucose clamp. However, these indexes have not been validated in rats and their accuracy in predicting altered insulin sensitivity remains to be established. In the present study, we have evaluated whether indirect estimates based on fasting glucose and insulin levels are valid predictors of insulin sensitivity in nonpregnant and 20-day-pregnant Wistar and Sprague-Dawley rats. We have analyzed the homeostasis model assessment of insulin resistance (HOMA-IR), the quantitative insulin sensitivity check index (QUICKI), and the fasting glucose-to-insulin ratio (FGIR) by comparing them with the insulin sensitivity (SI(Clamp)) values obtained during the hyperinsulinemic-isoglycemic clamp. We have performed a calibration analysis to evaluate the ability of these indexes to accurately predict insulin sensitivity as determined by the reference glucose clamp. Finally, to assess the reliability of these indexes for the identification of animals with impaired insulin sensitivity, performance of the indexes was analyzed by receiver operating characteristic (ROC) curves in Wistar and Sprague-Dawley rats. We found that HOMA-IR, QUICKI, and FGIR correlated significantly with SI(Clamp), exhibited good sensitivity and specificity, accurately predicted SI(Clamp), and yielded lower insulin sensitivity in pregnant than in nonpregnant rats. Together, our data demonstrate that these indexes provide an easy and accurate measure of insulin sensitivity during pregnancy in the rat.
Different methods of hilar clamping during partial nephrectomy: Impact on renal function.
Lee, Jeong Woo; Kim, Hwanik; Choo, Minsoo; Park, Yong Hyun; Ku, Ja Hyeon; Kim, Hyeon Hoe; Kwak, Cheol
2014-03-01
To evaluate the impact of different hilar clamping methods on changes in renal function after partial nephrectomy. We analyzed the clinical data of 369 patients who underwent partial nephrectomy for a single renal tumor of size ≤4.0 cm and a normal contralateral kidney. Patients were separated into three groups depending on hilar clamping method: non-clamping, cold ischemia and warm ischemia. Estimated glomerular filtration rate was examined at preoperative, nadir and 1 year postoperatively. Percent change in estimated glomerular filtration rate was used as the parameter to assess the renal functional outcome. Percent change in nadir estimated glomerular filtration rate in the non-clamping group was significantly less compared with the cold ischemia and warm ischemia groups (P < 0.001). However, no significant differences among the groups were noted in percent change of estimated glomerular filtration rate at 1 year (P = 0.348). The cold ischemia group had a similar serial change of postoperative renal function compared with the warm ischemia group. Percent change in 1-year estimated glomerular filtration rate increased with increasing ischemia time in the cold ischemia (P for trend = 0.073) and warm ischemia groups (P for trend = 0.010). On multivariate analysis, hilar clamping (both warm ischemia and cold ischemia) were significantly associated with percent change in nadir estimated glomerular filtration rate, but not in 1-year estimated glomerular filtration rate. Non-clamping partial nephrectomy results in a lower percent change in nadir estimated glomerular filtration rate, whereas it carries an estimated glomerular filtration rate change at 1 year that is similar to partial nephrectomy with cold ischemia and warm ischemia. Cold ischemia and warm ischemia provide a similar effect on renal function. Therefore, when hilar clamping is required, minimization of ischemia time is necessary. © 2013 The Japanese Urological Association.
Yi, Ruirong; Mukaiyama, Hiroyuki; Tachikawa, Takashi; Shimomura, Norihiro; Aimi, Tadanori
2010-01-01
In the bipolar basidiomycete Pholiota microspora, a pair of homeodomain protein genes located at the A-mating-type locus regulates mating compatibility. In the present study, we used a DNA-mediated transformation system in P. microspora to investigate the homeodomain proteins that control the clamp formation. When a single homeodomain protein gene (A3-hox1 or A3-hox2) from the A3 monokaryon strain was transformed into the A4 monokaryon strain, the transformants produced many pseudoclamps but very few clamps. When two homeodomain protein genes (A3-hox1 and A3-hox2) were transformed either separately or together into the A4 monokaryon, the ratio of clamps to the clamplike cells in the transformants was significantly increased to ca. 50%. We therefore concluded that the gene dosage of homeodomain protein genes is important for clamp formation. When the sip promoter was connected to the coding region of A3-hox1 and A3-hox2 and the fused fragments were introduced into NGW19-6 (A4), the transformants achieved more than 85% clamp formation and exhibited two nuclei per cell, similar to the dikaryon (NGW12-163 × NGW19-6). The results of real-time reverse transcription-PCR confirmed that sip promoter activity is greater than that of the native promoter of homeodomain protein genes in P. microspora. Thus, we concluded that nearly 100% clamp formation requires high expression levels of homeodomain protein genes and that altered expression of the A-mating-type genes alone is sufficient to drive true clamp formation. PMID:20453073
Niiranen, Laila; Lian, Kjersti; Johnson, Kenneth A; Moe, Elin
2015-02-27
Deinococcus radiodurans is an extremely radiation and desiccation resistant bacterium which can tolerate radiation doses up to 5,000 Grays without losing viability. We are studying the role of DNA repair and replication proteins for this unusual phenotype by a structural biology approach. The DNA polymerase III β subunit (β-clamp) acts as a sliding clamp on DNA, promoting the binding and processivity of many DNA-acting proteins, and here we report the crystal structure of D. radiodurans β-clamp (Drβ-clamp) at 2.0 Å resolution. The sequence verification process revealed that at the time of the study the gene encoding Drβ-clamp was wrongly annotated in the genome database, encoding a protein of 393 instead of 362 amino acids. The short protein was successfully expressed, purified and used for crystallisation purposes in complex with Cy5-labeled DNA. The structure, which was obtained from blue crystals, shows a typical ring-shaped bacterial β-clamp formed of two monomers, each with three domains of identical topology, but with no visible DNA in electron density. A visualisation of the electrostatic surface potential reveals a highly negatively charged outer surface while the inner surface and the dimer forming interface have a more even charge distribution. The structure of Drβ-clamp was determined to 2.0 Å resolution and shows an evenly distributed electrostatic surface charge on the DNA interacting side. We hypothesise that this charge distribution may facilitate efficient movement on encircled DNA and help ensure efficient DNA metabolism in D. radiodurans upon exposure to high doses of ionizing irradiation or desiccation.
Safety evaluation of large external fixation clamps and frames in a magnetic resonance environment.
Luechinger, Roger; Boesiger, Peter; Disegi, John A
2007-07-01
Large orthopedic external fixation clamps and related components were evaluated for force, torque, and heating response when subjected to the strong electromagnetic fields of magnetic-resonance (MR) imaging devices. Forces induced by a 3-Tesla (T) MR scanner were compiled for newly designed nonmagnetic clamps and older clamps that contained ferromagnetic components. Heating trials were performed in a 1.5 and in a 3 T MR scanner with two assembled external fixation frames. Forces of the newly designed clamps were more than a factor 2 lower as the gravitational force on the device whereas, magnetic forces on the older devices showed over 10 times the force induced by earth acceleration of gravity. No torque effects could be found for the newly designed clamps. Temperature measurements at the tips of Schanz screws in the 1.5 T MR scanner showed a rise of 0.7 degrees C for a pelvic frame and of 2.1 degrees C for a diamond knee bridge frame when normalized to a specific absorption rate (SAR) of 2 W/kg. The normalized temperature increases in the 3 T MR scanner were 0.9 degrees C for the pelvic frame and 1.1 degrees C for the knee bridge frame. Large external fixation frames assembled with the newly designed clamps (390 Series Clamps), carbon fiber reinforced rods, and implant quality 316L stainless steel Schanz screws met prevailing force and torque limits when tested in a 3-T field, and demonstrated temperature increase that met IEC-60601 guidelines for extremities. The influence of frame-induced eddy currents on the risk of peripheral nerve stimulation was not investigated. Copyright 2006 Wiley Periodicals, Inc.
Griggio, F; Jesse, S; Kumar, A; Ovchinnikov, O; Kim, H; Jackson, T N; Damjanovic, D; Kalinin, S V; Trolier-McKinstry, S
2012-04-13
The role of long-range strain interactions on domain wall dynamics is explored through macroscopic and local measurements of nonlinear behavior in mechanically clamped and released polycrystalline lead zirconate-titanate (PZT) films. Released films show a dramatic change in the global dielectric nonlinearity and its frequency dependence as a function of mechanical clamping. Furthermore, we observe a transition from strong clustering of the nonlinear response for the clamped case to almost uniform nonlinearity for the released film. This behavior is ascribed to increased mobility of domain walls. These results suggest the dominant role of collective strain interactions mediated by the local and global mechanical boundary conditions on the domain wall dynamics. The work presented in this Letter demonstrates that measurements on clamped films may considerably underestimate the piezoelectric coefficients and coupling constants of released structures used in microelectromechanical systems, energy harvesting systems, and microrobots.
NASA Technical Reports Server (NTRS)
Barber, Tim Daniel (Inventor); Hindle, Timothy (Inventor); Young, Ken (Inventor); Davis, Torey (Inventor)
2014-01-01
Embodiments of a launch lock assembly are provided, as are embodiments of a spacecraft isolation system including one or more launch lock assemblies. In one embodiment, the launch lock assembly includes first and second mount pieces, a releasable clamp device, and an axial gap amplification device. The releasable clamp device normally maintains the first and second mount pieces in clamped engagement; and, when actuated, releases the first and second mount pieces from clamped engagement to allow relative axial motion there between. The axial gap amplification device normally residing in a blocking position wherein the gap amplification device obstructs relative axial motion between the first and second mount pieces. The axial gap amplification device moves into a non-blocking position when the first and second mount pieces are released from clamped engagement to increase the range of axial motion between the first and second mount pieces.
Structural basis of human PCNA sliding on DNA
NASA Astrophysics Data System (ADS)
de March, Matteo; Merino, Nekane; Barrera-Vilarmau, Susana; Crehuet, Ramon; Onesti, Silvia; Blanco, Francisco J.; de Biasio, Alfredo
2017-01-01
Sliding clamps encircle DNA and tether polymerases and other factors to the genomic template. However, the molecular mechanism of clamp sliding on DNA is unknown. Using crystallography, NMR and molecular dynamics simulations, here we show that the human clamp PCNA recognizes DNA through a double patch of basic residues within the ring channel, arranged in a right-hand spiral that matches the pitch of B-DNA. We propose that PCNA slides by tracking the DNA backbone via a `cogwheel' mechanism based on short-lived polar interactions, which keep the orientation of the clamp invariant relative to DNA. Mutation of residues at the PCNA-DNA interface has been shown to impair the initiation of DNA synthesis by polymerase δ (pol δ). Therefore, our findings suggest that a clamp correctly oriented on DNA is necessary for the assembly of a replication-competent PCNA-pol δ holoenzyme.
Management of umbilical cord clamping.
Webbon, Lucy
2013-02-01
The Royal College of Midwives (RCM) has updated its third stage of labour guidelines (RCM 2012) to be clearly supportive of a delay in umbilical cord clamping, although specific guidance on timing is yet to be announced. It is therefore imperative that both midwives and student midwives understand and are able to integrate delaying into their practice, as well as communicating to women the benefits; only in this way can we give women fully informed choices on this aspect of care. The main benefit of delayed cord clamping is the protection it can provide in reducing childhood anaemia, which is a major issue, especially in poorer countries. A review of the evidence found no risks linked to delayed clamping, and no evidence that it cannot be used in combination with the administration of uterotonic drugs. Delayed cord clamping can be especially beneficial for pre term and compromised babies.
NASA Astrophysics Data System (ADS)
Jia, Xin-Hong
2006-12-01
The theoretical model on gain-clamped semiconductor optical amplifiers (GC-SOAs) based on compensating light has been constructed. Using this model, the effects of insertion position and peak reflectivity of the fiber Bragg grating (FBG) on the gain clamping and noise figure (NF) characteristics of GC-SOA are analyzed. The results show that the effect of the FBG insertion position on gain clamping is slight, but the lower NF can be obtained for input FBG-type GC-SOA; when the FBG peak wavelength is designed to close the signal wavelength, the gain clamping and NF characteristics that can be reached are better. Further study shows that, with the increased peak reflectivity of the FBG, the critical input power is broadened and the gain tends to be varied slowly; the larger bias current is helpful to raise gain and decrease the noise figure but is harmful to a gain flatness characteristic.
The Nano-Patch-Clamp Array: Microfabricated Glass Chips for High-Throughput Electrophysiology
NASA Astrophysics Data System (ADS)
Fertig, Niels
2003-03-01
Electrophysiology (i.e. patch clamping) remains the gold standard for pharmacological testing of putative ion channel active drugs (ICADs), but suffers from low throughput. A new ion channel screening technology based on microfabricated glass chip devices will be presented. The glass chips contain very fine apertures, which are used for whole-cell voltage clamp recordings as well as single channel recordings from mammalian cell lines. Chips containing multiple patch clamp wells will be used in a first bench-top device, which will allow perfusion and electrical readout of each well. This scalable technology will allow for automated, rapid and parallel screening on ion channel drug targets.
Surface characterization of selected LDEF tray clamps
NASA Technical Reports Server (NTRS)
Cromer, T. F.; Grammer, H. L.; Wightman, J. P.; Young, Philip R.; Slemp, Wayne S.
1993-01-01
The surface characterization of chromic acid anodized 6061-T6 aluminum alloy tray clamps has shown differences in surface chemistry depending upon the position on the Long Duration Exposure Facility (LDEF). Water contact angle results showed no changes in wettability of the tray clamps. The overall surface topography of the control, trailing edge(E3) and leading edge(D9) samples was similar. The thickness of the aluminum oxide layer for all samples determined by Auger depth profiling was less than one micron. X-ray photoelectron spectroscopy (XPS) analysis of the tray clamps showed significant differences in the surface composition. Carbon and silicon containing compounds were the primary contaminants detected.